Cold climate problems of a micro-hydroelectric development on Crow Creek, Alaska

A micro-scale hydroelectric plant has been proposed for Crow Creek, a mountain stream located in an off-grid area of the Chugach Range near Girdwood, Alaska. The run-of-river plant design has an expected generation capacity of 125 kW, and could power up to thirty homes and displace polluting diesel generation. The cold-climate hydrology and thermal regime of the stream are crucial in the design of hydroelectric plants in sub-Arctic regions. Solutions for intake ice problems discussed include the inducement of ice cover formation, deep submergence of hydraulic intake works, mechanical ice removal, and even trashrack heating. Also discussed are the physical characteristics of penstocks, the burial and insulation of penstocks to prevent ice blockage, and frazil ice problems. The cold-climate problems of the stream will not preclude micro-hydropower development, but the Crow Creek site demands special design considerations and maintenance procedures.