This spring, GE will start selling a line of "smart charging stations," devices that communicate with utilities to optimize charging, for electric vehicles. The technology could be key to ensuring that electric cars don't strain the power grid, and it could cut down on consumer electricity bills. Eventually, because the charging stations could help stabilize the grid, they could allow utilities to rely more on intermittent renewable sources of energy such as solar and wind power.

The GE products come as automakers introduce a new wave of electric vehicles. GM, Nissan and Ford, for example, plan to start selling electric vehicles this year, and others will follow. While other companies already offer electric vehicle chargers, GE's products could be important because they're made to work with the rest of the company's "smart grid" infrastructure, which stretches from the power plant, through the grid, all the way to smart appliances in the home. The company also has close relationships to utilities, which could speed adoption.

Electric cars could eventually have a big impact on electricity use--charging a plug-in vehicle would account for about 30 percent of a typical household's electricity bill, says Michael Kintner-Meyer, a senior research scientist at the Pacific Northwest National Laboratory in Richland, WA. (He helped develop a smart charger for electric vehicles, which PNNL has made available for licensing.) If too many people decide to charge their cars during times of peak electricity use, it could force utilities to use expensive and often dirty "peaking" power plants to meet demand, or even threaten power outages.

Smart chargers could solve this problem. At the simplest level, GE's chargers would let owners program their cars to delay charging until the middle of the night, when demand is low. As more utilities start to use "time-of-day pricing," when they'd charge less for electricity in the middle of the night, for example, this feature could save customers money. But the chargers can also respond to real-time price signals sent by utilities to GE's smart meters, which are now being installed in some homes. These signals would trigger changes in charging, making it possible for electric vehicles to serve as a buffer, smoothing out variations in supply and demand.