This is one is irresistable. From Yale Environment 360:

The U.S. Department of Energy has granted a $43 million loan to a Massachusetts-based company to prove the value of a new technology in which spinning flywheels are used to improve the efficiency of the electric grid. Beacon Power Corp. will build a 20-megawatt flywheel plant in upstate New York in which flywheels spinning up to 16,000 times per minute will act as a sort of short-term power storage system for the state’s electrical distribution system, according to the Associated Press. Essentially, the spinning flywheels would suck excess energy off the electric grid when supply is high, store it in the spinning cores, and return the energy to the grid when demand grows.

Keeping things running smoothly is what oil- and coal-fired plants do well but global warming is putting the kaibosh on carbon-based grids. In an era of the more intermittent solar and wind power, electricity "storage" technologies will be key. And the centuries old flywheel is just the thing. Of course, they won't look like the one above. Beacon's flywheels are "small" at one ton each and spin in sealed chambers, pictured at right. The old ones are a bit more dramatic, but still... Let the steampunks rejoice!

Photo of 19th c flywheel from Wikimedia Commons
Beacon Power flywheel photo credit: the AP/Lisa Poole