The big drive to create a viable alternative-energy future - by Detroit, multinationals such as IBM and BP, and Silicon Valley startups - is well-known. But there's another serious player in this sphere: the U.S. military, and especially DARPA [the Defense Advanced Research Projects Agency]. Created at the height of the Cold War to bolster U.S. military technology following the Soviet Union's Sputnik satellite launch, the agency has a long history of innovation. Most famously, DARPA's researchers first linked together computers at four locations in the early 1960s to form the ARPANET, a computer network for researchers that was the core of what eventually grew into the Internet. Other breakthroughs have helped lead to the commercial development of semiconductors, GPS, and UNIX, the widely used computer operating system. Can DARPA now score another double success by changing how both the military and civilian worlds consume and produce energy? DARPA's first goal is always to magnify the might of the U.S. armed forces. That's why Arlington (Va.)-based DARPA is devoting an estimated $100 million of its $3 billion annual budget to alternative energy. DARPA describes itself as an incubator of long-shot technologies too risky for almost anyone else to take on. The agency operates by issuing challenges to companies that are so tough they are called DARPA-hard." Typically, DARPA requires contractors to come up with solutions that are orders of magnitude superior to current technology. In addition to spurring the development of palm-size fuel cells, DARPA has contracted with companies to miniaturize solar cells that would supplant the need for generators.

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