Running on waste heat
It’s estimated that more than half of U.S. energy — from vehicles and heavy equipment, for instance — is wasted as heat. Mostly, this waste heat simply escapes into the air. But that’s beginning to change, thanks to thermoelectric innovators such as MIT’s Gang Chen. Thermoelectric materials convert temperature differences into electric voltage. About a decade ago, Chen, the Carl Richard Soderberg Professor of Power Engineering and head of MIT’s Department of Mechanical Engineering, used nanotechnology to restructure and dramatically boost the efficiency of one such material, paving the way for more cost-effective thermoelectric devices. Using this method, GMZ Energy, a company co-founded by Chen and collaborator Zhifeng Ren of the University of Houston, has now created a thermoelectric generator (TEG) — a one-square-inch, quarter-inch-thick module — that turns waste heat emitted by vehicles into electricity to lend those vehicles added power. “Everybody recognizes the great potential of waste heat, but the challenge has always...