A key energy storage technology for the future, which allows for frequency regulation without wasting extra fuel, takes a big step

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"Take an advanced carbon fiber rim, lift it on magnets in a vacuum, spin it at very high speeds and you can store electrical energy."

That's the simple, futuristic description that flywheel maker Beacon Power gives in a short video describing its energy storage technology. If there's excess power on the grid, it can be fed to the flywheels, which speeds up their rotation, and if there's not enough power, energy can be harvested from the flywheels, slowing them down.

While the principles of flywheels have been known for a long time and smaller-scale facilities built, the completion of Beacon Power's 20-megawatt plant on the New York grid is a milestone in energy storage.

The flywheels are a solution to a problem that most people have never heard of: frequency regulation. The grid has to remain in a state of near-perfect balance between generation and loads. But as millions of people turn their lights off and on or wind generations spins up or down, there are times when the power falls a tiny bit beneath the load or vice versa. Then the frequency on the transmission lines drops under or over 60 hertz. Beacon Power says that its flywheel technology will help maintain the frequency, and therefore stability, of the grid.

Utilities used to keep more generating capacity online then necessary to accommodate for the jitter, which is a waste of fuel. Beacon thinks they've got a better solution because they can do the frequency regulation without burning extra fuel. They simply absorb when there is extra electricity and dispense when there isn't enough. And they think that utilities will be willing to pay them handsomely for that service.

"Some storage technologies should be excellent regulation providers because this matches a zero net energy resource with a zero net energy service," a 2004 Oak Ridge National Laboratory report affirmed.

It's an elegant solution and one that the Department of Energy provided a $43 million loan guarantee for, but so far, investors aren't buying it. Beacon's stock remains stuck in the doldrums.

Image: Beacon Power.

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