Three innovative designs show you don’t need a giant turbine to harvest the wind’s energy.
Windmills might be a source of renewable, clean energy, but their design limits them to rural areas with high-speed winds. Shadow-flicker and noise are common complaints of those who have lived near the giant structures, and the possibility of flying ice or a falling tower makes them unthinkable in high-density areas. Luckily, elevated turbines aren’t the only way to catch the power of wind. For Sierra, David Ferris highlights three innovative designs suited for use in different environments.
A 25-square-foot structure designed to sit atop tall buildings, the Vibro-Wind Panel (top) is a great fit for urban areas. To capture energy, foam blocks wobble in the wind. One of the panel’s lead developers, Frank Moon of Cornell University, estimates that in the right conditions the Vibro-Wind Panel could compete with a solar panel of similar size.
Hot and Dry
Still in the concept phase, the Solar Wind Downdraft Tower (right) would create its own wind by spraying mist, delivered by solar-powered pumps, at the top of a 2,200-foot tower. The tower’s height would make the Downdraft the tallest building in America, but the sinking, evaporating mist could create enough wind, once channeled through tunnels and turbines, to power 1.6 million homes.
Perhaps the most versatile of these models, the Sheerwind Invelox (left) gathers wind from any direction, funneling and forcing the air through a turn to accelerate its speed. Finally, the air runs past a turbine, which converts the energy. The Invelox can produce the same amount of power as a commercial wind tower at a third of the height—60 to 90 feet tall—and gather breezes travelling under two miles per hour, far less than the speed required to spin the blades of a giant windmill. Invelox inventor Daryoush Allaei has designed a collapsible model made of aluminum and fabric that can be air-dropped for assembly in disaster areas or military outposts. Of course, a more durable version can be used to supply energy to established buildings and communities as well.