This Small Device Harvests Electricity From Exhaust

Every time a gas engine runs, roughly three-quarters of its fuel escapes as heat through the exhaust, completely wasted. Researchers at Pennsylvania State University have built a compact device that clips directly onto vehicle exhaust pipes and converts that lost heat back into usable electricity. The prototype produced 40 watts in laboratory tests, with computer simulations projecting significantly higher outputs under real driving and flight conditions. Unlike earlier thermoelectric systems, it requires no water cooling, making it light enough to fit existing vehicles without major modifications. Military funding supported the research.