Reap the whirlwind

摘要

Whirlwinds are associated with destruction, not sustainable energy. Now it seems we can harness their power to generate renewable electricity. The Sdlar Vortex system is the brainchild of Mark Simpson and Ari Glezer at Georgia Institute of Technology in Atlanta. It relies on the temperature difference between hot air close to the ground and cooler air just a metre or so above it. As the hot air rises and cool air falls, convection currents form between these layers, leading to small whirlwinds or dust devils.