Photos: Ford's alternative-fuel vehicles

The electric engine and drive train of an Escape Hybrid. Its battery is housed in the black casing at the rear.

The Escape Hybrid's sealed and encased nickel-metal-hydride (NiMH) battery is stored at the flat-load floor of the cargo area. The regenerative braking system recharges the NiMH battery each time the driver uses the brakes.

The F-150, another Ford vehicle offered with alternative-fuel technology.

Ford claims that its F-250 Super Chief concept, unveiled this month at the North American Auto Show in Detroit, is the world's first vehicle to run on "Tri-Flex" fueling--hydrogen, E85 ethanol or gasoline. The supercharged V-10 is expected to be able to travel 500 miles between fill-ups.

Ford's Reflex concept car, whose diesel-electric engine is designed to deliver 65 miles per gallon.

The Reflex concept car's reverse-butterfly doors are designed to provide easy access and exit.

Ford's Reflex concept car features solar panels in the headlights and taillights that recharge the hybrid-electric battery pack, and solar panels in the roof that power electric fans to cool the interior while the vehicle is parked.