Jet engine on a chip -- replace your batteries?

[GAspnes]

http://radio.weblogs.com/0105910/2004/10/19.html#a1000

Today, our handheld devices are powered by batteries, which are heavy and inconvenient. Fuel cells are just arriving on the market as a replacement. But there is a new contender: micro gas turbine engines under development at the MIT. Engineers there shrunk jet engines to the size of a coat button. And their blades which span an area smaller than a dime can spin a million times per minute and produce enough electricity to power your PDA or your cell phone. While there are still a few hurdles to overcome, these micro turbine engines should be operational in two or three years, with commercial products available four years from now. These micro jet engines also have the potential to free soldiers or travelers to carry heavy batteries. The engineers even think their engines on a chip could be used in poor countries to bring electricity there. Read more...

Here is the flashy introduction of the Technology Review article.

Alan Epstein is quick to tell you he's a "jet engine guy" - just in case you haven’t guessed as much from the turbine engine parts strewn around his office or the museum on his lab’s ground floor, which includes a rare example of a 1944 German engine that helped kick off the jet age. For the director of MIT’s Gas Turbine Laboratory, who stands a slightly stooped five foot six, the fascination has to do with raw power. "The engines on a Boeing 747 shove air through at Mach 1 with 120,000 pounds of force," says Epstein. "The engines on three 747s put out as much power as a nuclear power plant."

Gas turbines powered much of 20th-century technology, from commercial and military aircraft to the large gas-fired plants that helped supply U.S. electricity. But these days it isn’t the hulking machines in the lab’s museum that capture Epstein’s enthusiasm. Instead it’s a jet engine shrunk to about the size of a coat button that sits on the corner of his desk. It’s a Lilliputian version of the multiton jet engines that changed air travel, and, he believes, it could be key to powering 21st-century technology.


Of course that annoying 500 degree exhaust stream might be a problem. Perhaps it could double as a cooking device?

[Dogmudgeon]

1. The advantage

They can be much more efficient than "regular-sized" generators, and generate much lower levels of pollutants.

The jet engines on a 747 are much less efficient; jet aircraft are currently a colossal waste of fuel. They're a 60-year-old technology that hasn't been upgraded.

Turbine generators, likewise, are relatively inefficient, old and outdated.

--bkl