Rather than having the lawmakers viewpoint of imposing higher fuel economy standards on automobiles to solve Americas energy and pollution problems, Willett Kempton has the more exotic approach of turning cars into rolling power stations that can provide clean energy when utilities need it most. Kempton, a 59-year-old renewable energy professor at the University of Delaware, is the foremost proponent of what is considered vehicle-to-grid technology in the U.S. For ten years, Kempton has been attempting to convince automakers and utilities that electric cars could generate power at night, when power is less expensive, and then discharge some of that juice back into the grid during the day to balance supply and demand for electricity. Some car and utility people are starting to cheer Kemptons theory, yet daunting economic and technical obstacles make it a very tough sell. The main stumbling block to producing electric vehicles is the need for cheaper batteries, but Kempton has a way for owners to recoup those costs. His solution involves using cars to supply a reserve of electric power that can smooth out minute-to-minute shortages in the transmission grid. Kemptons plan is one of many proposed schemes to interconnect the nations electric and transportation networks. These plans all take advantage of the fact that energy purchased from a central station power plant is less expensive than energy purchased from a gasoline pump. Kempton insists that there is sufficient economic value for the consumer with his plan, sketching out the economics of an all-electric car. Kemptons group needs to sort out a few thorny issues, and such details could kill the feedback car notion. However, Kempton deserves credit for prompting people to think about creative methods of controlling energy costs.