In November, WinFlex, a wind-power company based in Kiryat Yam, Israel, received one of the most coveted prizes in the GE Ecomagination Challenge for developing a wind-turbine system that uses a light, flexible cloth sheets made out of composite materials as the rotor system for a wind turbine.

FORBES: Inflatable Wind Turbines Pass Laugh Test

The unique rotor design enables a dramatically simpler overall turbine layout resulting in a cost effective and competitive system for a wide range of power ratings, starting with small turbines and scaling up to MW range.

FORBES: Inflatable Wind Turbines Pass Laugh Test

There is another way to build a greener jet engine: by bypassing the turbine to an even greater extent, with an open rotor.

ECONOMIST: Monitor