Technology uses auto exhaust heat to create electricity, boost mileage

Researchers are creating a system that harvests heat from an engine's exhaust to generate electricity, reducing a car's fuel consumption. The effort is funded with a $1.4 million, three-year grant from the National Science Foundation and the U.S. Department of Energy. A Purdue University team is collaborating with General Motors, which is developing a prototype using thermoelectric generators, or TEGs, said Xianfan Xu, a Purdue professor of mechanical engineering and electrical and computer engineering. TEGs generate an electric current to charge batteries and power a car's electrical systems, reducing the engine's workload and improving fuel economy. The prototype, to be installed in the exhaust system behind the catalytic converter, will harvest heat from gases that are about 700 degrees Celsius, or nearly 1,300 degrees Fahrenheit, Xu said. Current thermoelectric technology cannot withstand the temperatures inside catalytic converters, where gases are about 1,000 degrees Celsius, he said. However, researchers also are working on new thermoelectrics capable of withstanding such high temperatures, a step that would enable greater fuel savings. The project begins Jan.1. The first prototype aims to reduce fuel consumption by 5 percent, and future systems capable of working at higher temperatures could make possible a 10 percent reduction, said Xu, whose work is based at the Birck Nanotechnology Center in Purdue's Discovery Park. The research team, led by Xu, involves Purdue faculty members Timothy Fisher, a professor of mechanical engineering; Stephen Heister, a professor of aeronautics and astronautics; Timothy Sands, the Basil S. Turner Professor of Engineering, a professor of materials engineering and electrical and computer engineering, and executive vice president for academic affairs and provost; and Yue Wu, an assistant professor of chemical engineering. Fuente: http://www.nanowerk.com/news/newsid=19138.php?utm_source=feedburner&utm_medium=emailutm_campaign=Feed%3A+nanowerk%2FagWB+%28Nanowerk+ Nanotechnology+News%29