21st century technology, no longer ‘in the future’ by Gerry Malloy
- The year 2000 begins a new era in the history of the automobile, and it has nothing to do with change of the millennium. Rather, it is the beginning of the end of internal combustion engine's monopoly as the motive power for cars and trucks. That is not to say the IC engine has no future. Far from it. But its future will be as one part of a broader mix of available powerplants, each serving its own niche. And that future begins now.
- Hybrid Electric Vehicles: - Heralding this new automotive age is the arrival this year of not one but two hybrid-electric vehicles (HEVs) - the “Honda Insight” and “Toyota Prius”. An HEV is, as its name implies, a hybrid. It is powered by both an IC engine and an electric drive motor. How the two work together depends on the design philosophy adopted, and the Insight and Prius represent different approaches in that regard.
- Both vehicles employ a conventional, albeit highly advanced IC engine that is smaller in displacement and power output - and thus more fuel-efficient - than would be fitted if it were the only powerplant. The IC engine drives a generator which either charges a small on-board battery pack or provides power to the motor(s), based on immediate need. The batteries also provide stored energy to the motor when it is required.
- In the case of the Prius, a complex, computer-controlled power-split device permits the wheels to be driven directly by the engine, directly by the electric motor, or by both in varying combinations. Simpler in design, the Insight’s system differs by using the engine as the primary driving source at all times. It does not provide for operation on the electric motor only, but engages it as needed to provide additional power for acceleration or high speed operation. You can think of it as the electric equivalent of an on-demand supercharger.
- Either way, the net results is substantially reduced fuel consumption, with attendant emissions reductions, while maintaining an adequate level of performance. Both vehicles make extensive use of aluminum and other lightweight materials to further enhance their fuel efficiency, and both capture otherwise wasted energy through regenerative braking - using the motor/generator as a retarder and thus recharging the batteries when braking. Because their electrical power is generated on-board, HEVs avoid the range restrictions, and the need for battery recharging from an external source, that render pure electric vehicles impractical.
- The Insight and Prius are the only HEVs available yet (mid-year 2000) but they won’t be alone for long. Most major manufacturers are likely to follow within the next few years, and right behind them will come fuel-cell powered vehicles!
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