Far away from the glamour of the electric cars starting to appear on US roads, power utilities are working on the nuts and bolts of recharging batteries that could make or break carmakers' investments in the new technology (Sony Vaio VGN-FZ battery) .
The issues the utilities are grappling with are complex, unfamiliar and potentially costly. Decisions must be made, among others, on how, where and at what cost batteries will be recharged. Uniform standards are crucial (Sony VGP-BPS8 battery) .
Collaboration between carmakers, battery manufacturers, privately-operated recharging services, regulators and a slew of other interested parties is essential (Sony VGP-BPL9 battery) .
"There's a lot of education to be done on how to do this and how to do it cost effectively," says Mark Duvall, director of electric transportation at the California-based Electric Power Research Institute . "It's difficult to recover from a bad experience (Sony VGP-BPL11 battery) ."
Some electric cars are already on the road. Tesla Motors, based in Silicon Valley, has sold more than 1,000 of its electric Roadster model, and advertises 15 charging stations in California where the batteries can be replenished (Sony VGP-BPL15 battery) .
BMW's Mini has leased a few hundred experimental electric vehicles in select cities. A battery-powered version of Daimler's Smart minicar made its debut in the US this week. Smart aims to have about 250 on the road in coming months (ASUS Eee PC 1000HE Battery) .
But the real test will start later this year when the first two mass-produced models, General Motors' Chevrolet Volt and Nissan's Leaf , start rolling off assembly lines (Dell Inspiron 6400 battery) .
The Leaf will be an all-electric vehicle with a promised range of about 100 miles. The Volt will run on battery power for up to 40 miles, but drivers can then fall back on an internal-combustion engine until they reach a recharging point (SONY VAIO VGN-FZ4000 Battery) .
Mike Rowand, director of advanced customer technology at Duke Energy, which serves about 4m customers in five south-eastern and mid-western states, compares the arrival of electric cars to the mass electrification of kitchens and laundries in the 1950s, and the advent of air-conditioning in the 1960s and 1970s (Toshiba PA3399U-2BAS Battery) .
Duke has included electric cars in its load projections for the first time this year, though with a high degree of uncertainty.
Mr Rowand estimates that if every Duke-supplied household bought a Volt, the demand would amount to less than a 10 per cent increase in overall electricity demand. "We do not expect to see any large scale impact on our grid for many years", he says. Even so, systems could be strained if cars are plugged in en masse at times of peak electricity demand. Utilities are likely to offer discounted rates to encourage off-peak charging, especially overnight (IBM ThinkPad T40 Battery) .
The utilities and their partners are initially focusing their efforts on homes and workplaces where cars are typically parked for close to 20 hours of every day.
The typical electric car can be recharged overnight by plugging it into a normal 110-volt household power socket. But the process can be substantially accelerated by using 220-volt outlets or even more powerful "fast chargers" (Sony VGN-FZ460E battery) .
Mr Rowand estimates that installation costs, depending on the type of charger, will typically cost between $300 and $1,500.
Access to chargers will be more problematic for apartment dwellers and others without their own driveway or garage.
Thus, Mr Rowand predicts that most electric cars on New York's streets in the early years will be driven by commuters from outside the city, or by users of car-sharing services (SONY VGP-BPS8 battery) .