The first hybrid vehicle - a vehicle with two power sources - came as a two-door two-seater. The next was a four-door, five-passenger compact.
Soon, hybrid powertrains will be available in sport-utilities, pickup trucks and luxury cars.
Honda introduced the first hybrid, the Insight, in the United States a year ago. In June, the Toyota Prius began arriving in dealerships. Both represent the future of high-mileage, minimally polluting vehicles.
Dodge recently showed the automotive press the Durango sport-utility with a hybrid powertrain. It goes on sale in 2003 and marks the first large hybrid vehicle. Ford plans to produce a hybrid version of the Escape sport-utility that same year.
Hybrids are so named because they get their power from two sources - gasoline engines and electric motors - rather than from a single engine or only batteries. The combination extends fuel economy into the range of 50 to nearly 70 mpg. The EPA recently announced the Insight had the highest fuel economy of any car sold in America, followed by the Toyota Prius.
`THROUGH THE ROAD'
Dodge's hybrid Durango sport-utility has a patented 'through the road' powertrain technology. It gets its power from a 3.9-liter V-6 engine with an automatic transmission that powers the rear wheels and a three-phase AC induction electric motor that drives the front wheels.
The electric motor assists the gasoline engine during acceleration and recaptures energy normally lost during deceleration. DaimlerChrysler engineers claim it provides the power, acceleration and performance of a conventional V-8 engine but increases fuel efficiency by 20 percent, for 18.6 mpg combined city/highway compared with 15.5 mpg for a conventional V-8 Durango.
The Prius is about the size of a Toyota Corolla. It has four doors and can carry five passengers. It derives most of its power from a 1.5-liter, four-cylinder gasoline engine rated at 70 hp, which is tiny compared with a Corolla's 125-hp engine. The Prius also is equipped with a 30-hp electric motor, which gets its power from 38 modules of 7.2-volt nickel-metal-hydride batteries, the same kind used in early cell phones and laptop computers.
The Prius runs on the gasoline engine, on the electric motor or on both. The engine selects the power source or combination that is optimal for fuel economy and adjusts automatically.
The Insight is substantially shorter than a Civic, Honda's next-smallest car, has two seats, two doors and a rear hatch that covers a small cargo bay.
The Insight is made mostly of lightweight aluminum and is shaped like a teardrop, tapered at the back. The top half of each wheel is covered by sheet metal, reminiscent of wheel skirts. The wheel skirts and teardrop shape make it aerodynamic.
The Insight is powered by a 1.0-liter, three-cylinder gasoline engine rated at 67 hp. It also is equipped with a seven-hp electric motor, which derives its energy from 120 D-sized nickel-metal-hydride batteries. The Insight operates on either power source or on a combination. The combination delivers fuel economy of 61 mpg in the city and 68 mpg on the highway.
The Insight comes with a five-speed manual transmission only; an automatic will become available in 2001. The automatic will be like the Prius'. It will be a continuously variable transmission that constantly shifts to optimize performance and fuel economy rather than shifting at fixed points as traditional transmissions do.
Both cars are equipped with high-tech 'regenerative' brakes. They recapture the energy typically lost during braking and store it in the batteries for use by the electric motor.
Ford's newest sport-utility, the Escape, will be offered as a hybrid vehicle in 2003. Ford says the Escape HEV will get 40 mpg in city driving and will earn Super Ultra Low Emission Vehicle status.