Energy Harvesting Gets Big--And Small.

The article discusses the development of energy harvesting around the world. People have harvested energy since the first water wheel, however, in modern times it is all about scaling. Large scale energy harvesting involves wind turbines which have rotor diameters spanning 160 feet, with the hub 250 feet above ground level. An intriguing development in the engineering of these behemoths is their use of ultracapacitors. On the other hand, the real excitement in early harvesting is on the microscale.