Heat scavenging
余热利用
Stealing the heat
偷点热量
Energy: The idea of recycling paper, glass, metal and plastics has become commonplace. New technologies allow heat to be recycled, too
能源：纸张、玻璃、金属和塑料的回收利用已很普遍。利用新技术也能回收热量
Mar 4th 2010 | From The Economist print edition
“WATER, water everywhere, nor any drop to drink,” lamented the becalmed Ancient Mariner. Oddly, the same is true of energy. As with the water that surrounds a desert island, there is abundant energy right under people’s noses, in the form of wind, sun, tides and heat. The trouble is that, like saltwater, none of these sources is easily tapped. Wind turbines, solar panels and devices that extract energy from wave and tide have become more common in recent years. But technologists have been slower to exploit the vast amounts of ambient heat available in the atmosphere, or produced by machinery.