Car giant Ford says its future electric vehicles will "talk" to power grids across America, allowing owners to control when they charge them and for how long.

The nation's second-largest car maker released details of a two-year collaboration with 10 utility companies and the Department of Energy on the design of a system it hopes will drive greater interest in alternative energy vehicles.

Ford's first battery electric vehicle, the Transit Connect commercial van, will be available in the US next year. A battery electric Ford Focus will go on sale in 2011.

"At the end of the day this has to be easy for our customer," said Ford chairman Bill Ford.

"This can't just be an interesting science experiment. This has to be something that makes people's lives better and easier and that is what our dialogue is all about."

Utility companies say their grids are already ready to handle electric cars, although some drivers are likely to need additional equipment installed in their garages, depending on the vehicle's voltage requirement.

"The grid is ready now but on a lower technology basis," said Mike Ligett, director of emerging technology at Progress Energy, a company based in Raleigh, North Carolina.

"We are not concerned about energy consumption, but more about when it's used."

General Motors will release its Chevrolet Volt next year, a rechargeable electric vehicle the company says will get up to 230mpg. The Volt, unlike Ford's Transit Connect, contains an internal combustion engine which kicks in after driving about 40 miles.

The Transit Connect will not have a combustion engine and the number of miles a user can drive will be determined by the size of the battery Ford installs in the car, company officials say. Specifics on the vehicle's driving range and price have not been released.

Ford said it was working to build connectivity between its electric vehicles and local power grids in certain areas so owners could choose to recharge at off-peak times when electricity was cheaper, or when wind, solar or renewable energy was driving the grid.

Ford and the utility companies are testing the system and have logged 75,000 miles on a test fleet. The goal is to have a network in place so drivers can recharge their cars at preset times at home, work or elsewhere.

The system aims to develop technical standards so that a car purchased and used in Michigan, can "talk" to an electric grid in New York if the driver moves or travels.