Under this nuvista kwethluk solar energy (nkse) project, a joint venture between kwethluk, incorporated, the organized village of kwethluk (kwethluk), and nuvista light & electric cooperative, INC.…

Under this nuvista kwethluk solar energy (nkse) project, a joint venture between kwethluk, incorporated, the organized village of kwethluk (kwethluk), and nuvista light & electric cooperative, INC. (nuvista), will integrate an approximately 250-kilowatts (KW) of solar photovoltaic (PV) array into the existing wind-battery-diesel microgrid in kwethluk, AK. The existing microgrid consists of three diesel generator units rated at about 450-KW, 450-KW, and 280-KW, four 100-KW wind turbines, a 200-KW load regulator boiler, 500-KW/670-kilowat hour (KWH) battery energy storage system (bess) system, along with about 30 electric thermal stoves. The solar PV array is estimated to reduce the diesel consumption by about 16,000 gallon/year for a fuel savings of approximately $77,000 a year. The additional solar resource helps the community of kwethluk to reach its goal of reducing diesel consumption of about 50% from the base case number of about 120,000 gallons. The solar array will be strategically placed to balance the current renewable system and maximize the operation of the existing battery energy storage system (bess), allowing kwethluk to optimize the diesel-off times, taking one step closer towards nearly 100% energy independence. The solar production is expected to increase the percentage of community electric load supplied by renewables by about 10%, offsetting approximately 15,500 gallons of diesel fuel at the power plant each year. Specifically, this solar PV system would leverage the existing bess and provide about 900 hours of diesels-off operation each year, reduce wear and extend the life of the diesel engines. Additionally, the solar PV array will also utilize the existing network of residential thermal heating units which function as a secondary load, allowing some portion of excess solar power that would otherwise be curtailed to be converted to heat, further offsetting use of heating oil. Specifically, the 250-KW PV solar array will deliver power to the existing community grid and is expected to generate approximately 263,000-KWH/year. Conservatively, about 175,000-KWH/year of solar generated power would be expected to serve the primary community electric load and roughly 25,000-KWH/year would be expected to serve the secondary load (residential thermal heating units). Additionally, the solar generation is expected to provide about 900 hours of diesels-off operation at the power plant. Taking into consideration the cost of fuel to the utility, the retail cost of fuel to residents and avoided hourly operation and maintenance cost when the diesel generators are turned off, gross annual savings is estimated to be approximately $88,800.