In the quest to supply electricity for millions of future electric cars, engineers have stumbled upon the most unlikely of energy prospects - the car itself.
If that sounds like a bit of tangled logic to you, then you're not alone. The very idea leaves most intelligent people scratching their heads.
Still, the concept is being examined by auto companies, utilities, universities and industry consultants. And many believe the electric car battery could turn out to be one of the most important sources of current for ... well, the electric car battery.
"This is very doable," says David Cole, chairman of the Center for Automotive Research and one of the industry's most respected consultants. "We're still in the early stages because we don't have high-volume battery production yet. But when that occurs, everything will change."
Indeed, if it happens, it could be a game-changer. Proponents of the idea foresee it happening a little bit at a time. In the beginning, they say, electric cars will "talk" to the grid and determine the best times for charging. That way, they'll grab the energy when the utilities have surpluses. Later on, though, monumental changes will kick in. Car batteries will dump energy back onto the grid when utilities need help. People who need energy - possibly even for their electric cars - will draw it through the grid, from cars that don't need it. Ultimately, experts even foresee a day when retired electric car batteries, connected in long strings inside giant warehouses, will supply energy back to the grid when renewable sources aren't producing.
To be sure, not everyone believes in the vision. Some automakers and utility engineers describe the concept as "interesting," but aren't willing to pencil it into their plans. Those engineers want to know if the concept poses a risk to consumers, or to electrical linemen working nearby. They want to know if repeated, two-way cycling would damage the battery and, if it did, who would be responsible for the damage.
"The business case looks good," says Mark Duvall, director of electric transportation for the Electric Power Research Institute (EPRI). "But it's not clear whether we can provide that service from millions of vehicles intended for transportation. This is not a simple problem."
Talking to the Grid
Simple or not, the idea has trickled into the technological mainstream, and it appears to be gaining momentum. Searching the term "vehicle-to-grid" on Google yields about 20 million hits, an extraordinary number by any measure. Moreover, automakers such as Ford Motor Co. are considering the lowest levels of the concept. And utilities have begun to take on vehicle-to-grid investigations, too.
The concept has built favor over the past few years as several market forces have coalesced. The stampede to electric vehicles and hybrids has highlighted the need for more electrical capacity, while a separate move toward renewable energy has left some utility engineers wondering where the power will come from.
The crux of the problem is simple but unappreciated: Wind turbines make energy only when the wind blows; solar cells generate current only when