International Auto Show in Detroit reflect this continued progress toward PNGV goals.

"The remarkable, new, fuel efficient, experimental cars rolled out at the Detroit auto show prove that our partnership with the Big Three auto makers is showing results," said Vice President Al Gore, "and that we can protect our environment and meet challenges such as global warming in a way that creates jobs and strengthens our economy. PNGV's selection of these technologies for focused research brings us one step closer to the next-generation cars that will both meet the needs of American families and help us reduce pollution and protect our environment."

Under PNGV, teams of scientists and engineers from 19 federal government labs have been working with their counterparts at Chrysler, Ford, GM (under their U.S. Council for Automotive Research umbrella organization), automotive suppliers, and universities. The backbone of the Partnership—created to provide significant energy security, environmental and economic benefits to the nation—is a coordinated portfolio of hundreds of research projects underway at government, auto company, supplier and university research facilities.

HYBRID ELECTRIC VEHICLE (HEV) DRIVE

Today, almost every vehicle in the world is powered solely by an internal combustion engine. Hybrid propulsion systems have two power sources on board a vehicle. One (such as a fuel cell, internal combustion engine, or gas turbine) converts fuel into useable energy. The second power source, an electric motor powered by an advanced energy storage device, lowers the demand placed on the first power source.

When the two HEV power sources are arranged in parallel, one or both can be used depending on the situation. The electric motor often can power the HEV alone in city driving or over flat terrain. When the hybrid is accelerating and climbing hills, the two power sources can work together for optimal performance. Another advantage is that the electric motor can operate as a generator to slow or stop the vehicle; this captures energy normally lost during braking and "regenerates" it into electricity for later use.

High-power batteries with either nickel metal hydride or lithium-ion technology are the most promising devices to store this energy for later use in powering the electric motor. Hybrids require advanced high-power batteries that are designed for repetitive discharge and recharge over 10,000 times a year as the HEV accelerates, climbs hills, and slows or stops using the brakes.

DIRECT-INJECTION ENGINES

PNGV researchers believe highly-fuel efficient, direct-injection (DI) engines—where the fuel is injected directly into each engine cylinder—show the



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