"These are not merely temporary solutions that Toyota has selected for the Prius. These technologies, and Toyota’s command of them, will shape the future of the automobile."
Since the 19th century, automakers have used an internal combustion engine as the sole source of vehicle power. But the pursuit of ever greener technologies has forced a re-examination of this basic rule. What Toyota researchers have found is that the combination of a battery-driven electric motor with an internal combustion engine can be up to twice as efficient as an engine operating alone. This flexibility means that hybrids will play a major role in the development of future powertrains.
"Hybrid technology actually expands the potential of the internal combustion engine," expounds
Managing Director Hiroyuki Watanabe, head of Toyota’s EV, Hybrid and Fuel Cell Vehicle development. "Any type of engine could potentially be coupled with a battery and electric motor for significant fuel efficiency gains—gasoline, diesel, compressed natural gas, fuel cells...anything!"
Toyota engineers had to reimagine the role of internal combustion engines in order to meet the bold challenge of doubling passenger-car fuel economy. Whereas traditional engines use a range of gears to efficiently supply motive force, the Prius’ engine operates in a single high-efficiency gear. If excess power is needed, the battery supplies it. If too much power is produced, excess is stored in the vehicle's batteries. Because the Prius manages energy so carefully—and wastes nothing—it can achieve new heights of fuel economy.
Toyota Managing Director
Hiroyuki Watanabe
Greener Thinking for a New Automotive Age