Airborne wind power

Again pointers from Worldchanging, some interesting projects under development are focusing on airborne wind power. The logic is that the higher up you go, the stronger and steadier the winds become. Sky Windpower plans to put power generators that are lifted into place much like propellors lift helicoptors, and then remain tethered to the ground to send back energy. Magenn plans to put helium blimps into the sky instead. And Laddermill imagines a series of kites strung together, which rotate around a pulley system to drive a turbine.

All the ideas are super interesting, but they can be useful only if translated into practically maintainable systems, which do not crash when storms come, or when the winds go silent.