HomeMy WebLinkAboutKvichak River Igiugig App11/10/2008 09:38 9075333217 IGIUGIG VILLAGE CNCL PAGE 02/03IGIUGIGTRIBALVILLAGECOUNCILAKA.Igiugig Village Council
P.O.Box 4008
Igiugig,AK 99613
Phone:(907)533-3211 or Fax:(907)533·3217 www,.ig:i.ugig",c~Q.ill.e-mail:igLugtg@bristolhaY·r:P.!A
November I 0,2008
Renewable Energy Grant Fund
Alaska Energy Authority
813 West Northern Lights Blvd.
Anchorage,AK 99503
Re:Igiugig Village Council -Renewable Energy Fund Grant Application -Letter of
Commitment
Application Review Committee:
Igiugig Village Council d/b/a Igiugig Electric Company is pleased to submit the attached
appl1cation for a Renewable Energy Fund Grant for a river in-stream energy conversion (RTSEC)
project,an eligible renewable energy project as defined under HB 152.Igiugig Village Council is
authorized by the Regulatory Commission of Alaska to provide power to the community of
Igiugig under Certificate of Public Convenience and Necessity,CPC&N No.681.
The attached Application documents and describes the proposed RISEC project.The total
estimated cost of design,permitting,construction,and development and testing is $2,302,630.
The estimated fuel savings as a result of the commercial scale project is I 5,OOO-gallons starting in
year 5.Igiugig Village Council commits to this project a cash Match of up to $50,000.
Igiugig Village Council strives to keep electric costs as Iowa possible by maximizing operating
efficiencies and reducing operating costs.Thi.s project will provide <!l.significant improvement
toward meeting this continued goa.l,and will greatly benefit the community ofIgiugig,as well as
other mral Alaska communities interested in implementing a RISEC technology project.
Igiugig Village Council welcomes and fully supports this opportunity to work with the Alaska
Energy Authority to implement this innovative RlSEC project,and requests the Review
Committee carefully review the merits of this application.
We welcome your review and evaluation of our proposal,and look forward to working with you
on this project.If you have any questions about this project,please feel free to contact me at
(907)533~3217
i;~~
Dallia Andrew
Igiugig Village Council President
~~
Bonn.ie Thurston
Village Administrator
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 1 of 25 9/2/2008
Application Forms and Instructions
The following forms and instructions are provided for preparing your application for a
Renewable Energy Fund Grant. An electronic version of the Request for Applications (RFA)
and the forms are available online at http://www.akenergyauthority.org/RE_Fund.html
The following application forms are required to be submitted for a grant recommendation:
Grant Application
Form
GrantApp.doc Application form in MS Word that includes an outline of
information required to submit a complete application.
Applicants should use the form to assure all information is
provided and attach additional information as required.
Application Cost
Worksheet
Costworksheet.doc Summary of Cost information that should be addressed
by applicants in preparing their application.
Grant Budget
Form
GrantBudget.xls A detailed grant budget that includes a breakdown of
costs by task and a summary of funds available and
requested to complete the work for which funds are being
requested.
Grant Budget
Form Instructions
GrantBudgetInstr.pdf Instructions for completing the above grant budget form.
• If you are applying for grants for more than one project, provide separate application
forms for each project.
• Multiple phases for the same project may be submitted as one application.
• If you are applying for grant funding for more than one phase of a project, provide a plan
and grant budget for completion of each phase.
• If some work has already been completed on your project and you are requesting
funding for an advanced phase, submit information sufficient to demonstrate that the
preceding phases are satisfied and funding for an advanced phase is warranted.
• If you have additional information or reports you would like the Authority to consider in
reviewing your application, either provide an electronic version of the document with
your submission or reference a web link where it can be downloaded or reviewed.
REMINDER:
• Alaska Energy Authority is subject to the Public Records Act, AS 40.25 and materials
submitted to the Authority may be subject to disclosure requirements under the act if no
statutory exemptions apply.
• All applications received will be posted on the Authority web site after final
recommendations are made to the legislature.
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 2 of 25 9/3/2008
SECTION 1 – APPLICANT INFORMATION
Name (Name of utility, IPP, or government entity submitting proposal)
Igiugig Village Council d/b/a Igiugig Electric Company
Type of Entity:
Certificated Electric Utility
Mailing Address
Igiugig Village Council
PO Box 4008
Igiugig, Alaska 99613
Physical Address
Same
Telephone
907-533-3211
Fax
907-533-3217
Email
bsthurst@aol.com
1.1 APPLICANT POINT OF CONTACT
Name
Bonnie Thurston
Title
Village Administrator
Mailing Address
Igiugig Village Council
PO Box 4008
Igiugig, Alaska 99613
Telephone
907-533-3211
Fax
907-533-3217
Email
bsthurst@aol.com
1.2 APPLICANT MINIMUM REQUIREMENTS
Please check as appropriate. If you do not to meet the minimum applicant requirements, your
application will be rejected.
1.2.1 As an Applicant, we are: (put an X in the appropriate box)
X An electric utility holding a certificate of public convenience and necessity under AS
42.05, or
An independent power producer, or
A local government, or
A governmental entity (which includes tribal councils and housing authorities);
Yes
or
No
1.2.2. Attached to this application is formal approval and endorsement for its project by
its board of directors, executive management, or other governing authority. If a
collaborative grouping, a formal approval from each participant’s governing
authority is necessary. (Indicate Yes or No in the box )
Yes
or
No
1.2.3. As an applicant, we have administrative and financial management systems and
follow procurement standards that comply with the standards set forth in the grant
agreement.
Yes
or
No
1.2.4. If awarded the grant, we can comply with all terms and conditions of the attached
grant form. (Any exceptions should be clearly noted and submitted with the
application.)
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 3 of 25 9/3/2008
SECTION 2 – PROJECT SUMMARY
Provide a brief 1-2 page overview of your project.
2.1 PROJECT TYPE
Describe the type of project you are proposing, (Reconnaissance; Resource Assessment/
Feasibility Analysis/Conceptual Design; Final Design and Permitting; and/or Construction) as
well as the kind of renewable energy you intend to use. Refer to Section 1.5 of RFA.
The Igiugig Village Council (IVC) proposes to complete a multi-phase project to develop, test, and
ultimately commercialize a river in-stream energy conversion (RISEC) project in the Kvichak River at
Igiugig, Alaska. RISEC technology uses water turbines (similar to wind turbines) to convert the kinetic
energy of a free-flowing river into electricity.
The Igiugig Village Council d/b/a Igiugig Electric Company operates the electric utility in the community
of Igiugig under Regulatory Commission of Alaska Certificate of Public Convenience and Necessity No.
681. The Igiugig power plant is an existing facility in operation prior to August 20, 2008. The proposed
RISEC project is a new project that is not in operation.
The first phase of the project has been completed. A Scoping Brief was prepared by IVC that identified
the potential resource and the community commitment to this project. IVC then teamed with the Electric
Power Research Institute (EPRI), in conjunction with the Alaska Energy Authority, to further investigate
the resource and prepare a system level design, performance, and cost assessment (refer to Appendix F).
Phase II of this project is to conduct side-by-side in-water testing of at least two different near-
commercial RISEC devices to evaluate electro-mechanical performance and assess potential
environmental impacts. The steps under this phase, include:
• assess the available energy resource,
• develop an environmental monitoring program,
• secure a FERC hydrokinetic pilot project license,
• develop and submit an RFP to RISEC equipment manufacturers,
• procure and employ the RISEC devices,
• monitor and evaluate performance and environmental impacts
• analyze and report findings and recommendations
Phase III consists of final design and permitting of a commercial scale RISEC project, and includes:
• geotechnical investigation
• complete NEPA environmental permitting and secure FERC project license
• develop and submit an RFP to RISEC equipment manufacturers
• select commercial scale RISEC equipment,
• finalize business plan and project cost/benefit
• finalize project design and electric grid integration
Phase IV includes:
• material procurement and mobilization
• RISEC installation and commissioning
• Environmental monitoring
• Ongoing performance and environmental monitoring and reporting
The phased approach to this project will enable IVC to make an informed evaluation regarding the
feasibility of incorporating renewable river energy into its energy portfolio, while simultaneously
facilitating the commercial development of this new technology and sharing the results with other
communities in the region and Alaska.
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 4 of 25 9/3/2008
2.2 PROJECT DESCRIPTION
Provide a one paragraph description of your project. At a minimum include the project location,
communities to be served, and who will be involved in the grant project.
The Village of Igiugig is located at the outlet of Lake Iliamna, 240 air miles southwest of Anchorage, on
the southern shore of the Kvichak River. Igiugig has a year-round population of 56 (predominantly
Yupik, Aleut, and Athabascan) rising in summer to about 75. Igiugig also provides goods and services to
six area tourism lodges and their respective clients and workforce of 90 additional persons per week.
This lake outlet location provides an ideal site for the study, testing and implementation of river in-stream
energy conversion that will also benefit other Alaska communities considering this form of renewable
energy. A RISEC plant will convert available river kinetic energy into electric power, and feed into the
existing Igiugig electric grid to reduce diesel fuel consumption at the Igiugig power plant. Direct
beneficiaries include the Lake and Peninsula School District (LPSD) and Igiugig electric service
customers.
IVC will be the Grantee under the Renewable Energy Fund project. IVC has teamed up with the
engineering firm of Alaska Energy and Engineering, Inc. (AE&E), Electric Power Research Institute
(EPRI), and the Bristol Bay Research and Science Institute (BBSRI). AE&E also brings to the team the
geotechnical firm of Duane Miller Associates, LLC.
AE&E is an Alaska-owned, Anchorage-based firm incorporated in 1993 specifically to provide design
and project management services for rural energy projects. AE&E has built its reputation on the ability to
provide practical design solutions and hands-on construction support to effectively meet the challenges of
rural Alaska. We have fostered excellent working relationships with permitting and regulatory agencies,
which ensures that our projects comply with current interpretation of state and federal regulations. The
engineering staff of AE&E has extensive experience designing and constructing projects in remote sites
throughout the state with particular emphasis in western Alaska. Our primary field of expertise is electric
power generation and distribution, rural fuel storage and handling facilities, and energy systems
integration.
EPRI is a non-profit, public-benefit organization leading innovation in strategic areas of electricity
technology through public-private partnerships. Over the past two and half years, EPRI has performed
techno feasibility studies for offshore wave and tidal energy conversion; wave energy in 2004 and tidal in
2005 and early 2006. The tidal work evaluated the application of water turbines to convert the kinetic
energy in a tidal stream to electricity. The tidal feasibility studies, for good sites, made a compelling case
for investing in projects using this technology to diversify our energy supply portfolio. The case made
was so compelling that within a couple of months of the completion of the EPRI feasibility studies,
approximately 30 applications for preliminary permits were filed by private investors to the FERC and
Nova Scotia Power announced a multi-million dollar tidal in-stream pilot plant in that province.
BBSRI is an independent research institute established by the Bristol Bay Economic Development
Corporation and is one of its non-profit subsidiaries. This multi-disciplinary team uses its technical
expertise to devise and conduct scientific research and monitoring to improve management of fish stocks,
fisheries, and the environments of the Bristol Bay region. The Institute also provides scholarships and on-
the-job training to increase participation by area residents. BBSRI is currently under contract to the
Alaska Department of Fish and Game to manage an ongoing seasonal Kvichak River smolt outmigration
study. They have an established base camp near Igiugig with on-site personnel experienced in the
operation of both traditional single beam upward-looking sonar and side-looking imaging DIDSON sonar
equipment. The fact that this crew will already be situated near the proposed RISEC installation site will
result in substantial savings for the planned RISEC fish impact study. AE&E has a long history of
successful energy-related projects throughout Alaska, and has worked with both IVC and the school
district on numerous projects dating back to 1995. EPRI just concluded an intensive feasibility study of
RISEC technology in Alaska and at the Igiugig site in particular.
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 5 of 25 9/3/2008
2.3 PROJECT BUDGET OVERVIEW
Briefly discuss the amount of funds needed, the anticipated sources of funds, and the nature and source
of other contributions to the project. Include a project cost summary that includes an estimated total cost
through construction.
The estimated cost of construction for all three phases is $2,396,830 Of this amount, $44,200 has been
expended on completed tasks and IVC has committed to provide a cash match in the amount of $50,000,
as well as use of heavy equipment as a contribution in aid of construction. The balance requested for this
project from the Renewable Energy Grant Fund is $2,302,630.
There are a variety of sources of capital that may be available for this project, including Department of
Agriculture, Rural Utilities Service grants and loans, Denali Commission funding, Bristol Bay Economic
Development Corporation funding, private financing and commercial loans. However, due to the potential
for this technology to have widespread application in many parts of Alaska, and the extensive pilot
project testing and environmental evaluation costs required to document the validity of this technology,
IVC is requesting full funding from the Renewable Energy Fund grant program so that we may proceed
immediately with this vital project to the benefit of the community and all of rural Alaska.
PHASE I. RECONNAISSANCE
Igiugig Electric Hydropower Scoping Brief (1/08) --
Alaska RISEC Final Feasibility Study Report (10/08) $9,200
PHASE I TOTAL $9,200
PHASE II. FEASIBILITY ANALYSIS, RESOURCE ASSESSMENT & CONCEPTUAL DESIGN
Existing Energy Assessment (Igiugig RPSU CDR 11/08) $35,000
Kvichak River Current Profile, Bathymetry and Preliminary Geotechnical Study $82,000
RISEC Pilot Project Permitting, Installation, Environmental Impact Study and
Performance Monitoring $307,500
Phase II Engineering, Permitting and Project Management $127,500
EPRI Phase II Consulting $72,500
Phase II Contingency @ 15% $93,675
PHASE II TOTAL $718,175
PHASE III. FINAL DESIGN & PERMITTING
Phase III Engineering, Permitting and Project Management $98,750
Commercial RISEC Installation Geotechnical Investigation $236,000
EPRI Phase III Consulting $50,500
Phase III Contingency @ 15% $57,788
PHASE III TOTAL $443,038
PHASE IV. CONSTRUCTION, COMMISSIONING, OPERATION & REPORTING
Fabrication, Construction and Installation of Commercial RISEC Device(s) $710,200
Commercial Project Environmental Impact Study $75,000
Phase IV Engineering and Project Management $96,250
EPRI Phase IV Consulting & Long Term Monitoring $185,000
Phase IV Contingency @ 15% $159,968
PHASE IV TOTAL $1,226,418
PROJECT TOTAL $2,396,830
Less Local Match Funds ($50,000)
Less Completed Tasks ($44,200)
TOTAL GRANT REQUEST $2,302,630
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 6 of 25 9/3/2008
2.4 PROJECT BENEFIT
Briefly discuss the financial benefits that will result from this project, including an estimate of economic
benefits(such as reduced fuel costs) and a description of other benefits to the Alaskan public.
Local economic benefits
The EPRI feasibility study evaluated the financial benefits expected to accrue from this project. While the
Phase II pilot project development portion of the project does not have a simple payback, the estimated
payback period for the commercial scale facility is 3 to 4 years, at an avoided cost of diesel fuel at 65
cents/kWh, including the initial capital outlay and ongoing operation and maintenance cost of the RISEC
plant. Additional benefits include the development of an emission-less renewable energy resource and a
reduction in carbon footprint, as well as local economic development during the installation, monitoring,
and evaluation phases of the project.
Benefits to Alaskan public
The primary benefit of this project reaches far beyond the Village of Igiugig. As a pilot demonstration
project, the resulting data will aid the Authority and other Alaska communities considering RISEC
renewable energy and help to evaluate the current technology, provide a decision-making framework,
advance subsequent design and permitting processes, and ultimately refine and reduce installation and
operating costs.
2.5 PROJECT COST AND BENEFIT SUMARY
Include a summary of your project’s total costs and benefits below.
2.5.1 Total Project Cost
(Including estimates through construction.)
$ 2,396,830
2.5.2 Grant Funds Requested in this application. $ 2,302,630
2.5.3 Other Funds to be provided (Project match) $ 94,200
2.5.4 Total Grant Costs (sum of 2.5.2 and 2.5.3) $ 2,396,830
2.5.5 Estimated Benefit (Savings) $ refer to above
2.5.6 Public Benefit (If you can calculate the benefit in terms of
dollars please provide that number here and explain how
you calculated that number in your application.)
$ refer to above
SECTION 3 – PROJECT MANAGEMENT PLAN
Describe who will be responsible for managing the project and provide a plan for successfully
completing the project within the scope, schedule and budget proposed in the application.
3.1 Project Manager
Tell us who will be managing the project for the Grantee and include a resume and references
for the manager(s). If the applicant does not have a project manager indicate how you intend to
solicit project management Support. If the applicant expects project management assistance
from AEA or another government entity, state that in this section.
Bonnie Thurston, Igiugig Village Administrator, will be the Grant Manager. She will be the single
point of contact with AEA and will execute all grant, contractual and administrative responsibilities. Ms.
Thurston has experience as a grant facilitator and as an administrator, working extensively with state and
federal agencies as well as the Lake and Peninsula School District. She is skilled in tracking grants,
communications, and deals smoothly and professionally with executive officers, upper management,
employees, vendors, and customers in day-to-day and occasionally adverse situations.
Brian C. Gray, P.E., AE&E , will serve as the Project Manager. He will work with the Grant Manager
to commit essential engineering disciplines to ensure a successful project. For the past 17 years he has
served as project manager and project engineer for the design and construction of rural power generation,
fuel storage, and energy-related projects in Alaska communities totaling more than $110 million. His
responsibilities have included feasibility analysis, program development, budgeting, design, permitting,
construction management, and system startup. For this project, Mr. Gray will establish specific man hour
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 7 of 25 9/3/2008
and reimbursable budgets, and schedule the necessary technical staff. He will track specific contractual
deliverables against the schedule to ensure adequate resources are available to meet critical milestones.
He will analyze all relevant issues such as available shipping options, permitting and site control issues,
and procurement requirements. Drawing on the expertise of our team, he will assign specific project tasks
to responsible team members. Mr. Gray will oversee all technical work and coordinate the efforts of our
team to ensure the efficient and cost effective production of project designs. He will develop a realistic
project schedule to address critical issues in proper sequence to minimize cost and maximize construction
resources.
Mr. Gray will be directly responsible for the quality of all work produced by our team. He will oversee
and review all critical tasks and provide input and support on all significant design issues. He will ensure
that design review comments from the Authority and the Village of Igiugig are adequately addressed and
incorporated into final design documents, and he will manage the logistics of construction support. His
working relationship with Authority staff dates to the early 1990s. Mr. Gray has the authority to assign
the technical personnel and resources necessary to successfully complete this project.
3.2 Project Schedule
Include a schedule for the proposed work that will be funded by this grant. (You may include a
chart or table attachment with a summary of dates below.)
The RISEC project schedule, for this multi-phase, multi-year, pilot through commercialization project, is
shown in detail on this and the next page:
IGIUGIG RISEC PROJECT SCHEDULE
Task/Year 2009 2010 2011
1st
Qrtr
2nd
Qrtr
3rd
Qrtr
4th
Qrtr
1st
Qrtr
2nd
Qrtr
3rd
Qrtr
4th
Qrtr
1st
Qrtr
2nd
Qrtr
3rd
Qrtr
4th
Qrtr
PHASE II
FUNDING ANNOUNCED X
FERC RISEC PILOT
PROJECT LICENSE x----------------------------------------------x
KVICHAK RIVER ADCP &
BATHYMETRY & PRELIM.
GEOTECH EVALUATION
x------x
ANALYZE DATA &
DEVELOP PILOT DEVICE
PERFORMANCE SPECS
x-------x
PILOT DEVICE
PROCUREMENT x---------------x
DELIVER, INSTALL & TEST
RISEC PILOT DEVICE(S) x---------------------------x
FISH IMPACT STUDY
PLANNING, FIELD WORK,
ANALYSIS & REPORT
x---------------------------------------------------x
DATA CAPTURE
PLANNING, MONITORING,
ANALYSIS & REPORT
x---------------------------------------------------x
COMPREHENSIVE
ANALYSIS & GO/NO-GO x------x
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 8 of 25 9/3/2008
IGIUGIG RISEC PROJECT SCHEDULE (CONT’D)
Task/Year 2012 2013 2014
1st
Qrtr
2nd
Qrtr
3rd
Qrtr
4th
Qrtr
1st
Qrtr
2nd
Qrtr
3rd
Qrtr
4th
Qrtr
1st
Qrtr
2nd
Qrtr
3rd
Qrtr
4th
Qrtr
PHASE III
DEVELOP COMMERCIAL
DEVICE PERFORMANCE
SPECS
x-------------------x
STRUCTURAL ELEMENT
DESIGN x-----------x
CONDUCT GEOTECH
INVESTIGATION x--x
FERC & STATE
PERMITTING & SITE
CONTROL FOR
COMMERCIAL DEVICE(S)
x---------------------------x
BUSINESS & OPERATIONS
PLANS x---------------------------x
PHASE IV
COMMERCIAL DEVICE(S)
PROCUREMENT x-------------------x
STRUCTURAL ELEMENT
CONSTRUCTION x-------x
DEPLOYMENT OF
COMMERCIAL RISEC
DEVICE(S)
x--x
GRID EXTENSION &
INTEGRATION x-----x
COMMISION RISEC
DEVICE(S) AND REMOTE
MONITORING SYSTEM
x-x
FISH IMPACT FOLOW-UP
STUDY ON COMMERCIAL
INSTALLATION
x----x
FINAL REPORT, AS-
BUILTS, O&M MANUALS x-----------x
CONTINUING LONG TERM
PERFORMANCE
MONITORING & ANALYSIS
x--------
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 9 of 25 9/2/2008
3.3 Project Milestones
Define key tasks and decision points in your project and a schedule for achieving them.
Project milestones (see above tables for details of components and dates) include:
• Kickoff Meeting
o Present a detailed project plan and assure mutual expectations among project participants.
• RISEC Pilot Device Design/Solicitation
o The RPF for two RISEC test devices will be completed by the end of 2009 based on data
from acoustic Doppler current profiles, bathymetric surveys and preliminary
Geotechnical studies of the Kvichak River.
• FERC Permitting, Environmental Monitoring Plan
o The fish impact study plan and the FERC license should be in hand by the second quarter
of 2010, ready for arrival of the RISEC devices and testing.
• Pilot Project Testing
o Phase II pilot testing of the vertical and horizontal RISEC devices will take place during
4 quarters, from mid 2010 to mid 2011. Upon completion of testing and inspections, a
Go/No Go decision for Phase III (commercial design & permitting) will be made by the
end of 2011 based on a comprehensive financial, performance, and environmental
analysis.
• Cost/Benefit/Recommendations for Commercial Installation
o The end of Phase III in mid 2013 will have the final business plan and operational plans
completed as well as permitting with FERC, Alaska Coastal Management, Corps of
Engineers, Fire Marshal, and others. Site control will have been secured.
• Commercialization
o Completion of construction and beginning of operations will take place in the third
quarter of 2013 with installation of grid integration equipment and cable interties.
Monitoring of juvenile and adult fish will be during the first salmon season following the
commercial RISEC installation to verify the response is as predicted.
• Final Report/Continuing Long-term Monitoring
o The success of the RISEC plant will be analyzed with recommendations by the end of
2014. EPRI will continue to remotely monitor the Igiugig RISEC system for at least three
years following the completion of the project in order to provide a long term performance
evaluation of the RISEC technology employed and to determine the overall benefits to
the community.
3.4 Project Resources
Describe the personnel, contractors, equipment, and services you will use to accomplish the
project. Include any partnerships or commitments with other entities you have or anticipate will
be needed to complete your project. Describe any existing contracts and the selection process
you may use for major equipment purchases or contracts. Include brief resumes and references
for known, key personnel, contractors, and suppliers as an attachment to your application.
In addition to the Grant Manager and Project Manager annotated in Section 3.1, our team includes the
following personnel, contractors, equipment and services. IVC will be the single point of contact and will
execute all grant, contractual, and administrative responsibilities. AE&E will provide all design,
permitting, system integration, and construction management. EPRI will serve as RISEC technical
consultants. BBSRI will plan and implement fish studies and environmental monitoring.
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 10 of 25 9/3/2008
Alaska Energy & Engineering, Inc.
John Dickerson, EIT, AE&E, will be the lead Design Engineer/Construction Manager. He has
more than 25 years of Alaska construction, engineering, project management, and business management
experience. For the past nine years, he has served as project engineer for the design and construction of
over $25 million worth of rural power system and fuel storage projects in Alaska communities.
Responsibilities have included site investigations, design, drafting, cost estimation, procurement,
logistics, and construction management. As a design engineer, Mr. Dickerson has prepared construction
documents for heating, ventilation, plumbing, refrigeration, fuel storage and ASME B31.3 process piping
systems for a range of commercial and industrial facilities. His has developed a long working relationship
with the Village of Igiugig and the Lake and Peninsula School District as well as the Authority.
Steven J. Stassel, P.E., AE&E president, will accomplish the Environmental Permitting. He has
more than 21 years of engineering experience, including rural Alaska energy projects in more than 125
communities. He has been responsible for permitting and fulfilling all regulatory and environmental
compliance requirements (Wetlands, Flood Mitigation, Coastal Zone, NEPA Environmental review) and
state and federal agency coordination. He has successfully permitted more than 40 energy-related projects
in rural Alaska.
Duane Miller Associates, LLC
Duane L. Miller, P.E., DMA, will provide Geotechnical Services as a subconsultant to AE&E. He
has more than 36 years of experience as a geotechnical engineer on a variety of projects onshore and
offshore in Alaska, California, and Guam. He has special training and experience in arctic engineering,
engineering geology, and coastal and earthquake engineering. Mr. Miller has provided geotechnical
engineering services on architectural, civil, mining, petroleum, and military projects across Alaska since
1973 and has worked extensively with the Authority and AE&E.
Electric Power Research Institute
Roger Bedard, M.E., EPRI, will serve provide RISEC Technical Consulting. He has more than 40
years of engineering R&D experience, focused recently on emerging energy systems. He will work with
the Project Manager to bring his and EPRI’s expertise in renewable energy, in-stream river and tidal
power, to the team. He has been the EPRI Ocean Energy leader since 2004 and managed in-stream
projects across the continent and several in Alaska, including the RISEC study in Igiugig that is the
foundation for this proposal. His EPRI Ocean Energy Program has accelerated the deployment and
commercial development of in-stream renewable resource technologies. He and its engineers together
have published more than 18 public reports on various aspects of tidal energy conversion, including
resource assessments, conceptual design studies, environmental effects, cost and economics.
Mirko Previsic, P.E., EPRI/re-vision LLC, will provide RISEC Technical Consulting from his 10
years of experience with the design, evaluation and optimization of renewable power generation systems,
theoretical modeling, resource assessments, feasibility studies, and environmental impact studies with an
emphasis on wave and tidal power conversion. He has had primary technical responsibility in many high-
profile studies of wave, tidal and river-in-stream power conversion for various state and federal
government agencies, research institutes, technology development companies and utilities. He is the
Technology Lead in the RISEC projects for EPRI Ocean Energy programs and was instrumental in the
baseline RISEC study in Igiugig.
Bristol Bay Science and Research Institute
Michael Link, BBSRI executive director, will develop the Environmental Monitoring plan,
perform and evaluate fisheries studies, and interface with the Alaska Department of Fish and Game. He
has spent two decades designing and implementing fisheries research and management programs in
Alaska and western Canada. BBSRI is an independent research institute established in 1999 by Bristol
Bay Economic Development Corporation to undertake research and education to lead to a greater
understanding of the fish stocks, fisheries, and the environments of the Bristol Bay region. Mr. Link leads
the interdisciplinary team to improve management of area fish stocks and to increase participation by
locals by establishing in-house expertise and knowledge.
Igiugig Village Council
Igiugig Village Council has an extensive Infrastructure. The community has a 3,300-foot airport
Renewable Energy Fund
Grant Application
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runway with AWOS and GPS approach. Barge service via Bristol Bay is available August through
September most years. The community is barge-accessible for Anchorage/Kenai/Homer May through
October via the Pile Bay/Williamsport Road, and across Lake Iliamna all years. The IVC owns a 30’ x
80’ FlexiFloat flat deck barge capable of carrying 225,000 pounds and distributes 90% of non fuel-related
goods for all the communities and businesses of the Lake Iliamna region. Local residents have multiple
32’x13’ aluminum 450HP plus diesel-powered fishing boats that pull or push the FlexiFloat when needed.
Many power skiffs ranging from 18’ to 24’ and 80 to 150HP are available as well to assist in any
potential installation and/or operational activities.
Iliamna Lake Contractors, LLC
Igiugig Village Council is an owner of a Tribal Heavy Construction Firm, Iliamna Lake
Contractors LLC, and has access to a large inventory of heavy equipment that is fully operational, modern
and well maintained, including:
• Cat 330 and 320 excavator
• Cat 966 and 950 loaders, buckets and forks
• 10 yard cement truck and fill hopper
• Cat 163 grader and JD 572 grader
• Numerous 10/12 yard end dumps, 20 yard Cat D300E articulating dump
• Plasma cutter/welders, aluminum, steel, etc.
• Cat D7, Cat D6, Cat D4, 2 JD 450 dozer/backhoes
• 40’ boom truck, 15,000 lb. crane
• Numerous light and heavy power tools, winches, etc.
All of the above can operate off of FlexiFloat barge.
RISEC technology provider
RISEC technology vendors will be selected based on a competitive RFP process tailored specifically
to the characteristics of the Igiugig project.
The project will be constructed using primarily utility and local force account labor. Locally available
contractors will be used for the assembly and installation of the RISEC modules. All major purchases and
construction contracts will be in accordance with the Village of Igiugig procurement policies.
Our proposed organization chart (below) for this project introduces and identifies key members of our
team and shows the lines of authority. Each engineering discipline is led by a professional engineer
registered in the State of Alaska. All engineering documents will be stamped by Alaska registered
engineers.
Refer to Appendix A for resumes of key personnel
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3.5 Project Communications
Discuss how you plan to monitor the project and keep the Authority informed of the status.
Alaska Energy and Engineering is in communication with AEA staff on almost a daily basis on a variety
of active projects. The Authority Project Manager will be kept up to date on the RISEC pilot project
status by periodic email and/or verbal status reports, in addition to written quarterly reports that will be
submitted by the Village of Igiugig Grant Manager. Periodic reports will provide general information
regarding project status and any unforeseen circumstances that need to be resolved. The quarterly reports
from the Grant Manager will include specific information on project completion status vs. project
schedule; project labor reports – including hours, rates and costs; and current project expenditures relative
to budgeted project costs.
In addition to regular email updates and quarterly reports, we also propose to conduct a minimum of four
briefings:
• an initial kickoff briefing of the detail project implementation plan,
• a mid term review at the completion of the Phase II Pilot Project,
• a review at completion of final design and permitting,
• and a final briefing of all project results.
AE&E has provided design and construction support services on over 80 energy infrastructure-related
projects throughout Alaska over the past 15-years. Our long-term working relationship with the Authority
assures well-tested monitoring methods and seamless channels of communication.
3.6 Project Risk
Discuss potential problems and how you would address them.
The risk associated with this project to develop emerging RISEC technology will be mitigated by
implementing a risk identification and mitigation program for the duration of the project. At this proposal
stage, the primary risks and our proposed mitigation plan are as follows:
1. Risk of increased project cost – the cost estimate to construct and operate the commercial plant is
currently at the preliminary design stage of development. There is a risk that the cost estimate
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will increase during the final design and permitting stage of development. This risk will be
mitigated by the development and testing performed during the Pilot Project phase, by deferring
selection of a RISEC technology provider until the final Phase IV, and by developing a concise
and specific RFP solicitation for selecting the final technology provider.
2. Risk of measurable environmental affects – As RISEC technology is emerging; there is currently
uncertainty about interactions between the RISEC turbines and the environment in which they are
generating electricity. The primary purpose of a pilot plant is to gain technical, environmental,
and commercial confidence in a technology. To minimize risk and maximize the outcome of this
RISEC pilot project, the Village of Igiugig is enlisting the services of Bristol Bay Science and
Research Institute to develop a study plan to identify the horizontal and vertical turbines’ effects
on the spring out-migration of smolt and summer return of adult fish. Environmental effects will
be monitored and mitigated, if possible, or the RISEC turbines will be pulled from the water.
There are additional elements of risk that arise in any rural Alaska construction project; however, the risk
associated with this project is well managed. A highly competent team of professionals has been
assembled with the skills and motivation necessary to see this project through to successful completion.
The project has been devised to proceed in distinct phases, with carefully planned go/no go decision
intervals. In the event that the pilot project is deemed unsuccessful, or the Village of Igiugig changes its
direction or power production needs, the latter phases of the project may be postponed or cancelled with
little additional risk.
IVC understands the potential risks from this project, but seeks to be an early adopter of RISEC
technology and realize the benefit of reduced diesel fuel consumption by utilizing a readily available
renewable resource. Demonstration of increased cost certainty and minimal environmental effects of this
technology at Igiugig will benefit many remote villages in the state of Alaska. IVC is willing to accept
these risks.
SECTION 4 – PROJECT DESCRIPTION AND TASKS
• Tell us what the project is and how you will meet the requirements outlined in Section 2 of
the RFA. The level of information will vary according to phase of the project you propose to
undertake with grant funds.
• If you are applying for grant funding for more than one phase of a project provide a plan and
grant budget for completion of each phase.
• If some work has already been completed on your project and you are requesting funding for
an advanced phase, submit information sufficient to demonstrate that the preceding phases
are satisfied and funding for an advanced phase is warranted.
4.1 Proposed Energy Resource
Describe the potential extent/amount of the energy resource that is available.
Discuss the pros and cons of your proposed energy resource vs. other alternatives that may be
available for the market to be served by your project.
The current in the Kvichak River that flows past Igiugig is a renewable resource identified as one of the
prime sites in Alaska for a pilot demonstration project of River In-Stream Energy Conversion. In Phase I
Reconnaissance studies done by EPRI, we found that the river’s discharge rates and related power-
densities at Igiugig are more consistent year-round than the typical summer peak found in other rivers.
Lake Iliamna, the Kvichak’s source, smoothes the summer/winter variability. The pilot demonstration
project will start with up to 10kW of RISEC turbines. The commercial RISEC plant is expected to be rated
at least 40kW to meet the communities community’s base electric load.
The river is relatively shallow and velocities are highest in the middle of the channel and near the surface.
The water depth at the site of interest will likely limit the rotor size to 1.5m. Unlike areas farther
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downstream, this portion of the river remains ice-free during the winter. During spring breakup of Lake
Iliamna (about two weeks) and during occasional wintertime wind-driven lake ice releases, the turbines
would need to be removed to protect them from ice chunks.
There does not appear to be another more viable energy alternative to RISEC power, at this time. Although
the R&D costs associates with the development of the pilot project are relatively high, the implementation
costs of the commercial RISEC plant are anticipated to be relatively low, since the existing community
powerhouse and electric distribution system are located within 200 feet the river/hydro source.
The Kvichak River bed is believed to consist of a fine silt base and an overburden of cobbles, rocks and
gravel, depending on current and location of river width. Directly adjacent to the powerhouse the river
expends its greatest velocity and/or gradient as it leaves Lake Iliamna and winds down the “cut-bank.” The
riverbed here is characterized by rocks approximately 6”- 12” in diameter interlaced with stones, sand, and
gravel for a protective barrier to the underlying silts. River width at this location is approximately 437 feet.
River depth raises approximately 4 to 6 feet in depth May through October with temporary wind-driven
increases of an additional 6” to 2’. Greatest depths occur in late fall (September/October) and lowest depth
after ice cover loss on Lake Iliamna in April/May.
The following illustration shows the water velocity readings taken on June 20, 2007. Detailed river cross-
sectional profile and the depth averaged velocity measurements will be performed at the early stages of the
Pilot Project to determine the optimum RISEC location and to develop the RFP specifications.
Given that water depth will be the limiting factor on rotor diameter, it is possible that the total number of
installed rotors for a commercial installation could range from a dozen to more than twice that number,
depending on the plant rating scenario chosen. A high penetration design scenario would likely result in a
RISEC installation with a total peak output of around 40kW.
Total river freeze-over is rare at this location and usually requires a freeze/thaw/wind event to push ice out
of the lake and fill the river. Twenty-five years of local experience estimates that this portion of the river is
frozen over completely less than two weeks of the year. Some years no ice has formed or discharged down
1’: 3.41fps
4’: 4.26fps
6’: 4.21fps
box A
1’: 7.42fps
4’: 6.39fps
8’: 5.47fps
box B
1’:4.90fps
4’:4.98fps
5’:4.30fps
box C
Distances:
• from shore to readings in boxes a
and d is 15’
• from boxes a and d to readings in
boxes b and e is 100’
• from boxes b and e to readings in
boxes c and f is 130’
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the Kvichak. Spring breakup usually occurs March through May, with ice passage lasting approximately
two to three weeks. Thickness of passing ice ranges from 3” to 4’. Final commercial design will
incorporate methods to protect the RISEC system from potential ice damage.
Water clarity is extremely high during periods of calm wind with visual bottom observation possible at 10
feet or more. Prevailing east winds may increase turbidity with organics and silt, but these readily settle
depending on direction and change of wind speed. The Kvichak River has little to no large debris, as
sparse vegetation and its close proximity to the outlet doesn’t allow these obstructions to accumulate. The
west end of Lake Iliamna is virtually free of large debris.
The Kvichak River is a navigable waterway that allows a range of marine traffic from a skiff to a LCM
barge that may draw up to 8’. Directly adjacent to the powerhouse, traffic is minimal due to the heavy
current and lack of infrastructure requiring access. The USGS maintains a stream gauging station on the
Kvichak River at Igiugig (Station# 15300500 Kvichak River at Igiugig), with 21 years of daily discharge
records over the period between 1966 and 1987. That data was used to establish a data set suitable for
evaluating RISEC technology. First a relationship between discharge rate and velocity was established;
that relationship function was then applied to the full data set to determine the statistical parameters shown
below.
It is important to note that the velocity profiles and associated power densities below are valid for the
USGS station site, which was used to calibrate the flow and velocity data for the EPRI Reconnaissance
level assessment (refer to Appendix F).
USGS Station Summary
Station Name: Kvichak River at Igiugig, AK
Station ID: 15300500
Lake And Peninsula Borough, Alaska
Hydrologic Unit Code 19030206
Latitude 59°19'44", Longitude 155°53'57"
Drainage area 6,500.00 square miles
Gage datum 45.00 feet above sea level
Resource Data Overview
Velocities Unit
Average Velocity m/s 1.41
Average Mid-Channel Velocity m/s 1.84
Power
X-Section Average Power Density kW/m^2 1.48
Mid-Stream Average Power Density kW/m^2 3.24
Average Total Kinetic Power kW 719
Dimensions (During Typical Discharge Conditions)
Discharge Rate for Referenced Dimensions m^3/s 487
Cross-Section m^2 365
Width m 152
Average Depth m 2.4
Deepest Point m 3.7
Discharge
Average m^3/s 507
Maximum m^3/s 1,277
Minimum m^3/s 181
Maximum Stage Differential mNA
During the first step of Phase II, an acoustic doppler current profile (ADCP) of the proposed RISEC
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location will be performed to identify “hot spots” where the river velocity is greatest, and to correlate the
historical USGS streamgauge data to the site. The short term ADCP measurements will support
extrapolation of the historical USGS data to provide a realistic annual flow profile at the selected RISEC
site without the need for multiple years of local velocity measurements.
4.2 Existing Energy System
4.2.1 Basic configuration of Existing Energy System
Briefly discuss the basic configuration of the existing energy system. Include information about
the number, size, age, efficiency, and type of generation.
The Village of Igiugig has three diesel-powered generators ranging from 60 to 100kW that work
independently of load, as necessary, to energize the community’s 7200-volt, three-phase distribution
system. The generators were installed in a two-phased program in 1998 and 2002.
The Alaska Energy Authority has prepared a conceptual design report for a powerhouse, power
distribution and generation heat recovery system upgrade at Igiugig. The following proposed upgrades will
modernize the existing Igiugig power plant and improve the overall fuel efficiency, reliability, fire
prevention/protection and operations at the facility:
• Replace all three existing generators utilizing marine jacketed units for maximum generation heat
recovery.
• Replace existing switchgear and relays with new programmable automatic paralleling switchgear
with load sharing capabilities set up for possible integration of alternative energy generation.
• Remove existing siding/roofing and interior fiberglass batt insulation and replace with new
insulated sandwich panels.
• Install new interior mounted critical grade silencers on all three generators.
• Replace existing ventilation equipment with sound-insulated air intake and exhaust fan ducting.
• Install new radiators with variable speed motor controls, to minimize station service power
consumption.
• Replace existing engine coolant manifold and heat recovery system, including thermostatic valve,
brazed plate heat exchanger for improved efficiency. Install energy meter for system monitoring.
• Install new fire detection and suppression system.
• Provide sound insulated control room with personnel heater.
• Reuse existing fuel supply pipeline, day tank and control panel.
The upgrade is expected to include new Tier II marine gensets and auto synchronized switchgear that
monitors loads and integrates proper generator set capacity and operation per load requirement. Design
engineers are evaluating alternative energy upgrades in the powerhouse design to ensure cost-efficient
implementation and to support integration of a RISEC project.
The IEC power plant has been the sole source of power generation for Igiugig and it is anticipated it will
continue to be the prime power source even as other alternative energy projects are developed.
4.2.2 Existing Energy Resources Used
Briefly discuss your understanding of the existing energy resources. Include a brief discussion of
any impact the project may have on existing energy infrastructure and resources.
Diesel fuel is delivered to Igiugig by barge in summer and stored in bulk at a tank farm adjacent to the
powerhouse. The proposed RISEC project will displace diesel fuel but will not completely replace the
diesel generation capability. The RISEC system will be sized to provide sufficient energy for the lowest
load day of the year. Diesel generation will be used for load following.
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4.2.3 Existing Energy Market
Discuss existing energy use and its market. Discuss impacts your project may have on energy
customers.
A power recorder was installed in the Igiugig power plant in December 2007 to gather community power
demand data for the RPSU project design. Data from this recorder was downloaded in September 2008.
The data shows a winter peak daily load of around 52kW in January 2008 and the summer peak daily load
of around 42kW in June 2008.
Steady growth in Igiugig's summer peak loads and annual generation are likely over time due to expected
increases in tourism as well as planned new developments including a clinic, water treatment plant and
subdivision development.
In 1983 IEC successfully supplied power to several lodges near Igiugig after installing a submarine cable
across the Kvichak River directly below the power plant. However the cable was left in during the winter
and was damaged by lake ice in the spring and has not been replaced. These lodges have recently
approached IEC about resuming this service. With better boats and equipment available in the community
now, IEC is considering a seasonal service with the submarine cable removed each year prior to freeze-up.
It is projected that this additional seasonal load would cause summer peak and monthly demand to
approach the current winter loads.
Based on these factors, it is estimated that annual generation requirements will grow to over 250,000kWH
and peak demand loads will reach 75kW or more within five years.
A successful commercial RISEC installation and a corresponding decrease in local electricity rates could
encourage both public and private facilities to increase the use of electric space heating in the future,
potentially increasing peak demand and further increasing annual generation requirements.
4.3 Proposed System
Include information necessary to describe the system you are intending to develop and address
potential system design, land ownership, permits, and environmental issues.
4.3.1 System Design
Provide the following information for the proposed renewable energy system:
• A description of renewable energy technology specific to project location
• Optimum installed capacity
• Anticipated capacity factor
• Anticipated annual generation
• Anticipated barriers
• Basic integration concept
• Delivery methods
The Phase I Scoping Brief and RISEC Reconnaissance level feasibility study, and Task 1 Energy
Assessment of Phase II have been completed, refer to Appendix F for detailed information.
Phase II - Pilot Demonstration Project
Building on information gathered in the prior Phases, this phase will establish the project configuration
and specifications that will be used to guide construction, refine project cost estimates, finalize business
plans, and obtain land use and resource authorizations required for construction. Work shall address the
information and tasks below.
Task II.2 - Energy Resource Assessment
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An acoustic doppler current profile (ADCP) and bathymetric survey of project site and preliminary
Geotechnical evaluation will be performed. The ADCP will provide specific river flow information to
select the preferred RISEC installation site, and the bathymetric survey will provide a contour map of the
river bottom. Analysis of ADCP/ bathymetric data will be used to develop specific performance
specifications for the RISEC pilot devices. A preliminary geotechnical evaluation will also be performed
at this time using acoustic technology to probe and assess the river bottom conditions.
Task II.3 - RISEC Pilot Device Design/Solicitation
RISEC devices are at a very early stage of development. To carry out the prior Reconnaissance level
performance, cost, and economic assessments, EPRI established a baseline device design consisting of
open rotor horizontal axis turbines mounted on a pontoon structure. The pilot project RISEC equipment;
however, will be tailored specifically to the Igiugig application using results of the Kvichak River acoustic
doppler current profile, bathymetric survey, and preliminary geotechnical research. We will develop and
submit to qualified vendors an RFP based specifically on the Igiugig RISEC parameters. It is anticipated
that the pilot project RISEC device will have a 10kW maximum output. The RFP will require the
manufacturer to provide the recommended structural support elements (pontoons) for this phase of the
project.
Due to the relatively high cost of developing and monitoring a RISEC pilot project in remote Alaska,
compared to the RISEC equipment purchase cost, the pilot project will select and test two different RISEC
technologies in a side-by-side evaluation. The purpose of this dual-effort is to identify potential differences
in electro-mechanical performance, as well as possible differences in environmental impact. The initial
focus will be to the preliminary selection of one horizontal axis and one vertical axis RISEC power unit
for pilot project.
Task II.4 - RISEC Pilot Project License, Permitting and Fish Impact Study Design
An application for a FERC hydrokinetic pilot project license is currently underway. Bristol Bay Science
and Research Institute (BBSRI) will provide a biologist and a technician to work with IVC to develop a
specific and detailed fish impact study plan based on selected RISEC pilot device configurations. The
NEPA project level environmental review will also be initiated and comments solicited for federal and
state regulators and project stakeholders.
Task II.5 - Procure and Deploy RISEC Pilot Devices
Upon completion of the pilot project license and permitting requirements, and review of proposed RISEC
technologies, two RISEC pilot devices will be selected and procured for installation and testing. This task
will also include specifying, procuring and installing the wireless remote RISEC performance
monitoring/SCADA equipment, current measurement devices and load banks for installation on the
RISEC pilot devices. Materials will be specified and procured for RISEC anchoring systems. All materials
will be purchased FOB Homer, barged to Pile Bay on the west shores of Cook Inlet at Kamishak Bay, then
trucked over Pile Bay Road to Williamsport on the eastern shore of Lake Iliamna. Materials will then be
freighted by ILC flexi-float to Igiugig for installation.
Upon arrival in early spring, the RISEC pilot devices will be assembled and the outfitted with the load
bank and telemetry equipment. The anchoring systems will be fabricated and the RISEC pilot devices
deployed utilizing local equipment and flexi-float barge. The RISEC pilot devices will then be
commissioned and wireless remote performance monitoring of the electro-mechanical systems will begin.
Task II.6 - Smolt and Adult Fish Impact Studies
The Bristol Bay Science and Research Institute (BBSRI) will provide a biologist, technician and other
support staff as required to conduct a single season fish impact study. The study will use side-looking
imaging (DIDSON) sonar, single-beam up-looking sonar arrays, net sampling and physical observation to
evaluate the response of juvenile and adult salmon to the deployed pilot RISEC devices. Field data will be
compiled and a fish impact study report will be completed for both RISEC pilot devices.
Task II.7 - Conduct RISEC Pilot Project Remote Performance Monitoring
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Coincident with the fish impact study, daily RISEC pilot device performance and river current data will be
collected. During this timeframe, periodic on-site inspections and maintenance of RISEC pilot devices will
be performed. It is expected the RISEC units will remain in the water until late fall, when the risk of
damage from lake ice increases.
RISEC pilot device electro-mechanical performance data will be compiled and assessed and final
performance reports will be prepared and issued.
Task II.8 - Preliminary Analysis & Recommendations
The Igiugig team will perform comprehensive financial, performance and environmental analysis of the
RISEC technologies tested. Careful consideration will be given to address performance vs. assessed
environmental affects. After careful evaluation of all aspects of the project, a Go/No-go decision will be
made for the commercial scale RISEC power project in Igiugig.
Presuming a Go decision is reached, performance specifications and structural element conceptual design
for the commercial scale RISEC project will be finalized. It is anticipated that sufficient geotechnical data
can be acquired using echoic methods during the pilot project river current and bathymetry phase to
support detailed conceptual design. Due to the anticipated high cost of performing a full geotechnical
evaluation of the river floor using conventional drilling techniques, the final geotechnical study will not
take place until after a Go decision has been reached. The process of producing a draft business and
operational plan will be initiated at this step.
PHASE III. FINAL DESIGN & PERMITTING
Task III.1 - RISEC Commercial Installation Design/Solicitation
Due to AE&Es ongoing involvement with the energy infrastructure in Igiugig over the past 10 years, we
have detailed record data of the Igiugig powerhouse and electric distribution systems for coordination with
the RISEC commercial scale project. A thorough analysis of current and potential near-term future
electrical use within the community will be conducted and compared to potential RISEC capacity
scenarios based on the analysis of the ADCP and bathymetric data collected. This information will be used
to determine the total RISEC capacity and design that will provide the optimum project cost/benefit. A
grid integration study will be completed and the conceptual design advanced to approximately 65%. Once
sufficient design detail has been developed, the geotechnical investigation for proposed commercial
RISEC installation will proceed.
A RFP for the commercial RISEC equipment will be prepared and submitted to manufacturers based on
final performance specifications, structural element conceptual design, geotechnical investigation and grid
integration design. It is anticipated that at this juncture, a single RISEC technology vendor will be selected
for the RISEC power units for the commercial project.
Task III.2 - Permitting & Site Control for RISEC Commercial Installation
In conjunction with the RFP development, and immediately after the Go decision has been reached, final
application to FERC for a hydrokinetic license will be made, along with the commercial scale NEPA
environmental review process, including Alaska Coastal Management, Corps of Engineers, Fire Marshal,
and other state and federal regulatory agencies. Site control requirements will also be confirmed and site
control secured as required for the RISEC commercial project.
Task III.3 - Project Cost and Benefits
A final cost estimate for RISEC commercial installation project will be developed and sufficient funding
and resources verified prior to moving forward with construction of the commercial plant. A detailed cost
benefit analysis will be performed based on final construction costs and the performance data acquired
during the pilot project
Task III.4 - Final Analysis & Recommendations for Commercial Installation Project
All site control, funding, and the business operating plan will be finalized. A report will be prepared and
issued detailing the final design recommendations, estimated construction costs, construction plan and
schedule.
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PHASE IV. CONSTRUCTION, COMMISSIONING, OPERATIONS & REPORTING
Task IV.1 - Construction Scheduling & Procurement
The commercial RISEC power units, as well as grid integration equipment, switchgear, power cables, and
all other required construction materials will be procured and consolidated in Homer, Alaska for shipment
via the Pile Bay road to Igiugig. Throughout the procurement and construction, actual project costs will be
tracked against budgeted costs to ensure the project stays on budget. Contract(s) will be negotiated for on-
site construction or off-site fabrication of the structural element(s) depending on whether a pile-based or
pontoon-based design is selected for the commercial RISEC installation.
Task IV.2 - Construction Mobilization
Materials, equipment and tools, including pontoons and anchoring hardware if required for RISEC
installation, will be barged to Pile Bay and trucked over Pile Bay road to Williamsport on Lake Iliamna.
The ILC Flexi float will be used to mobilize materials and equipment across Lake Iliamna to Igiugig.
If a pile-based structural element is incorporated into the design, all equipment, piles, supplies and crew
required for pile installation will be transported by barge up the Kvichak River to Igiugig in early spring or
as soon as river conditions allow. ILC will provide locally based crews for both the RISEC deployment
and the grid integration portions of this project so no crew mobilization/ demobilization will be required
for this portion of the project.
Task IV.3 - RISEC Installation & Commissioning
After the delivery/installation of all required structural elements, equipment and supplies, ILC crews and
RISEC device technical support personnel will field assemble and deploy the RISEC devices. The ILC
line crew will install and connect all grid integration equipment and cable interties.
Upon completion of installation EPRI, AE&E and AEA personnel will supervise the commissioning of the
RISEC plant, including load bank testing to verify system output, testing of dump-load system if required,
demonstration of automatic paralleling capabilities with existing diesel generation, remote monitoring /
SCADA system functionality, and testing of all required protective devices.
Task IV.4 - Environmental Monitoring of Final RISEC Installation
BBSRI will provide a biologist and technician to conduct an abbreviated fish study during the first salmon
run following the commercial RISEC installation. This study will employ the same methodology and sonar
equipment used for the pilot phase fish impact study in order to verify that the response of juvenile and
adult fish to the commercial RISEC installation is as predicted.
After all final environmental data is gathered, BBSRI and AE&E will issue all final environmental reports
required by the permitting agencies, including FERC, ADF&G and others.
Task IV.5 - Analysis & Recommendations
Upon project completion the business plan will be updated and the RISEC power rate will be recalculated
based on actual project costs. A final RISEC project report will also be issued, complete with as-built
drawings, O&M manual, a project analysis and final recommendations.
EPRI will continue to remotely monitor the Igiugig RISEC system for at least three years following the
completion of the project in order to provide a long term performance evaluation of the RISEC technology
employed and to determine the overall benefits to the community.
4.3.2 Land Ownership
Identify potential land ownership issues, including whether site owners have agreed to the
project or how you intend to approach land ownership and access issues.
The power plant site is entirely contained within Tract H-2, Igiugig Community Facilities Subdivision.
The surface estate of Tract H-2, power plant site, is owned by the State of Alaska, Department of
Community, Commerce and Economic Development, in trust for a future city in Igiugig. The Igiugig
Village Council has a long-term lease from the State for the power plant site.
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The proposed RISEC hydroelectric site is located near the south shore of the Kvichak River in the "cut
bank" area directly adjacent to the IEC power plant, approximately 0.2km below the outlet of Lake
Iliamna. Site access requirements will be investigated with the State of Alaska, Department of Natural
Resources, as part of the Pilot Project preliminary permitting effort.
4.3.3 Permits
Provide the following information as it may relate to permitting and how you intend to address
outstanding permit issues.
• List of applicable permits
• Anticipated permitting timeline
• Identify and discussion of potential barriers
The proposed RISEC project is subject to regulations of both State and Federal agencies including the
Alaska Coastal Management Program, the Alaska Department of Environmental Conservation (ADEC),
the U.S. Environmental Protection Agency, U.S. Coast Guard, U.S. Army Corps of Engineer, Alaska
Department of Natural Resources (DNR), Alaska Department of Fish and Game (ADF&G) and the
Federal Energy Regulatory Commission (FERC) regulations as well as tideland survey requirements.
FERC has recently adopted the Hydrokinetic Pilot Project Licensing Process to define and streamline
permitting requirements for these projects during pilot plant operation, testing and monitoring. In addition
to the FERC licensing process, a NEPA project level environmental review will be performed to
demonstrate and confirm the project will not have a negative impact on the human environment. There are
no wetlands in the project area, an evaluation will be made to ensure there are no known archaeological or
historic properties within the area of potential effect, and that no birds or mammals listed as endangered or
threatened that will be impacted by the project. It is anticipated the FERC and NEPA environmental
review for the pilot project will be completed by the second quarter of 2010.
Should the project advance to commercialization, final FERC license and project permitting is anticipated
to be completed in the 1st quarter of 2013.
4.3.4 Environmental
Address whether the following environmental and land use issues apply, and if so how they will
be addressed:
• Threatened or Endangered species
• Habitat issues
• Wetlands and other protected areas
• Archaeological and historical resources
• Land development constraints
• Telecommunications interference
• Aviation considerations
• Visual, aesthetics impacts
• Identify and discuss other potential barriers
Environmental Considerations
The Kvichak River supports populations of all five species of Alaska Salmon, as well as an abundant stock
of Rainbow Trout, Grayling, Dolly Varden, Whitefish, Pike, Ling Cod, and others. Annual smolt
outmigration generally occurs in May/June for approximately three weeks, with peak passage occurring in
the cover of nightfall. Adult salmon return to spawn from mid-June to mid-July.
The primary environmental concern is expected to be fish migration and spawning habitat. None of the
fish are endangered or threatened, but salmon and salmonid species such as trout are vital economically
and culturally to the region. The effects of RISEC machine/rotors on anadromous fish is unknown. Bristol
Bay Science and Research Institute (BBSRI) will develop and conduct monitoring studies using side-scan
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 22 of 25 9/3/2008
sonar, bottom sonar arrays and net sampling for migrating young smolt from May 15 to June 15. Similarly,
BBSRI will monitor any effects on adult fish using observers in shore tower, underwater videography, and
side-scan sonar from June 15 to July 15 during the pilot study and again during commercial RISEC
installation. Mitigation efforts to deflect fish passage, removal or shutdown of equipment may be required
to manage potential conflicts.
AE&E has provided NEPA project level environmental permitting on over 40 energy related projects
throughout Alaska during the past 10 years. Our understanding of the NEPA process and potential
environmental impacts of our projects allows us to mitigate possible negative affects early in the design
stage. Environmental permitting for the pilot project is anticipated to be completed by spring of 2010.
4.4 Proposed New System Costs (Total Estimated Costs and proposed Revenues)
The level of cost information provided will vary according to the phase of funding requested and
any previous work the applicant may have done on the project. Applicants must reference the
source of their cost data. For example: Applicants Records or Analysis, Industry Standards,
Consultant or Manufacturer’s estimates.
4.4.1 Project Development Cost
Provide detailed project cost information based on your current knowledge and understanding of
the project. Cost information should include the following:
• Total anticipated project cost, and cost for this phase
• Requested grant funding
• Applicant matching funds – loans, capital contributions, in-kind
• Identification of other funding sources
• Projected capital cost of proposed renewable energy system
• Projected development cost of proposed renewable energy system
The cost information provided in this application is a composite of a variety of sources, including
engineers estimates, budget proposals for geotechnical and bathymetry efforts, cost data from EPRI’s prior
projects, and AE&E’s 15-years of successfully designing and constructing energy related projects
throughout Alaska. The hands-on construction management of our projects helps keep us current with ever
escalating construction costs.
Total anticipated project cost: $2,396,830
Phase II (Pilot Project): $ 718,175
Phase III (Commercial Design / Permitting): $ 443,038
Phase IV (Commercialization and Monitoring): $1,226,418
Requested grant funding: $2,302,630
Applicant matching funds –
loans, capital contributions, cash: $ 50,000
Identification of other funding sources: IVC
Projected capital cost of renewable energy system: $2,396,830
Development cost (phases II &III): $1,161,213
4.4.2 Project Operating and Maintenance Costs
Include anticipated O&M costs for new facilities constructed and how these would be funded by
the applicant.
• Total anticipated project cost for this phase
• Requested grant funding
The O&M costs for a RISEC project are as yet unknown because currently there are no commercial- scale
RISEC projects in operation. This proposal’s goal is to implement a pilot project to ferret out real costs
based on remote Alaska application. Although the specific costs associated with operating and maintaining
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 23 of 25 9/3/2008
a RISEC plant are unknown, the AE&E team has continually demonstrated its ability to use innovative
technologies throughout rural Alaska that are highly cost effective and that result in low O&M costs. A
significant component of the pilot project is to confirm that the benefits of this renewable resource are not
discounted due to poor reliability and high operational costs.
Real O&M costs obtained during the pilot project will be incorporated into the business plan at Phase III
and will weigh heavily in the decision to advance the pilot project to commercialization under Phase IV.
4.4.3 Power Purchase/Sale
The power purchase/sale information should include the following:
• Identification of potential power buyer(s)/customer(s)
• Potential power purchase/sales price - at a minimum indicate a price range
• Proposed rate of return from grant-funded project
IVC is the electric utility and project operator; therefore, there will be no power purchase agreement.
Due to the infancy of this technology and many unknowns yet to be determined during the pilot project,
the cost of power from RISEC technology is unknown.
Refer to attached EPRI reconnaissance level report in Appendix F for more information.
4.4.4 Cost Worksheet
Complete the cost worksheet form which provides summary information that will be considered
in evaluating the project.
Download the form, complete it, and submit it as an attachment. Document any conditions or sources
your numbers are based on here.
The cost worksheet is submitted as an attachment, refer to Appendix B.
4.4.5 Business Plan
Discuss your plan for operating the completed project so that it will be sustainable. Include at a
minimum proposed business structure(s) and concepts that may be considered.
Once this RISEC pilot project has been demonstrated commercially viable, a draft Business Plan will be
prepared and completed during Phase III, final design and permitting of the commercial scale project. IVC
is currently preparing a Business Operating Plan for its RPSU powerhouse upgrade project and has the
resources and ability to integrate the RISEC project into its operating assets. AE&E has assisted
communities in preparing Business Plans for over a dozen AEA/Denali Commission projects.
4.4.6 Analysis and Recommendations
Provide information about the economic analysis and the proposed project. Discuss your
recommendation for additional project development work.
The EPRI reconnaissance level feasibility study includes a simple payback period calculation for
an assumed built out commercial scale plant for a remote grid scenario, refer to Appendix F.
Renewable Energy Fund
Grant Application
AEA 09-004 Grant Application Page 24 of 25 9/3/2008
SECTION 5– PROJECT BENEFIT
Explain the economic and public benefits of your project. Include direct cost savings,
and how the people of Alaska will benefit from the project.
The benefits information should include the following:
• Potential annual fuel displacement (gal and $) over the lifetime of the evaluated
renewable energy project
• Anticipated annual revenue (based on i.e. a Proposed Power Purchase Agreement price,
RCA tariff, or avoided cost of ownership)
• Potential additional annual incentives (i.e. tax credits)
• Potential additional annual revenue streams (i.e. green tag sales or other renewable
energy subsidies or programs that might be available)
• Discuss the non-economic public benefits to Alaskans over the lifetime of the project
The Igiugig pilot project will advance the technical design, permitting, and environmental knowledge of
RISEC for use by other Alaskan communities considering this form of renewable energy. The project will
also boost the expertise of the industry and potentially reduce manufacturing and operations costs.
Economic benefits
The estimated annual fuel displacement from a 40kW commercial scale project is 15,000 gallons/year.
This equates to approximately 300,000 gallons over a twenty-year anticipated useful life of the project.
The anticipated cost savings to the electric utility based on reduced diesel fuel use is $85,000 per year
based on the current fuel cost of $5.67/gallon.
Non-economic benefits
There are no known tax credits or other subsidies for a project of this type.
Non-economic benefits to Alaskans include the reduction in diesel exhaust emissions realized by using a
renewable RISEC resource, short term job creation during testing and construction, as well as the
improved long term viability of the Igiugig utility.
SECTION 6 – GRANT BUDGET
Tell us how much your total project costs. Include any investments to date and funding sources,
how much is requested in grant funds, and additional investments you will make as an
applicant.
Include an estimate of budget costs by tasks using the form - GrantBudget.xls
Provide a narrative summary regarding funding sources and your financial commitment to the project.
Total estimated project cost is $2,396,830. The grant request for all three phases is $2,302,630. IVC will
provide a cash match in the amount of $50,000, in addition to heavy equipment provided as a contribution
in aid of construction. Refer to Grant Budget worksheet in Appendix C
~)ALASKAI~:'tI'lIiH,"Y A,lJTHIJRlTY
Renewable Energy Fund
Grant AppJJcatlofl
!,I$Ecffq~':i~,.!.Qi~I~!~~L,~:C>9YMeNT~Tlq~~:~b.:eR"l·~J~~o."'·.'",""..
I,.:.'',..E.,:,,:,.,.·;~jP~M'~t~~FQ~LOWINGI:)()9u"'E~TS'~IT~yqp~~~PL~;CA.!J9N:'.,',.'j
A.Resumes of Applicant'$Project Manager,kay $taff,partn9rs.consultants,and
suppliers per application form Section 3.1 and 3.4
B.Cost Worksheet per application form Section 4.4.4
C.Grant SUdget Form per application form Section 6.
D.An electronic version of the entire application per RFA Section 1.6
E.Governing Body Resolution per RFA Section 1.4
Enclose a copy of the resolution or other formal action taken by the applicant's
governing body or management that:
authorizes this application for project funding at the match amounts indicated in
the application
authorlze5 the individual named a5 point of contact to represent the applicant for
purposes of this application
State5 the applicant is In compliance with aU federal state.and local,laws
including ~xi$ting credit and f8d&ral tax obligations.
F.CERTIFICA liON
The undersigned certifies that this application for a renewable energy grant is truthful
and correct,and that the applicant is in compliance with,and will continue to comply
with,all federal and state laws Including existing credit and federal tax obligation5.
..•.
I AEA 09-004 Grant Application
l("
Page 25 of~
APPENDIX A
PROJECT RESUMES
Home Company Overview Services Project History Equipment Contact Info
Company Overview
Company History
Mission Statement
8(a) Small Business
Company History:
The Igiugig Village Council formed Iliamna Lake Contractors in July 1998. Faced
with accruing regional economics disaster in the fishing industry, it became the
primary goal of the Village Council to create more economic opportunities for the
local residents. Fishing season lasts one month with unpredictable income, while
construction season lasts from May to October. The Council believed it could train
and use local talent and a limited amount of equipment to obtain jobs in the Lake
Iliamna Region. Additionally, it contracted with tribal programs to create training for
the local residents, acquiring more equipment of its own, and begun to bid for
larger projects.
Since inception ILC has completed several large projects, most recent being the
Phase 1 of the Big Mountain Clean Sweep (2.8m) and the Igiugig Road Project
(4.4m). ILC will continue to work for the Air Force during the 2004 construction
season with the Phase 2 demolition activities scheduled at Big Mountain.
ILC has Hub-Zone designation as well as a Disadvantaged Business Enterprise
(DBE) and is recognized as an 8(a) firm. We have set the standard for the annual
election of Board of Directors and retained managerial staff that will insure the
company goals and objectives are attained and contracts are completed efficiently,
safely and with the highest of standards.
Mission Statement:
Iliamna Lake Contractors aims to provide high quality construction services with a
continuing commitment to quality, professionalism, safety, and on time project
completion. We will achieve this by consistently exceeding the expectations of
customers, design professionals, subcontractors, vendors and the community at
large. These services will be delivered by a team oriented, responsive, innovative,
ethical and skilled staff who participate in training and development programs that
enhance personal growth and the ability to serve our clients.
Page 1 of 2Iliamna Lake Contractors
11/10/2008http://www.ilc-ak.com/company_overview.htm
APPENDIX B
COST WORKSHEET
Renewable Energy Fund
RFA AEA 09-004 Application Cost Worksheet revised 9/26/08 Page 1
Application Cost Worksheet
Please note that some fields might not be applicable for all technologies or all project
phases. Level of information detail varies according to phase requirements.
1. Renewable Energy Source
The Applicant should demonstrate that the renewable energy resource is available on a
sustainable basis.
Annual average resource availability. 3.24 kW / square meter mid-stream power density
Unit depends on project type (e.g. windspeed, hydropower output, biomasss fuel)
2. Existing Energy Generation
a) Basic configuration (if system is part of the Railbelt1 grid, leave this section blank)
i. Number of generators/boilers/other 3 Gensets
ii. Rated capacity of generators/boilers/other 235 kW
iii. Generator/boilers/other type Diesel
iv. Age of generators/boilers/other 1990’s to 2004
v. Efficiency of generators/boilers/other 10.7 kWh / Gallon
b) Annual O&M cost (if system is part of the Railbelt grid, leave this section blank)
i. Annual O&M cost for labor n/a
ii. Annual O&M cost for non-labor n/a
c) Annual electricity production and fuel usage (fill in as applicable) (if system is part of the
Railbelt grid, leave this section blank)
i. Electricity [kWh] 230,000 kWh
ii. Fuel usage
Diesel [gal] 21,000 gallons
Other
iii. Peak Load 52 kW
iv. Average Load 25 kW
v. Minimum Load 16 kW
vi. Efficiency 10.7 kWh / Gallon
vii. Future trends 75 kW peak and 250,000 kWh annual production within 5 years
d) Annual heating fuel usage (fill in as applicable)
i. Diesel [gal or MMBtu] n/a
ii. Electricity [kWh] n/a
1 The Railbelt grid connects all customers of Chugach Electric Association, Homer Electric Association, Golden
Valley Electric Association, the City of Seward Electric Department, Matanuska Electric Association and Anchorage
Municipal Light and Power.
Renewable Energy Fund
RFA AEA 09-004 Application Cost Worksheet revised 9/26/08 Page 2
iii. Propane [gal or MMBtu] n/a
iv. Coal [tons or MMBtu] n/a
v. Wood [cords, green tons, dry tons] n/a
vi. Other n/a
3. Proposed System Design
a) Installed capacity 40 kW
b) Annual renewable electricity generation
i. Diesel [gal or MMBtu] -
ii. Electricity [kWh] 160,700 kWh/yr
iii. Propane [gal or MMBtu] -
iv. Coal [tons or MMBtu] -
v. Wood [cords, green tons, dry tons] -
vi. Other -
4. Project Cost
a) Total capital cost of new system $2,396,830
b) Development cost $1,161,213
c) Annual O&M cost of new system To be determined during pilot phase of project
d) Annual fuel cost n/a
5. Project Benefits
a) Amount of fuel displaced for
i. Electricity 15,000 gallons
ii. Heat -
iii. Transportation -
b) Price of displaced fuel $5.67/gal
c) Other economic benefits To be determined
d) Amount of Alaska public benefits Test bed facility for rural Alaska
6. Power Purchase/Sales Price
a) Price for power purchase/sale To be determined
Renewable Energy Fund
RFA AEA 09-004 Application Cost Worksheet revised 9/26/08 Page 3
7. Project Analysis
a) Basic Economic Analysis
Project benefit/cost ratio To be determined
Payback To be determined
APPENDIX C
GRANT BUDGET
Alaska Energy Authority ‐ Renewable Energy FundBUDGET INFORMATIONBUDGET SUMMARY:Milestone or Task Federal Funds State FundsLocal Match Funds (Cash)Local Match Funds (In‐Kind)Other FundsTOTALS1 ) Phase 1 Reconnaissance$0 $9,200 $9,2002) Phase 2 Feasibility Analysis, Resource Assesmant & Conceptual Design $707,375 $10,800 $718,1753) Phase 3 Final Design & Permitting $428,038 $15,000 $443,0384) Phase 4 Construction, Commissioning, Operation & Reporting $1,211,418 $15,000 $1,226,418$0 $2,346,831 $50,000 $0 $0 $2,396,831Milestone # or Task #BUDGET CATAGORIES:1234TOTALSDirect Labor and Benefits$71,020 $71,020Travel, Meals, or Per Diem$0Equipment$0Supplies$0Contractual Services $9,200 $624,500 $267,250 $356,250 $1,257,200Construction Services$118,000 $639,180 $757,180Other Direct Costs$93,675 $57,788 $159,968 $311,431TOTAL DIRECT CHARGES $9,200 $718,175 $443,038 $1,226,418 $2,396,831RFA AEA09-004 Budget Form
ALASKA ENERGY ENGINEERINGIGIUGIG RISEC COST ESTIMATENOVEMBER 10, 2008ITEM QUAN UNIT UNIT MATLUNIT LAB LAB LABORCONTRFREIGHT TOTALCOST COST HRS HRS RATE COST COST COST COSTPHASE I. RECONNAISSANCESee EPRI Report completed August 31, 20081 lump $0 $0 0 0 $0 $0 $9,200 $9,200PHASE II. FEASIBILITY ANALYSIS, RESOURCE ASSESSMENT & CONCEPTUAL DESIGNTask II.1 - Existing Energy System Assessment See Igiugig Final RPSU CDR completed 11/1/08 1 lump $0 $0 0 0 $0 $0 $35,000 $35,000Task II.2 - Energy Resource Assessmenta. Spring 2009 ADCP and bathymetric survey of project site & prelim Geotech 1 lump $0 $0 40 40 $125 $5,000 $62,000 $67,000b. Summer & Fall 2009 ADCP current vector transect 1 lump $0 $0 40 40 $125 $5,000 $20,000 $25,000c. Analysis of ADCP/ bathymetric data and development of performance specifications for RISEC pilot devices with technical support from EPRI 1 lump $0 $0 20 20 $125 $2,500 $6,500 $9,000Task II.3 - RISEC Pilot Device Design/Solicitationa. Develop RFP for RISEC pilot devices to equipment manufacturers based on site specific performance specifications, 10kW max output each device, to include manufacturer-provided structural support elements (pontoons) 1 lump $0 $0 40 40 $125 $5,000 $2,500 $7,500b. preliminary selection of one horizontal axis and one vertical axis RISEC power unit for pilot project 1 lump $0 $0 20 20 $125 $2,500 $2,000 $4,500Task II.4 - RISEC Pilot Project Permitting and Fish Impact Study Designa. Submit application for FERC General Permit for RISEC Pilot Project 1 lump $0 $0 60 60 $125 $7,500 $5,000 $12,500B-1
ALASKA ENERGY ENGINEERINGIGIUGIG RISEC COST ESTIMATENOVEMBER 10, 2008ITEM QUAN UNIT UNIT MATLUNIT LAB LAB LABORCONTRFREIGHT TOTALCOST COST HRS HRS RATE COST COST COST COSTb. Work with Bristol Bay Science and Research Institute (BBSRI) to develop fish impact study plan based on selected RISEC pilot device configurations 1 lump $0 $0 40 40 $125 $5,000 $10,000 $15,000c. Submit State of Alaska Coastal Management Questionairre for Review 1 lump $0 $0 80 80 $125 $10,000 $10,000Task II.5 - Procure and Deploy RISEC Pilot Devicesa. After pilot project permitting approval procure two selected RISEC pilot devices, FOB Homer, AK2 lump $75,000 $150,000 40 80 $125 $10,000 $5,000 $165,000b. Specify/procure/install remote control wireless RISEC performance monitoring/SCADA equipment, current measurement devices and load banks for mounting on RISEC pilot devices, FOB Homer, AK2 lump $7,500 $15,000 20 40 $125 $5,000 $2,000 $22,000c. Specify & procure materials for RISEC pilot device anchoring systems, FOB Homer, AK 2 lump $2,500 $5,000 20 40 $125 $5,000 $10,000d. Barge/truck/flexi-float RISEC pilot devices and materials from Homer to Igiugig1 lump $0 $0 10 10 $125 $1,250 $7,500 $8,750e. Assemble RISEC pilot devices2 lump $0 $0 20 40 $125 $5,000 $2,000 $7,000f. Fabricate and deploy RISEC pilot device anchoring systems utilizing local equipment and flexi-float barge2 lump $0 $0 15 30 $125 $3,750 $6,000 $9,750B-2
ALASKA ENERGY ENGINEERINGIGIUGIG RISEC COST ESTIMATENOVEMBER 10, 2008ITEM QUAN UNIT UNIT MATLUNIT LAB LAB LABORCONTRFREIGHT TOTALCOST COST HRS HRS RATE COST COST COST COSTg. Deploy RISEC pilot devices using local equipment and boats2 lump $0 $0 15 30 $125 $3,750 $5,000 $8,750h. Commission RISEC pilot devices and remote control wireless performance monitoring/SCADA equipment 2 lump $0 $0 20 40 $125 $5,000 $2,500 $7,500Task II.6 - Smolt and Adult Fish Impact Studies by BBRSIa. Single season, May 15 to July 15 - perform smolt impact study using side-looking sonar, bottom sonar arrays and net sampling1 lump $0 $0 20 20 $125 $2,500 $45,000 $47,500b. Single season, June 15 to Aug 15 - perform adult fish impact study using side-looking DIDSON sonar, observation from shore tower and underwater videography1 lump $0 $0 20 20 $125 $2,500 $25,000 $27,500c. Compile field data and issue fish impact study report for both studied RISEC pilot devices1 lump $0 $0 0 40 $125 $5,000 $15,000 $20,000Task II.7 - Conduct RISEC Pilot Project Remote Performance Monitoringa. Collect and monitor RISEC pilot device performance and river current data daily for one entire seasonal deployment 1 lump $0 $0 10 10 $125 $1,250 $5,000 $6,250b. Perform periodic on-site inspections and maintenance of RISEC pilot devices1 lump $0 $0 40 40 $125 $5,000 $2,500 $7,500b. Remove RISEC pilot devices from river after lake ice begins to form 2 lump $0 $0 20 40 $125 $5,000 $2,000 $7,000B-3
ALASKA ENERGY ENGINEERINGIGIUGIG RISEC COST ESTIMATENOVEMBER 10, 2008ITEM QUAN UNIT UNIT MATLUNIT LAB LAB LABORCONTRFREIGHT TOTALCOST COST HRS HRS RATE COST COST COST COSTc. compile RISEC pilot device performance data and issue performance report1 lump $0 $0 40 40 $125 $5,000 $2,000 $7,000d. Independent performance verification of pilot plant by EPRI1 lump $0 $0 0 0 $125 $0 $25,000 $25,000Task II.8 - Preliminary Analysis & Recommendationsa. Igiugig team to perform comprehensive financial, performance and environmental analysis of alternatives1 lump $0 $0 80 80 $125 $10,000 $10,000 $20,000b. Go/no-go decision made for commercial scale RISEC power project in Igiugig1 lump $0 $0 20 20 $125 $2,500 $10,000 $12,500c. If go, finalize performance specifications and structural element conceptual design for commercial scale RISEC project1 lump $0 40 40 $125 $5,000 $2,500 $7,500f. Produce draft business and operational plans1 lump $0 $0 20 20 $125 $2,500 $10,000 $12,500PHASE III. FINAL DESIGN & PERMITTINGTask III.1 - RISEC Commercial Installation Design/Solicitationa. Obtain record drawings of Igiugig RPSU project for coordination with RISEC grid integration design1 lump $0 $0 0 0 $125 $0 $0b. geotechnical investigation for proposed commercial RISEC installation if required 1 lump $0 $0 20 20 $125 $2,500 $236,000 $238,500c. Complete grid integration study & final design1 lump $0 $0 400 400 $125 $50,000 $50,000B-4
ALASKA ENERGY ENGINEERINGIGIUGIG RISEC COST ESTIMATENOVEMBER 10, 2008ITEM QUAN UNIT UNIT MATLUNIT LAB LAB LABORCONTRFREIGHT TOTALCOST COST HRS HRS RATE COST COST COST COSTd. Issue RFP for RISEC commercial installation to equipment manufacturers based on final performance specifications, structural element conceptual design, geotechnical investigation and grid integration design 1 lump $0 $0 80 80 $125 $10,000 $23,500 $33,500e. Select final RISEC power units and structural elements for commercial installation project 1 lump $0 40 40 $125 $5,000 $20,000 $25,000Task III.2 - Permitting & Site Control for RISEC Commercial Installation a. Submit applications to FERC, Alaska Coastal Management, Corps of Engineers, Fire Marshal, etc.. and perform site control as required for RISEC commercial installation final design 1 lump $0 $0 200 200 $125 $25,000 $25,000Task III.3 - Project Cost a. Provide engineers final cost estimate for RISEC commercial installation project 1 lump $0 $0 20 20 $125 $2,500 $2,500 $5,000Task III.4 - Project Benefitsa. Provide cost benefit analysis of proposed project1 lump $0 $0 20 20 $125 $2,500 $2,500 $5,000Task III.5 - Final Analysis & Recommendations for Commercial Installation Project $0a. Finalize business & operational plans 1 lump $0 $0 0 10 $125 $1,250 $2,000 $3,250PHASE IV. CONSTRUCTION, COMMISSIONING, OPERATIONS & REPORTINGTask IV.1 - Construction Scheduling & Procurement a. Provide construction plan and schedule1 lump $0 $0 20 20 $125 $2,500 $2,500B-5
ALASKA ENERGY ENGINEERINGIGIUGIG RISEC COST ESTIMATENOVEMBER 10, 2008ITEM QUAN UNIT UNIT MATLUNIT LAB LAB LABORCONTRFREIGHT TOTALCOST COST HRS HRS RATE COST COST COST COSTb. Procure RISEC power units FOB Homer, AK 1 lump $125,000 $125,000 40 40 $125 $5,000 $5,000 $135,000c. Award contract(s) for on-site construction (or off-site fabrication) of structural elements1 lump $0 $0 40 40 $125 $5,000 $250,000 $255,000b. Procure grid integration equipment, switchgear, overhead (or submarine) cables, and all other required construction materials FOB Homer, AK 1 lump $100,000 $100,000 40 40 $125 $5,000 $105,000f. Update predicted material costs during procurement, track construction costs and update budget throughout construction 1 lump $0 $0 40 40 $125 $5,000 $5,000Task IV.2 - Construction Mobilization a. Barge/truck/flexi-float RISEC devices and all construction materials from Homer to Igiugig1 lump $0 $0 20 20 $125 $2,500 $0 $2,500b. Tool spread & crew mobilization/ demobilization2 lump $2,500 $5,000 20 40 $125 $5,000 $5,000 $15,000Task IV.3 - RISEC Installation & Commissioninga. Field-assemble and deploy RISEC devices and install grid integration equipment/cable interties 1 lump $0 $0 60 60 $125 $7,500 $100,000 $107,500b. Commission RISEC installation and remote monitoring/ SCADA system1 lump $0 $0 80 80 $125 $10,000 $20,000 $30,000c. Independent performance verification of commercial plant by EPRI1 lump $0 $0 10 10 $125 $1,250 $30,000 $31,250B-6
ALASKA ENERGY ENGINEERINGIGIUGIG RISEC COST ESTIMATENOVEMBER 10, 2008ITEM QUAN UNIT UNIT MATLUNIT LAB LAB LABORCONTRFREIGHT TOTALCOST COST HRS HRS RATE COST COST COST COSTTask IV.4 - Environmental Monitoring of Final RISEC Installationa. Perform single season smolt and adult fish impact study using side-looking sonar, bottom sonar arrays, net sampling and tower observations to confirm predicted impact of final RISEC installation1 lump $0 $0 20 20 $125 $2,500 $75,000 $77,500b. Issue final environmental reports as required by permitting agencies1 lump $0 $0 60 60 $125 $7,500 $5,000 $12,500Task IV.5 - Analysis & Recommendationsa. Update business plans and power rate based on final construction costs1 lump $0 $0 20 20 $125 $2,500 $2,000 $4,500b. Produce final report with analysis and recommendations, as-built drawings1 lump $0 $0 40 40 $125 $5,000 $10,000 $15,000c. Monitor operations and maintenance cost and energy production, produce periodic reports, recommendations, with long term support 2013-2017 by EPRI1 lump $0 $0 240 240 $125 $30,000 $120,000 $150,000Task IV Overhead$0 $53,200 $53,200Audit Grants 1 lump $6,000 $6,000Rent Heavy Equip. 1 lump $20,000 $20,000Commission/Train Operators 1 lump 80 80 $80 $6,400 $6,400Superintendent Overhd Off-Site40 hr1 40 $80 $3,200 $3,200Superintendent Overhd On-Site40 hr1 40 $80 $3,200 $3,200Crew Travel Time 60 hr1 60 $80 $4,800 $4,800Crew Airfares 6 trips $1,800 $1,800Crew Per Diem 150 mn.dy$6,300 $6,300Housing Rent2mo.$1,500$1,500B-7
ALASKA ENERGY ENGINEERINGIGIUGIG RISEC COST ESTIMATENOVEMBER 10, 2008ITEM QUAN UNIT UNIT MATLUNIT LAB LAB LABORCONTRFREIGHT TOTALCOST COST HRS HRS RATE COST COST COST COSTTask IV FreightFreight Homer - Igiugig 1 lump $50,000 $50,000Project De-Mob 1 lump $10,000 $10,000Misc Small Freight & Gold Streaks 1 lump$5,000$5,000Project SUB-TOTAL $400,000 2,800$322,500$1,362,900$0$2,085,400Engineering (Design & CCA)1 lump $0Construction Management1 lump$0PROJECT SUB-TOTAL $400,000$322,500$1,362,900$0$2,085,400Contingency15 %$312,810TOTAL PROJECT COST$2,398,210B-8
APPENDIX D
ELECTRONIC COPY OF APPLICATION
(REFER TO ENCLOSED DISC)
APPENDIX E
RESOLUTION & SUPPORTING LETTERS
Lake and Peninsula Borough
Po. Box 495
King Salmon, Alaska 99613
Telephone: (907) 246-3421
Fax: (907) 246-6602
Renewable Energy Grant Fund
Alaska Energy Authority
813 West Northern Lights Blvd.
Anchorage, AK 99503
Subject: Village of Igiugig River In-Stream Energy Conversion (RISEC) Project
Renewable Energy Fund Grant Application -Letter of Support
Application Review Committee:
This letter is provided in support of the Village of Igiugig's Renewable Energy Fund
grant application. As you are aware, the high cost of fuel has created significant
economic hardship in rural Alaska communities. Due to the difficult logistics and
increased cost of barging fuel up the Kvichak River, the Village of Igiugig and other
Iliamna Lake villages suffer an even higher cost of fuel than many other coastal
communities in this region.
The salmon fishery is the most important commercial and subsistence resource in the
Bristol Bay region. The thorough environmental testing included in the pilot portion of
this project will document and mitigate any potential or unexpected adverse impacts on
adult and juvenile salmon. This will insure that any future commercial RISEC installation
will be done in an environmentally friendly manner and will have no negative impacts on
the salmon resource.
The proposed Kvichak River RISEC project has the potential to greatly reduce Igiuigig's
reliance on expensive imported diesel fuel for power generation and to lower the future
cost of electricity for the entire community. If successful, this project could also provide
a blueprint for other similarly situated communities to adopt RISEC technology, thereby
benefiting the entire Lake and Peninsula Bourough as well as other regions of the state.
Therefore the Lake and Peninsula Borough fully supports the efforts of the Village of
Igiugig to test and apply this technology through REF Grant Funds and requests that the
Review Committee carefully review the merits of this application.
Chignik Bay' Chignik Lagoon' Chignik Lake' Egegik' Igiugig' Iliamna· Ivano! Bay· Kokhanok· Levelock
Newhalen • Nondalton' Pedro Bay' Perryville' Pilot Point· Pope Vannoy' Port Alsworth' Port Heiden' Ugashik
If you have any questions please call me at (907) 246-3421, or fax your comments to
(907) 246-6602.
Sincerely,
Lake and Peninsula Borough
({]; /7/~/
I)~!/!Y~
i
Lamar Cotten
Borough Manager
cc: Dallia Andrew, President, Igiugig Village Council
APPENDIX F
TECHNICAL DATA
System Level Design, Performance, Cost and Economic
Assessment – Alaska River In-Stream Power Plants
Yukon at Eagle
Tanana at Whitestone
Kvichak at Igiugig
Project: Alaska River In-Stream Energy Feasibility Study
Report: EPRI RP 006 Alaska
Author: Mirko Previsic
Contributors: Roger Bedard, Brian Polagye
Date: October 31, 2008
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
DISCLAIMER OF WARRANTIES AND LIMITATION OF LIABILITIES
This document was prepared by the organizations named below as an account of work
sponsored or cosponsored by the Electric Power Research Institute Inc. (EPRI). Neither
EPRI, any member of EPRI, any cosponsor, the organization (s) below, nor any person
acting on behalf of any of them.
(A) Makes any warranty or representation whatsoever, express or implied, (I) with
respect to the use of any information, apparatus, method, process or similar item
disclosed in this document, including merchantability and fitness for a particular
purpose, or (II) that such use does not infringe on or interfere with privately owned
rights, including any party’s intellectual property, or (III) that this document is suitable
to any particular user’s circumstance; or
(B) Assumes responsibility for any damages or other liability whatsoever (including any
consequential damages, even if EPRI or any EPRI representative has been advised of the
possibility of such damages) resulting for your selection or use of this document or any
other information, apparatus, method, process or similar item disclosed in this document.
Organization(s) that prepared this document
re vision consulting, LLC
Electric Power Research Institute
2
Table of Contents
1. Introduction and Summary ..........................................................................................6
2. Site Selection ...............................................................................................................9
2.1. Electrical Interconnection .......................................................................................11
2.2. Load Matching and Energy Storage .......................................................................13
3. RISEC Design ............................................................................................................15
3.1. Support Structure for Natural Rivers ......................................................................15
3.2. Complete Device Submersion.................................................................................18
3.3. Device Performance Calculations ...........................................................................21
3.4. Rotor Performance ..................................................................................................21
3.5. Powertrain ...............................................................................................................23
3.6. Investigation of Design Alternatives ......................................................................27
3.7. Integrated Modeling................................................................................................29
3.8. Uncertainties in cost predictions .............................................................................29
4. Site Design .................................................................................................................32
4.1. Turbine arrangement ...............................................................................................32
5. Results for Igiugig on the Kvichak River ..................................................................33
5.1. Pilot Plant Cost .......................................................................................................38
5.2. Commercial Plant Performance and Cost ...............................................................39
5.3. Feedback Effects on Flow.......................................................................................44
5.4. Economic Analysis .................................................................................................46
6. Results for Eagle on the Yukon River .......................................................................49
6.1. Pilot Plant Cost .......................................................................................................55
6.2. Commercial Plant Performance and Cost ...............................................................56
6.3. Feedback Effects on Flow.......................................................................................59
6.4. Economic Analysis .................................................................................................61
7. Results for Whitestone on the Tanana River ......................................................63
7.1. Pilot Plant Cost .......................................................................................................67
7.2. Commercial Plant Performance and Cost ...............................................................68
7.3. Feedback Effects on Flow.......................................................................................73
7.4. Economic Analysis .................................................................................................77
8. Conclusions ................................................................................................................80
9. References ...............................................................................................................85
10. Appendix A - River Extraction Model ......................................................................86
11. Appendix B – RISEC Technologies under Development..........................................90
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Table of Figures
Figure 2: Cross sectional profiles of three sites during annual average river discharge rates 10
Figure 3: Average monthly river velocities at the three sites 10
Figure 4: Average monthly power densities at the sites of interest 11
Figure 5: Generic electrical interconnection diagram 12
Figure 6: Iguigig Generator Load Data 14
Figure 7: Pontoon Structure with lowered rotors 16
Figure 8: Pontoon structure with raised rotors. Human figure on pontoon is 6ft tall. 17
Figure 9: Pontoon Structure (front view) 17
Figure 10: Pontoon structure mooring arrangement 18
Figure 11: Completely submersible pontoon structure 19
Figure 12: Floating Device before deployment 20
Figure 13: Device during submersion process 20
Figure 14: Device during controlled ballasting 20
Figure 15: Device completely submersed 21
Figure 16 - Power Coefficient as a function of Tip-Speed Ratio (CP) 22
Figure 17: Drive-train schematic 24
Figure 18: Power-train module at 3 different diameters 25
Figure 19: Power-train Design 25
Figure 20: Protective screen 26
Figure 21: Example of fish screen 27
Figure 22: Cost projection as a function of Development Status 30
Figure 23: Community Profile Map and Water velocity readings at proposed site: June 20th 2007
34
Figure 24: River cross-sectional profile at annual average discharge rate 35
Figure 25: Depth-Averaged Velocity Distribution across river at annual average discharge rate 36
Figure 26: Monthly Average Power Output of 40kW rated RISEC farm (load limiting month is
August) 37
Figure 27: Monthly Average Electrical Power Output for 9-unit RISEC plant rated at 40kW. 38
Figure 28 – Iguigig at Kvichak: velocity profile, 12 rotors – 23 kW extraction 45
Figure 29 – Iguigig at Kvichak: depth profile, 12 rotors – 23 kW extraction 45
Figure 30: Cumulative cost vs. cumulative revenue 47
Figure 31: Cumulative cost vs. cumulative revenue 48
Figure 32: View onto village and Deer Island 50
Figure 33: Cross sectional profile at USGS calibration site at annual average discharge rate 51
Figure 34: Cross sectional variation in depth-averaged velocity at USGS calibration site at
annual average discharge rate 52
Figure 35: Likely site location (shown in red) 52
Figure 36: Monthly average power production 54
Figure 37 – Eagle at Yukon: depth profile, 8 rotors –17 kW extraction 60
Figure 38 – Eagle at Yukon: velocity profile, 8 rotors –17 kW extraction 60
Figure 39: Cumulative cost vs. cumulative revenue 62
Figure 40: Whitestone Community on the Tanana River 63
Figure 41: Site Overview 63
Figure 42: River cross-sectional profile at Whitestone at annual average discharge rate 65
4
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Figure 43: Depth-averaged cross-sectional velocity distribution at site near Whitestone at annual
average discharge rate 66
Figure 44: Monthly average electrical power production from commercial RISEC plant near
Whitestone 67
Figure 45 – Whitestone at Tanana: depth profile, 120 rotors –123 kW extraction 74
Figure 46 – Whitestone at Tanana: velocity profile, 120 rotors –123 kW extraction 74
Figure 47 – Channel velocity reduction (cross-sectional average) as a function of extraction 75
Figure 48 – Channel power density reduction (cross-sectional average) as a function of
extraction 75
Figure 49 – Power output per rotor as a function of extraction 76
Figure 50: Cumulative cost vs. cumulative revenue 78
Figure 51: Cumulative cost vs. cumulative revenue 79
List of Tables
Table 1: Pontoon Specification 18
Table 2: Powertrain housing specifications 26
Table 3 - EPRI cost estimate rating table 31
Table 4: Technical Parameters 36
Table 5: Monthly Frequency Distributions at the deployment site 37
Table 6: Pilot Plant cost and performance (2007 $) 39
Table 7: Cost and performance of a 3-unit array at Igiugig site (cost in 2007 dollars) 42
Table 8: Iguigig plant configured to provide a constant output over the whole year (base-load) 43
Table 9: Turbine Parameters 44
Table 10: Site Parameters 44
Table 11: SPP calculation for baseline scenario 46
Table 12: Baseload Scenario for Iguigig Village 47
Table 13: Technical Parameters 53
Table 14: Monthly frequency distributions for cross-section average velocities at the site 54
Table 15: Cost and Performance of Pilot Unit at Eagle (2007 $) 55
Table 16: Cost and performance of a single at Eagle site (cost in 2007 dollars) 58
Table 17: Turbine Parameters 59
Table 18: Site Parameters 59
Table 19: SPP Calculation for Eagle site 61
Table 20: Whitestone Community Monthly Load Patterns 64
Table 21: Technical Parameters 64
Table 22: Monthly frequency distribution of velocities at site near Whitestone 66
Table 23: Pilot Plant Performance and Cost at Whitestone (2007 $) 68
Table 24: Cost and performance of a 30-unit array at Whitestone site (cost in 2007 dollars) 71
Table 25: Isolated grid scenario for Whitestone village 72
Table 26: Turbine Parameters 73
Table 27: Site Parameters 73
Table 28: SPP Calculation for Whitestone 77
Table 29: SPP Calculation for Whitestone Baseload Scenario 78
Table 30: Site Summary 81
5
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
1. Introduction and Summary
The Electric Power Research Institute (EPRI), under the sponsorship of the Alaska Energy
Authority (AEA), Anchorage Municipal and Light, Chugach Electric and the Village of Iguigig,
conducted a study to investigate the feasibility of a technology known as River In-Stream Energy
Conversion (RISEC) for Alaska river applications. RISEC technology converts the kinetic
energy of water in free-flowing rivers into electricity by placing water turbines (similar to wind
turbines) directly into the flowing water.
A total of six (6) river sites were selected for site assessment; the results are contained in
Reference 1. After careful review, three sites were selected for conceptual level feasibility
studies, the results of which are described in this report. The three sites were:
• Tanana River at Whitestone
• Yukon River at Eagle
• Kvichak River at Igiugig
This report describes the results of a system-level design, performance, cost and economic study
of RISEC power plant installed at the three Alaska river sites of interest. Eagle and Igiugig are
villages with isolated grid infrastructures, while Whitestone, near Big Delta, is located near a
26kV transmission line that would allow for a potentially larger-scale build-out.
Currently, RISEC devices are at a very early stage of development. In order to carry out
performance, cost and economic assessments, EPRI established a baseline device design
consisting of open rotor horizontal axis turbines mounted on a pontoon structure. Based on that
baseline design, a parametric performance, cost and economic model was established to adapt
the technology to the site conditions encountered at various sites of interest.
Cost estimates were cross-checked with data supplied by Verdant Power from their 5m diameter
rotor design. While this proved a useful point of comparison, it is important to understand that
Verdant Power’s machine is significantly larger in scale then the conceptual designs outlined in
6
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
this report. As such, data could not directly be applied to this application, but was useful as a
validation point for some of the model’s underlying assumptions.
The economic model used the simple payback period (SPP) as an indicator of the economic
value of the potential project. SPP refers to the period of time required for the return on an
investment to "repay" the sum of the original investment. For example, a $1000 investment
which returned $500 per year would have a two-year payback period. It intuitively measures
how long something takes to "pay for itself"; shorter payback periods are obviously preferable to
longer payback periods (all else being equal). Payback period is widely used due to its ease of
use.
The SPP for a RISEC power plant is the number of years it takes for the accumulated value of
the revenues from the sale of electricity to equal the capital cost and the yearly operating and
maintenance cost of the plant.
Iguigig and Eagle were treated as remote villages, and the RISEC plants were sized to meet a
significant portion of the daily load (40kW for Iguigig and 70kW for Eagle). Whitestone was
treated as a grid connected with a 26kV line that could likely be used to export more then 5MW.
However, to be conservative, this study used a plant rated at 500kW. Any excess electricity
produced is assumed to be absorbed by electrical resistive loads such as heating.
The value of electricity revenues is the avoided cost. For a rural Alaskan utility running on
diesel, the avoided cost is essentially the fuel cost. With fuel costs of $8/gallon delivered and
efficiencies of 13kWh/gallon, the avoided cost is typically 65 cents/kWh. The O&M cost of a
diesel genset is 2-5 cents/kwh, but it was conservatively assumed that there would be no O&M
savings.
The following assumptions about escalation of costs were made:
Escalation of non fuel cost = 3% per year
Escalation of fuel costs = 8% per year
7
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
The results of this study showed that:
As EPRI has found in previous ocean wave and tidal feasibility studies, economic
viability of the deployment site is directly linked to the power density at the site.
Rotor size for a horizontal axis turbine is limited by the water depth at the deployment
sites. This limits the technology’s ability to scale a single horizontal axis rotor to higher
power outputs.
Power density peaks in Alaskan rivers occur during summer periods. This mismatch
between resource availability and demand limits grid penetration. However some of this
could be shifted by using electricity for alternative purposes such as heating.
The commercial scale economics is limited in the isolated villages. Small deployment
scales will yield higher comparable cost. This is not only true for RISEC technology, but
is true for many other generation technologies as well.
Small changes in the local velocities will create significant changes in power density
since power density is a function of the velocity cubed. Detailed assessment of the local
flow variations becomes a very important aspect of siting a RISEC device.
Operational issues with this technology remains to be addressed with in-river tests. In
particular, interference with ice, debris and wildlife need to be studied and, where
required, mitigation measures incorporated into the RISEC device design.
The SPP for remote village isolated-grid Iguigig is 3 to 4 years, for remote village
isolated-grid Eagle 4 to 5 years, and for the remote village but grid-connected
Whitestone case 8 to 9 years.
RISEC is an evolving technology field with different manufacturers pursuing different device
concepts. Appendix B contains a list of developers active worldwide. It is included to provide
the reader with an understanding of the range of technologies under development.
8
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
2. Site Selection
Site Overviews
In the spring of 2008, EPRI completed a site characterization study, in which a total of six sites
in Alaska were assessed {Reference 1}. After reviewing the data for those six sites, three sites
were selected for conceptual feasibility design studies. The three selected sites are: (1) Tanana
River at Whitestone, (2) Yukon River at Eagle and (3) the Kvichack River at Igiugig. The
following illustration shows the location of the selected three sites in yellow. The Igiugig and
Eagle sites are connected to small isolated village grids, while the Whitestone site is located near
a 26kV transmission line.
Yukon at Pilot Station
Tanana at Manley Hot
Springs
Yukon at Eagle
Tanana at Whitestone
Taku at Juneau
Kvichak at Igiugig
Figure 1: Site Location Overviews
The following sections summarize critical site condition data at the three sites of interest. The
following figure shows the cross-sectional transects at the USGS measurement stations of the
three sites.
9
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
-14.0
-12.0
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
0 50 100 150 200 250 300 350 400 450 500
Distance from Shore (m)Water Depth (m)Iguigig @ 17200 ft^3/s Eagle @ 183000 ft^3/s Whitestone @ 41200 ft^3/s
Figure 2: Cross sectional profiles of three sites during annual average river discharge rates
The following two figures represent the monthly average velocities and the monthly average
cross sectional power densities. The figures show that the Iguigig site has much less
summer/winter variability than the other two sites. This is a direct result of the storage provided
by Lake Iliamna upstream of the Iguigig site. The higher river discharge rates during summer
and associated higher velocities are a direct result of snow melt-off.
0.0
0.5
1.0
1.5
2.0
2.5
0123456789101112
MonthMonthly average velocity (m/s)Yukon @ Eagle Tanana @ Whites tone Kvichak @ Iguigig
Figure 3: Average monthly river velocities at the three sites
10
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
1 23 4 56 78 9101112
MonthMonthly average power density(kW/m^3)Yukon @ Eagle Tanana @ Whites tone Kvichak @ Iguigig
Figure 4: Average monthly power densities at the sites of interest
Alaskan discharge rates are fairly constant over the short term, however inter-annual variability
can be significant. The hydrokinetic power density of a free-flowing stream relates to the cube
of fluid velocity. The figure above shows the seasonal variability of power densities at the site.
It shows that the power densities for all three sites are much higher during summer than winter.
Hydrokinetic power density at a river site relates directly to rotor power output and forms
therefore a critical part of the technology’s economics.
All three sites are located near small Alaskan villages. Grid interconnection could be
accomplished using a short underwater umbilical cable to shore from the unit deployment
location. Because micro-siting studies have not been completed, it was assumed that all three
deployment locations will require about 75m of underwater electrical cabling back to shore from
their deployment locations and are interconnected on shore by a distribution line.
2.1. Electrical Interconnection
All deployment sites are within a few hundred yards of a suitable distribution line that could be
used to connect the generation scheme. In a very generic sense, facilities with a total nameplate
capacity of less then 1MW will require the following: a dedicated transformer, revenue metering,
a disconnect device, a circuit interrupting device and a multifunction relay. In addition a RISEC
deployment in rural Alaska will likely require real time satellite-based SCADA monitoring that
11
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
includes voltage/frequency/power output, fault alarms, and webcams. It is expected that most
deployments in Alaska will be less then 1MW in capacity. All devices are connected to the same
cable that connects the array back on land. The following illustration shows the general
arrangement of these devices in clusters.
Figure 5: Generic electrical interconnection diagram
One of the key engineering issues to be addressed is connecting the RISEC devices, located in
the river with the electrical grid on-shore. While the overland transmission is relatively simple
and can be done by extending the existing grid network to the deployment site, the difficulty is
with extending that transmission into the river. There are two different options that could be
considered: 1) directional drilling and 2) ballasting the cable to the river-bed. These options are
briefly discussed below.
Directional drilling is by far the most reliable option. Using this technique, a conduit will be
buried sufficiently deep to fully protect the cable even during ice-breakup. Directional drilling is
a well-established method, but will also be relatively expensive. Initial budgetary estimates by
an Alaskan contractor came in between $150 to $300 per foot of directional drilling for a 4-inch
diameter steel conduit. For more remote areas that do not have road access, cost will likely
increase for mobilization charges because the equipment would need to be flown in.
A secondary option is simply to put the cable into a trench down to the water and then lay the
cable onto the river-bed by ballasting the cables. The key issue with this option is the cable
exposure during spring breakup, where ice-blocks scour the river-bed. As such, the cable would
need to be removed while the units are retrieved during spring breakup. The cable could be
12
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
ballasted using concrete blocks or concrete mats during deployment, which will likely require
diver support. In order to achieve lower cost deployments, diver intervention needs to be
avoided where possible. This would call for a cable design that integrates ballasting options
such as clump-weights or interlocking steel pipe pieces that could be clamped to the cable at
regular spacing to provide sufficient ballast and keep the cable in place. Ideally, such a cable
could be deployed and recovered from a small working boat. It would require the cable to be
sufficiently reinforced and flexible to handle the additional stress-levels and fatigue from the
annually reoccurring deployment and recovery procedures. For the purpose of this conceptual
design study, it was assumed that such a cable and deployment/recovery procedure can be
designed and a fixed cost of $40,000 included in the cost buildup. The high cost of directional
drilling would likely render this technique uneconomic for most of the smaller-scale
deployments.
For places where ice-breakup and seabed scouring is not an issue, the cable could be placed in a
3” schedule 40 or schedule 80 pipe and laid on the river bed. The weight and structural integrity
of this type of pipe would provide the cable with additional armor and keep it in place by its own
weight. This type of piping is transported to the site in 20’ or 40’ length and welded together
onsite.
2.2. Load Matching and Energy Storage
Electricity is an energy source that does not allow for easy energy storage. Demand and supply
need to be closely matched to ensure voltage stability in the grid network. In remote grids, this
is typically accomplished by running the generator in a load-following mode, meaning that the
diesel generator automatically adjusts it’s power output automatically as the electrical load on
the network changes. In order to maximize the economic benefits of a RISEC plant, one needs
to be able to always sell the electricity into the grid. Because RISEC plant power output is
expected to be highest during summer months when loads on the grid network is lowest there is a
need to limit the rated plant capacity to the summer low in electricity loads. Further, loads vary
throughout the day. Typically more electricity is used during daytime then during nighttime. In
order to accommodate these short-term fluctuations, some energy storage may be required and/or
excess energy could be dissipated for heating purposes, displacing further heating fuel. Because
13
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
little data was available on hourly load fluctuations, this study does not account for energy
storage requirement. AEA has measured hourly data in Iguigig and also have typical daily and
seasonal load variation models that can be used to create hourly data from monthly or annual
data. These grid integration issue would need to be studied further as this technology is
implemented in remote villages. The following shows some load data for Iguigig as an example
of the potential short-term load variability.
Figure 6: Iguigig Generator Load Data
14
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
3. RISEC Design
The purpose of this design study was to establish a conceptual RISEC device suitable for
deployment at the selected sites. A horizontal axis machine was chosen because it allowed for
the reuse of empirical data for rotor performance from the wind industry, and because Verdant
Power, which cooperated in this study, provided access to performance and cost data for their
5m-diameter horizontal axis machine. Turbine diameter is limited in all locations by the water
depth. The resulting small turbine diameters for this application did not lend themselves well to
a variable pitch rotor. A fixed pitch rotor was chosen because of the resulting lower machine
complexity. Vertical axis machines were not evaluated as part of this study, but cost and site-
design issues are not likely to be very different from a horizontal axis machine.
A RISEC machine consists of multiple horizontal axis rotors that are immersed into the stream,
connected to a power conversion system that generates electricity suitable for direct connection
to the electrical grid. These power-modules are mounted onto a structure suitable for the
installation location. During the study, different design options were investigated and
parametrically modeled to determine and quantify principal advantages and disadvantages.
Mounting multiple rotors on a single support structure was a primary strategy to reduce cost and
improve the economic attractiveness of such a design. The following sections provide an
overview of the various elements investigated.
3.1. Support Structure for Natural Rivers
For deployment in natural rivers, a floating platform was designed, consisting of two floating
pontoons from which rotors are suspended into the water column. The following illustrations
show the pontoon-boat with four rotors with a diameter of 1 meter suspended below the
structure. Pontoon boats have been extensively used as leisure crafts and can be manufactured
using existing capabilities at relatively low cost. The structure is designed to be constructed
from marine grade aluminum and can be shipped in standard containers to the site, where the
units are bolted together and deployed. The structure is scaleable and could accommodate more
rotors or larger rotors, depending on how wide the structure is built. A water-tight box on the
deck accommodates frequency converters and other electrical protection equipment required for
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grid interconnection. The mooring system consists of a combination of conventional steel cables
and chains. An embedment anchor provides the necessary holding strength. The following
illustrations show 3-D renderings of the device. In order to provide directional stability, the
rotors are counter-rotating (the two inner rotors rotate in the opposite direction of the two outer
rotors) to offset their torque, and the rotors are mounted toward the back of the pontoon. The
rotor size can be adjusted to accommodate the water depth at the site. If rotor size is increased,
the corresponding pontoon width will be increased as well. The basic structure can
accommodate rotor sizes from 1m to 4m in diameter.
Figure 7: Pontoon Structure with lowered rotors
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Figure 8: Pontoon structure with raised rotors. Human figure on pontoon is 6ft tall.
Figure 9: Pontoon Structure (front view)
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Figure 10: Pontoon structure mooring arrangement
To access the individual rotors for maintenance such as cleaning of the screen, they can be raised
onto the deck. The rotors are connected by a strut to pin-type bearing that allows the rotors
mounted at the end of the strut be rotated out of the water. In order for this to be accomplished
without the rotors interfering with one another, they are offset in longitudinal directions, creating
two bays through which they can be raised and lowered. A simple lever allows this operation to
be completed easily for smaller rotors. If the same mechanism is applied for larger rotors, a
winch could be used to raise and lower the individual rotors.
The following provides a summary of the specifications for this pontoon-structure. It is
important to realize that depending on the rotor size, the width and the weight of the structure
will change. The initial base-design and the above illustrations are based on a rotor diameter of
1m. The pontoon will, however, provide sufficient stability and buoyancy for rotors up to 4m in
diameter.
Table 1: Pontoon Specification
Pontoon Length 10m
Pontoon Diameter 0.6m
Pontoon Width 4m – 16m
Rotor Diameter 1-4m
Number of rotors 4
Total Rotor Swept Area 3.1m2 – 50m2
Material Marine grade aluminum
Total Assembly Weight 1800kg (depends on rotor size)
3.2. Complete Device Submersion
In order to be able to operate below the ice in winter, a completely submersible design
alternative was evaluated. Complete submersion of the device will also allow the device to
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avoid most of the debris, present near the water surface. The device consists of a very similar
pontoon structure that can be ballasted with water in order to completely submerse. As shown in
the figure below, the pontoon structure is very similar, with the only differences being that 1) the
rotors are fixed above the bottom two pontoons, 2) a third pontoon was added to provide stability
during submersion, and 3) a hose assembly (shown in red) allows for ballasting and de-ballasting
of the structure by allowing the adding and removal of water from the pontoons.
Figure 11: Completely submersible pontoon structure
The following figures illustrate the ballasting/de-ballasting process of the structure. First, the
device is towed out to the deployment site and connected to its front-end mooring using an
embedment anchor or other means to secure it to the riverbed. Once the device is in place, the
boat is attached to the back and the device’s hose assembly is placed on deck. The hose
assembly enables the adding of water selectively to the three pontoons to allow for controlled
submersion of the device.
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Figure 12: Floating Device before deployment
Next the bottom pontoons are selectively ballasted, leading to slow submersion of the device.
The top-tank still provides buoyancy, ensuring that the device remains upright during
submersion.
Figure 13: Device during submersion process
Figure 14: Device during controlled ballasting
Once the device sits on the river-bed, the top-side pontoon is ballasted as well to ensure that the
device sits firmly on the river-bed. The hose assembly is either disconnected or stored
submersed on the device itself.
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Figure 15: Device completely submersed
The recovery process will work in a very similar way. First the hose assembly is recovered to
selectively pump air into the submersed pontoons (starting with the top-pontoon to provide
stability).
3.3. Device Performance Calculations
To calculate turbine performance, two procedures were used: one for variable speed and one for
fixed speed operation. Using the frequency distribution of velocities at the site, the power
density can be calculated using the following equation:
P/A=0.5 x Rho x V3
Where P/A is measured in watts per square meters, where P is the power in watts, A is the swept
area in m2, Rho is the water density (1000kg/m3) and V is the velocity measured in meters per
second. Once the power density is known, it can be multiplied by the rotor swept area to obtain
the total power acting on the rotor disk.
The remaining efficiency factors are applied to get from fluid power to electrical power. For a
rotor operating at variable speed, the rotor’s conversion efficiency is effectively constant.
However, for a rotor operating at fixed speed, the efficiency changes as a function of tip-speed
ratio, meaning at each velocity, the rotor will perform at a different efficiency. In order to
optimize rotor performance, an iterative routine was used to determine optimal rotor speed.
3.4. Rotor Performance
The efficiency of a rotor (operating at a fixed blade pitch angle) in a free-flowing stream can be
expressed as a function of its tip-speed ratio. The tip-speed ratio is the ratio between the velocity
of the rotor’s tip and the free-stream water velocity. If the fluid speed increases, the rotor speed
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has to increase as well to keep the rotor performing optimally. The following illustration shows
a power coefficient for a small fixed pitch wind-turbine rotor. The performance of a water
turbine should be similar.
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
02 46 8
Ti p Spe e d Ra tioPower Coefficient10
Figure 16 - Power Coefficient as a function of Tip-Speed Ratio (CP)
It is important to understand that this tip-speed ratio of the turbine can be influenced by blade
design and number of blades employed. For the purpose of this design, a three-bladed rotor was
chosen with a tip-speed ratio of four and a power coefficient of 40%. While this power
coefficient is significantly below the 59% Betz limit (the theoretical upper limit to conversion
efficiency from open rotor systems), this was viewed as a representative efficiency for smaller
machines. For smaller machines, turbulent losses induced by its blade-tips tend to be higher than
losses for larger diameter rotors, leading to lower overall power conversion efficiencies.
The rotational speed must be adjusted to yield the optimal tip-speed ratio. This adjustment
requires that the generator is able to operate at variable speed. The variable speed operation can
be attained by using a frequency converter, which converts the variable frequency input of the
generator to a fixed synchronized frequency and voltage suitable for interconnection with the
electric grid.
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The tip speed of an underwater turbine is limited by cavitation. Cavitation is caused by water
vaporizing due to pressure reduction on the back of the propeller blades. This distortion of the
flow pattern can significantly reduce power output and erode the rotating propeller blades.
While this critical cavitation speed is a function of many factors, including blade profile, water
depth and turbulence, for the purpose of this study a limit on the rotor’s tip-speed of 8m/s was
assumed to keep the rotor in a safe operating range.
Additional losses occur in the conversion of primary mechanical energy into electricity. The
following list offers typical efficiencies of a wind-turbine power train consisting of a gearbox,
generator, frequency converter and step-up transformer.
Rotor Efficiency 40%
Gearbox 95%
Generator 95%
Frequency Converter 98%
Step-up transformer 98%
Power-train combined efficiency 34%
The resulting overall efficiency (water to wire) at the rotor’s efficiency peak is 34.4% (40%
power coefficient times 86% power train combined efficiency). A more detailed discussion on
performance of horizontal axis rotors can be found in references 8, 9, 10 and 11.
3.5. Powertrain
The power-train of the system is very similar to a wind-turbine and consists of the following
elements as outlined in the figure below:
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Legend
1. Rotor
2. Gearbox
3. PM Generator
4. Frequency Converter
5. Step-up Transformer
6. Electrical Grid
Figure 17: Drive-train schematic
A basic strategy in the development of this conceptual design was the ability to re-use
components from small wind turbines and thereby minimize risky and costly custom
developments. However, there are a few fundamental differences between a wind turbine and a
RISEC device:
1. RISEC rotors turn slower than equivalently rated wind machines because the rotor’s tip-
speed is limited by cavitation.
2. Because of the slower rotation, blade-root stresses are higher at equivalent machine size.
At the same time, the rotor diameter is smaller because of the higher power-density in
water than in air.
3. RISEC devices operate below the water, requiring additional component protection such
as encasing the generator and other components in water-tight enclosures.
4. There is a good chance that debris suspended in mid-water can damage the open rotors.
While there is limited experience with such issues, it is likely that some sort of a screen
will be required to protect the rotating blades from such damage. Such screens will likely
require frequent cleaning. Also, flow interference of the screen on the rotor would need
to be evaluated.
The following paragraphs provide outlines of the device’s key elements, including the water-
tight housing, the rotor and the protective screen. The following is a sketch of the power-train
module in three different sizes. Dimensions shown are in millimeters.
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Figure 18: Power-train module at 3 different diameters
The generator housing provides an air-tight enclosure to protect the electric generator and
gearbox from water intrusion. It also transfers the principal loads from the generator to the strut
that connects the rotor assembly to the support structure.
Figure 19: Power-train Design
While the dimensions of the rotor and screen are a function of the rotor diameter, the generator
housing is largely a function of power rating. The following table provides the generator
housing dimensions at various rated capacities (Dimension A and B in above sketch).
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Table 2: Powertrain housing specifications
Rated Capacity Housing diameter (A) Housing length (B) Weight
0.5kW 200mm 500mm 13.6 kg
2 kW 400mm 1000mm 18.1 kg
5 kW 600mm 1500mm 25 kg
A protective screen is required for sites that have a high amount of debris suspended in the water
column. The protective screen is built from a ½ inch round stainless steel bar to withstand the
impact of debris pieces. The screen is mounted onto the generator housing. A front-view and a
side-view of the screen are shown below.
Figure 20: Protective screen
AP&T has designed a similar pontoon-type device with a trash rack mounted on its front end
which may be a more robust alternative to the design described herein. The rotor may also need
a fish screen as shown in the illustration below. Detailed design requirements for these elements
are unknown at present because there is no operational experience yet available.
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Figure 21: Example of fish screen
3.6. Investigation of Design Alternatives
Power-train topology alternatives to the base case described above were investigated in respect
to their cost-reduction potential and impact on lowering O&M cost. The following sections
provide a brief review of these options. The costs evaluated in this report refer to the baseline
design, not any of the alternative topologies outlined.
Removal of the speed-increaser gearbox and use of a low-rpm direct-drive generator: Material
cost of permanent magnet generators scales directly to the peak torque it generates given a
particular generator topology. Power is the product of torque and rotational speed (rpm).
Because rotor rpm is limited by the rotor’s tip-speed, smaller rotors can operate at higher rpm
and therefore make direct drive permanent magnet topologies more attractive from a cost point
of view. Some generic cost studies on gearboxes also revealed that they tend to be more costly
at smaller sizes, making them an unattractive alternative at lower power ratings. Gearboxes also
tend to be somewhat unreliable. Eliminating the need for a gearbox has the potential to
significantly improve the overall system’s reliability.
Use of a fluid-filled PM generator design, allowing the elimination of seals that otherwise would
be required with a water-tight enclosure:
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Various PM direct drive machines have been built as “wet” designs for applications such as ship-
propulsion and submersible design. Instead of an air-gap between the stator and the rotor of the
machine, the gap is simply filled with fluid. This option could reduce the cost of the enclosure
significantly and provide for a potentially more reliable overall design.
Operating the unit at fixed speed, thereby eliminating the need for a frequency converter: This
proves to be a useful design alternative for sites that have very consistent fluid velocities; as a
result, variable speed operation would only minimally increase energy production. The
elimination of a frequency converter can reduce the overall system cost significantly.
Placing the frequency converter on-shore:
The rotor speed at which maximum efficiency is achieved is a direct function of the water
velocity. Multiple units deployed in the same area are going to be subjected to very similar flow
conditions (although there may be minor variations in flow locally). Thus, the optimal rotational
speed and resulting AC frequency coming from the different generators is the same for all the
rotors. This makes it possible to connect all the machines to the same cable and locate the
frequency converter onshore. This option would reduce the complexity of the equipment located
on the pontoon barge and provide the ability to place the frequency converter onshore into a
protected environment without compromising efficiency.
Reduction of structural loads by use of furling mechanism:
Furling is used by small wind turbines to reduce the loads on the turbine. A wind-turbine or
RISEC rotor is typically perpendicular to the fluid flow. A furling mechanism typically consists
of a spring or weight-controlled mechanism that allows rotor to rotate out of that perpendicular
direction, and therefore reduces the frontal area intersecting the fluid flow. The result is reduced
power absorption, but also reduced loads on the rotor, which is favorable in conditions where it
does not make economic sense to extract the additional power. This type of mechanism does not
add much cost, but could reduce peak structural design loads significantly and therefore reduce
cost.
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3.7. Integrated Modeling
Integrated modeling is an approach that allows a rapid evaluation of different generation options
and design alternatives. The basic concept is that changing one design aspect will have a ripple
effect in terms of both cost and design to other components within the overall system. The
following displays the elements of such an integrated model.
For the purpose of this study the conceptual designs served as the foundation to establish cost
estimates of the technology, which were then used in an established integrated modeling
framework.
3.8. Uncertainties in cost predictions
For emerging renewable energy technologies such as RISEC, the only pathway to estimate
project costs (and underlying economics) for a plant is by modeling technology-related
parameters. Costs can then be estimated based on historical quotes and projects in related
technology fields and projects. This approach introduces a significant amount of uncertainties,
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especially with technologies that have not yet been tested at full scale. Manufacturers typically
underestimate cost in the early stages of development, and as the technology’s maturity moves
towards commercial maturity, such cost-projections increase. The actual build and operational
cost of a pilot device or a pilot RISEC-farm will then reveal a complete cost picture and provide
a solid starting point for further cost-studies. Once a technology reaches commercial maturity,
volume production will begin driving down cost.
The following figure shows the typical cost projection as a function of design maturity.
Cost
Stage of Development
Lab/Idea Prototype Commercial Volume
Production
Figure 22: Cost projection as a function of Development Status
Based on experience of estimating energy project cost, EPRI has developed a cost estimate
rating table which assesses the likely range of uncertainty based on the technology’s design
maturity and the amount of detail included in the cost estimate.
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Table 3 - EPRI cost estimate rating table
Using this table, the accuracy of the cost estimates for this project during the Feasibility Study is
expected to be:
• Initial capital cost – pilot stage of development and simplified cost estimate = -30 to
+30% accurate based on the existence of prototypes and the simplified cost estimate level
of detail for this project.
• Replacement and overhaul capital cost and O&M – conceptual stage of development and
simplified cost estimate = -30 to +80% accurate based on the lack of existing experience
with periodic replacement, overhaul and O&M.
The estimates will have a relatively high degree of uncertainty, particularly in the periodic
replacement, overhaul and O&M area.
In addition to technology-related cost uncertainties, the cost for raw materials such as steel and
copper has increased significantly, and many relevant industries such as underwater cable
manufacturers have limited additional capacity to meet global infrastructure expansions. As a
direct result, end product costs are artificially inflated. A comparison of manufacturer quotes for
subsea cables between 2004 and 2007 revealed a cost increase of over 200% for a similar cable.
Other industries are affected by this trend as well. Wind energy costs reached an all-time low in
the year 2000 when the costs sank to about $1100 per installed kW. Since then, cost has steadily
increased and is now (2007) at over $1800 per installed kW. As a result of the above factors,
significant uncertainties in the prediction of cost remain, and any cost and/or economic
projections of these emerging technologies should be viewed with these factors in mind.
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4. Site Design
Extracting power from a river will have a feedback effect on the water flow in the river. The
following sections address turbine placement and the impact of energy extraction on the free-
flowing stream. Given the relatively low level of extraction, the feedback effects are likely to be
marginal for the sites of interest.
4.1. Turbine arrangement
Turbines are arranged in rows within the stream in the areas where the highest velocities are
present. The purpose of this study is not to determine the exact location where these turbines are
to be located, but to determine generic spacing assumptions and placement. Turbines will create
a cone-shaped wake behind themselves. For wind turbines, this wake typically extends about 10
rotor diameter, which determines the rows’ minimal downstream spacing. Wake effects for
water turbines are expected to be very similar. For a 2m rotor, this indicates a minimal row-to-
row spacing of 20m, within which distance the flow will recover to uniform flow conditions.
Rivers at the sites of interest show the highest velocities during summer months. However,
energy consumption in these villages is lowest during summer and highest in winter. For two of
the three sites under investigation (Igiugig and Eagle), the targeted generation capacity is
therefore set to summer levels. The difference in energy required at the site can be met using the
existing diesel generators. In Eagle, the required summer generation capacity is about 70kW and
in Igiugig about 40kW.
Because Whitestone is connected to the electric grid network, the upper grid interconnection
limits are higher. The 26kV line would likely allow for more than 10MW of power to be
connected to the grid. This would require a significant number of units to be deployed at the
site. It appears impractical at this point in time to evaluate such a large deployment scheme.
Instead, a nearer-term target of 30 units was used as a commercial design point. This design
point was chosen because of the following reasons:
1. Grid interconnection and other infrastructure cost components no longer play a dominant
role in the cost of the RISEC farm.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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2. Tooling cost can be shared across a sufficient production volume to reduce cost to a
commercial level. Increasing volume will yield only insignificant improvements in
commercial scale economics.
3. Energy extraction from the stream does not significantly reduce available kinetic energy
and therefore can be largely neglected in economic calculations. The next section will
describe the impacts of this in more detail.
As such, the commercial design near Whitestone does not represent the extractable upper limit of
this site, but is rather a design point representative of the cost profile of a commercial plant at the
site.
5. Results for Igiugig on the Kvichak River
The community of Igiugig is located at the head of the Kvichak River as it drains out of Lake
Iliamna. Igiugig is a small village (population 56) located in southwestern Alaska, on the south
bank of the mouth of the Kvichak River and Lake Iliamna. The village is 48 miles southwest of
Iliamna, Alaska, and 56 miles northeast of King Salmon, Alaska. The Village's population
consists mainly of Yupik Eskimos, Aleuts, and Athabascan Indians. The map below shows the
likely deployment location (red rectangle). Grid interconnection opportunities exist near the
shoreline for such a plant. The site is ice-free through the winter. However, during spring
breakup turbines would need to be removed to protect them from ice-chunks that come from
Lake Iliamna.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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100m
1’: 3.41fps
4’: 4.26fps
6’: 4.21fps
box A
Tract H1
1’:4.90fps
4’:4.98fps
5’:4.30fps
box C
1’: 7.42fps
4’: 6.39fps
8’: 5.47fps
box B
Figure 23: Community Profile Map and Water velocity readings at proposed site: June 20th 2007
The village of Iguigig has three generators ranging from 60 to 100kW that work independently
per load, as necessary to energize the community’s 7200-volt three-phase distribution system
installed in two phases, 1998 and 2002.
Tract H1 (see Figure 22) contains the community powerhouse/bulk fuel facility and illustrates
the optimal location of the powerhouse to the river/hydro source for generation and distribution
(all within 200’ of the rivers edge). Historical load patterns range from 40kW to 95kW with the
coldest months of December, January and February requiring the greatest peak load demands.
However some of the peak-loads come from running the diesel generators at capacity to clean
them out. Diesel generators running below their rated capacity for extended periods of time tend
to During that period the loads are dumped over load banks.
Currently Igiugig has 56 year-round residents with a summer population of 75, and provides
goods and services to six area tourism lodges and their respective clientele and workforce of 90
additional persons per week.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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As with most of the Alaskan villages, the village’s electrical demand is lowest during summer
and highest during winter. The Kvichak River, on the other hand, shows the highest discharge
rates and related power-densities during summer months. For this site, a RISEC plant feeding
power into the isolated grid at Iguigig is rated at 40kW.
The following illustrations show the river cross-sectional profile and the depth averaged
velocity. It shows that the river is relatively shallow and velocities are highest in the middle of
the channel. Another factor to be considered is that velocity tends to be highest near the surface
and decrease with depth.
-4.0
-3.5
-3.0
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
0 20 40 60 80 100 120 140 160 180
Distance from shore (m)Water Depth (m)
Figure 24: River cross-sectional profile at annual average discharge rate
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
0 20 40 60 80 100 120 140 160 180
Dis tance from s hore (m )Velocity (m/s)
Figure 25: Depth-Averaged Velocity Distribution across river at annual average discharge rate
The water depth at the site of interest will likely limit the rotor size to 1.5m. Given this
limitation, a total of three machines with 4 x 1.5m diameter rotors are needed to reach the
electrical capacity of 40kW during summer peak flows. The following table summarizes the
specifications for the commercial plant to be deployed at the site of interest.
Table 4: Technical Parameters
Machine Parameters
# Rotors per RISEC device 4
Rotor Diameter 1.5m
Rotor Cross-Sectional Area 1.8m2
RISEC device Width 7.5m
# Rows of machines 1
Array Parameters
# RISEC machines 3
Array Width 50m
Array Length (incl. Moorings) 50m
Total Rotor Cross-Sectional Area 21.2m2
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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Velocity distributions for each month of the year were generated based on USGS velocity
calibration data and historical discharge rates, against which device performance data could be
mapped. The following shows the velocity distribution at the site, which was used to calculate
machine performance.
Table 5: Monthly Frequency Distributions at the deployment site
Monthly average power production values for the commercial plant consisting of three RISEC
devices were calculated; the results are presented in the graph below, showing the
summer/winter variability of the resource at the site.
0
5
10
15
20
25
30
35
40
45
Jan Feb Mar Apr May Jun Jul Aug S ep Oc t Nov Dec
MonthMonthly Average Electrical Power (kW)
Figure 26: Monthly Average Power Output of 40kW rated RISEC farm (load limiting month is
August)
An alternative to this first scenario of rating the plant to summer conditions would be to rate the
RISEC plant so that it is able to deliver a constant base-load of 40kW over the entire year. This
is possible at this particular site because the variation of flows is not quite as high as some of the
other river sites of interest. The RISEC machines are de-rated by shedding excess power during
summer months. To accomplish that, it would take a total of 9 RISEC machines. The following
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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graph shows the monthly average output of such an array. The capacity factor of this array is
98%.
0
5
10
15
20
25
30
35
40
45
Jan Feb Mar Apr May Jun Jul Aug Sep Oc t Nov Dec
MonthAverage Electrical Power (kW)
Figure 27: Monthly Average Electrical Power Output for 9-unit RISEC plant rated at 40kW.
5.1. Pilot Plant Cost
The primary purpose of a pilot plant is to gain technical, environmental and commercial
confidence in a technology. For the purpose of doing so, a single pontoon unit with two counter-
rotating 1.5m diameter rotors is proposed. This same unit will be able to accommodate a total of
four rotors, but in order to reduce the cost for the pilot the unit is equipped with only two rotors.
The following shows the cost and performance numbers for this single machine.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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Table 6: Pilot Plant cost and performance (2007 $)
5.2. Commercial Plant Performance and Cost
Costs for the commercial plant are, as for most renewable energy generating technologies,
heavily weighted towards up-front capital. In order to determine the major cost centers of the
commercial plant and assess them properly in the context of the given site conditions, detailed
cost build-ups were created. There are a few major influences impacting the relative economic
cost at a particular site, as discussed below:
Design Current Speed: The design current speed is the maximum velocity of the water expected
to occur at the site. Structural loads (and related structural cost) increase to the second power of
the fluid velocity. Given the velocity distribution at the site, the design velocity can be well
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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above the velocity at which it is economically useful to extract power. In other words, the
design velocity can have a major influence on the cost of the structural elements. For
conservatism, the design velocity is set to 120% of the peak velocity measured at the site.
Velocity Distribution: The velocity distribution at the deployment site is illustrated in earlier
chapters in this report. They detail the river current velocities at which there is a useful number
of reoccurrence to pay for the capital cost which is needed to tap into this velocity bin. The
velocity distribution is then used to calculate the annual energy output of the machine at the
installation site. Rather than make assumptions as to where the appropriate rated velocity of the
RISEC device should be, an iterative approach was chosen to determine which rated speed of the
machine will yield the lowest cost of electricity at the particular site.
Number of installed units: The number of RISEC devices deployed has a major influence on the
resulting cost of energy. In general, a larger number of units will result in lower cost of
electricity. There are several reasons for this, as outlined below:
• Infrastructure cost required to interconnect the devices to the electric grid can be shared,
therefore lowering their cost per unit of electricity produced.
• Installation cost per turbine is lower because mobilization cost can be shared between
multiple devices. It is also apparent that the installation of the first unit is more
expensive than subsequent units, as the installation contractor is able to increase their
operational efficiency.
• Capital cost per turbine is lower because manufacturing of multiple devices will result in
reduction of cost. The cost of manufactured steel, for example, is very labor-intensive.
The cost of hot rolled steel plates as of July 2005 was $650 per ton. The final product,
however, can cost as much as $4500 per manufactured ton of steel. In other words, there
is significant potential to reduce capital cost by introducing more efficient manufacturing
processes. The capital cost for all other equipment and parts is very similar.
Device Reliability and O&M procedures: The device component reliability directly impacts the
operation and maintenance cost of a device. It is important to understand that not only does the
40
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
component need to be replaced, but the actual operation required to recover the component needs
to be included as well. Additional cost of the failure is incurred by the downtime of the device
and its inability to generate revenues by producing electricity. The access arrangement plays a
critical role in determining what kind of maintenance strategy is pursued and the resulting total
operation cost.
Insurance cost: The insurance cost can vary greatly depending on the project risks. This is
especially true with un-tested technologies such as RISEC. No insurance cost was included for
the purpose of this study.
Permitting, detailed design and environmental monitoring cost: These cost components are
difficult to estimate and are not included in this study. They could be substantial, especially for
the first deployments.
The following two tables present a cost breakdown of a commercial RISEC farm at the two
deployment sites.
41
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Table 7: Cost and performance of a 3-unit array at Igiugig site (cost in 2007 dollars)
A second potentially attractive option, which would provide the village with baseload power
over the whole year, is shown in the following table. In order to accomplish this, excess power
is shed during periods of high flows.
42
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Table 8: Iguigig plant configured to provide a constant output over the whole year (base-load)
43
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
5.3. Feedback Effects on Flow
A 1-D model was used to investigate the feedback effects of extracting energy from the river.
The velocity reduction as a result of extracting energy from the river in Iguigig proved to be so
small that it will likely not be measurable. The following two tables show the inputs to the
model. Extraction effects were modeled for a typical average flow condition at the deployment
site. Background information on the 1D modeling approach is offered in appendix A.
Table 9: Turbine Parameters
Rotors/machine 4
Machines/row 3
Rows 1
Total rotors 12
Diameter 1.5m
Extraction efficiency 40%
Table 10: Site Parameters
Velocity 1.39m/s
Depth 2.4m
Width 152m
Length 800m
Elevation Change 0.6m
Manning roughness 0.035
It is assumed that the extraction will not alter the river flow rate. The case described extracts 23
kW from the flow and increases the river depth by 6mm. Given natural flow variability for the
site, this change is probably not measurable. The respective changes to flow velocity and power
density are also negligible.
Along-channel velocity and depth profiles for the site are shown in Figure 28 and Figure 29. It
should be noted that the gradients across rows of turbines will probably not be as sharp as those
portrayed here using a 1-D assumption, but the profile will be generally saw-toothed. For all
cases tested, velocity increases across each transect and depth decreases, indicating an exchange
of kinetic and potential energy in the system. Note, however, that the variations are quite small
relative to their mean values.
44
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
1.385
1.385
1.386
1.386
1.387
1.387
1.388
1.388
1.389
0 100 200 300 400 500 600 700 800 900
Dis tance from Inle t (m)Velocity (m/s)
Figure 28 – Iguigig at Kvichak: velocity profile, 12 rotors – 23 kW extraction
2.403
2.404
2.405
2.406
2.407
2.408
2.409
2.410
0 100 200 300 400 500 600 700 800 900
Dis tance from Inle t (m)Depth (m)
Figure 29 – Iguigig at Kvichak: depth profile, 12 rotors – 23 kW extraction
45
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
5.4. Economic Analysis
A Simple Payback Period (SPP) refers to the period of time required for the return on an
investment to "repay" the sum of the original investment. For example, a $1000 investment
which returned $500 per year would have a two-year payback period. It intuitively measures
how long something takes to "pay for itself"; shorter payback periods are obviously preferable to
longer payback periods. The results of the SPP calculation for Iguigig show a 3-4 year payback
period. The calculation assumes installation in 2009 and beginning of operation Jan 1, 2010.
The installation year is counted as part of the payback period. The breakdown of the analysis is
shown in the table below.
Table 11: SPP calculation for baseline scenario
To illustrate the above table further, Figure 30 shows the cumulative cost and the cumulative
revenue as a function of time. The simple payback period is defined by the point where the
cumulative revenues equal or exceed the cumulative cost. and where 2009 is counted as the first
year. the payback period is 3 to 4 years.
46
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
$0
$500,000
$1,000,000
$1,500,000
$2,000,000
$2,500,000
$3,000,000
2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
Y ear
Cum ulative Cos t Cum ulative Revenue
Figure 30: Cumulative cost vs. cumulative revenue
A secondary scenario was investigated to provide baseload power to the village. The payback
period for that scenario is also 3 to 4 years. The following table shows the SPP analysis of that
scenario and Figure 31 shows the cumularive costs and revenues over time..
Table 12: Baseload Scenario for Iguigig Village
47
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
$0
$500,000
$1,000,000
$1,500,000
$2,000,000
$2,500,000
$3,000,000
$3,500,000
$4,000,000
$4,500,000
$5,000,000
2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
Y ear
Cum ulative Cos t Cum ulative Revenue
Figure 31: Cumulative cost vs. cumulative revenue
48
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
6. Results for Eagle on the Yukon River
Eagle is located on the west bank of the Yukon River, on the north terminus of the Taylor
Highway and about 6 miles west of the Alaska-Canada border. Eagle Village, at about 850 feet
above sea level, is located approximately 3 miles upriver from the City of Eagle. Alaska Power
and Telephone (AP&T) is actively investigating RISEC technology and has done a significant
amount of groundwork for that site. This data was not available at the time of writing this report
and was therefore not included. The velocity data in this report was calibrated using USGS data,
which was not taken directly at the project location. Background on AP&T’s work can be found
in their FERC Draft Pilot license application, which can be downloaded from their website at
www.aptalaska.com.
The Yukon River is located in the interior region of Alaska. The Tanana and Chena River flow
into the Yukon. The river starts in the Yukon, Canada, and flows through Alaska, emptying into
the Bering Sea. The Yukon is one of the largest rivers in North America. The river is very
remote with only a few dozen sizeable communities along its entire length. The river was a
highway for prospectors during gold rush days (1890s) and continues to be an important river
highway. Due to glacial run-off, the waters of the Yukon are silty during most of the year.
Eagle has a state-owned airstrip with commercial flights from Fairbanks, which provides access
to this remote community all year long. In summer the small community is also accessible by
river boat and via the Taylor Highway.
49
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Figure 32: View onto village and Deer Island
AP&T serves about 190 customers in the two communities (Eagle Village and City of Eagle),
providing electricity and communication services. The isolated grid has average loads of 70kW
in summer and 150kW in winter. Diesel generators are used to generate electricity and annually
consume 57,000 gallons of fuel.
As with all of the Alaskan villages, the village’s electrical demand is lowest during summer and
highest during winter. The Tanana River, on the other hand, shows the highest discharge rates
and related power-densities during summer months. This means that a RISEC plant feeding
power into the isolated grid at Eagle will need to be rated at the summer capacity low, which is
about 70kW.
The river normally begins to freeze in October, freezing to solid ice with a thickness of 4-8
feet. There is also a frazil ice-layer below the solid ice. Ice breakup normally occurs in April
50
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
and clears by May. This breakup is potentially destructive, with large pieces of ice scouring
the river bottom and edges.
The following two illustrations show the river’s cross-sectional profile and the velocity
distribution across the river. They show that the river is fairly deep with the highest velocities
about 150m from shore. The depth would potentially allow for devices being located below
the ice in winter. However, the low discharge rates during winter and the fact that velocities
are concentrated near the river surface combine to make operation impractical during the
winter. Devices will be deployed at the end of the ice-breakup in early May and recovered
before freeze-over in early October, giving about 5 months of operational time each year.
-12.0
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
0 50 100 150 200 250 300 350 400 450 500
Dis tanc e from s hore (m)Water Depth (m)
Figure 33: Cross sectional profile at USGS calibration site at annual average discharge rate
51
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
0.00
0.50
1.00
1.50
2.00
2.50
3.00
0 50 100 150 200 250 300 350 400 450 500
Dis tanc e from s hore (m )Velocity (m/s)
Figure 34: Cross sectional variation in depth-averaged velocity at USGS calibration site at
annual average discharge rate
The following aerial view shows the likely project location (shown in red). Grid
interconnection options are plentiful near the shoreline, by either tapping into a distribution
line or building a line extension directly from the shoreline to the substation.
200m
Figure 35: Likely site location (shown in red)
52
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Micro-siting activities may reveal better power densities a few hundred yards up or down the
river and the project deployment location could be adjusted accordingly. Based on the above
site-constraints, the following table shows the specifications for a commercial-sized machine
that would produce about 60kW at rated capacity.
Table 13: Technical Parameters
Machine Parameters
# Rotors per RISEC device 4
Rotor Diameter 2m
Rotor Cross-Sectional Area 3.1 m2
RISEC device Width 10 m
# Rows of machines 1
Array Parameters
# RISEC machines 1
Array Width 10m
Array Length (incl. Moorings) 50m
Total Rotor Cross-Sectional Area 12.5m2
Monthly velocity frequency distributions for the site of interest were derived based on
historical USGS discharge rates and calibration parameters. The following table shows the
monthly frequency distributions of velocities for that site. It is important to remember that
these velocities are applicable for the particular measurement transect the USGS has chosen to
calibrate the discharge rates of the river. Velocities and associated power densities can vary
depending on the exact project location.
53
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Table 14: Monthly frequency distributions for cross-section average velocities at the site
Velocities vary throughout the profile of any particular cross-section. The comparison of data
from different rivers showed that in natural rivers, the peak velocity in a particular cross-
section is about 30% higher than the average velocity. In order to attain proper velocity
distributions for a likely deployment site, channel-average velocity was multiplied by a factor
of 1.3.
Based on these velocity distributions, the commercial machine’s monthly average power
production was calculated. The following graph shows the machine output over a typical year.
0
10
20
30
40
50
60
70
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
MonthAverage Electrical Power (kW)
Figure 36: Monthly average power production
54
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
The above figure shows that power production during the winter months under the ice do not
add a lot of value to the system. Initial trade-off analysis suggests that not only are the winter
months in this location highly un-productive, the complete submersion of the device would
also bring the device near the river-bed, where velocities are lowest. This would further
reduce overall power production and affect the economic viability negatively. Therefore it was
decided that the devices would be deployed after the ice breakup in May and removed in early
October before the ice freezes over, providing about 5 months of continued operation.
6.1. Pilot Plant Cost
The primary purpose of a pilot plant is to gain technical, environmental and commercial
confidence in a technology. For the purpose of doing so, a single pontoon unit with 2 counter-
rotating 2m diameter rotors is proposed. This same unit will be able to accommodate a total of 4
rotors, but in order to reduce the cost for the pilot the unit is equipped with only two rotors. The
following shows the cost and performance numbers for this single machine.
Table 15: Cost and Performance of Pilot Unit at Eagle (2007 $)
55
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
6.2. Commercial Plant Performance and Cost
Costs for the commercial plant are, as for most renewable energy generating technologies,
heavily weighted towards up-front capital. In order to determine the major cost centers of the
commercial plant and assess them properly in the context of the given site conditions, detailed
cost build-ups were created. There are a few major influences impacting the relative economic
cost at a particular site, as discussed below:
Design Current Speed: The design current speed is the maximum velocity of the water expected
to occur at the site. Structural loads (and related structural cost) increase to the second power of
the fluid velocity. Given the velocity distribution at the site, the design velocity can be well
above the velocity at which it is economically useful to extract power. In other words, the
design velocity can have a major influence on the cost of the structural elements. For
conservatism, the design velocity is set to 120% of the peak velocity measured at the site.
Velocity Distribution: The velocity distribution at the deployment site is illustrated in earlier
chapters in this report. They detail the river current velocities at which there is a useful number
of reoccurrence to pay for the capital cost which is needed to tap into this velocity bin. The
velocity distribution is then used to calculate the annual energy output of the machine at the
installation site. Rather than make assumptions as to where the appropriate rated velocity of the
RISEC device should be, an iterative approach was chosen to determine which rated speed of the
machine will yield the lowest cost of electricity at the particular site.
56
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Number of installed units: The number of RISEC devices deployed has a major influence on the
resulting cost of energy. In general, a larger number of units will result in lower cost of
electricity. There are several reasons for this, as outlined below:
• Infrastructure cost required to interconnect the devices to the electric grid can be shared,
therefore lowering their cost per unit of electricity produced.
• Installation cost per turbine is lower because mobilization cost can be shared between
multiple devices. It is also apparent that the installation of the first unit is more
expensive than subsequent units, as the installation contractor is able to increase their
operational efficiency.
• Capital cost per turbine is lower because manufacturing of multiple devices will result in
reduction of cost. The cost of manufactured steel, for example, is very labor-intensive.
The cost of hot rolled steel plates as of July 2005 was $650 per ton. The final product,
however, can cost as much as $4500 per manufactured ton of steel. In other words, there
is significant potential to reduce capital cost by introducing more efficient manufacturing
processes. The capital cost for all other equipment and parts is very similar.
Device Reliability and O&M procedures: The device component reliability directly impacts the
operation and maintenance cost of a device. It is important to understand that not only does the
component need to be replaced, but the actual operation required to recover the component needs
to be included as well. Additional cost of the failure is incurred by the downtime of the device
and its inability to generate revenues by producing electricity. The access arrangement plays a
critical role in determining what kind of maintenance strategy is pursued and the resulting total
operation cost.
Insurance cost: The insurance cost can vary greatly depending on the project risks. This is
especially true with untested technologies such as RISEC. No insurance cost was included for
the purpose of this study.
Storage Cost: The device is in operation during only 5 months in the summer. No storage cost
was added to account for winter storage of these machines.
57
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Permitting, detailed design and environmental monitoring cost: These cost components are
difficult to estimate and are not included in this study. They could be substantial, especially for
the first deployments.
The following table presents a cost breakdown of a commercial RISEC farm rated at 47kW at the
Eagle deployment site.
Table 16: Cost and performance of a single at Eagle site (cost in 2007 dollars)
58
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
6.3. Feedback Effects on Flow
A 1-D model was used to investigate the feedback effects of extracting energy from the river.
The velocity reduction as a result of extracting energy from the river in Eagle proved to be so
small that it will likely not be measurable. The following two tables show the inputs to the
model. Extraction effects were modeled for a typical average flow condition at the deployment
site. Background information on the 1D modeling approach is shown in appendix A.
Table 17: Turbine Parameters
Rotors/machine 4
Machines/row 2
Rows 1
Total rotors 8
Diameter 2.0m
Extraction efficiency 40%
Table 18: Site Parameters
Velocity 1.15m/s
Depth 6.8m
Width 464m
Length 1000m
Elevation Change 0.13m
Manning roughness 0.035
It is assumed that the extraction will not alter the river flow rate. The case described extracts 17
kW from the flow and increases the river depth by 8mm. Given natural flow variability for the
site, this change is probably not measurable. The attendant changes to flow velocity and power
density are also negligible.
Along-channel velocity and depth profiles for the site are shown in Figure 37 and Figure 38. It
should be noted that the gradients across rows of turbines will probably not be as sharp as those
portrayed here under a 1D assumption with discontinuous extraction, but the profile will be
59
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
generally saw-toothed. For all cases tested, velocity increases across each transect and depth
decreases, indicating an exchange of kinetic and potential energy in the system. Note, however,
that the variations are quite small relative to their mean values.
6.807
6.808
6.808
6.808
6.808
6.808
6.808
0 200 400 600 800 1000 1200
Dis tance fro m Inle t (m)Depth (m)
Figure 37 – Eagle at Yukon: depth profile, 8 rotors –17 kW extraction
1.146
1.146
1.146
1.146
1.146
1.146
1.146
1.146
1.146
1.146
1.146
0 200 400 600 800 1000 1200
Dis tance fro m Inle t (m)Velocity (m/s)
Figure 38 – Eagle at Yukon: velocity profile, 8 rotors –17 kW extraction
60
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
6.4. Economic Analysis
A Simple Payback Period (SPP) refers to the period of time required for the return on an
investment to "repay" the sum of the original investment. For example, a $1000 investment
which returned $500 per year would have a two-year payback period. It intuitively measures
how long something takes to "pay for itself"; shorter payback periods are obviously preferable to
longer payback periods. The calculation assumes installation in 2009 and beginning of operation
Jan 1, 2010. The installation year (2009) is counted as part of the payback period. The
breakdown of the analysis is shown in the table below. The results of the SPP calculation for
Eagle show a 4-5 year payback period.
Table 19: SPP Calculation for Eagle site
To illustrate the above table further, Figure 39 shows the cumulative cost and the cumulative
revenue as a function of time. The simple payback period is defined by the point where the
cumulative revenues equal or exceed the cumulative cost.
61
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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$0
$200,000
$400,000
$600,000
$800,000
$1,000,000
$1,200,000
$1,400,000
$1,600,000
2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
Ye a r
Cum ulative Cos t Cum ulative Revenue
Figure 39: Cumulative cost vs. cumulative revenue
62
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
7. Results for Whitestone on the Tanana River
The Whitestone community is located northwest of Delta Junction on the western side of the
Delta River near the town of Big Delta. The community has over 200 residents and is
represented by the Whitestone Community Association (WCA) in its work with State agencies
and other organizations. The Department Commerce and Community Development certified the
Whitestone Community Association as an unincorporated community for purposes of revenue
sharing for FY04.
Figure 40: Whitestone Community on the Tanana River
Boat Ramp
Richardson
Bridge
GVEA Grid
Whitestone
Community
Whitestone
Power Plant
Boat Ramp
700m
Figure 41: Site Overview
63
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
There are two main grid interconnection options. The first option is interconnecting directly to
the isolated grid of the Whitestone community; the second is to connect to the Golden Valley
Electric Association (GVEA) grid. The isolated grid at the Whitestone community has a
generator capacity of 390kW. A RISEC farm could be connected to the grid at 480V and
12.47kV. The remote portion of the GVEA Intertie, operating at 12.47kV, will likely provide for
more substantial feed-in capacity, and could be connected at Mile 275 Richardson Highway.
The following table shows the average and peak loads on the Whitestone isolated grid.
Table 20: Whitestone Community Monthly Load Patterns
For the purpose of this design study, it was assumed that a RISEC plant is connected to the
GVEA grid. As such, the local village-load does not provide a hard limit to size generation
capacity against. It is likely that more than 5MW of RISEC power could be connected to the
utility grid near Whitestone. For the purpose of this design study, it was assumed that a total of
30 units (with 4 X 2m diameter rotors each) will be deployed at the site to form the commercial
base-case. The following figure shows the monthly average power production of that plant.
Table 21: Technical Parameters
Machine Parameters
# Rotors per RISEC device 4
Rotor Diameter 2m
Rotor Cross-Sectional Area 3.1m2
RISEC device Width 10m
# Rows of machines 10
64
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Array Parameters
# RISEC machines 30
Array Width 50m
Array Length (incl. Moorings) 500m
Total Rotor Cross-Sectional Area 377m2
The following two illustrations show the river’s cross-sectional profile and the velocity
distribution across the river. They show that the river is fairly deep, with the high velocities at
less then 50m from shore. According to local sources, portions of the river stay ice-free for the
whole year. This would allow for year-round operation of RISEC devices at the site.
-14.0
-12.0
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
0 20 40 60 80 100 120 140 160 180
Dis tance from s hore (m)Water Depth (m)
Figure 42: River cross-sectional profile at Whitestone at annual average discharge rate
65
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
0.0
0.5
1.0
1.5
2.0
2.5
0 20 40 60 80 100 120 140 160 180
Dis tance from s hore (m )Velocity (m/s)
Figure 43: Depth-averaged cross-sectional velocity distribution at site near Whitestone at annual
average discharge rate
Based on historical USGS discharge rates and calibration parameters, monthly velocity
frequency distributions for the site of interest were derived. The following table shows the
monthly frequency distributions of velocities for that site. It is important to remember that
these velocities are applicable for the particular measurement transect the USGS has chosen to
calibrate the discharge rates of the river. Velocities and associated power densities can vary
depending on the exact project location.
Table 22: Monthly frequency distribution of velocities at site near Whitestone
Velocities vary throughout the profile of any particular cross-section. The comparison of data
from different rivers showed that in natural rivers, the peak velocity in a particular cross-
section is about 30% higher than the average velocity. In order to attain proper velocity
distributions for a likely deployment site, they were multiplied by a factor of 1.3.
66
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Based on these velocity distributions, the commercial machine’s monthly average power
production was calculated. The following graph shows the machine output over a typical year.
0
100
200
300
400
500
600
Jan Feb Mar A pr May Jun Jul Aug Sep Oct Nov Dec
MonthAverage Electrical Power (kW)
Figure 44: Monthly average electrical power production from commercial RISEC plant near
Whitestone
The above graph shows that electrical production levels in winter are quite low, because the
discharge rates of this river are quite low during the winter months.
7.1. Pilot Plant Cost
The primary purpose of a pilot plant is to gain technical, environmental and commercial
confidence in a technology. For the purpose of doing so, a single pontoon unit with two counter-
rotating 1.5m diameter rotors is proposed. This same unit will be able to accommodate a total of
four rotors, but in order to reduce the cost for the pilot the unit is equipped with only two rotors.
The following shows the cost and performance numbers for this single machine.
67
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Table 23: Pilot Plant Performance and Cost at Whitestone (2007 $)
7.2. Commercial Plant Performance and Cost
Costs for the commercial plant are, as for most renewable energy generating technologies,
heavily weighted towards up-front capital. In order to determine the major cost centers of the
commercial plant and assess them properly in the context of the given site conditions, detailed
cost build-ups were created. There are a few major influences impacting the relative economic
cost at a particular site, as discussed below:
Design Current Speed: The design current speed is the maximum velocity of the water expected
to occur at the site. Structural loads (and related structural cost) increase to the second power of
68
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
the fluid velocity. Given the velocity distribution at the site, the design velocity can be well
above the velocity at which it is economically useful to extract power. In other words, the
design velocity can have a major influence on the cost of the structural elements. For
conservatism, the design velocity is set to 120% of the peak velocity measured at the site.
Velocity Distribution: The velocity distribution at the deployment site is illustrated in earlier
chapters in this report. They detail the river current velocities at which there is a useful number
of reoccurrence to pay for the capital cost which is needed to tap into this velocity bin. The
velocity distribution is then used to calculate the annual energy output of the machine at the
installation site. Rather than make assumptions as to where the appropriate rated velocity of the
RISEC device should be, an iterative approach was chosen to determine which rated speed of the
machine will yield the lowest cost of electricity at the particular site.
Number of installed units: The number of RISEC devices deployed has a major influence on the
resulting cost of energy. In general, a larger number of units will result in lower cost of
electricity. There are several reasons for this, as outlined below:
• Infrastructure cost required to interconnect the devices to the electric grid can be shared,
therefore lowering their cost per unit of electricity produced.
• Installation cost per turbine is lower because mobilization cost can be shared between
multiple devices. It is also apparent that the installation of the first unit is more
expensive than subsequent units, as the installation contractor is able to increase their
operational efficiency.
• Capital cost per turbine is lower because manufacturing of multiple devices will result in
reduction of cost. The cost of manufactured steel, for example, is very labor-intensive.
The cost of hot rolled steel plates as of July 2005 was $650 per ton. The final product,
however, can cost as much as $4500 per manufactured ton of steel. In other words, there
is significant potential to reduce capital cost by introducing more efficient manufacturing
processes. The capital cost for all other equipment and parts is very similar.
69
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Device Reliability and O&M procedures: The device component reliability directly impacts the
operation and maintenance cost of a device. It is important to understand that not only does the
component need to be replaced, but the actual operation required to recover the component needs
to be included as well. Additional cost of the failure is incurred by the downtime of the device
and its inability to generate revenues by producing electricity. The access arrangement plays a
critical role in determining what kind of maintenance strategy is pursued and the resulting total
operation cost.
Insurance cost: The insurance cost can vary greatly depending on the project risks. This is
especially true with untested technologies such as RISEC. No insurance cost was included for
the purpose of this study.
Permitting, detailed design and environmental monitoring cost: These cost components are
difficult to estimate and are not included in this study. They could be substantial, especially for
the first deployments.
The following two tables present a cost breakdown of a commercial RISEC farm at the two
deployment sites.
70
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
_______________________________________________________________
Table 24: Cost and performance of a 30-unit array at Whitestone site (cost in 2007 dollars)
Whitestone is planning to connect to the GVEA grid, however it is presently not grid connected.
A second scenario was created by assuming the electricity grid at Whitestone is not grid-
connected. Therefore a capacity limit was superimposed onto this scenario. The following table
shows the results.
71
System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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Table 25: Isolated grid scenario for Whitestone village
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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7.3. Feedback Effects on Flow
A 1D model was used to investigate the feedback effects of extracting energy from the river.
The velocity reduction as a result of extracting energy from the river in Whitestone proved to be
significant enough to require incorporation of feedback effects into the device performance
model. The following two tables show the inputs to the model. Extraction effects were modeled
for a typical average flow condition at the deployment site. Background information on the 1D
modeling approach is offered in appendix A.
Table 26: Turbine Parameters
Rotors/machine 4
Machines/row 3
Rows 10
Total rotors 120
Diameter 2.0m
Extraction efficiency 40%
Table 27: Site Parameters
Velocity 0.979m/s
Depth 6.7m
Width 169m
Length 500m
Elevation Change 0.051m
Manning roughness 0.035
It is assumed that the extraction will not alter the river flow rate. The case described extracts 123
kW from the flow and increases the river depth by over 50cm. This is a meaningful change and
is accompanied by a substantial drop in kinetic power density (~20%) at the site. This may have
economic implications for site build-out.
Along-channel velocity and depth profiles for the site are shown in Figure 45 and Figure 46. It
should be noted that the gradients across rows of turbines will probably not be as sharp as those
portrayed here under a 1D assumption with discontinuous extraction, but the profile will be
generally saw-toothed. For all cases tested, velocity increases across each transect and depth
decreases, indicating an exchange of kinetic and potential energy in the system. Note, however,
that the variations are quite small relative to their mean values.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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7.241
7.242
7.242
7.242
7.242
7.242
7.243
7.243
0 100 200 300 400 500 600
Dis tance from Inle t (m)Depth (m)
Figure 45 – Whitestone at Tanana: depth profile, 120 rotors –123 kW extraction
0.906
0.906
0.906
0.906
0.906
0.906
0.906
0.906
0.906
0 100 200 300 400 500 600
Dis tance from Inle t (m)Velocity (m/s)
Figure 46 – Whitestone at Tanana: velocity profile, 120 rotors –123 kW extraction
Since this level of extraction does meaningfully alter the inlet depth of the river and the flow
regime (velocity and power density), it is worth considering the effects for different levels of
extraction. The increased inlet depth corresponds to a reduced inlet velocity with the volume
flow rate held constant (Figure 47).
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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y = 5.942E-04x
R2 = 9.993E-01
0%
1%
2%
3%
4%
5%
6%
7%
8%
0 20 40 60 80 100 120 140
A rray E x t rac t io n (k W)Inlet Velocity Reduction (%)
Figure 47 – Channel velocity reduction (cross-sectional average) as a function of extraction
Since power density is proportional to the cube of velocity, its reduction is more pronounced.
(Figure 48).
y = 1.678E-03x
R2 = 9.998E-01
0%
5%
10%
15%
20%
25%
0 20 40 60 80 100 120 140
A rray E x t rac t io n (k W)Inlet Power Density Reduction (%)
Figure 48 – Channel power density reduction (cross-sectional average) as a function of
extraction
Finally, the reduced power density decreases the output per rotor in a nearly linear manner as
extraction increases (Figure 49).
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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y = -2.167E-03x + 1.295E+00
R2 = 9.998E-01
1.000
1.050
1.100
1.150
1.200
1.250
1.300
0 20 40 60 80 100 120 140
A rray E x trac t io n (k W)Power Output/Rotor (kW)
Figure 49 – Power output per rotor as a function of extraction
For the cases considered, flow quantities and power output decline in a nearly linear manner. If
additional rows of turbines were added to flow, the decline would intensify (becoming quadratic
in nature), eventually reaching a point at which additional turbines would generate less power.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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7.4. Economic Analysis
A Simple Payback Period (SPP) refers to the period of time required for the return on an
investment to "repay" the sum of the original investment. For example, a $1000 investment
which returned $500 per year would have a two-year payback period. It intuitively measures
how long something takes to "pay for itself"; shorter payback periods are obviously preferable to
longer payback periods. The calculation assumes installation in 2009 and beginning of operation
Jan 1, 2010. The installation year (2009) is counted as part of the payback period. The
breakdown of the analysis is shown in the table below. The results of the SPP calculation for
Whitestone show a 8-9 year payback period.
Table 28: SPP Calculation for Whitestone
To illustrate the above table further, Figure 50shows the cumulative cost and the cumulative
revenue as a function of time. The simple payback period is defined by the point where the
cumulative revenues equal or exceed the cumulative cost.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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$0
$1,000,000
$2,000,000
$3,000,000
$4,000,000
$5,000,000
$6,000,000
2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
Y ear
Cum ulative Cos t Cum ulative Revenue
Figure 50: Cumulative cost vs. cumulative revenue
The secondary scenario for a smaller plant at Whitestone that is only connected to the local
isolated grid showed a payback period of 3-4 years. The following table shows SPP calculations
for that scenario.
Table 29: SPP Calculation for Whitestone Baseload Scenario
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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To illustrate the above table further, Figure 51 shows the cumulative cost and the cumulative
revenue as a function of time. The simple payback period is defined by the point where the
cumulative revenues equal or exceed the cumulative cost.
$0
$500,000
$1,000,000
$1,500,000
$2,000,000
$2,500,000
$3,000,000
$3,500,000
2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
Y ear
C u m u l a ti ve C o s t C u m u l a ti ve R e ve n u e
Figure 51: Cumulative cost vs. cumulative revenue
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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8. Conclusions
Conceptual RISEC design studies for three different sites in Alaska were carried out. The three
sites have very different site conditions affecting their viability. The conceptual site designs
were largely based on data that was collected in a previous site assessment study-phase. Results
of that study-phase are detailed in Reference 1. RISEC devices under development remain at an
immature stage of commercial development. In order to be able to carry out performance, cost
and economic assessments, EPRI established a baseline device design consisting of four rotors
mounted on a single pontoon structure. Based on that baseline design, a parametric cost and
performance model was established to be able to adapt the technology to the site conditions
encountered at the various sites of interest.
Iguigig Village located on the Kvichak River is a small community, where a RISEC plant could
be used to complement existing diesel-based generation. A RISEC plant at that site could be
continuously operated because the river at Iguigig remains ice-free throughout the year. During
ice breakup (about two weeks), the system would have to be removed to avoid damage. The
Kvichak River discharges water from the Llama Lake, which smoothes the summer/winter
variability of discharge rates. As a result, power densities do not drop off as much in winter time
as they do in other locations. The generation capacity of a commercial RISEC plant would be
limited to a summer usage low of 40kW.
The village of Eagle is a small community on the Yukon River, near the Canadian border. While
accessible by road during summer months, the village is not connected to an electrical grid and
generates its electricity using a diesel generator. The river at that location freezes over
completely during winter months. While the river is relatively deep and would potentially allow
for under-ice operation during winter months, the flow velocities during that time is so small that
it does not seem to make economic sense to generate power during these months. As a result it
was decided to plan for removal of the floating RISEC units before freeze-over and
redeployment after ice breakup in spring. This results in a period of five months during which
the plant would be operational.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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Whitestone Village located on the Tanana River is a small community located near the Big Delta
junction. The Richardson Hwy crosses the Tanana River just about one mile upstream from
Whitestone. An electrical transmission line (GVEA grid) runs alongside the highway which
could be used to export power from a potential RISEC generation site. While Whitestone is
presently not grid-connected, there are well-advanced plans to integrate the community into the
GVEA grid. While potentially more then 5MW of capacity could be exported from that location,
the baseline study focused on a deployment of a 500kW, 30 RISEC device plant. This allowed
evaluation of the impacts of commercial scale deployments.
The following table provides an overview of the high level results for the three sites. It is
important to understand that cost numbers shown in this report are reflecting installed machine
cost only. Additional cost incurred for permitting and environmental monitoring may result in
significant increases in cost for the first few installations.
Table 30: Site Summary
Iguigig Eagle Whitestone
Site Parameters
Ice freeze-over No Yes No
Annual Average Power Density 1.48 kW/m2 1.5 kW/m2 0.67 kW/m2
Mid-channel Average Power density 3.24 kW/m2 3.2 kW/m2 1.48 kW/m2
Average Total Kinetic Power 719 kW 4,601 kW 762 kW
Summer/Winter Power Density Variability 1:4 1:20 1:10
Site Distance from Shore 60 m 150 m 50 m
Grid Feed-In Limit 40 kW 70 kW > 5 MW
RISEC plant parameters
# of RISEC Devices 3 2 30
# Rotors per Machine 4 4 4
Rotor Diameter 1.5 m 2 m 2 m
Plant Rated Capacity 42 kW 61 kW 593 kW
Plant Annual Output 220 MWh/yr 113 MWh/yr 1325 MWh/yr
Capacity Factor 65 %57 % 29%
Availability 90%38%1 90%
Cost and Economic Parameters
Installed Cost $308,000 $269,000 $1,821,000
Installed Cost per kW $7,500/kW $5,800/kW $3,100/kW
Assumed Avoided Cost (selling price) 0.65 $/kWh 0.65 $/kWh 0.18 $/kWh
Simple Payback Period 3-4 Years 4-5 Years 8-9 Years
1 Availability for Eagle site is low because plant only operates during 5months of the year.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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River discharge rates and related hydrokinetic power densities are highest during summer
months when electrical loads in these villages is lowest. As a result the plant rated capacity was
sized to the daily average summer low to make sure that the electrical demand can absorb all the
power generated by these RISEC units. Hourly patterns (day/night) were however neglected and
it may require some additional battery storage to accommodate these hourly load fluctuations.
Additional scenarios were evaluated for the Whitestone and the Iguigig sites. The additional
scenario for Whitestone assumed that the plant would not be connected to the GVEA grid, but
instead is connected to an isolated Whitestone grid. This smaller capacity plant has a shorter
payback period then the larger grid-connected counterpart because present generation costs are
higher. However, it would not allow for the same scale of adoption because of the limited grid
feed-in capacity at the site. The second scenario for Iguigig aimed at providing base-load
capabilities for the site. This scenario showed an almost equal payback period.
Extracting power from a river has feedback effects on the flow within the river: fluid velocities
will slow down as a direct result of extracting power from the river and water levels increase. A
one-dimensional model was developed to simulate the effects of extracting power from the river.
The low level of extraction in Iguigig and Eagle will not affect flows in these rivers in any
measurable way. For the larger scale plant at Whitestone, a power-density reduction of about
7% was modeled during typical flow conditions. It is unlikely that this reduction will have any
significant environmental impact.
A parametric model was developed to evaluate the sensitivity of various cost and simple payback
period (SPP) parameters to the critical input parameter including rotor diameter, site power
density, number of rotors per machine and other parameters to determine what creates the
attributes for a good RISEC site. Because RISEC is an emerging technology with almost no
operational experience, evaluating what makes a good river site is one of the most important
aspects of a technical study such as this one. The following parameters have the most significant
impact on the cost of electricity from an in-stream device:
The higher the power density at the site, the more attractive the economics
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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Less variability in flow and power density at the site will result in higher capacity factors
and better economics.
Larger rotor sizes will yield better economics, requiring deeper water. Rotor sizes of 6ft
or more should be targeted. Vertical axis rotors could potentially prove advantageous in
shallow river sites but were not investigated as part of this study.
Significant uncertainties remain to be addressed in respect to actual operation of plants in the
three sites. The following are critical considerations to be addressed if any of the above villages
is to move forward with developing a site.
1. Velocities and power densities were established using USGS data. The USGS data was
not measured at the most likely deployment site and carries therefore a significant amount of
uncertainty, as velocities can change significantly within short distances in a particular river
reach. Before moving forward with a plant, a detailed bathymetric and velocity profiling survey
should be carried out at potential deployment locations.
2. Interaction of the machine with debris is an issue that is not well-understood at present.
There is little data on what type and how much debris is passing down the river at the sites of
interest. More importantly, cellulosic debris (such as logs) tend to float near the surface and it is
unclear to what extent such debris may also float in mid-water. Initial operational experience
will be needed to design potential mitigation measures.
3. The machine and rotor interaction with fish is not well-understood and will require
acoustic monitoring of fish movement around the turbines to evaluate the impacts of the machine
operation on the fish population.
4. This feasibility study assessed the cost of installed RISEC systems. However, with no
actual installations on which to base cost and performance data, cost uncertainties remain
significant, especially in respect to O&M activities.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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While many issues in respect to commercial deployment of RISEC devices remain to be
addressed, the results of this study indicate that this technology could be used to offset some of
the diesel generation in remote villages and could be attractive from an economic point of view.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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9. References
1. Previsic, M., Bedard, R., River In-Stream Energy Conversion (RISEC) Characterization
of Alaska Sites, EPRI – RP-003-Alaska
2. Selig, M. et al, “Wind Tunnel Aerodynamic Tests of Six Airfoils for Use on Small Wind
Turbines,” NREL/SR-500-34515, October 2004
3. Tangler, J., “NREL Airfoil Families for HAWTs,” NREL 1995
4. Somers, D., “The S822 and S823 Airfoils,” NREL January 2005
5. McTaggart, P., “Development of a Direct Drive Permanent Magnet Generator for Small
Wind Turbines,” Final Technical Report for the U.S. Department of Energy
6. Schulze, K., et al, “Simulating river flow on global scale,” Advances in Geosciences,
December 2005
7. Manwell, J., “Wind Energy Explained,” Theory, Design and Application, John Wiley and
Sons, 2002
8. Gipe, P., Wind Power - Renewable Energy from Home, Farm, and Business, Chelsea
Green Publishing Company, 2004
9. Burton, T. et al, Wind Energy Handbook, John Wiley and Sons, New York 2001
10. Hagerman, Polagye, Bedard and Previsic, “Methodology for Estimating Tidal Current
Energy Resources and Power Production by Tidal In-Stream Energy Conversion (TISEC)
Devices,” rev 3, Sep 29, 2006
11. Yukon River Hydrokinetic Turbine Project Eagle Alaska, Draft Pilot Project License
Application, February 5th, 2008. Available at www.aptalaska.com.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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10. Appendix A - River Extraction Model
In order to determine the effects of extraction for a particular site using a 1D model, the
following parameters must be known:
• Cross-sectional average velocity (U)
• Channel width (b)
• Channel depth (H)
• Channel length (L)
• Elevation change along channel length (∆z)
• Manning roughness coefficient (n)
These parameters are related via the Manning equation:
2132
⎟⎠
⎞⎜⎝
⎛∆=L
z
n
RUh (1)
where Rh is the hydraulic radius – the ratio of the cross-sectional area to wetted perimeter.
For the sites of interest in this study, only the velocity and channel geometry (width, depth,
length) parameters are known. However, using generally accepted Manning roughness
coefficients for natural channels (e.g. n=0.035), the elevation change for the channel may be
calculated through algebraic rearrangement of the Manning equation.
In order to model kinetic power extraction from a river, a number of simplifying assumptions are
made with respect to geometry and the underlying physics. It is assumed that the river channel is
a rectangular prism of constant width and downward slope (Figure 1). In a case without power
extraction, the accelerating effect of the downward slope (elevation distance from inlet to outlet)
is exactly counter-balanced by friction between the moving water and riverbed. As a result, the
river depth and velocity do not vary along its length.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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A. Profile View B. Cross-section View
Figure 1 - River Geometry
The flow is modeled in one dimension. That is, the flow is predominantly in the upstream and
downstream direction, with no variation in the cross-channel direction or depth. This
simplification significantly simplifies the physics involved.
Since the flow is at steady-state, the discretized form of the governing equations may be solved
by a marching technique. That is, for a given depth and velocity at an upstream position, it is
possible for the calculations to proceed downstream in discrete intervals. The discretized model
is shown in Figure 2, where the river has been broken into eight segments.
Figure 2 – Discretized River Geometry
Consider two points on the river (i=1 and i=2) separated by some distance (∆x). Between those
two points, mass and energy must be conserved. Since the density of the water is constant and
the system is assumed to be at a steady state, conservation of mass can be represented as
conservation of the flow rate (Q – m3/s) from station 1 to station 2.
QQQ==21 (2)
Depthinlet
Depthoutlet
River
Surface
River
Surface
River
Bed Elevationinlet River
Bed ElevationoutletReference Elevation
i=2 i=4 i=6 i=8
∆x
i=1 i=3 i=5 i=7
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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In order for energy to be conserved, the difference in kinetic and potential energy (total energy)
between stations 1 and 2 must match energy dissipated or added to the system between those two
stations.
()()Losses-Additions2
1
2
1
11
2
1
22
2
2
=+−⎟⎟
⎠
⎞
⎜⎜
⎝
⎛−++⎟⎟
⎠
⎞
⎜⎜
⎝
⎛zhbh
Q
gzhbh
Q
g (3)
- g: acceleration due to gravity (9.81 m/s2)
- h: water depth (m)
- z: elevation relative to reference datum (m)
For the river model, there are no additions of energy, and losses are due either to friction
between the flow and riverbed or extraction of kinetic energy. Losses due to friction are modeled
using another form of the manning equation:
xhb
Q
R
n
h
∆⎟⎠
⎞⎜⎝
⎛=
2
34
2
friction loss (4)
Losses due to energy extraction are modeled as removing a fraction of the upstream kinetic
energy:
2
1
extraction 2g
1 loss ⎟⎟
⎠
⎞
⎜⎜
⎝
⎛=bh
Qk (5)
- k: extraction coefficient – product of the rotor efficiency and blockage ratio
- blockage ratio: ratio of swept area of a row of turbines to the cross-sectional area of a
channel
It is assumed that turbines are distributed in transects (rows) spanning the channel. Transects are
evenly spaced along the channel. Since the channel center velocity tends to be greater than the
cross-sectional average velocity, an adjustment is made to the area of each turbine. The area is
increased such that the intercepted power under cross-sectional average flow conditions is equal
to the intercepted power for channel center velocity. This is a coarse approximation to account
for the actual location of turbines in the channel in determining the effect on the flow.
If the upstream depth, flow rate and elevation are known, and the downstream elevation is also
known, then equation (2) can be solved for downstream depth and the processes repeated for the
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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next segment of the discretized river. This method does not resolve the turbine wake or any
three-dimensional flow effects associated with turbine operation.
For the cases considered in this report, it is assumed that extraction will not change the volume
of water in the river channel, but rather increase the water depth at the inlet and reduce the cross-
sectional average velocity. Since this case is still at steady-state, the depths and velocities at the
channel inlet and outlet remain equal, though there is some variation over the rows of turbines as
shown in Figure 3.
0.947
0.947
0.947
0.948
0.948
0.948
0.948
0.948
0 100 200 300 400 500 600
Dis tance from Inle t (m)Velocity (m/s)6.923
6.924
6.924
6.925
6.925
6.926
0 100 200 300 400 500 600
Dis tance from Inle t (m)Depth (m)A. Channel Velocity B. Channel Depth
Figure 3 – Sample Output
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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11. Appendix B – RISEC Technologies under Development
Today, a number of entrepreneurial companies are leading the commercialization of in-stream
river energy conversion technologies. The table below presents known RISEC developers as of
July 31, 2008.
Table 21 River In Stream Energy Conversion Device Developers
Device Developer(1)
Website Device Name(2)Type(3)Development
Status(4)
AeroHydro Research and Technology
www.ahrta.com
Unknown Oscillatory Laboratory
Free Flow Power
www.freeflowpower.com
FFP Turbine
Generator
Horizontal Axis Experimental
Free Flow 69
www.hi-spec.uk.co/page10.htm
Osprey Vertical Axis Experimental
Lucid Energy
www.licidenergy.com
Gorlov Helical
Turbine (GHT)
Vertical Axis Technology
Demonstration
Hydro Green Energy
www.hgenergy.com
Krouse Turbine Horizontal Axis Experimental
New Energy Corporation
www.newenergycorp.ca
EnCurrent Turbine Vertical Axis Commercial
Demonstration
Ocean Renewable Power Corp
www.oceanrenewablepower.com
OCGen Crossflow Axis Technology
Demonstration
UEK
www.uekus.com
Underwater Electric
Kite
Horizontal Axis Commercial
Demonstration
Verdant Power
www.verdantpower.com
Free Flow Turbine Horizontal Axis Commercial
Demonstration
Vortex Hydro
www.vortexhhydro.com
VIVACI Vertical Axis Laboratory
(1) This list excludes individual inventors with conceptual level technology.
(2) Name given to the device.
(3) The principle of operation.
• HA – Horizontal Axis Open Rotor
• HA – Ducted Horizontal Axis
• VA – Vertical Axis
• Oscillatory
(4) The following definition of development status was used:
• Laboratory testing stage
• Experimental – Subscale at sea testing
• Technology Demonstration – Large size engineering prototype at sea testing whose purpose is to test for function
and performance
• Commercial Demonstration – Large size manufacturing prototype at sea testing whose purpose is to test for
commercial viability
• Early Commercial – Offering many units of large size for purposes of generating and selling the electricity produced
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Aero Hydro Research and Technology Associates
Aero Hydro Research and Technology Associates (AHRTA) is developing a type of hydropower
generator that uses oscillating wings to convert the flow energy of rivers and tidal streams into
electrical energy. AHRTA's concept manipulates an airfoil to oscillate in both plunge (pure
translation) and pitch (rotation about some axis on the airfoil chord line) to extract energy from
the air or water flow. The phase angle between the pitch and plunge oscillations must be close to
90 degrees. AHRTA has constructed an experimental model which enforces the plunge and pitch
oscillation with the proper phasing between the two motions, as shown in Figure 70. The model
has two wings arranged in a tandem configuration so that the two wings also operate with a 90-
degree phasing. Thus far, the model system has operated satisfactorily. AHRTA is now in the
process of developing a new model with a simpler mechanism to enforce the phasing between
the pitch and plunge motion.
Figure 70
AHRTA Oscillating Turbine Experimental Configuration
Free Flow Power
Free Flow Power (FFP) is developing a RISEC turbine system that uses a rim-mounted,
permanent magnet, direct-drive generator with front and rear diffusers and one moving part (the
rotor) to maximize efficiency. The generator uses a start-up bearing and a combination of
magnetic levitation and hydrodynamic bearings. At a flow of nine feet per second, the turbine
can produce 20kW of power.
Magnetic arrays, using rare earth Neodymium magnets, provide high field strength for greater
efficiency and lower harmonic content. This arrangement facilitates easier grid synchronization
than traditional bi-polar magnet arrays. Meanwhile, the generator's rotor is designed to operate
over a wider range of flow speeds (from two meters per second to five meters per second).
Figures 10-15 illustrate both the cross section and component parts that comprise the FFP turbine
generator, as well as an experimental rotor.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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FFP is designing a prototype turbine in collaboration with Springfield, N.J.-based Sigma Design
Co., Malta, N.Y.-based Advanced Energy Conversion, and Norwich, Vt.-based Turbo Solutions
Engineering. Looking ahead, the company plans to place six to 12 turbines in arrays on pilings,
25 feet off the bottom of a river and at least 40 feet below the surface to stay clear of ships and
boats.
Figure 71
FFP Turbine Generator
FFP expects to manufacture two versions of the Free Flow Turbine Generator:
• a two-meter version expected to generate 10kW in flows of 2 meters per second
• a one-meter version expected to generate 10kW in flows of 3 meters per second
Free Flow 69
Free Flow 69, founded in 2005, is researching a tidal power concept called "the sea engine,"
invented in 1988 but never developed. It has developed a vertical axis turbine, called the Osprey.
Although the design of the turbine is still confidential, the key advantages of the turbine include
1) its suitability for both river and tidal streams, 2) efficiency in variable heights of flow, 3)
relatively simple design and manufacture, and 5) easy maintenance (most of the complex
components are above water level).
Figure 72 shows the Osprey Prototype Turbine test rig, a 30-foot aluminum catamaran
manufactured by Able Engineering. Initial pilot trials are now being conducted.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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Figure 72 Free Flow 60 Osprey Turbine in Experimental Test Configuration
Hydro Green
Houston, TX-based Hydro Green Energy, LLC, has developed and patented a hydrokinetic
turbine array (HTA) system. The company intends to operate as an Independent Power Producer
(IPP), selling the power generated from its HTAs via long-term, wholesale power purchase
agreements (PPAs). Figure 73 illustrates a 2x2 hydrokinetic Hydropower Turbine Array
configuration. Figure 74 is an underwater view of the patented hydrokinetic in-stream river
current device array configuration.
93
Figure 73 Figure 74
Hydro Green Turbines Hydro Green Turbine Array Configuration
Lucid Energy Technologies
Formed in March of 2007, Lucid Energy Technologies is a joint venture between GCK
Technology, Inc., and Vigor Clean Tech, Inc. The company is focusing on designing and
commercializing complete hydrokinetic electricity generation systems based on the Gorlov
Helical Turbine (GHT). Figures 75 and 76, respectively, show a Lucid Energy turbine prototype
and an array configuration.
Figure 75 Figure 76
Lucid Energy Turbine Lucid Energy Array Configuration
System Level Design, Performance and Cost of Tacoma Narrows Tidal Power Plan
New Energy Corp.
New Energy Corporation is a Canada-based RISEC manufacturer of its proprietary EnCurrent
Turbines. The technology is based on the Darrieus wind turbine, also called an eggbeater or
whisk turbine due to its shape. The EnCurrent Turbine is a cross-flow turbine, meaning that the
direction of rotation is perpendicular to direction of water flow. When the turbine rotor is placed
within a water current, the hydrofoils generate a lift vector in the forward orientation which can
be captured at the shaft as a positive rotation. The hydrofoils experience their maximum forward
torque at the top and bottom of their rotation, when the water moving past them is tangential.
The turbine rotates in the same direction regardless of the direction of the water current and
captures between 35% and 40% of the energy in moving water. It rotates at a very low speed,
between 2 and 2.5 times the speed of the water in which it is submerged.
One of the unique properties of the Darrieus Turbine design is that it is able to capture the energy
from the water irrespective of the direction of the current. This property enables the EnCurrent
Turbine to harness the energy contained in both flood and ebb tides. A permanent magnet
generator is mounted on the turbine shaft to convert the torque generated by the rotor into
electricity. The output from the permanent magnet generator is a variable voltage AC signal
which is rectified to DC and fed into an inverter. The inverter takes the DC signal as input and
provides an AC output. Different inverters can be used to provide the appropriate power for the
regulatory requirements of any given area in the world.
New Energy currently manufactures 5kW, 10kW and 25kW models of the EnCurrent Power
Generation System; it is working to have 125kW and 250kW models available by Q4 of 2008.
New Energy also provides a set of ancillary products that support the installation of the
EnCurrent Power Generation System. A mount on a double hull pontoon boat is shown in
Figure 77 Figure 78
New Energy EnCurrent Turbine Illustration of a pontoon mount
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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Ocean Renewable Power Corp.
Ocean Renewable Power Company, LLC (ORPC), founded in 2004, has developed a proprietary
RISEC turbine named the ocean current generation (OCGen) Turbine Generating Unit (TGU).
The TGU turbine rotates in one direction only, regardless of current flow direction. Two cross
flow turbines drive a permanent magnet generator on a single shaft. TGUs are "stacked"
(horizontally or vertically) and incorporated into OCGen modules that contain the
ballast/buoyancy tanks and power electronics/control system (See Figure 79).
Assembled OCGen modules are deployed in arrays comprised of tens to hundreds of modules
and held into position underwater using deep sea mooring systems. A power and control cable
connects each OCGen module to an underwater transmission line that interconnects with an on-
shore substation. Generating capacity of up to 250kW is achievable in a six-knot current (varies
with current speed).
Figure 79
Ocean Renewable power Corp OCGenTM Module
In mid-May 2007, ORPC commenced an OCGen TGU demonstration project in tidal currents in
Western Passage (Passamaquoddy Bay) near Eastport, Maine. The demo, completed in early
2008, successfully proved the basic design and technical feasibility of the TGU. Data was also
collected for use in the subsequent TGU commercial designs.
The final and most critical test during the demonstration project was a seven-day continuous
deployment conducted while a barge with the TGU fully deployed was attached to stationary
moorings near Dog Island (Western Passage) (see Figure 80). The achieved results met or
exceeded expectations for all but two related performance parameters: ADCF Turbine Efficiency
and TGU Average and Peak Output.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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Figure 80
Testing of the Ocean Renewable power Corp OCGenTM Module in the Western Passage
UEK Corp.
UEK Corporation, founded in 1981, has developed the Underwater Electric Kite (UEK), a twin
horizontal axis turbine which features a unique, very high solidity (85%-95%) turbine design and
an augmenter ring (augments or increases the internal velocity of the water flow) in order to
create a system with high efficiency. Figure 81 shows a twin unit that tested for 36 days in May
2000 in the flume of the DeQew Hydroelectric Power Plant, owned and operated by Ontario
Hydro. Figure 82 illustrates a unit tested in the Chesapeake Bay. UEK is targeting project
opportunities at potential sites that can support underwater parks of twelve units or more.
Figure 81 Figure 82:
Twin UEK Turbine Installed at 17’ Single UEK tested in the Chesapeake Bay
Ontario Hydro
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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Verdant Power
New York, NY-based Verdant Power, founded in 2000, has built, tested and deployed four
working marine energy system prototypes. Dubbed the Free Flow, the system is comprised of
arrays of three-blade horizontal-axis turbines that resemble and operate similarly to present-day
wind turbines (see Figures 83 and 84). The turbine rotor is spun slowly and steadily (~32 rpm)
by the natural currents of tides and rivers. This motion drives a speed increaser, which in turn
drives a grid-connected generator, both of which are encased in a waterproof streamlined nacelle
mounted on a streamlined pylon.
Figure 83 Figure 84
Verdant Power Free Flow Verdant Power Turbine being lowered into the
Turbine East River prior to mounting with a monopile
Free Flow turbines can operate in both tidal and river settings. Turbines deployed in tidal
settings are assembled with internal yaw bearings, which allow the turbines to pivot with the
changing tide and capture energy for the majority of the day. Turbines deployed in rivers are
fixed and generate power on the continuous flow of the river throughout the day, providing
nearly 24-hour power. Depending on the site, various types of devices can be used to anchor the
turbines underwater.
Vortex Hydro
Founded in 2004, Vortex Hydro Energy LLC (VHE) is a Michigan-based company that has
developed a technology nicknamed VIVACE (Vortex Induced Vibrations Aquatic Clean
Energy). VIVACE uses vortex induced vibrations to extract energy from ocean, river, tidal and
other water currents. For decades, engineers have been trying to prevent Vortex Induced
Vibrations (VIV) from damaging offshore equipment and structures. VIVACE works by
maximizing and exploiting VIV rather than spoiling and preventing it.
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System Level Design, Performance and Cost – Alaska River In-Stream Power Plants
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As depicted in Figure 85, VIV results from vortices forming and shedding on the downstream
side of a bluff body in a current. Vortex shedding alternates from one side to the other, thereby
creating a vibration or oscillation. The VIV phenomenon is non-linear, which means it can
produce useful energy at high efficiency over a wide range of current speeds.
Figure 85
Vortex Induced Vibrations Oscillates Objects in Fluid Currents
VIVACE devices can be positioned beneath the surface, thereby avoiding interference with other
river uses, such as fishing, shipping and tourism. In addition, VIVACE utilizes vortex formation
and shedding, the same mechanism fish use to propel themselves through the water, to allow for
greater compatibility with marine life.
A VIVACE prototype is currently operating in the Marine Hydrodynamics Laboratory at the
University of Michigan. Testing is being funded by the U.S. DOE and the Office of Naval
Research.
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