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HomeMy WebLinkAboutCity of Atka - Chuniixsax Creek Hydro - REF Grant 2195376 2015Atka, Alaska Hydro project displaces 80% of diesel electric fuel in first Quick Facts Total Project Costs: $5,000,000 Funding: Renewable Energy Fund, Denali Com- mission funding, & local matching funds Capital Costs Design: $600,000 Construction: $4,400,000 Projects Specs Gen. Set Make/Model: Ossberger Cross Flow Output: 284 kW Hydraulic Capacity: 37 cubic feet per second (cfs) Reservoir Storage Volume: 73.8 acre feet Static Head: 118feet Annual Energy Generation: 1,757,412 Kwh Diesel Fuel Offset Estimated Annual: 27,280 gallons Actual Annual: 23,000 gallons Fuel Savings Estimated Annual: $150,000 Actual Annual: $121,000 2012-2014: $284,000 Chuniixsax Creek Hydroelectric Project Project Overview In partnership with the Alaska Energy Authority (AEA), the City of Atka completed the final design, permitting, and construction of a hydroelectric dam on Chuniixsax Creek. New transmission lines from the powerhouse to the city were constructed in ad- dition to new diesel plant controls and interface. The powerhouse now provides up to 284 kW of renewable energy to the community. It is able to meet residential and public facility needs and also supplies a portion of energy needed by Atka Pride Seafoods during the summer months. Objectives The main objectives of this project were to reduce electrical costs to the City of Atka by using a renew- able resource and to reduce residents’ dependency on expensive and volatile diesel fuel. Project Performance The project became operational in December of 2012. Between December of 2012 and December of 2014, it generated 1,040 MWh of electricity and displaced 75,000 gallons of diesel fuel. This displacement saved the community of Atka $388,000 in reduced energy costs in two years. Project Specifications The diesel powerhouse is located in the center of town and contains 3 diesel generators that remain as a backup power source if the load from the dam is insufficient. The construction of the 12.5 feet high concrete dam, 952 feet of HDPE, and 50 feet of steel penstock were undertaken by the City of Atka acting as the prime contractor. Local labor was supplement- ed by imported personnel possessing special skills in construction. The Atka Electric Utility runs the powerhouse and does daily maintenance and inspec- Chuniixsax Creek powerhouse, photo courtesy of Michael Dahl. tion on plant output and performance. The project utilizes a peak flow of 18 cubic feet per second (cfs) and displaced 80% of the community’s electrical needs in the first year. Allocation of Funding The Renewable Energy Fund contributed $996,000 and local funds contributed $2,013,299. REF money went toward design and construction, and local funds went toward design, construction, and overhead costs like maintenance and interest. Other sources of funding in- cluded the Denali Commission, USDOE Rural Utility Services, Aleutian/Pribilof Islands Community Devel- opment Association, and several other institutions. Learning Experiences/Challenges A few challenges the project encountered included extreme weather conditions, logistics, and competition for use of available equipment. Construction began in 2004, but due to a lack of funding early on, the proj- ect was put to a halt and was restarted again in 2008 when the city acquired additional funding. During construction, delays in getting personnel and materi- als made construction time exceed what was planned as well. Ash overburden and the wet environment in Atka required erosion protection in most work areas that disturbed the vegetative mat. Disturbed areas were later re-seeded with native grass species. Community Benefits This project was feasible for the City of Atka largely because they were finally able to cut electricity costs by displacing expensive diesel fuel. Atka current- ly pays about $7.50 per gallon for heating fuel, and each household uses about 100 gallons per month. This equates to $750/month, and they have to pay for electricity on top of that. Electricity from the commu- nity’s diesel generators costs 76 cents a kilowatt hour, compared to 27 cents a kilowatt hour for hydroelectric power. For a facility like the school, which uses up to 4,000 kilowatt hours a month, that’s more than $1,000 a month in savings. These school savings go to en- hance school programs and classrooms so students can continue to learn in a thriving environment. The plant started supplying power to Atka’s 59 res- idents on December 23, 2012. In the summertime, it also generates some of the power for Atka Pride Seafoods, a seasonal fish processing plant. Saving mon- ey for community members and local industries has grown the local economy and encouraged people to continue residing in Atka. Project Contact Information Owner: City of Atka, P.O Box 47070, Atka AK 99547 Engineers: PolarConsult Alaska, 907-258-2420 Marsh Creek LLC, 907-258-0050 City contact: Julie Dirks, City Administrator Email: dirksjuliea@gmail.com Case Study Author: Zoe Tressel, Alaska Energy Authority Website: Akenergyauthority.org Phone: 907-771-3000 Chuniixsax Creek Hydroelectric Project Completed hydroelectric dam, photo courtesy of AEA. Hydro project construction, photo courtesy of AEA.Published August, 2015