For decades, we've been trying to figure out the most efficient way to extract energy from high winds. Hermann Honnef, a German structural engineer, proposed using giant windmills atop skyscrapers to provide cities with cheap electric power. Using the Empire State Building as an example, Honnef designed a two-wheeled, 12-story tower equipped with electric dynamos in the hubs to generate a current. Wheels would have a diameter spanning two city blocks and would rotate seven and a half times per minute, or at 142 miles per hour. According to his calculations, a three-wheeled skyscraper windmill could provide electricity to a city with a population of 100,000.
Read the full story in "Skyscraper Windmills to Harness Air for Power"