Friday, July 25, 2008

More Efficient Thermoelectrics

Turning heat into electricity:

By improving the electronic properties of a common thermoelectric material--a type of semiconductor that converts heat into electricity--researchers have doubled its performance, making it more practical for generating electricity from waste heat such as that produced in power plants and car engines.

Thermoelectrics haven't been widely used to generate electricity because they are expensive and inefficient. To increase the efficiency, the researchers, including Joseph Heremans, a professor of mechanical engineering and physics at Ohio State University, added trace amounts of thallium to lead telluride, a thermoelectric material that's been generating electricity onboard deep space probes for decades. The added thallium doubled the material's ability to convert heat into electricity by increasing the voltage that it produces. Heremans says that the improved efficiency could translate into a 10 percent increase in the fuel economy of cars if the devices are used to replace alternators in automobiles by generating electricity from the heat in exhaust.
How cool is that? Every now and then I read something that almost makes me miss being an engineer.

1 comment:

Shawn said...

...that is cool; and one great example of why I get worried when I see government subsidies for this or that "alternative energy sources" (preaching to the choir, I'm sure). I think...man, if govt. subs. were greater, this guy would never have been trying this, b/c he would have (logically) been chasing the grant money elsewhere. How many brilliant people do we have looking at the wrong problem?