It's estimated that in the US alone there's over 225,000km of train tracks criss-crossing the country. So a team of researchers from New York's Stony Brook University has developed a simple railside generator that's able to convert the vibrations from a passing train into usable electricity.
The most difficult part of developing the generator was dealing with the erratic vibrations of a train as it rolled past. Varying cargo from railcar to railcar results in irregular vibrations, which makes it hard to convert those up and down motions into the constant spinning required for a generator. But with specially developed one-way clutches, and the use of a flywheel to smooth things out, it's estimated that the generators could easily produce enough electricity to power track-side machinery like gates, signal lights, and switches. And if New York installed around 10,000 of them, they could cut the state's energy bill by half a million dollars. [Newsday via Gizmag]