April 30, 2009 By Blake Harris
Photo: The Smart Charger Controller simplifies electric vehicle recharging and protects the power grid by automatically recharging at times of least stress on the grid.
If we see a shift to large numbers of electric vehicles on the road - certainly likely if electricity is sustainably produced from solar or other non-CO2 producing technologies - this could severely tax electrical grids, even those employing smart grid technology.
Electric vehicles will become widely available starting in 2011. And the current Obama administration supports a goal of one million electric vehicles on the road by 2015.
Electric vehicles will ultimately reduce the nation's dependency on oil. But they must be charged regularly. A past study from the Department of Energy's Pacific Northwest National Laboratory (www.pnl.gov)showed that 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.
To manage such a demand, a new technology, called the Smart Charger Controller, has been developed at the Pacific Northwest National Laboratory that researchers say will allow such electric vehicles to contribute to an even "smarter" grid.
These controllers will allow electric vehicle owners to simply plug in their cars and forget about them, knowing they'll get the cheapest electricity available and won't crash the grid. The controller automatically recharges electric vehicles during times of least cost to the consumer and lower demand for power. Widespread use of these devices could even help advance a smart power grid, according to the researchers.
"If a million owners plug in their vehicles to recharge after work, it could cause a major strain on the grid," said PNNL engineer Michael Kintner-Meyer in a news statement. "The Smart Charger Controller could prevent those peaks in demand from plug-in vehicles and enable our existing grid to be used more evenly."
"Using the device could save up to $150 a year for electric vehicle owners who pay based on when they charge their vehicle," Kintner-Meyer added.
Owners will program the Smart Charger Controller to charge at a specific time of day or night or at a set price point. The controller uses a low-range wireless technology to communicate with the power grid and determine the best and cheapest time to recharge vehicles. By charging vehicles during off-peak times, the controller saves consumers money.
Previous PNNL studies with household appliances show that "smart" technologies also save the grid from brown-outs with little impact to the consumer. Grid Friendly technology inside the Smart Charger Controller senses stress conditions on the grid. When the grid says more power is needed, the controller can temporarily stop charging the vehicle until the stress subsides.
This instant reduction in charging load, multiplied on a large scale with many vehicles, could serve as a shock absorber for the grid. The technology would relieve load instantly and give grid operators time to bring new power generation sources on line to stabilize the grid - a process that usually takes several minutes.