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RFA AEA 09-004 Application Cost Worksheet revised 9/26/08 Page 1
Application Cost Worksheet
Please note that some fields might not be applicable for all technologies or all project
phases. Level of information detail varies according to phase requirements.
1. Renewable Energy Source
The Applicant should demonstrate that the renewable energy resource is available on a
sustainable basis.
Annual average resource availability. This project will assess the feasibility of solar hot water
heating systems on residential units in the Northwest
Arctic Borough, as well as commercial and public
buildings.
Unit depends on project type (e.g. windspeed, hydropower output, biomasss fuel)
On average, the daily solar radiation flux for Northwest Alaska ranges between 2 to 3 kWh/sq. meter. For solar
space heating, the most economic time of year in Northwest Alaska would be around the equinoxes of September
and March. These are times of year when there are 12 hours of daylight per day, and the average air temperature
in Northwest Alaska is cold enough to justify space heating.
2. Existing Energy Generation
a) Basic configuration (if system is part of the Railbelt1 grid, leave this section blank)
i. Number of generators/boilers/other
The hot water heaters in the buildings of the Northwest Arctic Borough School District ar e part of a heating plant,
which is separated from the main building. An example of this is the Kotzebue school, where water is heated
indirectly with hot glycol from a boiler module, which also provides space heating. The boiler water heats the
schools two huge plate and frame heat exchangers where the schools glycol/water -heating medium is heated. Hot
glycol is then circulated through a plate type heat exchanger (for 115 degree water) and an Amtrol hot water
maker for 140-degree hot water. During the warmest months of the school year, the school must run a boiler to
make hot water. One boiler contains 385 gallons of water, the piping that connects it with the plate and frame
heat exchangers contain approximately 200 gallons. Thus there are times when the school does not need space
heating, but does need hot water.
ii. Rated capacity of generators/boilers/other
iii. Generator/boilers/other type
iv. Age of generators/boilers/other
v. Efficiency of generators/boilers/other
1 The Railbelt grid connects all customers of Chugach Electric Association, Homer Electric Association, Golden
Valley Electric Association, the City of Seward Electric Department, Matanuska Electric Association and Anchorage
Municipal Light and Power.
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RFA AEA 09-004 Application Cost Worksheet revised 9/26/08 Page 2
b) Annual O&M cost (if system is part of the Railbelt grid, leave this section blank)
i. Annual O&M cost for labor
ii. Annual O&M cost for non-labor
c) Annual electricity production and fuel usage (fill in as applicable) (if system is part of the
Railbelt grid, leave this section blank)
i. Electricity [kWh]
ii. Fuel usage
Diesel [gal]
Other
iii. Peak Load
iv. Average Load
v. Minimum Load
vi. Efficiency[kwh/gal]
vii. Future trends
d) Annual heating fuel usage (fill in as applicable)
i. Diesel [gal or MMBtu] 800-1000 gallons/year for 700 sq foot home;
4000 sq ft commercial building approximately 3000
gallons/year
ii. Electricity [kWh]
iii. Propane [gal or MMBtu]
iv. Coal [tons or MMBtu]
v. Wood [cords, green tons, dry tons]
vi. Other
3. Proposed System Design
Solar hot water heating could be practical in Northwest Alaska for up to nine months of the year. About 50% of
annual hot water heating needs in Kotzebue could be met by solar.
Solar photovoltaic (PV) power generation also could be practical during late spring and summer, and is being
studied for applications in Northwest Alaska by the Alaska Village Electric Cooperative. Solar thermal power
generation (using steam turbines) is not likely to be practical in Northwest Alaska.
For mounting solar collector panels, a vertical panel surface (a 90° angle from the ground) would be best in
Northern Alaska. Such a vertical mounting mitigates the accumulation of snow or ice. South -facing walls on
existing buildings can be adapted for this purpose. Our proposed design would be for solar radiation for flat plate
collectors facing south at a fixed tilt (uncertainty of (+-9%).
a) Installed capacity The thermal requirements are 40-50,000 btu/per
residence. Assuming water must be heated from 35° to
120°F.
b) Annual renewable electricity generation
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RFA AEA 09-004 Application Cost Worksheet revised 9/26/08 Page 3
i. Diesel [gal or MMBtu] 125-175 gallons of displaced fuel (25-30% displacement for
solar hot water heating)
Hot water heating constitutes approximately 50% of a
households annual heating diesel fuel use.
ii. Electricity [kWh]
iii. Propane [gal or MMBtu]
iv. Coal [tons or MMBtu]
v. Wood [cords, green tons, dry tons]
vi. Other
4. Project Cost
a) Total capital cost of new system Assumed at $8-10,000 per home.
Approximately $10,000-50,000 for a commercial building
on scale with what is found in NW Alaska.
b) Development cost Development cost is assumed to be 5-15% of capital
costs.
c) Annual O&M cost of new system Approximately $500/year on a commercial building;
Negligible on residential unit
d) Annual fuel cost A 700 sq ft home uses approximately 1000 gallons/yr of
diesel fuel. Assuming the price of home heating fuel in
Noatak, that amounts to $8,500/yr in total ($4,250 for hot
water heating and $4,250 for space heating) for a
residence.
5. Project Benefits
a) Amount of fuel displaced for
i. Electricity
ii. Heat For a residential unit, it is estimated that a solar hot water system can displace 25-
30% of heating fuel needs (assume 50% of domestic heating oil is used for hot
water and 50% is used for home heating; and 1000 gallons annual home heating)
Using these parameters, a hot water solar system can displace 125-150 gallons/yr
per home. This technology can save targeted households approximately $800-
1200/yr depending on the price of fuel.
iii. Transportation
b) Price of displaced fuel Price of displaced fuel anywhere from $3.80 in Deering to -
8.50 in Noatak.
Assuming a 20 year lifecycle of the installed unit, price of
fuel at $8.49, a 3.5% inflation rate on the price of fuel, the
proposed technology could save $36,000 over the life of the
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RFA AEA 09-004 Application Cost Worksheet revised 9/26/08 Page 4
project.
c) Other economic benefits The project also has the benefit of reducing spills and other
environmental benefits.
d) Amount of Alaska public benefits
6. Power Purchase/Sales Price
a) Price for power purchase/sale N/A
7. Project Analysis
a) Basic Economic Analysis
Project benefit/cost ratio 1.9
Payback 13 years