The motivation is the same that led to the development of hybrids in the first place: heightened fuel economy. This time, though, plug-in proponents are promising 100-miles per gallon, which would greatly reduce America's dependence on foreign oil suppliers. Says Daryl Slusher of Plug-in Partners, "this technology can make a bigger impact more quickly than any other transportation technology that's available or coming anytime soon."
Automakers, though, are reluctant to invest in this change of hybrid interest, with the main difficulty to be a battery that can handle being plugged into the nation's grid system. Ford's VP of environmental and safety engineering Sue Cischke points out such a battery would have to be larger and heavier, affecting the vehicle's mileage. "I'm not saying there's not a future for it," she added, "but it sounds so great -- you plug it in and you go -- and it's a lot more complicated than that." (Pictured are members of CalCars, a group dedicated in developing 100-mph hybrids.)
[Source: Detroit Free Press, Calcars]