Technology Review writes:
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 isnt the hulking machines in the labs museum that capture [Alan] Epsteins enthusiasm. Instead its a jet engine shrunk to about the size of a coat button that sits on the corner of his desk. Its a Lilliputian version of the multiton jet engines that changed air travel, and, he believes, it could be key to powering 21st-century technology.
Though the turbines blades span an area smaller than a dime, they spin at more than a million revolutions per minute and are designed to produce enough electricity to power handheld electronics. In the foreseeable future, Epstein expects, his tiny turbines will serve as a battery replacement, first for soldiers and then for consumers. But he has an even more ambitious vision: that small clusters of the engines could serve as home generating plants, freeing consumers from the power grid, with its occasional black- and brownouts. The technology could be especially useful in poor countries and remote areas that lack extensive and reliable grids for distributing electricity. A comparison to how the continuous shrinkage of the integrated circuit drove the microelectronic revolution is tempting. Just as PCs pushed the computing infrastructure out to users, microengines could push the energy infrastructure of society out to users, says Epstein.
Epsteins immediate goal, however, is to use these miniature engines as a cheap and efficient alternative to batteries for cell phones, digital cameras, PDAs, laptop computers, and other portable electronic devices. The motivation is simple: batteries are heavy and expensive and require frequent recharging. And they dont produce much electricity, for all their size and weight.