Cars That Power the Grid

  • Posted 02.17.11
  • NOVA scienceNOW

In the future, your car might indirectly power your refrigerator. Electric cars are becoming more and more common, and engineers are investigating how these vehicles can feed power back to the electric grid. Here, see one "V2G" (vehicle-to-grid) prototype developed by Willett Kempton at the University of Delaware.

Running Time: 02:11


Cars That Power the Grid

Posted: February 17, 2011

NEIL DEGRASSE TYSON: So is the future of driving one where everyone has an electric car?

ERIC LIGHTNER:Yeah, eventually I believe that will be the case.

NEIL DEGRASSE TYSON: An electric car like this?

ERIC LIGHTNER: Well, maybe not one exactly like this Tesla, though.

NARRATOR: In 2006 Tesla came out with their Roadster, a lightning-fast electric sports car, with a pricetag to match. But it wasn't until 2010 that other automakers joined the pack. Nissan came out with the affordable Leaf, and many more electric cars are headed to market. No one knows if these cars will become common, but if they do, they could revolutionize the grid. Professor Willett Kempton at the University of Delaware is developing a really smart electric car that doesn't only take electrons off the grid; it can also give them back.

WILLETT KEMPTON: This control box right here that says V2G on it, vehicle to grid, allows the battery in this vehicle to be used for regulating the power on the electric system.

NARRATOR: The control box is in constant contact with the grid. It can stop charging when the grid is stressed. It can even discharge when the grid needs extra power.

WILLETT KEMPTON: When I use this control system to discharge the battery onto the local electric system, I can run my whole block. I can run twelve houses with all their appliances. A hundred cars like this is equivalent to a one-megawatt power plant.

NARRATOR: These cars can also solve a complex problem, the fickle nature of wind and solar power.

WILLETT KEMPTON: Those are great clean sources of electricity, but the problem is that they fluctuate. Some times there's more than you need sometimes there's not as much.

NARRATOR: When there's more wind or solar power than the grid can use, these intelligent cars know just what to do.

WILLETT KEMPTON: The box responds by telling the battery to charge extra fast when there's excess wind or solar. So it's an easy-to-use storage device it can be used to support renewable energy.


Produced for NOVA by
Terri Randall
Edited by
Jedd Ehrmann
Senior Produced by
Julia Cort
Narrated by
Neil deGrasse Tyson
Animation by
David Margolies
Special Thanks
Tesla Motors

Related Links

  • Smart Grid

    Our electric grid is a marvel of 20th-century engineering, but it's showing signs of strain. Can a "smart grid" help?

  • Toward a Smart Electric Grid

    Should the U.S. be upgrading now to a "smart" electric grid? An energy expert insists there's no time to lose.

  • Car of the Future

    Join the "Car Talk" guys as they hit the road in search of a new breed of clean, fuel-efficient vehicles.

  • Cars That Drive Themselves

    Roboticist Sebastian Thrun shares his excitement about real-world applications for autonomous vehicles.