Duke Testing Out a Grid-Scale Battery

Duke Energy's latest project, at a Charlotte, N.C. suburb called McAlpine Creek, doesn't look like much on paper. Some 213 solar panels, enough for just a handful of homes, have been deployed in the neighborhood with a few thousand smart meters.

Along with them, though, is a 500 kilowatt zinc-bromide battery, which substantially outweighs the 50KW output of the panels. The battery's advantage is that it can store up solar power throughout the day, releasing it at peak demand times that the sun isn't at its strongest, like dawn and dusk.

The company that made the battery is Premium Power, according to Toronto Star reporter Tyler Cowen, who has been tracking the startup for some time. And since Duke reportedly put $100 million toward the batteries, they're likely in use at other locations, too.

The upshot of the testing will probably be the wide-scale introduction of batteries to our grid. Since Premium and other firms like Boston Power only add a couple cents cost per kilowatt-hour of electricity, they're a more than worthwhile investment for sources like solar or wind.

Those two often leave energy to waste by producing it when it's not needed. Adding in a convenient form of energy storage is thus the next best thing to the discovery of a cheap new form of energy.