You know all that gas spitting out the exhaust of your car? Not only is it full of carbon monoxide and other things you shouldn't breathe, it's also full of heat. Heat is wasted energy, and students at Purdue University, led by mechanical engineering professor Xianfan Xu, are working to capture it. With some funding from General Motors the team is working to create better thermoelectric generators, or TEGs, that work at much higher temperatures than those we've seen before
