Wind Power Plants are city improvements in the Power category. They are moderately expensive, and not generally used as a main power source.
Wind Power Plants cost $30,000 and 25 Aluminum to build. They do not use any resources per turn, but do cost $42/turn. This adds up to $500 a day.
Wind Power Plants add 0 points to your Pollution Index.
Wind Power Plants are good supplemental Power Plants. Wind Power Plants are cheap to build and operate, but do not provide for a lot of Infrastructure, making them a drain on Improvement Slots that could otherwise be occupied by different improvements.
Each Wind Power Plant can only power up to 250 Infrastructure levels. Once a city reaches 250.01 or greater Infrastructure it requires at last 2 Wind Power Plants to stay powered.
Wind Power Plants do not require fuel, and will operate as long as you can afford the upkeep cost. When built alongside other Power Plants your city will use Wind Power first, to reduce resource consumption.