Alaska’s waters are perhaps the state’s largest potential source of renewable energy. Hydroelectric sources currently supply about 24 percent of the state’s electrical energy. In the NANA region, small-scale hydroelectric power plants, with minimal environmental impact, may prove to be economical at sites on the upper tributaries of the Kobuk River. Although power output would be minimal October through March when the rivers ice over, hydropower production would be substantial for the rest of the year. In-stream (hydrokinetic) turbines are an emerging hydroelectric technology which could also find applications in the NANA region’s rivers and streams.