High-Penetration Wind-Diesel Hybrid Power System Pilot Project in Northwest Alaska

Alaska has approximately 250 rural villages that have no link to the central power grids serving the main urban areas. The majority of these villages are served by diesel-driven generators. Because of the extreme remoteness of most of the rural villages, and the lack of roads, the delivered cost of diesel fuel is high, ranging from $.80 to $3.00 per gallon. The high operating and maintenancecosts of diesel generating stations result in electric generation costs that range from $0.15 to $1.00 per kWh. There are also significant environmental hazards associated with diesel power generation, including fuel spills during transport, leaky fuel tanks in the villages, and CO2 and other emissions. To reduce the cost of rural power generation and the environmental impact of diesel fuelusage, the Alaska Department of Community and Regional Affairs - Division of Energy (DCRA/DOE), in collaboration with Kotzebue Electric Association (a rural Alaskan electric utility) and the National Renewable Energy Laboratory, is developing wind-diesel hybrid power technology to be implemented in a pilot project in the village of Deering, Alaska, a native village of 160 people in northwestAlaska. The project will integrate three 65-kW wind turbines into the existing Deering diesel power system (75-kW average load). The system incorporates reactive power and dump load control to provide regulation of line voltage and frequency, enabling the diesel gensets to be shut down during periods of high wind. The system also incorporates short term energy storage to prevent unnecessarydiesel starts and maximize fuel savings. This paper provides an overview of the project and discusses its technical challenges and objectives. Among the technical issues we address are the role of energy storage in high penetration wind-diesel systems and the integration of electric dump loads into municipal facility heating systems to provide additional fuel savings.