Technology that could encourage widespread use of plug-in electric vehicles has been licensed by Battelle to AeroVironment Inc. of Monrovia, Calif.

The technology, developed at Pacific Northwest National Laboratory in Richland, tells a vehicle's battery charger when to start and stop charging based on existing conditions on the electrical grid. Battelle operates the national laboratory for the Department of Energy.

Technology that could encourage widespread use of plug-in electric vehicles has been licensed by Battelle to AeroVironment Inc. of Monrovia, Calif.

The technology is designed to prevent negative impacts to the electric grid as plug-in electric vehicles become more widely used, and use of the technology could result in lower costs for car owners.

"If a million owners plug in their vehicles to recharge after work, it could cause a major strain on the grid," said Michael Kintner-Meyer, the PNNL lead engineer on the technology.

The Grid Friendly EV Charger Controller technology developed at PNNL would allow vehicles to be charged when electricity is most available and possibly less expensive.

"Our studies have shown that those who use the technology could save $150 or more a year on their electricity bill, and they could potentially receive rebates for providing shock-absorbing services to the grid operator," Kintner-Meyer said.

AeroVironment will use a portion of the licensed PNNL technology in a new prototype version of its charging systems.

The new charging systems will continuously monitor the grid's alternating current, or AC, frequency and vary the car's charging rate in response. If an unexpected event on the grid causes a rapid drop in the AC frequency, the charging system will act as a grid "shock absorber" and stop charging.

The resulting charging rate flexibility could make it more practical to add to the grid renewable generation, such as solar and wind, that do not steadily generate power.

"Vehicle charging infrastructure is important for the market adoption of electric vehicles and plug-in hybrid electric vehicles," said Dan Ton, DOE program manager of smart grid research and development.

"We need charging stations and we need them to be intelligent in order to work with smart vehicles and smart grid infrastructure to avoid potential strain on the grid and to provide flexible billing transactions for energy purchases and grid services," he said.

An earlier PNNL study found America's existing power grid could meet the needs of about 70 percent of all U.S. light-duty vehicles if battery charging was managed to avoid new peaks in electricity demand.