RateItAll: The Opinion Network

I question this. Have you ever tried to make a fly do anything? Trying to make a fly push a wheel sounds like more trouble than it is worth.

Great for energy storage; except in catastrophic failure!

These little beauties are just about ready to take the stage. In limited use for the past 100-odd years (as the main component in the potter's wheel, actuators in punch presses, etc.), flywheels have graduated into high-tech applications involving vacuum-sealed semiconductors, carbon-fiber nanotechnology, and state-of-the-art power electronics capable of providing instant power gains from low-level starting sources. There'll come a time when every residence and business will be retrofitted with these things (powered by a solar/wind combination) to capture self-sustaining electricity that requires little or no maintenance (most manufacturers offer 20-year warranties). The real promise might be in on-board chargers for electric automobiles. TRW is working on a solar-fed miniature array that can hook into a generator (the size of a football) that puts out 50 horsepower (string a series of 'em together, and you'll have a fairly powerful vehicle). Component failure remains a worry (which is why flywheels are primarily situated in underground bunkers; auto engineers are experimenting with a foam that can flood a wheel chamber in microseconds to stop destruction stemming from collisions). Expensive now (a 35 kwH model will set you back around 30 grand), but mass production will take care of that. Expect to see them used in massive columned underwater grids on oceanic flotillas powered by sun, wave, and wind. Who would've thought we'd be looking backwards in order to go forward?