HomeMy WebLinkAboutKetchikan Gatway Borough School District Fesability Assessment for High Efficiency Low Emmission Wood Heating Final AWEDTG 07-24-2012-BIO
Pre-Feasibility Assessment for
Integration of Wood-Fired Heating Systems
Final Report
July 24, 2012
Ketchikan Gateway Borough School District
Ketchikan High School
Ketchikan, Alaska
Presented by
CTA Architects Engineers
Nick Salmon & Nathan Ratz
Lars Construction Management Services
Rex Goolsby
For
Ketchikan Gateway Borough School
Ketchikan Indian Association
In partnership with
Fairbanks Economic Development Corporation
Alaska Wood Energy Development Task Group
Funded by
Alaska Energy Authority and U.S. Forest Service
306 W. Railroad, Suite 104
Missoula, MT 59802
406.728.9522
www.ctagroup.com
CTA Project: FEDC_KETCHCRAIG_KHS
Pre-Feasibility Assessment for Ketchikan High School
Integration of Wood-Fired Heating Systems Ketchikan, Alaska
CTA Architects Engineers i
July 24, 2012
TABLE OF CONTENTS
1.0 Executive Summary ................................................................................................... 1
2.0 Introduction ............................................................................................................... 3
3.0 Existing Building Systems.......................................................................................... 3
4.0 Energy Use ............................................................................................................... 3
5.0 Biomass Boiler Size ................................................................................................... 3
6.0 Wood Fuel Use .......................................................................................................... 4
7.0 Boiler Plant Location and Site Access ....................................................................... 5
8.0 Integration with Existing Heating Systems ................................................................. 5
9.0 Air Quality Permits ..................................................................................................... 5
10.0 Wood Heating Options .............................................................................................. 6
11.0 Estimated Costs ........................................................................................................ 6
12.0 Economic Analysis Assumptions ............................................................................... 6
13.0 Results of Evaluation ................................................................................................. 7
14.0 Project Funding ......................................................................................................... 7
15.0 Summary ................................................................................................................... 8
16.0 Recommended Action ............................................................................................... 8
Appendixes
Appendix A: Preliminary Estimates of Probable Cost .................................................. 1 page
Appendix B: Cash Flow Analysis ............................................................................... 2 pages
Appendix C: Site Plan ................................................................................................. 1 page
Appendix D: Air Quality Report ............................................................................... 11 pages
Appendix E: Wood Fired Heating Technologies ........................................................ 3 pages
Pre-Feasibility Assessment for Ketchikan High School
Integration of Wood-Fired Heating Systems Ketchikan, Alaska
CTA Architects Engineers Page 1 of 7
July 24, 2012
1.0 Executive Summary
The following assessment was commissioned to determine the preliminary technical and
economic feasibility of integrating a wood fired heating system at the Ketchikan High
School in Ketchikan, Alaska.
The following tables summarize the current fuel use and the potential wood fuel use:
Table 1.1 - Annual Fuel Use Summary
Fuel Avg. Use Current Annual
Facility Name Type (Gallons) Cost/Gal Cost
High School Fuel Oil 127,900 $3.70 $473,230
Table 1.2 - Annual Wood Fuel Use Summary
Chipped/
Fuel Wood Ground
Oil Pellets Wood
(Gallons) (Tons) (Tons)
High School 127,900 1049.3 1715.9
Note: Wood fuel use assumes offsetting 85% of the current energy use.
Due to the large volume of wood needed to heat the building, pellet and chipped/ground
fuel boilers were evaluated and cord wood systems were not considered. The options
reviewed were as follows:
Chipped/Ground Wood Boiler Options:
A.1: A freestanding boiler building with interior wood storage.
Wood Pellet Boiler Options:
B.1: A freestanding boiler building with adjacent free standing pellet silo.
The following table summarizes the economic evaluation for each option:
Table 1.3 - Economic Evaluation Summary
Ketchikan High School Biomass Heating System
Year 1 NPV NPV
20
Yr
30
Yr
Project Operating 30 yr 20 yr B/C B/C ACF ACF YR
Cost Savings at 3% at 3% Ratio Ratio YR 20 YR 30 ACF=PC
A.1 $1,793,000 $212,455 $10,179,110 $5,726,532 3.19 5.68 $8,187,188 $17,745,555 8
B.1 $1,400,000 $80,164 $6,373,815 $3,213,382 2.30 4.55 $4,694,187 $11,496,899 11
Ketchikan Gateway Borough School High School appears to be a good candidate for the
use of a wood biomass heating systems. With the current economic assumptions and the
current fuel use this wood chip boiler option has a very strong 20 year B/C ratio of 3.9, and
the wood pellet boiler a strong 20 year B/C ratio of 2.3.
Pre-Feasibility Assessment for Ketchikan High School
Integration of Wood-Fired Heating Systems Ketchikan, Alaska
CTA Architects Engineers Page 2 of 8
July 24, 2012
Because of the site constraints and air quality issues, the pellet boiler system would be
recommended over the chip system.
Pre-Feasibility Assessment for Ketchikan High School
Integration of Wood-Fired Heating Systems Ketchikan, Alaska
CTA Architects Engineers Page 3 of 8
July 24, 2012
2.0 Introduction
The following assessment was commissioned to determine the preliminary technical and
economic feasibility of integrating a wood fired heating system at the Ketchikan High
School in Ketchikan, Alaska.
3.0 Existing Building Systems
The Ketchikan High School is a steel and concrete framed building originally constructed
in 1953 and expanded and remodeled extensively in mid 1990’s. The facility is
approximately 110,000 square feet and is heated by one 3,770,000 Btu/hr output hot water
boiler and two 4,070,000 Btu/hr output hot water boilers. Domestic hot water is provided
by three 120 gallon indirect water heaters using the boiler water as a heating source.
These domestic water heaters then feed a single 1,500 gallon storage tank. The existing
boilers are original to the renovation work in the mid 1990’s and are in good condition.
Most of the heating system infrastructure was also updated in the mid 1990’s and is in
good condition.
Facilities Dropped from Feasibility Study
No facilities were dropped from the feasibility study.
Facilities Added to Feasibility Study
No facilities were added to the feasibility study.
4.0 Energy Use
Fuel oil bills for the facilities were provided. The following table summarizes the data:
Table 4.1 - Annual Fuel Use Summary
Fuel Avg. Use Current Annual
Facility Name Type (Gallons) Cost/Gal Cost
High School Fuel Oil 127,900 $3.70 $473,230
Electrical energy consumption will increase with the installation of the wood fired boiler
system because of the power needed for the biomass boiler components such as augers,
conveyors, draft fans, etc. and the additional pumps needed to integrate into the existing
heating systems. The cash flow analysis accounts for the additional electrical energy
consumption and reduces the annual savings accordingly.
5.0 Biomass Boiler Size
The following table summarized the connected load of fuel fired boilers:
Table 5.1 - Connected Boiler Load Summary
Likely
Peak System
Output Load Peak
MBH Factor MBH
Gateway Borough
School Boiler 1 Fuel Oil 3770 0.65 2451
Boiler 2 Fuel Oil 4070 0.65 2646
Boiler 3 Fuel Oil 4070 0.65 2646
Total 11910 7742
Pre-Feasibility Assessment for Ketchikan High School
Integration of Wood-Fired Heating Systems Ketchikan, Alaska
CTA Architects Engineers Page 4 of 8
July 24, 2012
Typically a wood heating system is sized to meet approximately 85% of the typical annual
heating energy use of the building. The existing heating boilers would be used for the
other 15% of the time during peak heating conditions, during times when the biomass
boiler is down for servicing, and during swing months when only a few hours of heating
each day are required. Recent energy models have found that a boiler sized at 50% to
60% of the building peak load will typically accommodate 85% of the boiler run hours.
Table 5.2 - Proposed Biomass Boiler Size
Likely Biomass
System Biomass Boiler
Peak Boiler Size
MBH Factor MBH
High School 7742 0.6 4645
6.0 Wood Fuel Use
The types of wood fuel available in the area include wood pellets and chipped/ground
wood fuel. The estimated amount of wood fuel needed for each wood fuel type for each
building was calculated and is listed below:
Table 6.1 - Annual Wood Fuel Use Summary
Chipped/
Fuel Wood Ground
Oil Pellets Wood
(Gallons) (Tons) (Tons)
High School 127,900 1049.3 1715.9
Note: Wood fuel use assumes offsetting 85% of the current energy use.
The amount of wood fuel shown in the table is for offsetting 85% of the total fuel oil use.
The moisture content of the wood fuels and the overall wood burning system efficiencies
were accounted for in these calculations. The existing fuel oil boilers were assumed to be
80% efficient. Wood pellets were assumed to be 7% MC with a system efficiency of 70%.
Chipped/ground fuel was assumed to be 40% MC with a system efficiency of 65%.
As can be seen from the potential wood fuel use, the volume of wood is such that a cord
wood system is not really practical and further analysis will look at pellet and
chipped/ground fuel options.
There are sawmills and active logging operations in the region. Tongass Forest
Enterprises has stared up a pellet plant in Ketchikan and is providing pellets to Sealaska.
Pellets are also available from plants in British Columbia, Washington, and Oregon. There
appears to be a sufficient available supply to service the boiler plant.
The unit fuel costs for fuel oil and the different fuel types were calculated and equalized to
dollars per million Btu ($/MMBtu) to allow for direct comparison. The Delivered $/MMBtu
is the cost of the fuel based on what is actually delivered to the heating system, which
includes all the inefficiencies of the different systems. The Gross $/MMBtu is the cost of
the fuel based on raw fuel, or the higher heating value and does not account for any
Pre-Feasibility Assessment for Ketchikan High School
Integration of Wood-Fired Heating Systems Ketchikan, Alaska
CTA Architects Engineers Page 5 of 8
July 24, 2012
system inefficiencies. The following table summarizes the equalized fuel costs at different
fuel unit costs:
Table 6.2 - Unit Fuel Costs Equalized to $/MMBtu
Net
Gross System System
Delivered Gross
Fuel Type Units Btu/unit Efficiency Btu/unit $/unit $/MMBtu $/MMBtu
Fuel Oil gal 138500 0.8 110800 $3.50 $31.59 $25.27
$4.00 $36.10 $28.88
$4.50 $40.61 $32.49
Pellets tons 16400000 0.7 11480000 $300.00 $26.13 $18.29
$350.00 $30.49 $21.34
$400.00 $34.84 $24.39
Chips tons 10800000 0.65 7020000 $75.00 $10.68 $6.94
$100.00 $14.25 $9.26
$125.00 $17.81 $11.57
7.0 Boiler Plant Location and Site Access
The boiler room is not large enough to accommodate a new wood fired boiler so a new
stand-alone plant would be required. The best location for a plant would be just northwest
of the boiler room, adjacent to the tennis courts to the north.
Any type of biomass boiler plant will require access by delivery vehicles, typically 40 foot
long vans or some similar type of trailer. The school is built on a steep site, limiting vehicle
access and space for constructing wood heating systems. A wood pellet boiler with
adjacent silos appear to the most appropriate solution. Wood pellet fuel would need to be
conveyed into the silo utilizing a pneumatic blower or grain auger. A pneumatic blower
allows greater flexibility in the relationship between the delivery vehicle and silo.
8.0 Integration with Existing Heating System
Integration of a wood fired boiler system would be relatively straight forward in the
building. The field visit confirmed the location of the boiler room in order to identify an
approximate point of connection from a biomass boiler to the existing building. Piping from
the biomass boiler plant would be run below ground with pre-insulated pipe and extended
to the face of each building, and extended up the exterior surface of the school in order to
penetrate exterior wall into the boiler room. Once the hot water supply and return piping
enters the existing boiler room it would be connected to existing supply and return pipes in
appropriate locations in order to utilize existing pumping systems within each building.
9.0 Air Quality Permits
Resource System Group has done a preliminary review of potential air quality issues in the
area. Southeast Alaska is has meteorological conditions that can create thermal
inversions, which are unfavorable for the dispersion of emissions. The proposed boiler
size at this location is small enough, that the boiler is not likely to require any State or
Federal permits. Since this plant will be located at a school and is also located in the
populated area, the air quality will likely be scrutinized and modeling of emissions, the
Pre-Feasibility Assessment for Ketchikan High School
Integration of Wood-Fired Heating Systems Ketchikan, Alaska
CTA Architects Engineers Page 6 of 8
July 24, 2012
stack height, and of air pollution control devices is recommended. RSG also recommends
pellet systems over chip systems for the ability of pellets to burn cleaner than chip
systems. See the air quality memo in Appendix D.
10.0 Wood Heating Options
The technologies available to produce heating energy from wood based biomass are
varied in their approach, but largely can be separated into three types of heating plants:
cord wood, wood pellet and wood chip/ground wood fueled. See Appendix E for these
summaries.
Due to the large volume of wood needed to heat the building, pellet and chipped/ground
fuel boilers were evaluated and cord wood systems were not considered. The options
reviewed were as follows:
Chipped/Ground Wood Boiler Options:
A.1: A freestanding boiler building with interior wood storage.
Wood Pellet Boiler Options:
B.1: A freestanding boiler building with adjacent free standing pellet silo.
11.0 Estimated Costs
The total project costs are at a preliminary design level and are based on RS Means and
recent biomass project bid data. The estimates are shown in the appendix. These costs
are conservative and if a deeper level feasibility analysis is undertaken and/or further
design occurs, the costs may be able to be reduced.
12.0 Economic Analysis Assumptions
The cash flow analysis assumes fuel oil at $3.70/gal, electricity at $0.10/kwh, wood pellets
delivered at $300/ton, and ground/chipped wood fuel delivered at $100/ton. The fuel oil
and electricity costs were based on utility bills. Pellet costs were obtained from Tongass
Forest Enterprises.
It is assumed that the wood boiler would supplant 85% of the estimated heating use, and
the existing heating systems would heat the remaining 15%. Each option assumes the
total project can be funded with grants and non obligated capital money. The following
inflation rates were used: O&M - 2%, Fossil Fuel – 5%, Wood Fuel – 3%, Discount Rate
for NPV calculation – 3%. The fossil fuel inflation rate is based on the DOE EIA website.
DOE is projecting a slight plateau with a long term inflation of approximately 5%. As a
point of comparison, oil prices have increased at an annual rate of over 8% since 2001.
The analysis also accounts for additional electrical energy required for the wood fired
boiler system as well as the system pumps to distribute heating hot water to the buildings.
Wood fired boiler systems also will require more maintenance, and these additional
maintenance costs are also factored into the analysis.
Pre-Feasibility Assessment for Ketchikan High School
Integration of Wood-Fired Heating Systems Ketchikan, Alaska
CTA Architects Engineers Page 7 of 8
July 24, 2012
13.0 Results of Evaluation
The following table summarizes the economic evaluation for each option:
Table 13.1 - Economic Evaluation Summary
Ketchikan High School Biomass Heating System
Year 1 NPV NPV
20
Yr
30
Yr
Project Operating 30 yr 20 yr B/C B/C ACF ACF YR
Cost Savings at 3% at 3% Ratio Ratio YR 20 YR 30 ACF=PC
A.1 $1,793,000 $212,455 $10,179,110 $5,726,532 3.19 5.68 $8,187,188 $17,745,555 8
B.1 $1,400,000 $80,164 $6,373,815 $3,213,382 2.30 4.55 $4,694,187 $11,496,899 11
The benefit to cost ratio (B/C) takes the net present value (NPV) of the net energy savings
and divides it by the construction cost of the project. A B/C ratio greater than or equal to
1.0 indicates an economically advantageous project.
Accumulated cash flow (ACF) is another evaluation measure that is calculated in this
report and is similar to simple payback with the exception that accumulated cash flow
takes the cost of financing and fuel escalation into account. For many building owners,
having the accumulated cash flow equal the project cost within 15 years is considered
necessary for implementation. If the accumulated cash flow equals project cost in 20
years or more, that indicates a challenged project. Positive accumulated cash flow should
also be considered an avoided cost as opposed to a pure savings.
Because this project involves as school, a life cycle cost analysis following the
requirements of the State of Alaska Department of Education & Early Development was
completed and the data is summarized in the following table:
Table 13.2 Life Cycle Costs of Project Alternatives
Alternate #1 Alternate #2
Existing
Boiler Wood Pellet Boiler
Initial Investment Cost $0 $1,400,000
Operations Cost $11,098,820 $6,160,797
Maintenance & Repair Cost $0 $56,725
Replacement Cost $0 $0
Residual Value $0 $0
Total Life Cycle Cost $11,098,820 $7,617,523
This life cycle cost analysis also indicates a pellet boiler system is a strong project.
14.0 Project Funding
The Ketchikan Gateway Borough School District may pursue a biomass project grant from
the Alaska Energy Authority.
Pre-Feasibility Assessment for Ketchikan High School
Integration of Wood-Fired Heating Systems Ketchikan, Alaska
CTA Architects Engineers Page 8 of 8
July 24, 2012
The Ketchikan Gateway Borough School District could also enter into a performance
contract for the project. Companies such as Siemens, McKinstry, Johnson Controls and
Chevron have expressed an interest in participating in funding projects of all sizes
throughout Alaska. This allows the facility owner to pay for the project entirely from the
guaranteed energy savings, and to minimize the project funds required to initiate the
project. The scope of the project may be expanded to include additional energy
conservation measures such as roof and wall insulation and upgrading mechanical
systems.
15.0 Summary
Ketchikan Gateway Borough School High School appears to be a good candidate for the
use of a wood biomass heating systems. With the current economic assumptions and the
current fuel use this wood chip boiler option has a very strong 20 year B/C ratio of 3.9, and
the wood pellet boiler a strong 20 year B/C ratio of 2.3.
Because of the site constraints and air quality issues, the pellet boiler system would be
recommended over the chip system.
Additional sensitivity analysis was performed on the wood pellet option. The cost of the
wood fuel was varied, and the 20 year B/C ratio exceeds 1.0 up to $385/ton.
16.0 Recommended Actions
Most grant programs will likely require a full feasibility assessment. A full assessment
would provide more detail on the air quality issues, wood fuel resources, and a schematic
design of the boiler systems and system integration to obtain more accurate costs.
It is recommended that the best location for a boiler plant be reviewed in more detail. A
boiler plant located further east than shown on the drawing may be avoid taking up parking
spots, but a portion of the tennis court may be lost to accommodate the plant. The route
and method of delivering pellets needs to be investigated further as this will affect the best
location for the boiler plant as well.
APPENDIX A
Preliminary Estimates of Probable Cost
Preliminary Estimates of Probable Cost
Ketchikan High School Biomass Heating Options
Ketchikan, AK
Option A.1 Wood Chip
Chip Storage/ Boiler Building:$270,000
Wood Heating & Wood Handling System: $325,000
Stack/Air Pollution Control Device: $180,000
Mechanical/Electrical within Boiler Building: $150,000
Underground Piping $25,000
KHS Integration $56,000
Subtotal:$1,006,000
30% Remote Factor $301,800
Subtotal:$1,307,800
Design Fees, Building Permit, Miscellaneous Expenses 15%: $196,170
Subtotal:$1,503,970
15% Contingency:$225,596
Total Project Costs 1,729,566$
Option B.1 Pellet
Chip Storage/ Boiler Building:$270,000
Wood Heating & Wood Handling System: $265,000
Stack/Air Pollution Control Device:$50,000
Mechanical/Electrical within Boiler Building: $150,000
Underground Piping $25,000
KHS Integration $56,000
Subtotal:$816,000
30% Remote Factor $244,800
Subtotal:$1,060,800
Design Fees, Building Permit, Miscellaneous Expenses 15%: $159,120
Subtotal:$1,219,920
15% Contingency:$182,988
Total Project Costs 1,402,908$
APPENDIX B
Cash Flow Analysis
Ketchikan High SchoolOption A.1Ketchikan, AKWood Chip Boiler Date: July 24, 2012 Analyst: CTA Architects Engineers - Nick Salmon & Nathan Ratz EXISTING CONDITIONSKHSTotalExisting Fuel Type:Fuel Oil Fuel Oil Fuel Oil Fuel OilFuel Units:gal gal gal galCurrent Fuel Unit Cost:$3.70 $3.60 $3.60 $3.60 Estimated Average Annual Fuel Usage:127,900127,900Annual Heating Costs:$473,230 $0 $0 $0 $473,230ENERGY CONVERSION (to 1,000,000 Btu; or 1 dkt)Fuel Heating Value (Btu/unit of fuel):138500 138500 138500 138500Current Annual Fuel Volume (Btu):17,714,150,000 0 0 0Assumed efficiency of existing heating system (%):80% 80% 80% 80% Net Annual Energy Produced (Btu):14,171,320,000 0 0 0 14,171,320,000WOOD FUEL COSTWood Chips$/ton: $100.00Assumed efficiency of wood heating system (%): 65% PROJECTED WOOD FUEL USAGEEstimated Btu content of wood fuel (Btu/lb) - Assumed 40% MC 5400 Tons of wood fuel to supplant net equivalent of 100% annual heating load.2,019Tons of wood fuel to supplant net equivalent of 85% annual heating load.1,71625 ton chip van loads to supplant net equivalent of 85% annual heating load.69 Project Capital Cost-$1,730,000 Project Financing InformationPercent Financed0.0%Est. Pwr Use 45000 kWh Type Hr/Wk Wk/Yr Total Hr Wage/Hr TotalAmount Financed$0 Elec Rate $0.280 /kWh Biomass System 4.0 40 160 $20.00 $3,200Amount of Grants$1,730,000 Other 0.0 40 0 $20.00 $01st 2 Year Learning 3.0 40 120 $20.00 $2,400Interest Rate5.00%Term10Annual Finance Cost (years)$0 8.1 years Net Benefit B/C Ratio$10,248,706 $8,518,706 5.92$5,796,128 $4,066,1283.35Year Accumulated Cash Flow > 0#N/AYear Accumulated Cash Flow > Project Capital Cost7Inflation FactorsO&M Inflation Rate2.0%Fossil Fuel Inflation Rate5.0%Wood Fuel Inflation Rate3.0%Electricity Inflation Rate3.0%Discount Rate for Net Present Value Calculation 3.0%Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year YearCash flow Descriptions Unit Costs HeatingSource ProportionAnnual Heating Source VolumesHeating Units 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 20 25 30Existing Heating System Operating CostsDisplaced heating costs $3.70 127900 gal $473,230 $496,892 $521,736 $547,823 $575,214 $603,975 $634,173 $665,882 $699,176 $734,135 $770,842$809,384 $849,853 $892,346 $936,963 $1,195,829 $1,526,214 $1,947,879Displaced heating costs $3.600 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Displaced heating costs $3.600 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Displaced heating costs $3.600 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Biomass System Operating CostsWood Fuel ($/ton, delivered to boiler site)$100.00 85% 1716 tons $171,590 $176,738 $182,040 $187,501 $193,126 $198,920 $204,888 $211,034 $217,365 $223,886 $230,603 $237,521 $244,646 $251,986 $259,545 $300,884 $348,807 $404,363Small load existing fuel$3.70 15% 19185 gal $70,985 $74,534 $78,260 $82,173 $86,282$90,596 $95,126 $99,882 $104,876 $110,120 $115,626 $121,408 $127,478 $133,852 $140,544 $179,374 $228,932 $292,182Small load existing fuel$3.60 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Small load existing fuel$3.60 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Small load existing fuel$3.60 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Additional Operation and Maintenance Costs$3,200 $3,264 $3,329 $3,396 $3,464 $3,533 $3,604 $3,676 $3,749 $3,824 $3,901 $3,979 $4,058 $4,140 $4,222 $4,662 $5,147$5,683Additional Operation and Maintenance Costs First 2 years$2,400 $2,448Additional Electrical Cost $0.280$12,600 $12,978 $13,367 $13,768 $14,181 $14,607 $15,045 $15,496 $15,961 $16,440 $16,933 $17,441 $17,965 $18,504 $19,059 $22,094 $25,613 $29,693Annual Operating Cost Savings$212,455$226,930$244,739$260,984$278,161$296,319$315,511$335,793$357,224$379,864$403,779$429,035$455,706$483,865$513,592$688,814$917,714$1,215,958Financed Project Costs - Principal and Interest0000000000 Displaced System Replacement Costs (year one only)0Net Annual Cash Flow212,455 226,930 244,739 260,984 278,161 296,319 315,511 335,793 357,224 379,864 403,779 429,035 455,706 483,865 513,592 688,814 917,714 1,215,958Accumulated Cash Flow212,455 439,385 684,125 945,109 1,223,269 1,519,588 1,835,099 2,170,893 2,528,117 2,907,981 3,311,760 3,740,795 4,196,501 4,680,366 5,193,958 8,268,776 ######### 17,827,143Additional Power UseAdditional MaintenanceSimple Payback: Total Project Cost/Year One Operating Cost Savings:Net Present Value (30 year analysis):Net Present Value (20 year analysis):
Ketchikan High SchoolOption B.1Ketchikan, AKWood Pellet Boiler Date: July 24, 2012 Analyst: CTA Architects Engineers - Nick Salmon & Nathan Ratz EXISTING CONDITIONSKHSTotalExisting Fuel Type:Fuel Oil Fuel Oil Fuel Oil Fuel OilFuel Units:gal gal gal galCurrent Fuel Unit Cost:$3.70 $3.70 $3.70 $3.70 Estimated Average Annual Fuel Usage:127,900127,900Annual Heating Costs:$473,230 $0 $0 $0 $473,230ENERGY CONVERSION (to 1,000,000 Btu; or 1 dkt)Fuel Heating Value (Btu/unit of fuel):138500 138500 138500 138500Current Annual Fuel Volume (Btu):17,714,150,000 0 0 0Assumed efficiency of existing heating system (%):80% 80% 80% 80% Net Annual Energy Produced (Btu):14,171,320,000 0 0 0 14,171,320,000WOOD FUEL COSTWood Pellets$/ton: $300.00Assumed efficiency of wood heating system (%): 70% PROJECTED WOOD FUEL USAGEEstimated Btu content of wood fuel (Btu/lb) - Assumed 7% MC 8200 Tons of wood fuel to supplant net equivalent of 100% annual heating load.1,234Tons of wood fuel to supplant net equivalent of 85% annual heating load.1,04925 ton chip van loads to supplant net equivalent of 85% annual heating load.42 Project Capital Cost-$1,400,000 Project Financing InformationPercent Financed0.0%Est. Pwr Use 25000 kWh Type Hr/Wk Wk/Yr Total Hr Wage/Hr TotalAmount Financed$0 Elec Rate $0.100 /kWh Biomass System 4.0 40 160 $20.00 $3,200Amount of Grants$1,400,000 Other 0.0 40 0 $20.00 $01st 2 Year Learning 2.0 40 80 $20.00 $1,600Interest Rate5.00%Term10Annual Finance Cost (years)$0 17.5 years Net Benefit B/C Ratio$6,373,815 $4,973,815 4.55$3,213,382 $1,813,3822.30Year Accumulated Cash Flow > 0#N/AYear Accumulated Cash Flow > Project Capital Cost11Inflation FactorsO&M Inflation Rate2.0%Fossil Fuel Inflation Rate5.0%Wood Fuel Inflation Rate3.0%Electricity Inflation Rate3.0%Discount Rate for Net Present Value Calculation 3.0%Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year Year YearCash flow Descriptions Unit Costs HeatingSource ProportionAnnual Heating Source VolumesHeating Units 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 20 25 30Existing Heating System Operating CostsDisplaced heating costs $3.70 127900 gal $473,230 $496,892 $521,736 $547,823 $575,214 $603,975 $634,173 $665,882 $699,176 $734,135 $770,842$809,384 $849,853 $892,346 $936,963 $1,195,829 $1,526,214 $1,947,879Displaced heating costs $3.700 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Displaced heating costs $3.700 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Displaced heating costs $3.700 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Biomass System Operating CostsWood Fuel ($/ton, delivered to boiler site)$300.00 85% 1049 tons $314,781 $324,224 $333,951 $343,970 $354,289 $364,918 $375,865 $387,141 $398,755 $410,718 $423,039 $435,731 $448,803 $462,267 $476,135 $551,970 $639,885 $741,802Small load existing fuel$3.70 15% 19185 gal $70,985 $74,534 $78,260 $82,173 $86,282$90,596 $95,126 $99,882 $104,876 $110,120 $115,626 $121,408 $127,478 $133,852 $140,544 $179,374 $228,932 $292,182Small load existing fuel$3.70 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Small load existing fuel$3.70 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Small load existing fuel$3.70 15% 0 gal $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0 $0Additional Operation and Maintenance Costs$3,200 $3,264 $3,329 $3,396 $3,464 $3,533 $3,604 $3,676 $3,749 $3,824 $3,901 $3,979 $4,058 $4,140 $4,222 $4,662 $5,147$5,683Additional Operation and Maintenance Costs First 2 years$1,600 $1,632Additional Electrical Cost $0.100$2,500 $2,575 $2,652 $2,732 $2,814 $2,898 $2,985 $3,075 $3,167 $3,262 $3,360 $3,461 $3,564 $3,671 $3,781 $4,384 $5,082$5,891Annual Operating Cost Savings$80,164$90,662$103,543$115,552$128,366$142,030$156,594$172,108$188,628$206,211$224,916$244,806$265,950$288,416$312,280$455,438$647,168$902,321Financed Project Costs - Principal and Interest0000000000 Displaced System Replacement Costs (year one only)0Net Annual Cash Flow80,164 90,662 103,543 115,552 128,366 142,030 156,594 172,108 188,628 206,211 224,916 244,806 265,950 288,416 312,280 455,438 647,168 902,321Accumulated Cash Flow80,164 170,827 274,370 389,922 518,287 660,317 816,910 989,019 1,177,647 1,383,858 1,608,773 1,853,580 2,119,529 2,407,946 2,720,226 4,694,187 7,524,448 11,496,899Additional Power UseAdditional MaintenanceSimple Payback: Total Project Cost/Year One Operating Cost Savings:Net Present Value (30 year analysis):Net Present Value (20 year analysis):
APPENDIX C
Site Plan
NEW BOILER BUILDINGNEW SILOSCHOOL94'-0"NORTHREF.LEGENDPIPE ROUTINGBOILER ROOM120'60'30'0SCALE: 1:60MISSOULA, MT(406)728-9522Fax (406)728-8287Date®BIOMASS PRE-FEASIBILITY ASSESSMENTKETCHIKAN, ALASKAKETCHIKAN HIGH SCHOOLSSFNHR07/24/12FEDCJ:ketchSCOLSITE PLAN
APPENDIX D
Air Quality Report
55 Railroad Row White River Junction, Vermont 05001
TEL 802.295.4999 FAX 802.295.1006 www.rsginc.com
INTRODUCTION
At your request, RSG has conducted an air quality feasibility study for seven biomass energy
installations in Ketchikan and Craig, Alaska. These sites are located in the panhandle of Alaska.
The following equipment is proposed:
Ketchikan
o One 4,700,000 Btu/hr (heat output) pellet boiler at the Ketchikan High School.
o One 800,000 Btu/hr (heat output) pellet boiler at the Ketchikan Indian Council
Medical Facility.
o One 150,000 Btu/hr (heat output) pellet boiler at the Ketchikan Indian Council
Votec School.
o One 200,000 Btu/hr (heat output) pellet boiler at the old Ketchikan Indian
Council Administration Building.
Craig
o One 450,000 Btu/hr (heat output) cord wood boiler at the Craig Tribal
Association Building.
o One 450,000 Btu/hr (heat output) cord wood boiler near the Fire Hall.
o One 250,000 Btu/hr (heat output) cord wood boiler at the Shaan‐Seet Office.
To: Nick Salmon
From: John Hinckley
Subject: Ketchikan‐Craig Cluster Feasibility Study
Date: 24 July 2012
Ketchikan‐Craig Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 2
A USGS map of the Ketchikan study area is provided in Figure 1 below. As shown, the area is
mountainous, with Ketchikan located on the southwest side of a mountain range. Ketchikan has
a population of 14,070. The area is relatively fairly well populated and developed relative to
other areas in Alaska. The area is also a port for cruise ships, which are significant sources of air
pollution. The topography, population, level of development, and existing emission sources has
the potential to create localized, temporary problematic air quality.
Figure 1: USGS Map Illustrating the Ketchikan Study Area
Ketchikan‐Craig Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 3
Figure 2 shows CTA Architects’ plan of the location of the proposed biomass facility at the
Ketchikan High School. The site slopes moderately to steeply downward in the southeasterly
direction with the grade becoming very steep to the northeast of the High School building. The
school building is between two to three stories high. The biomass facility will be located in a
stand‐alone building on the north side of the school building, which is the high side of the
building. There are residential areas west, north, and east of the proposed biomass facility
which are uphill (above) the facility. The precise dimensions of that building, the stack location
and dimensions, and the biomass equipment specifications have not been determined. The
degree of separation of the biomass building from the other buildings will create a buffer for
emissions dispersion.
Figure 2: Site Map of the Ketchikan High School Project
Ketchikan‐Craig Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 4
Figure 3 shows CTA Architects’ plan of the location of the proposed biomass facility at the
Ketchikan Indian Council Medical Facility. The site slopes moderately to steeply downward in
the southeasterly direction. As a result, there are buildings above and below the site. The
biomass facility will be located in a stand‐alone building on the northeast (uphill) side of the
school building. The precise dimensions of that building, the stack location and dimensions, and
the biomass equipment specifications have not been determined. The degree of separation of
the biomass building from the other buildings will create a small buffer for emissions
dispersion.
Figure 3: Site Map of the Ketchikan Indian Council Medical Facility
Ketchikan‐Craig Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 5
Figure 4 shows CTA Architects’ plan of the location of the Ketchikan Indian Council Votec School
(marked Stedman) and Ketchikan Indian Council Admin Building (marked Deermount). The
sites slope moderately to steeply downward in the southeasterly direction. As a result, there are
buildings above and below the sites. The precise dimensions of that building, the stack location
and dimensions, and the biomass equipment specifications have not been determined.
Figure 4: Site Map of Ketchikan Indian Council Votec School (Stedman) and the Admin
Building (Deermount)
Ketchikan‐Craig Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 6
A USGS map is provided below in Figure 5. As shown, Craig Island is relatively flat with
mountainous terrain to the west, and water in all other directions. The area is relatively
sparsely populated. The population of Craig is 1,397. Our review of the area did not reveal any
significant emission sources or ambient air quality issues.
Figure 5: USGS Map Illustrating the Craig Study Area
Ketchikan‐Craig Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 7
Figure 6 shows CTA Architects’ plan of the location of the proposed biomass facility and the
surrounding buildings. The site is relatively flat and moderately populated with one and two
story high buildings. The boiler plant is located in a stand‐alone building to the west of the
Tribal Association Building and east of another building. The stack should be designed to
provide plume rise above both of these buildings. The precise dimensions of that building, the
stack location and dimensions, and the biomass equipment specifications have not been
determined.
Figure 6: Site Map of the Craig Tribal Association Building
Ketchikan‐Craig Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 8
Figure 7 shows CTA Architects’ plan of the proposed Shaan‐Seet biomass facility and the
surrounding buildings. The site is relatively flat and moderately populated with one and two
story high buildings. The boiler plant is located in a stand‐alone building. The precise
dimensions of that building, the stack location and dimensions, and the biomass equipment
specifications have not been determined.
Figure 7: Site Map of Shaan‐Seet Boiler Plant Site
Ketchikan‐Craig Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 9
METEOROLOGY
Meteorological data from Annette, AK, was reviewed to develop an understanding of the
weather conditions. Annette is the closest weather data representing the climactic conditions
occurring in the Panhandle and is therefore a good proxy of Ketchikan and Craig weather
conditions. This data indicates calm winds occur only 10% of the year when, which suggests
there will be minimal time periods when thermal inversions and therefore poor emission
dispersion conditions can occur.1
Figure 8: Wind Speed Data from Annette, AK
1 See: http://climate.gi.alaska.edu/Climate/Wind/Speed/Annette/ANN.html
Ketchikan‐Craig Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 10
DESIGN & OPERATION RECOMMENDATIONS
The following are suggested for designing this project:
Burn natural wood, whose characteristics (moisture content, bark content, species,
geometry) results in optimal combustion in the equipment selected for the project.
Do not install a rain cap above the stack. Rain caps obstruct vertical airflow and reduce
dispersion of emissions.
Construct the stack to at least 1.5 times the height of the tallest roofline of the adjacent
building. Hence, a 20 foot roofline would result in a minimum 30 foot stack. Attention
should be given to constructing stacks higher than 1.5 times the tallest roofline
given higher elevations of surrounding residences due to the moderate to steep
slopes present.
Operate and maintain the boiler according to manufacturer’s recommendations.
Perform a tune‐up at least every other year as per manufacturer’s recommendations
and EPA guidance (see below for more discussion of EPA requirements)
Conduct regular observations of stack emissions. If emissions are not characteristic of
good boiler operation, make corrective actions.
For the Ketchikan High School: install at minimum a multicyclone to filter particulate
matter emissions.
These design and operation recommendations are based on the assumption that state‐of‐the‐
art combustion equipment is installed.
STATE AND FEDERAL PERMIT REQUIREMENTS
This project will not require an air pollution control permit from the Alaska Department of
Environmental Quality given the boilers’ relatively small size and corresponding quantity of
emissions. However, this project will be subject to new proposed requirements in the federal
“Area Source Rule” (40 CFR 63 JJJJJJ). A federal permit is not needed. However, there are various
record keeping, reporting and operation and maintenance requirements which must be
performed to demonstrate compliance with the requirements in the Area Source Rule. The
proposed changes have not been finalized. Until that time, the following requirements are
applicable:
Submit initial notification form to EPA within 120 days of startup.
Complete biennial tune ups per EPA method.
Submit tune‐up forms to EPA.
Please note the following:
Oil and coal fired boilers are also subject to this rule.
Ketchikan‐Craig Air Quality Feasibility Study Resource Systems Group, Inc.
24 July 2012 page 11
Gas fired boilers are not subject to this rule.
More requirements are applicable to boilers equal to or greater than 10 MMBtu/hr heat
input. These requirements typically warrant advanced emission controls, such as a
baghouse or an electrostatic precipitator (ESP).
The compliance guidance documents and compliance forms can be obtained on the following
EPA web page: http://www.epa.gov/boilercompliance/
SUMMARY
RSG has completed an air quality feasibility study for Ketchikan and Craig, Alaska. These boilers
are not subject to state permitting requirements, but are subject to federal requirements.
Design criteria have been suggested to minimize emissions and maximize dispersion.
The following conditions suggest advanced emission control devices (ESP, baghouse) are not
mandatory in Ketchikan and Craig:
1. The wood boilers will be relatively small emission sources.
2. Most of the wood boilers will be located in a separate building which will create a
dispersion buffer between the boiler stack and the building.
3. There are no applicable federal or state emission limits.
4. Meteorological conditions are favorable for dispersion.
The following conditions suggest additional attention should be given to controlling emissions
in Ketchikan:
1. Presence of other emission sources.
2. Relatively high population density.
3. The sensitive populations housed by all Ketchikan buildings.
While not mandatory, we recommend exploring the possibility of a cyclone or multi‐cyclone
technology for control of fly ash and larger particulate emissions for all the aforementioned
boilers. We also recommend developing a compliance plan for the aforementioned federal
requirements.
Given its size and sensitive population served, air dispersion modeling can be performed for the
Ketchikan High School site to determine the stack height and degree of emission control
(multicyclone vs ESP).
Please contact me if you have any comments or questions.
APPENDIX E
Wood Fired Heating Technologies
WOOD FIRED HEATING TECHNOLOGIES
CTA has developed wood-fired heating system projects using cord wood, wood pellet
and wood chips as the primary feedstock. A summary of each system type with the
benefits and disadvantages is noted below.
Cord Wood
Cord wood systems are hand-stoked wood boilers with a limited heat output of 150,000-
200,000 British Thermal Units per hour (Btu/hour). Cord wood systems are typically
linked to a thermal storage tank in order to optimize the efficiency of the system and
reduce the frequency of stoking. Cord wood boiler systems are also typically linked to
existing heat distribution systems via a heat exchanger. Product data from Garn, HS
Tarm and KOB identify outputs of 150,000-196,000 Btu/hr based upon burning eastern
hardwoods and stoking the boiler on an hourly basis. The cost and practicality of stoking
a wood boiler on an hourly basis has led most operators of cord wood systems to
integrate an adjacent thermal storage tank, acting similar to a battery, storing heat for
later use. The thermal storage tank allows the wood boiler to be stoked to a high fire
mode 3 times per day while storing heat for distribution between stoking. Cord wood
boilers require each piece of wood to be hand fed into the firebox, hand raking of the
grates and hand removal of ash. Ash is typically cooled in a barrel before being stock
piled and later broadcast as fertilizer.
Cordwood boilers are manufactured by a number of European manufacturers and an
American manufacturer with low emissions. These manufacturers currently do not
fabricate equipment with ASME (American Society of Mechanical Engineers)
certifications. When these non ASME boilers are installed in the United States,
atmospheric boilers rather than pressurized boilers are utilized. Atmospheric boilers
require more frequent maintenance of the boiler chemicals.
Emissions from cord wood systems are typically as follows:
PM2.5 >0.08 lb/MMbtu
NOx 0.23 lb/MMbtu
SO2 0.025 lb/MMbtu
CO2 195 lb/MMbtu
Benefits:
Small size
Lower cost
Local wood resource
Simple to operate
Disadvantages:
Hand fed - a large labor commitment
Typically atmospheric boilers (not ASME rated)
Thermal Storage is required
Page 1
Wood Pellet
Wood pellet systems can be hand fed from 40 pound bags, hand shoveled from 2,500
pound sacks of wood pellets, or automatically fed from an adjacent agricultural silo with
a capacity of 30-40 tons. Pellet boilers systems are typically linked to existing heat
distribution systems via a heat exchanger. Product data from KOB, Forest Energy and
Solagen identify outputs of 200,000-5,000,000 Btu/hr based upon burning pellets made
from waste products from the western timber industry. A number of pellet fuel
manufacturers produce all tree pellets utilizing bark and needles. All tree pellets have
significantly higher ash content, resulting in more frequent ash removal. Wood pellet
boilers typically require hand raking of the grates and hand removal of ash 2-3 times a
week. Automatic ash removal can be integrated into pellet boiler systems. Ash is
typically cooled in a barrel before being stock piled and later broadcast as fertilizer.
Pellet storage is very economical. Agricultural bin storage exterior to the building is
inexpensive and quick to install. Material conveyance is also borrowed from agricultural
technology. Flexible conveyors allow the storage to be located 20 feet or more from the
boiler with a single auger.
Emissions from wood pellet systems are typically as follows:
PM2.5 >0.09 lb/MMbtu
NOx 0.22 lb/MMbtu
SO2 0.025 lb/MMbtu
CO2 220 lb/MMbtu
Benefits:
Smaller size (relative to a chip system)
Consistent fuel and easy economical storage of fuel
Automated
Disadvantages:
Higher system cost
Higher cost wood fuel ($/MMBtu)
Page 2
Page 3
Wood Chip
Chip systems utilize wood fuel that is either chipped or ground into a consistent size of
2-4 inches long and 1-2 inches wide. Chipped and ground material includes fine
sawdust and other debris. The quality of the fuel varies based upon how the wood is
processed between the forest and the facility. Trees which are harvested in a manner
that minimizes contact with the ground and run through a chipper or grinder directly into
a clean chip van are less likely to be contaminated with rocks, dirt and other debris. The
quality of the wood fuel will also be impacted by the types of screens placed on the
chipper or grinder. Fuel can be screened to reduce the quantity of fines which typically
become airborne during combustion and represent lost heat and increased particulate
emissions.
Chipped fuel is fed from the chip van into a metering bin, or loaded into a bunker with a
capacity of 60 tons or more. Wood chip boilers systems are typically linked to existing
heat distribution systems via a heat exchanger. Product data from Hurst, Messersmith
and Biomass Combustion Systems identify outputs of 1,000,000 - 50,000,000 Btu/hr
based upon burning western wood fuels. Wood chip boilers typically require hand raking
of the grates and hand removal of ash daily. Automatic ash removal can be integrated
into wood chip boiler systems. Ash is typically cooled in a barrel before being stock piled
and later broadcast as fertilizer.
Emissions from wood chip systems are typically as follows:
PM2.5 0.21 lb/MMbtu
NOx 0.22 lb/MMbtu
SO2 0.025 lb/MMbtu
CO2 195 lb/MMbtu
Benefits:
Lowest fuel cost of three options ($/MMBtu)
Automated
Can use local wood resources
Disadvantages:
Highest initial cost of three types
Larger fuel storage required
Less consistent fuel can cause operational and performance issues