HomeMy WebLinkAboutCordova Feasibility Assessment for Biomass Heating Systems Swimming Pool Bob Korn CoffmanEngineers 07-29-2015-BIO
Feasibility Assessment for Biomass Heating Systems
Bob Korn Memorial Swimming Pool, Cordova, Alaska
800 F Street, Anchorage, AK 99501
p (907) 276-6664 f (907) 276-5042
Lee Bolling, PE
FINAL REPORT – 7/29/2015
Feasibility Assessment for Biomass Heating Systems Cordova, AK
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Contents
I. Executive Summary ............................................................................................................ 1
II. Introduction ...................................................................................................................... 2
III. Preliminary Site Investigation ........................................................................................... 3
PREVIOUS STUDIES ......................................................................................................................................................... 3
BUILDING DESCRIPTION ................................................................................................................................................... 3
EXISTING HEATING SYSTEM .............................................................................................................................................. 3
POOL WATER ................................................................................................................................................................ 4
DOMESTIC HOT WATER................................................................................................................................................... 4
AIR HANDLING SYSTEM ................................................................................................................................................... 4
BUILDING ENVELOPE ....................................................................................................................................................... 5
HYDRO ELECTRIC BOILER PROJECT ..................................................................................................................................... 5
AVAILABLE SPACE ........................................................................................................................................................... 6
STREET ACCESS AND FUEL STORAGE ................................................................................................................................... 6
BUILDING OR SITE CONSTRAINTS ....................................................................................................................................... 7
BIOMASS SYSTEM INTEGRATION ........................................................................................................................................ 7
BIOMASS SYSTEM OPTIONS .............................................................................................................................................. 7
IV. Energy Consumption and Costs ......................................................................................... 9
ENERGY COSTS .............................................................................................................................................................. 9
WOOD ENERGY ............................................................................................................................................................. 9
CORDWOOD .................................................................................................................................................................. 9
CARDBOARD BRIQUETTES .............................................................................................................................................. 10
WOOD PELLETS ........................................................................................................................................................... 11
HEATING OIL ............................................................................................................................................................... 12
ELECTRICITY ................................................................................................................................................................ 12
EXISTING FUEL OIL CONSUMPTION .................................................................................................................................. 13
BIOMASS SYSTEM CONSUMPTION ................................................................................................................................... 13
V. Preliminary Cost Estimating ............................................................................................. 14
VI. Economic Analysis .......................................................................................................... 15
O&M COSTS .............................................................................................................................................................. 15
DEFINITIONS................................................................................................................................................................ 15
RESULTS ..................................................................................................................................................................... 17
SENSITIVITY ANALYSIS ................................................................................................................................................... 18
VII. Forest Resource and Fuel Availability Assessments ........................................................ 19
FOREST RESOURCE ASSESSMENTS .................................................................................................................................... 19
AIR QUALITY PERMITTING .............................................................................................................................................. 19
VIII. General Biomass Technology Information ..................................................................... 20
HEATING WITH WOOD FUEL ........................................................................................................................................... 20
TYPES OF WOOD FUEL .................................................................................................................................................. 20
HIGH EFFICIENCY WOOD PELLET BOILERS ......................................................................................................................... 21
HIGH EFFICIENCY CORDWOOD BOILERS ............................................................................................................................ 21
LOW EFFICIENCY CORDWOOD BOILERS ............................................................................................................................. 22
HIGH EFFICIENCY WOOD STOVES .................................................................................................................................... 22
BULK FUEL BOILERS ...................................................................................................................................................... 22
Feasibility Assessment for Biomass Heating Systems Cordova, AK
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GRANTS ..................................................................................................................................................................... 22
Appendices
Appendix A – Site Photos
Appendix B – Economic Analysis Spreadsheet
Appendix C – AWEDTG Field Data Sheet
Feasibility Assessment for Biomass Heating Systems Cordova, AK
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Abbreviations
ACF Accumulated Cash Flow
ASHRAE American Society of Heating, Refrigeration, and Air-Conditioning Engineers
AEA Alaska Energy Authority
AFUE Annual Fuel Utilization Efficiency
B/C Benefit / Cost Ratio
BTU British Thermal Unit
BTUH BTU per hour
CCF One Hundred Cubic Feet
CEI Coffman Engineers, Inc.
CFM Cubic Feet per Minute
Eff Efficiency
F Fahrenheit
ft Feet
GPM Gallons Per Minute
HP Horsepower
HVAC Heating, Ventilating, and Air-Conditioning
in Inch(es)
kWh Kilowatt-Hour
lb(s) Pound(s)
MBH Thousand BTUs per Hour
O&M Operations and Maintenance
MMBTU One Million BTUs
PC Project Cost
R R-Value
SF Square Feet, Supply Fan
TEMP Temperature
V Volts
W Watts
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List of Figures
Figure 1 – Cordova, Alaska – Google Maps ................................................................................................... 2
Figure 2 – Bob Korn Memorial Swimming Pool ............................................................................................ 2
Figure 3 – Proposed Site Layout ................................................................................................................... 6
Figure 4 – Garn WHS-3200 Wood Boiler ....................................................................................................... 7
Figure 5 – Cardboard Shredder and Briquette Press .................................................................................. 10
List of Tables
Table 1 – Economic Evaluation Summary ..................................................................................................... 1
Table 2 – List of Previous Biomass Related Studies ...................................................................................... 3
Table 3 – Energy Comparison ....................................................................................................................... 9
Table 4 – Energy Comparison ..................................................................................................................... 11
Table 5 – Existing Fuel Oil Consumption ..................................................................................................... 13
Table 6 – Proposed Biomass System Fuel Consumption ............................................................................ 13
Table 7 – Estimate of Probable Cost ........................................................................................................... 14
Table 8 – Inflation rates .............................................................................................................................. 15
Table 9 – Economic Definitions ................................................................................................................... 15
Table 10 – Economic Analysis Results ......................................................................................................... 17
Table 11 – Sensitivity Analysis .................................................................................................................... 18
Feasibility Assessment for Biomass Heating Systems Cordova, AK
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I. Executive Summary
A preliminary feasibility assessment was completed to determine the technical and economic viability of
biomass heating systems at the Bob Korn Memorial Swimming Pool in Cordova, Alaska. The study
evaluated a Garn style cordwood boiler system that would supply the majority of the pool water heating
requirements. The high price of fuel oil is the main economic driver for the use of lower cost biomass
heating.
During the site visit it was found that a significant amount of energy was being lost through the pool’s
exhaust fans, which are used to control the humidity in the pool. It is recommended that a new pool
dehumidification system be investigated to control humidity, which is estimated to save $20,000 per
year in heating oil consumption. This improvement is recommended to be completed prior to
consideration of heating oil reductions based solely on a biomass heating system installation. It is
recommended to complete an economic analysis of a new pool dehumidification system. It is possible
that this system could have a greater benefit to cost ratio and quicker payback than a biomass heating
system.
The proposed wood boiler would be located in a detached conex and heating pipes would connect to a
new heat exchanger in the Pool’s mechanical room. The wood boiler would be dedicated to heating the
pool water, in order to take advantage of lower heating water temperatures and overall higher wood
boiler efficiencies. The existing heating oil boiler would still be used to heat the rest of the facility and
supplement the pool water heating when needed. The wood boiler would also allow for the burning of
cardboard briquettes.
The proposed wood boiler is economically justified at this time, due to the fact that the benefit to cost
ratio of the project is greater than 1.0. The summary of the results of the economic evaluation are shown
in the table below.
Table 1 – Economic Evaluation Summary
Project Capital Cost $330,734
Present Value of Project Benefits (20 year life) $2,063,893
Present Value of Operating Costs (20 year life) $1,337,273
Benefit / Cost Ratio of Project (20 year life) 2.20
Net Present Value (20 year life) $395,886
Year Accumulated Cash Flow is Net Positive First Year
Year Accumulated Cash Flow > Project Capital Cost 11 years
Simple Payback 13.1 years
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II. Introduction
A preliminary feasibility assessment was completed to determine the technical and economic viability of
biomass heating systems for the Bob Korn Memorial Swimming Pool in Cordova, Alaska. The location of
the building is shown in Figures 1 and 2. The pool is located next to the harbor and the city office building.
Figure 1 – Cordova, Alaska – Google Maps
Figure 2 – Bob Korn Memorial Swimming Pool
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III. Preliminary Site Investigation
Previous Studies
There have been multiple biomass related studies completed for Cordova, beginning in 2008. These
studies have looked at biomass resources, biomass prices and economics. These past studies were used
in developing this report and are listed below:
Table 2 – List of Previous Biomass Related Studies
Date Report Title Author
2008 Waste Audit of Burn Pile City of Cordova
Environmental Interns
2009 Native Village of Eyak
Feasibility Assessment for Biomass Heating Dalson Energy
2012 Assessment of Woody Biomass Energy Resources
in the Cordova Area
Department of Natural
Resources Division of
Forestry
2013 Cordova Biomass Feasibility Study Native Village of Eyak
In general, the studies found that cordwood is a potentially viable energy resource in Cordova. However,
during the writing of the 2009 report it was found that the cardboard and wood waste streams were not
large enough to justify burning these fuels to heat downtown buildings in Cordova.
Building Description
The pool is a 4,000 square foot single story building that was originally built in 1973. In 1983 there was a
major mechanical system renovation that installed new equipment and duct. The pool is used daily for
swimming activities by the community. Depending on the time of day and activity, there can be between
5 to 75 people using the pool. It is estimated that the pool is regularly used 70 hours per week. Currently,
there are no scheduled or planned renovations for the building. A city wide energy audit was completed
on Cordova City buildings, including the pool, in 2014. This energy audit only looked at energy data of the
city buildings and did not include a detailed energy audit of the pool building. The only information from
this energy audit that was provided to Coffman was the 2013 and 2014 heating oil and electricity energy
consumption and costs for the pool.
Existing Heating System
The pool is heated by one Viessmann Vitotrond 200 oil boiler (Model: VD2-780, 3,059 MBH Input, 2,693
MBH Output) that was installed in 2007. The boiler delivers heated glycol to various heating loads
throughout the building, including:
heating coils in two air handling units,
a small area of perimeter baseboard,
a shell and tube heat exchanger for heating the pool water, and
indirect hot water heaters for heating domestic hot water.
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The boiler, heat exchanger and pumps are located in the boiler room, which has two exterior walls. The
boiler system runs in a primary/secondary system, which utilizes several system pumps to transfer heated
glycol to different zones. The combustion efficiency of the existing fuel oil boiler is approximately 88%.
For this study, the Annual Fuel Utilization Efficiency of the oil boiler system was estimated at 80% to
account for typical oil boiler inefficiencies, including short cycling.
There is routine maintenance of the boiler by the City of Cordova maintenance employee (Micah
Renfeldt). The boiler appears to be in good shape and operating correctly. However, it was reported to
Coffman that it is difficult to find parts for the boiler because the manufacturer is based in Germany. It
was also reported that the boiler is difficult to work on and troubleshoot due to its complexity, as
compared to more common boilers found in the United States.
One 1,000 gal heating oil tank serves the boiler and is located on the north side of the building. The tank
is dual wall and made by Greer. There is no additional spill containment present around the tank. Fuel
oil in the tanks is only used for building heating, pool water heating and domestic hot water, and is not
used by other buildings.
Pool Water
According to the design drawings, the pool water capacity is approximately 134,000 gallons of water and
requires 600,000 BTU/hr to raise the water temp 0.5 degrees Fahrenheit per hour. A Shell and Tube heat
exchanger is used to heat the pool water with a loop from the boiler. The pool utilizes a pool cover during
unoccupied times to reduce the humidity load in the building. Using a pool cover is an important energy
efficiency strategy and it is recommended that it continues to be used.
Domestic Hot Water
Domestic hot water is used for showers, hand washing and laundry. Hot water is provided by three
Viessmann Vitocell (Model H-300) indirect hot water heaters that each have 120 gallon capacity. A boiler
loop is used to indirectly heat the hot water.
Air Handling System
The pool uses two air handling units (AHUs) to supply heated fresh air to the building. AHU-1 serves the
pool area and AHU-2 serves the office and locker room spaces. Three large exhaust fans are used to
ventilate the pool area to control the humidity levels. A significant amount of energy is being lost through
the pool’s exhaust fans. It was also reported that the exhaust fans typically run continually. Using exhaust
fans to control humidity leads to a significant amount of wasted energy. It is recommended that a new
pool dehumidification system be investigated to control humidity. Preliminary calculations show that
an estimated $20,000 per year in heating oil could be saved by adding a dehumidification system. This
improvement is recommended to be completed prior to further evaluation of a biomass heating system.
During the site visit it was found that several of the pumps and fans were in manual override mode and
are operating continuously. There appears to be significant energy savings in re-commissioning the
existing ventilation system to optimize performance and adding an energy recovery system to the exhaust
fans. It is recommended that the ventilation system be re-commissioned and energy recovery
investigated. This can significantly increase the energy efficiency of the building and reduce heating oil
(or cordwood) consumption.
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Building Envelope
The building is primarily concrete block construction with no additional wall insulation. The mechanical
room is 2x4 wood stud construction. The roof is a built up hot roof with an unknown amount of insulation.
The design drawings of the facility do not call out insulation or insulation values for the roof or walls of
the building. There are no windows in the building. There is an arctic entry way at the main entrance and
two man doors at the boiler room.
Hydro Electric Boiler Project
During the site visit Coffman met with Marc Mueller-Stoffels, Ph.D. from the Alaska Center for Energy and
Power (ACEP), who is currently investigating a project with the Cordova Electric Cooperative (CEC). ACEP
is studying how an electric resistance boiler at the pool could use excess hydro power during the summer
months to offset heating oil. CEC would sell the excess hydro power at a reduced rate and the electric
boiler would produce heat, which could offset a significant amount of heating oil.
There are opportunities to combine both electric heating and a biomass boiler system. For example, the
Garn boiler system may be able to be installed with an electric heating element. This would allow the
Garn boiler to act as an electric boiler when cheap hydro power is available in the summer. When excess
hydro power is not available (in the fall or winter), then the Garn boiler could be fired with cordwood to
offset heating oil consumption. The Garn also has a large water jacket (The WHS-3200 has 3,200 gallons
of water) that can act as a buffer tank for utilizing the electric heating elements.
If CEC can sell excess hydro power at a low enough rate, the electric boiler would be a great project to
pursue. It is recommended that this project be investigated further. Additional equipment cost savings
could be had by incorporating the electric boiler into a biomass boiler system as described above.
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Available Space
There is no space inside of the pool building for a biomass system, so a new detached building will be
needed to house a biomass boiler system. There is limited space around the pool building for a new
biomass building. The pool is butted up against a steep hill and rock face, which makes access to the rear
and side of the building quite difficult. The front of the pool faces the street, which does not have
adequate space. The only remaining area that can be easily accessed is the north side of the pool, where
the heating oil tank is located. This area faces the New City office building which is currently under
construction.
Figure 3 – Proposed Site Layout
A new biomass building could be built on the north side of the pool as shown in the figure above.
However, the location of the building will need to be coordinated with the new stairwell that is planned
to be installed adjacent to the new City Office building. See the photo above for the approximate location
of the proposed biomass building and future stairwell.
Street Access and Fuel Storage
The building site is situated along a paved road that can be easily accessed. A small amount of cordwood
could be stored near the proposed biomass building, however space is limited. Another option is to
possibly combine wood storage under the future stairwell. A third option is to store wood at the base of
the new City Office building approximately 50 feet north of the proposed biomass building. This is a larger
area that could be easily accessed for wood storage.
Location of Proposed
Biomass Building
Approximate location
of future stairwell
New City Office Building
under construction
Pool
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Building or Site constraints
The site is slightly sloping and has no wetlands or signs of historical structures. The primary constraint to
the site is the available space.
Biomass System Integration
The pool’s existing hydronic system is designed to operate at high temperatures (200 F supply water
temperature and a 180 F return water temperature), which makes it difficult to tie in a Garn style biomass
boiler that operates at lower supply water temperatures (around 140 F). The most cost effective way to
integrate the Garn boiler is to dedicate the Garn boiler to heating pool water only. A new heat exchanger
specifically designed for heating pool water integrated with the Garn would be installed. The rest of the
facility would be heated with the existing hydronic system and oil boiler. The existing tube and shell heat
exchanger for heating the pool water with the oil boiler would be kept for auxiliary heating.
The existing heating oil boiler utilizes a fully modulating RL70/M Riello burner, which allows the boiler to
turn down its heat output to one-third. Because of this feature the boiler system does not appear so
oversized that there will be major operational issues. However, it may be advantageous to investigate
adding a smaller oil boiler, electric boiler, or heat pump for heating the rest of the facility (non-pool water
heating), to reduce potential short cycling of the existing oil boiler. The design of the new hydronic system
should find ways to minimize potential short cycling of the existing oil boiler. Further engineering design
will be required to determine specific strategies for reducing boiler short cycling. Adding a smaller
auxiliary heat source as mentioned above is not included as part of this economic analysis.
Biomass System Options
The City of Cordova is very interested in burning cardboard briquettes. Cordova also has access to local
cordwood resources and does not have local access to wood pellets or wood chips. Due to these factors
the best biomass technology will be a Garn boiler type system. This will allow burning of both cordwood
and cardboard briquettes in a single boiler.
Figure 4 – Garn WHS-3200 Wood Boiler
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For this study, a single Garn WHS-3200 wood boiler was studied. This unit has a 3,200 gallon water tank
and is 7’4” wide x 7’8” high x 12’ long. The Garn boiler would be housed in an 8’ wide x 20’ long insulated
conex located on the north side of the pool. The conex would contain a circulation pump, heat exchanger
and controls. The conex and interior components could be pre-constructed offsite and shipped to
Cordova for installation.
The Garn boiler would deliver heat to a heat exchanger inside the conex, which would transfer heat to a
buried piping loop system with 50% propylene glycol. This loop would deliver heat through a direct buried,
insulated arctic pipe to a new heat exchanger in the pool’s boiler room, which would be used to heat the
pool water.
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IV. Energy Consumption and Costs
Energy Costs
The table below shows the energy comparison of different fuel types. The system efficiency is used to
calculate the delivered MMBTU’s of energy to the building. The delivered cost of energy to the building,
in $/MMBTU, is the most accurate way to compare costs of different energy types. As shown below,
cordwood is cheaper than fuel oil on a $/MMBTU basis in the Cordova area.
Table 3 – Energy Comparison
Fuel Type Units Gross
BTU/unit
System
Efficiency $/unit Delivered
$/MMBTU
Cordwood cord 14,990,000 75% $225 $20.01
Cardboard Briquettes ton 14,000,000 75% $210 to $392 1 $20.01 to $37.31
Fuel Oil gal 134,000 80% $4.00 $37.31
Electricity kWh 3,413 99% $0.20 2 $59.19
Wood Pellets
(Shipped to Cordova)
ton 16,000,000 85% $839 $61.69
1 The price of cardboard briquettes unknown at this time. The price range shown is for reference to see
the equivalent cost of cordwood and heating oil on an energy basis.
2 The electricity rate is not a reduced rate when excess hydro is available.
Wood Energy
The gross energy content of a cord of wood varies depending on tree species and moisture content. Wet
or greenwood has higher moisture contents and require additional heat to evaporate moisture before the
wood can burn. Thus, wood with higher moisture contents will have lower energy contents. Seasoned
or dry wood will typically have 20% moisture content. According to the 2013 Cordova Biomass Feasibility
Study, Cordova has access to hemlock, Sitka spruce and black cottonwood. The 2013 study estimates that
the average heating value of these three sources is 14.99 MMBTU/cord, which was used for the
calculations in Coffman’s analysis. To determine the delivered $/MMBTU of the biomass system, a 75%
efficiency for batch burning systems was assumed. This is based on Garn manufacturer documentation
and typical operational issues which do not allow firing 100% of the time.
According to Keith Kelley with Garn Wood Heating Systems, the Garn boilers are fully capable of burning
waste wood products such as wood pallets, wood flooring, and wood straps. However, any wood products
with glues, paints or finishes (such as plywood or painted wood) should not be burned due to the toxins
released in the combustion gases.
Cordwood
At this time there is no commercial distributer of cordwood in Cordova. However, this may be an
economic opportunity for a business in the future. The 2013 Cordova Biomass Feasibility Study estimates
that cordwood can be purchased at a price of $225/cord. This cost is used for Coffman’s economic
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analysis. Please refer to the 2013 study for an in depth analysis of the cordwood resource and pricing.
The study shows that there is adequate cordwood resources in the Cordova area.
Cardboard Briquettes
Cardboard briquettes is another biomass resource that can be utilized. Cordova’s cardboard resource has
been studied multiple times in 2009 Dalson Energy Study and the 2013 Cordova Biomass Feasibility Study.
These studies estimate the heating value of cardboard from 6,000 BTU/lb to 7,939 BTU/lb. For Coffman’s
analysis, a heating value of 7,000 BTU/lb (14.0 MMBTU/ton) for cardboard was used. Cardboard
briquettes can be batch burned similar to cordwood in a Garn system. So the same Garn unit could burn
both cordwood and cardboard briquettes. Like cordwood above, an efficiency of 75% for burning
cardboard briquettes is used for the study.
The amount of cardboard generated in Cordova has increased over the years. The 2009 Dalson Energy
Study estimated 10 to 16 tons of annual cardboard. In the spring of 2015 the City of Cordova Public Works
reported to Coffman that there is now 36 to 60 tons of annual cardboard. For Coffman’s analysis, the
annual cardboard supply is estimated at 50 tons per year. Burning 50 tons of cardboard will supply
approximately 22% of the pools annual heating needs.
Similar to cordwood, there is currently no commercial manufacturer or distributer of cardboard
briquettes. This is another economic opportunity that could be developed by a local business or
organization. Manufacturing of cardboard briquettes requires shredding the cardboard into feedstock
with a large shredding machine. The shredder is manually loaded with cardboard, paper or waste
construction wood. The shredding operation creates a significant amount of dust and so a dust collection
system is typically utilized. The cardboard feedstock is then transferred with an auger to a briquette press
machine that compresses the cardboard feedstock into solid briquettes in similar size to a hockey puck.
Photos of the shredder and briquette press manufactured by Weima are shown below.
Shredder (WLK-6)
81” long x 54” wide X 65” high
4,400 lbs
Briquette Press (TH-514)
82” long x 70” wide x 55” high
2,100 lbs
Figure 5 – Cardboard Shredder and Briquette Press
In order for the cardboard briquettes to be economical they must be less than heating oil on an energy
basis. The maximum cost for cardboard briquettes is $392/ton, which is equivalent to burning $4.00/gal
heating oil on an energy basis. However, the cost of the briquettes should be less than heating oil in order
to offer monetary savings to the Pool. A better price for the Pool would be if the cardboard briquettes
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were the same price as cordwood on an energy basis ($210/ton), or less. At this time the price for
purchasing cardboard briquettes is unknown and further analysis (such as a business plan) would be
required to get a more accurate selling price for cardboard briquettes.
Based on cardboard briquette prices above, selling 50 tons of cardboard to the Pool could bring in
between $10,500 to $19,600 in revenue to the business. To determine if this business is economical will
require a detailed business plan to determine equipment costs, labor costs, delivery costs as well has
other business related expenses. A building will also be required to house the equipment and operation.
Developing such a business plan is outside of the scope of this feasibility study. However, Coffman
contacted Weima America to help the City of Cordova get an idea of the budgetary equipment costs for
the shredding and briquetting machines. Budgetary costs for the basic components of the shredding and
briquetting system were provided by Mark Kunz of Weima and are shown below. A Weima WLK-6
shredder and TH-514 briquette press can produce 120 pounds per hour of briquettes. This system can
produce around 124 tons of briquettes annually if it’s operated 40 hours per week, so it will be able to
use all of Cordova’s current cardboard waste and have room for increased amounts of cardboard in the
future.
Table 4 – Energy Comparison
Equipment Budgetary Cost
Shredder (Model WLK-6) $40,000
Feed Auger from Shredder to Briquette Press $12,000
Briquette Press (Model TH-514) $40,000
Dust Collection System $10,000
Total Budgetary Equipment Cost $102,000
It is recommended that the City of Cordova further develop a business plan for a cardboard briquetting
system. As the cardboard and paper waste stream of the City increases, the business will become more
economical.
Wood Pellets
There is no local wood pellet manufacturer or distributer in Cordova, which means that wood pellets
would have to be barged into the community. Wood pellets are typically sold in 40 lb bags and shipped
by the pallet (where 50 bags are loaded on a pallet). Each pallet is one ton of pellets. Wood pellets are
currently sold in Anchorage for $295/ton. The cost for shipping one ton of wood pellets by barge to
Cordova was quoted by two companies (Lynden Transport and Samson Tug & Barge). Costs are around
$640/ton from Anchorage and $840/ton from Seattle. It is assumed that shipping rates will be reduced
by 15% if a substantial volume of pellets is shipped, due to economies of scale. For this report it is assumed
that shipping costs are $544/ton. The total cost of wood pellets will be $839/ton, which is more expensive
than heating oil or electricity on a BTU basis. Due to these factors, wood pellets was not considered as an
economical fuel for this study.
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Heating Oil
The high price of fuel oil is the main economic driver for the use of lower cost biomass heating. Fuel oil is
shipped into Cordova by barge and currently costs approximately $4.00/gal. For this study, the energy
content of fuel oil is based on 134,000 BTU/gal, according to the UAF Cooperative Extension.
Electricity
Electricity is provided by the local power utility, Cordova Electric Cooperative. According to the Pool’s
electric utility bills from 2014, the building has an effective electricity rate of approximately $0.20/kWh.
This rate is used in the economic analysis.
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Existing Fuel Oil Consumption
An estimate of the Pool’s heating oil consumption was made based on heating oil bills from 2013 and
2014. On average the Pool consumes approximately 22,000 gal of fuel oil annually for heating needs. The
estimated annual fuel cost, based on the current price of heating oil, is $88,000.
Table 5 – Existing Fuel Oil Consumption
Building Fuel Type Annual Consumption Net MMBTU/yr Avg. Annual
Cost
Pool Fuel Oil 22,000 gal 2358.4 $88,000
Biomass System Consumption
It is estimated that the proposed biomass system will offset 64% of the heating energy for the building,
by burning cordwood. The remaining 36% of the heating energy will be provided by the existing oil boilers.
This result is based on an analysis of the pool’s annual heating oil consumption and the heat output of the
Garn boiler. It is assumed that the Garn WHS-3200 is loaded every 12 hours, which will produce 176,000
BTU/hr per manufacturer documentation. More frequent loading is possible, which will increase BTU
output and allow additional heating oil offset during colder times of the year. Overall, the Garn system
will save approximately $26,063 of heating oil annually.
Table 6 – Proposed Biomass System Fuel Consumption
Building Fuel Type % Heating
Source
Net
MMBTU/yr
Annual
Consumption
Energy
Cost
Total
Energy
Cost
Annual
Energy
Savings
Pool
Cordwood 64% 1509.4 134 cords $30,208
$61,938 $26,062 Fuel Oil 36% 849.0 7,920 gal $31,680
Additional
Electricity N/A N/A 250 kWh $50
Burning cardboard briquettes in the proposed Garn boiler is also possible. However, an economic analysis
for burning cardboard briquettes was not completed because a business plan will be required to
determine an accurate selling price.
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V. Preliminary Cost Estimating
An estimate of probable costs was completed for installing the Garn boiler system. The cost estimate is
based equipment quotes and from previous cost estimates created for similar projects. A 10% remote
factor was used to account for increased shipping and installation costs in Cordova. Project and
Construction Management was estimated at 5%. Engineering design and permitting was estimated at
20% and a 15% contingency was used.
Table 7 – Estimate of Probable Cost
Category Description Cost
Site Work Site Grading for Conex $ 4,000
Foundation (Timbers and Anchors) $ 5,000
Buried Utilities $ 5,000
Subtotal $ 14,000
Electrical Utilities Service Entrance $ 5,000
Conduit and Wiring $ 5,000
Subtotal $ 10,000
Wood Boiler Conex Insulated Conex 8 ft x 20 ft $ 15,000
Garn Boiler WHS 3200 $ 46,500
Heat Exchanger $ 5,000
Installation, Piping & Materials $ 45,000
Fire Allowance $ 6,000
Controls Allowance $ 5,000
Electrical Allowance $ 6,000
Shipping $ 30,000
Site Installation $ 10,000
Subtotal $ 168,500
Pool Building Mechanical Pool Heat Exchanger $ 5,000
Installation, Piping & Materials $ 10,000
Subtotal $ 15,000
Subtotal Material and Installation Cost $ 207,500
Remote Factor 10% $ 20,750
Subtotal $ 228,250
Project and Construction Management 5% $ 11,413
Subtotal $ 239,663
Design Fees and Permitting 20% $ 47,932
Subtotal $ 287,595
Contingency 15% $ 43,139
Total Project Cost $ 330,734
Feasibility Assessment for Biomass Heating Systems Cordova, AK
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VI. Economic Analysis
The following assumptions were used to complete the economic analysis for this study.
Table 8 – Inflation rates
Discount Rate for Net Present Value Analysis 3%
Wood Fuel Escalation Rate 3%
Fossil Fuel Escalation Rate 5%
Electricity Escalation Rate 3%
O&M Escalation Rate 2%
The real discount rate, or minimum attractive rate of return, is 3.0% and is the current rate used for all
Life Cycle Cost Analysis by the Alaska Department of Education and Early Development. This is a typical
rate used for completing economic analysis for public entities in Alaska. The escalation rates used for the
wood, heating oil, electricity and O&M rates are based on rates used in the Alaska Energy Authority
funded 2013 and 2014 biomass pre-feasibility studies. These are typical rates used for this level of
evaluation and were used so that results are consistent and comparable to the previous studies.
O&M Costs
Non-fuel related operations and maintenance costs (O&M) were estimated at $400 per year. The
estimate is based on annual maintenance time for the Garn boiler. For only the first two years of service,
the maintenance cost is doubled to account for maintenance staff getting used to operating the new
system. Labor costs for daily stoking of the boiler are not included, as this is typically completed by a
maintenance person who is already hired by the organization that utilizes the boiler and stoking the boiler
would become part of their daily duties.
Definitions
There are many different economic terms used in this study. A listing of all of the terms with their
definition is provided below for reference.
Table 9 – Economic Definitions
Economic Term Description
Project Capital Cost This is the opinion of probable cost for designing and constructing the
project.
Simple Payback The Simple Payback is the Project Capital Cost divided by the first year annual
energy savings. The Simple Payback does not take into account escalated
energy prices and is therefore not a good measure of project viability.
𝑅𝑖𝑖𝑖𝑖𝑎 𝑂𝑎𝑦𝑎𝑎𝑎𝑖= 𝐼𝑖𝑟𝑟𝑎𝑖𝑖𝑎𝑎 𝐵𝑖𝑟𝑟 𝑖𝑎 𝐸𝐵𝑀
𝐸𝑖𝑟𝑟𝑟 𝑌𝑎𝑎𝑟 𝐸𝑖𝑎𝑟𝑎𝑦 𝑅𝑎𝑣𝑖𝑖𝑎𝑟 𝑖𝑎 𝐸𝐵𝑀
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Table 9 – Economic Definitions
Economic Term Description
Present Value of
Project Benefits
(20 year life)
The present value of all of the heating oil that would have been consumed
by the existing heating oil-fired heating system, over a 20 year period.
Present Value of
Operating Costs
(20 year life)
The present value of all of the proposed biomass systems operating costs
over a 20 year period. This includes wood fuel, additional electricity, and
O&M costs for the proposed biomass system and the heating oil required by
the existing equipment to supply the remaining amount of heat to the
building.
Benefit / Cost Ratio of
Project
(20 year life)
This is the benefit to cost ratio over the 20 year period. A project that has a
benefit to cost ratio greater than 1.0 is economically justified. It is defined
as follows:
𝐵𝑎𝑖𝑎𝑎𝑖𝑟 / 𝐵𝑖𝑟𝑟 𝑅𝑎𝑟𝑖𝑖
= 𝑂𝑉(𝑂𝑟𝑖𝑖𝑎𝑎𝑟 𝐵𝑎𝑖𝑎𝑎𝑖𝑟𝑟)− 𝑂𝑉(𝑂𝑖𝑎𝑟𝑎𝑟𝑖𝑖𝑎 𝐵𝑖𝑟𝑟𝑟)
𝑂𝑟𝑖𝑖𝑎𝑎𝑟 𝐵𝑎𝑖𝑖𝑟𝑎𝑖 𝐵𝑖𝑟𝑟
Where:
PV = The present value over the 20 year period
Reference Sullivan, Wicks and Koelling, “Engineering Economy”, 14th ed.,
2009, pg. 440, Modified B-C Ratio.
Net Present Value
(20 year life)
This is the net present value of the project over a 20 year period. If the
project has a net present value greater than zero, the project is economically
justified. This quantity accounts for the project capital cost, project benefits
and operating costs.
Year Accumulated Cash
Flow > Project Capital
Cost
This is the number of years it takes for the accumulated cash flow of the
project to be greater than or equal to the project capital cost. This is similar
to the project’s simple payback, except that it incorporates the inflation
rates. This quantity is the payback of the project including escalating energy
prices and O&M rates. This quantity is calculated as follows:
𝐼𝑖𝑟𝑟𝑎𝑖𝑖𝑎𝑎 𝐵𝑖𝑟𝑟≤∑𝑅𝑘
𝐽
𝑘=0
Where:
J = Year that the accumulated cash flow is greater than or equal to the
Project Capital Cost.
𝑅𝑘 = Project Cash flow for the kth year.
Feasibility Assessment for Biomass Heating Systems Cordova, AK
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Results
An economic analysis was completed in order to determine the simple payback, benefit to cost ratio, and
net present value of the proposed Garn boiler system, as shown in the table below. The Garn boiler would
be located in a detached conex and heating pipes would connect to the new heat exchanger in the Pool’s
mechanical room. The Garn would be dedicated to heating the pool water, in order to take advantage of
lower heating water temperatures and overall higher wood boiler efficiencies. The existing heating oil
boiler would still be used to heat the rest of the facility and supplement the pool water heating when
needed. A cordwood storage building was not included in this analysis. If possible, combining the new
office building stairwell to act as wood storage could save storage facility costs.
The proposed Garn boiler project has a benefit to cost ratio of 2.20 over the 20 year study period, which
makes the project economically justified. Any project with a benefit to cost ratio above 1.0 is considered
economically justified. The main reason the project is viable is because of the large quantity of heating
oil savings compared to the relatively low price of cordwood.
Please refer to Appendix B for the economic analysis spreadsheet for greater detail.
Table 10 – Economic Analysis Results
Project Capital Cost $330,734
Present Value of Project Benefits (20 year life) $2,063,893
Present Value of Operating Costs (20 year life) $1,337,273
Benefit / Cost Ratio of Project (20 year life) 2.20
Net Present Value (20 year life) $395,886
Year Accumulated Cash Flow is Net Positive First Year
Year Accumulated Cash Flow > Project Capital Cost 11 years
Simple Payback 13.1 years
It was found that if a pool dehumidification system is installed the Benefit / Cost Ratio of the biomass
project will also be 2.20. This is because the present value of project benefits and operating costs are
both reduced by the same amount, due to the heating oil savings of the new dehumidification system and
because the biomass system only offsets a percentage of the total heat requirement.
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Sensitivity Analysis
A sensitivity analysis was completed to show how changing heating oil costs and wood costs affect the
benefit to cost (B/C) ratios of the project. As heating oil costs increase and wood costs decrease, the
project becomes more economically viable. The B/C ratios greater than 1.0 are economically justified and
are highlighted in green. B/C ratios less than 1.0 are not economically justified and are highlighted in red.
Table 11 – Sensitivity Analysis
B/C Ratios Cordwood Cost
$200/cord $225/cord $300/cord $350/cord
Heating Oil Cost
$3.50/gal 1.89 1.70 1.11 0.71
$3.75/gal 2.14 1.95 1.36 0.96
$4.00/gal 2.39 2.20 1.61 1.21
$4.25/gal 2.64 2.45 1.86 1.46
$4.50/gal 2.89 2.70 2.11 1.71
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VII. Forest Resource and Fuel Availability Assessments
Forest Resource Assessments
In 2012 the Department of Natural Resources Division of Forestry wrote the “Assessment of Woody
Biomass Energy Resources in the Cordova Area”. This Forest Resource Assessment is a great resource that
quantifies timber resources in the Cordova Area for biomass heating.
Air Quality Permitting
Currently, air quality permitting is regulated according to the Alaska Department of Environmental
Conservation Section 18 AAC 50 Air Quality Control regulations. Per these regulations, a minor air quality
permit is required if a new wood boiler or wood stove produces one of the following conditions per
Section 18 AAC 50.502 (C)(1): 40 tons per year (TPY) of carbon dioxide (CO2), 15 TPY of particulate matter
greater than 10 microns (PM-10), 40 TPY of sulfur dioxide, 0.6 TPY of lead, 100 TPY of carbon monoxide
within 10 kilometers of a carbon monoxide nonattainment area, or 10 TPY of direct PM -2.5 emissions.
These regulations assume that the device will operate 24 hours per day, 365 days per year and that no
fuel burning equipment is used. If a new wood boiler or wood stove is installed in addition to a fuel
burning heating device, the increase in air pollutants cannot exceed the following per AAC 50.502 (C)(3):
10 TPY of PM-10, 10 TPY of sulfur dioxide, 10 TPY of nitrogen oxides, 100 TPY of carbon monoxide within
10 kilometers of a carbon monoxide nonattainment area, or 10 TPY of direct PM-2.5 emissions. Per the
Wood-fired Heating Device Visible Emission Standards (Section 18 AAC 50.075), a person may not operate
a wood-fired heating device in a manner that causes black smoke or visible emissions that exceed 50
percent opacity for more than 15 minutes in any hour in an area where an air quality advisory is in effect.
From Coffman’s discussions with Patrick Dunn at the Alaska Department of Environmental Conservation,
these regulations are focused on permitting industrial applications of wood burning equipment. In his
opinion, it would be unlikely that an individual wood boiler would require an air quality permit unless
several boilers were to be installed and operated at the same site. If several boilers were installed and
operated together, the emissions produced could be greater than 40 tons of CO2 per year. This would
require permitting per AAC 50.502 (C)(1) or (C)(3). Permitting would not be required on the residential
wood fired stoves unless they violated the Wood-fired Heating Device Visible Emission Standards (Section
18 AAC 50.075). Recent Garn boiler systems installed in Alaska have not required air quality permits.
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VIII. General Biomass Technology Information
Heating with Wood Fuel
Wood fuels are among the most cost-effective and reliable sources of heating fuel for communities
adjacent to forestland when the wood fuels are processed, handled, and combusted appropriately.
Compared to other heating energy fuels, such as oil and propane, wood fuels typically have lower energy
density and higher associated transportation and handling costs. Due to this low bulk density, wood fuels
have a shorter viable haul distance when compared to fossil fuels. This short haul distance also creates an
advantage for local communities to utilize locally-sourced wood fuels, while simultaneously retaining local
energy dollars.
Most communities in rural Alaska are particularly vulnerable to high energy prices due to the large number
of heating degree days and expensive shipping costs. For many communities, wood-fueled heating can
lower fuel costs. For example, cordwood sourced at $250 per cord is just 25% of the cost per MMBTU as
#1 fuel oil sourced at $7 per gallon. In addition to the financial savings, the local communities also benefit
from the multiplier effect of circulating energy dollars within the community longer, more stable energy
prices, job creation, and more active forest management.
The local cordwood market is influenced by land ownership, existing forest management and ecological
conditions, local demand and supply, and the State of Alaska Energy Assistance program.
Types of Wood Fuel
Wood fuels are specified by energy density, moisture content, ash content, and granulometry. Each of
these characteristics affects the wood fuel’s handling characteristics, storage requirements, and
combustion process. Higher quality fuels have lower moisture, ash, dirt, and rock contents, consistent
granulometry, and higher energy density. Different types of fuel quality can be used in wood heating
projects as long as the infrastructure specifications match the fuel content characteristics. Typically, lower
quality fuel will be the lowest cost fuel, but it will require more expensive storage, handling, and
combustion infrastructure, as well as additional maintenance.
Projects in rural Alaska must be designed around the availability of wood fuels. Some fuels can be
harvested and manufactured on site, such as cordwood, woodchips, and briquettes. Wood pellets can
also be used, but typically require a larger scale pellet manufacturer to make them. The economic
feasibility of manufacturing on site is determined by a financial assessment of the project. Typically, larger
projects offer more flexibility in terms of owning and operating the wood harvesting and manufacturing
equipment, such as a wood chipper, splitter, or equipment to haul wood out of forest, than smaller
projects.
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High Efficiency Wood Pellet Boilers
High efficiency pellet boilers are designed to burn wood pellets cleanly and efficiently. These boilers utilize
pellet storage bins or silos that hold a large percentage of the building’s annual pellet supply. Augers or
vacuums transfer pellets from the silos to a pellet hopper adjacent to the pellet boiler, where pellets can
be fed into the boiler for burning. Pellets are automatically loaded into the pellet boiler and do not require
manual loading such as in a Garn cordwood boiler. The pellet boilers typically have a 3 to 1 turn down
ratio, which allows the firing rate to modulate from 100% down to 33% fire. This allows the boiler to
properly match building heat demand, increasing boiler efficiency. The efficiencies of these boilers can
range from 85% to 92% efficiency depending on firing rate.
Two of the best quality pellet boilers in the U.S. market are the Maine Energy Systems PES boilers and the
Froling P4 boilers. These boilers have high end controls, automatic ash removal and have a good
reputation for quality. The Maxim Pellet Boiler is a less costly option and can be used directly outdoors if
needed. According to Chad Shumacher, General Manager of Superior Pellets, his Maxim boiler
automation does not operate as well as the Maine Energy Systems units, but they are less than half the
price. The working lifespan of the Maxim boilers also may be less than the higher quality units.
High Efficiency Cordwood Boilers
High Efficiency Low Emission (HELE) cordwood boilers are designed to burn cordwood fuel cleanly and
efficiently. The boilers use cordwood that is typically seasoned to 25% moisture content (MC) or less and
meet the dimensions required for loading and firing. The amount of cordwood burned by the boiler will
depend on the heat load profile of the building and the utilization of the fuel oil system as back up. Two
HELE cordwood boiler suppliers include Garn (www.garn.com) and TarmUSA (www.woodboilers.com).
Both of these suppliers have units operating in Alaska. TarmUSA has a number of residential units
operating in Alaska and has models that range between 100,000 to 300,000 BTU/hr. Garn boilers,
manufactured by Dectra Corporation, are used in Tanana, Kasilof, Dot Lake, Thorne Bay, Coffman Cove
and other locations to heat homes, washaterias, schools, and community buildings.
The Garn boiler has a unique construction, which is basically a wood boiler housed in a large water tank.
Garn boilers come in several sizes and are appropriate for facilities using 100,000 to 1,000,000 BTUs per
hour. The jacket of water surrounding the fire box absorbs heat and is piped into buildings via a heat
exchanger, and then transferred to an existing building heating system, infloor radiant tubing, unit
heaters, or baseboard heaters. In installations where the Garn boiler is in a detached building, there are
additional heat exchangers, pumps and a glycol circulation loop that are necessary to transfer heat to the
building while allowing for freeze protection. Radiant floor heating is the most efficient heating method
when using wood boilers such as Garns, because they can operate using lower supply water temperatures
compared to baseboards.
Garn boilers are approximately 87% efficient and store a large quantity of water. For example, the Garn
WHS-2000 holds approximately 1,825 gallons of heated water. Garns also produce virtually no smoke
when at full burn, because of a primary and secondary gasification (2,000 ºF) burning process. Garns are
manually stocked with cordwood and can be loaded multiple times a day during periods of high heating
demand. Garns are simple to operate with only three moving parts: a handle, door and blower. Garns
produce very little ash and require minimal maintenance. Removing ash and inspecting fans are typical
maintenance requirements. Fans are used to produce a draft that increases combustion temperatures
and boiler efficiency. In cold climates, Garns can be equipped with exterior insulated storage tanks for
extra hot water circulating capacity. Most facilities using cordwood boilers keep existing oil-fired systems
Feasibility Assessment for Biomass Heating Systems Cordova, AK
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operational to provide heating backup during biomass boiler downtimes and to provide additional heat
for peak heating demand periods.
Low Efficiency Cordwood Boilers
Outdoor boilers are categorized as low-efficiency, high emission (LEHE) systems. These boiler systems are
not recommended as they produce significant emission issues and do not combust wood fuels efficiently
or completely, resulting in significant energy waste and pollution. These systems require significantly
more wood to be purchased, handled and combusted to heat a facility as compared to a HELE system.
Additionally, several states have placed a moratorium on installing LEHE boilers because of air quality
issues (Washington). These LEHE systems can have combustion efficiencies as low as twenty five (25%)
percent and produce more than nine times the emission rate of standard industrial boilers. In comparison,
HELEs can operate around 87% efficiency.
High Efficiency Wood Stoves
Newer high efficiency wood stoves are available on the market that produce minimal smoke, minimal ash
and require less firewood. New EPA-certified wood stoves produce significantly less smoke than older
uncertified wood stoves. High efficiency wood stoves are easy to operate with minimal maintenance
compared to other biomass systems. The Blaze King Classic high efficiency wood stove
(www.blazeking.com) is a recommended model, due to its built-in thermostats that monitor the heat
output of the stove. This stove automatically adjusts the air required for combustion. This unique
technology, combined with the efficiencies of a catalytic combustor with a built-in thermostat, provides
the longest burn times of any wood stove. The Blaze King stove allows for optimal combustion and less
frequent loading and firing times.
Bulk Fuel Boilers
Bulk fuel boilers usually burn wood chips, sawdust, bark or pellets and are designed around the wood
resources that are available from the local forests or local industry. Several large facilities in Tok, Craig,
and Delta Junction (Delta Greely High School) are using bulk fuel biomass systems. Tok uses a commercial
grinder to process woodchips. The chips are then dumped into a bin and are carried by a conveyor belt
to the boiler. The wood fuel comes from timber scraps, local sawmills and forest thinning projects. The
Delta Greely High School has a woodchip bulk fuel boiler that heats the 77,000 square foot facility. The
Delta Greely system, designed by Coffman engineers, includes a completely separate boiler building which
includes a chip storage bunker and space for storage of tractor trailers full of chips (so handling of frozen
chips could be avoided). Woodchips are stored in the concrete bunker and augers move the material on
a conveyor belt to the boilers.
Grants
There are many grant opportunities for biomass work state, federal, and local for feasibility studies, design
and construction. If a project is pursued, a thorough search of websites and discussions with the AEA
Biomass group would be recommended to make sure no possible funding opportunities are
missed. Below are some funding opportunities and existing past grants that have been awarded.
Currently, there is a funding opportunity for tribal communities that develop clean and renewable energy
resources through the U.S. Department of Energy. On April 30, 2013, the Department of Energy
announced up to $7 million was available to deploy clean energy projects in tribal communities to reduce
reliance on fossil fuel and promote economic development on tribal lands. The Energy Department’s Tribal
Feasibility Assessment for Biomass Heating Systems Cordova, AK
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Energy Program, in cooperation with the Office of Indian Energy, will help Native American communities,
tribal energy resource development organizations, and tribal consortia to install community or facility
scale clean energy projects.
http://apps1.eere.energy.gov/tribalenergy/
The Department of Energy (DOE), Alaska Native programs, focus on energy efficiency and add ocean
energy into the mix. In addition the communities are eligible for up to $250,000 in energy-efficiency aid.
The Native village of Kongiganak will get help strengthening its wind-energy infrastructure, increasing
energy efficiency and developing “smart grid technology”. Koyukuk will get help upgrading its energy
infrastructure, improving energy efficiency and exploring biomass options. The village of Minto will
explore all the above options as well as look for solar-energy ideas. Shishmaref, an Alaska Native village
faced climate-change-induced relocation, will receive help with increasing energy sustainability and
building capacity as it relocates. And the Yakutat T’lingit Tribe will also study efficiency, biomass and ocean
energy. This DOE program would be a viable avenue for biomass funding.
http://energy.gov/articles/alaska-native-communities-receive-technical-assistance-local-clean-energy-
development
The city of Nulato was awarded a $40,420 grant for engineering services for a wood energy project by the
United States Department of Agriculture (USDA) and the United States Forest Service. Links regarding the
award of the Woody Biomass Utilization Project recipients are shown below:
http://www.fs.fed.us/news/2012/releases/07/renewablewoods.shtml
http://www.usda.gov/wps/portal/usda/usdahome?contentid=2009/08/0403.xml
Delta Junction was awarded a grant for engineering from the Alaska Energy Authority from the Renewable
Energy Fund for $831,203. This fund provides assistance to utilities, independent power producers, local
governments, and tribal governments for feasibility studies, reconnaissance studies, energy resource
monitoring, and work related to the design and construction of eligible facilities.
http://www.akenergyauthority.org/re-fund-6/4_Program_Update/FinalREFStatusAppendix2013.pdf
http://www.akenergyauthority.org/PDF%20files/PFS-BiomassProgramFactSheet.pdf
http://www.akenergyauthority.org/RenewableEnergyFund/RFA_Project_Locations_20Oct08.pdf
The Alaska Wood Energy Development Task Group (AWEDTG) consists of a coalition of federal and state
agencies and not-for-profit organizations that have signed a Memorandum of Understanding (MOU) to
explore opportunities to increase the utilization of wood for energy and biofuels production in Alaska. A
pre-feasibility study for Aleknagik was conducted in 2012 for the AWEDTG. The preliminary costs for the
biomass system(s) are $346,257 for the city hall and health center system and $439,096 for the city hall,
health center, and future washeteria system.
http://www.akenergyauthority.org/biomasswoodenergygrants.html
http://www.akenergyauthority.org/BiomassWoodEnergy/Aleknagik%20Final%20Report.pdf
The Emerging Energy Technology Fund grand program provides funds to eligible applicants for
demonstrations projects of technologies that have a reasonable expectation to be commercially viable
Feasibility Assessment for Biomass Heating Systems Cordova, AK
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within five years and that are designed to: test emerging energy technologies or methods of conserving
energy, improve an existing energy technology, or deploy an existing technology that has not previously
been demonstrated in Alaska.
http://www.akenergyauthority.org/EETFundGrantProgram.html
Feasibility Assessment for Biomass Heating Systems Cordova, AK
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Appendix A
Site Photos
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1. South elevation of building 2. West elevation of building
3. North elevation of building 4. East elevation of building
5. Site entrance 6. Approximate location of new biomass
building on north side of building
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7. Inside Pool 8. Boiler Room
9. Domestic Hot Water Pumps and Heaters 10. Inside Pool
11. Site Entrance 12. Heating Oil Tank
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13. Main Electrical Panel 14. Electrical Panel
15. Electrical Service 16. Boiler Burner
Feasibility Assessment for Biomass Heating Systems Cordova, AK
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Appendix B
Economic Analysis Spreadsheet
Bob Korn Memorial Swimming PoolCordova, AlaskaProject Capital Cost($330,734)Present Value of Project Benefits (20 year life)$2,063,893Present Value of Operating Costs (20 year life)($1,337,273)Benefit / Cost Ratio of Project (20 year life)2.20Net Present Value (20 year life)$395,886.19Year Accumulated Cash Flow is Net PositiveFirst YearYear Accumulated Cash Flow > Project Capital Cost11 yearsSimple Payback = Total Project Cost / First Year Cost Savings13.1 yearsDiscount Rate for Net Present Value Analysis3%Wood Fuel Escalation Rate3%Fossil Fuel Escalation Rate5%Electricity Escalation Rate3%O&M Escalation Rate2%YearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYearYear1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20Existing Heating System Operating CostsExisting Heating Oil Consumption$4.0022,000gal$88,000$92,400$97,020$101,871$106,965$112,313$117,928$123,825$130,016$136,517$143,343$150,510$158,035$165,937$174,234$182,946$192,093$201,698$211,782$222,372Biomass System Operating CostsCord Wood (Delivered to site)$225.0064%134.0cords($30,150)($31,055)($31,986)($32,946)($33,934)($34,952)($36,001)($37,081)($38,193)($39,339)($40,519)($41,735)($42,987)($44,276)($45,605)($46,973)($48,382)($49,833)($51,328)($52,868)Fossil Fuel$4.0036%7,920gal($31,680)($33,264)($34,927)($36,674)($38,507)($40,433)($42,454)($44,577)($46,806)($49,146)($51,603)($54,184)($56,893)($59,737)($62,724)($65,860)($69,153)($72,611)($76,242)($80,054)Additional Electricity$0.20250kWh($50)($52)($53)($55)($56)($58)($60)($61)($63)($65)($67)($69)($71)($73)($76)($78)($80)($83)($85)($88)Operation and Maintenance Costs($400)($408)($416)($424)($433)($442)($450)($459)($469)($478)($488)($497)($507)($517)($528)($538)($549)($560)($571)($583)Additional Operation and Maintenance Costs for first 2 years($400)($408)$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0$0Total Operating Costs($62,680)($65,186)($67,383)($70,098)($72,931)($75,884)($78,965)($82,179)($85,531)($89,028)($92,677)($96,485)($100,458)($104,605)($108,932)($113,449)($118,165)($123,087)($128,226)($133,592)Annual Operating Cost Savings$25,320 $27,214 $29,637 $31,773 $34,034 $36,428 $38,963 $41,646 $44,485 $47,489 $50,665 $54,025 $57,577 $61,333 $65,302 $69,496 $73,928 $78,610 $83,556 $88,779Accumulated Cash Flow$25,320 $52,534 $82,171 $113,944 $147,978 $184,407 $223,370 $265,016 $309,501 $356,990 $407,655 $461,680 $519,258 $580,590 $645,892 $715,388 $789,317 $867,927 $951,483 $1,040,262Net Present Value($306,151.48) ($280,499.67) ($253,377.20) ($225,147.65) ($195,789.65) ($165,281.38) ($133,601) ($100,725) ($66,631) ($31,295)$5,307 $43,199 $82,407 $122,955 $164,870 $208,177 $252,905 $299,080 $346,731 $395,886Economic Analysis ResultsInflation RatesDescription Unit CostHeating Source ProportionAnnual Energy UnitsEnergy Units
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Appendix C
AWEDTG Field Data Sheet