Another day, another award for the Prius, Green Engine of the Year
For the eighth time in the last five years, the powertrain of the Toyota Prius has been recognized by jury of the International Engine of the Year competition as one of the best. This time around Engine Technology International magazine replaced the previous best fuel economy category with Best Green Engine. The change was done to recognize the desired for both reduced fuel consumption and emissions. The Prius engine and hybrid transmission combo achieves tank-to-wheel efficiency of 34 percent compared to 14-15 percent for most internal combustion engines. The Prius has also been rated at 104g/km of CO2 on the European driving cycle. The 76hp 1.5L four cylinder combines with a 67hp electric motor/generator to achieve these results. The points spread from the 65 member jury of automotive journalists from 32 countries was actually pretty close for the top two spots with the Prius getting a narrow victory over BMW's single turbo 2.0L diesel with start/stop capability.
[Source: UkipMe.com, via Toyota Open Road]
Reader Comments (Page 1 of 1)
Throwback 9:36AM (5/09/2008)
Shouldn't this be the green powertrain of the year? The engine alone is nothing special, it is the seamless integration of the powertrain that is impressive.
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armmat 12:48PM (5/09/2008)
Man...34% efficiency. I know that's definitely better than the pathetic inefficiency of a regular system but still...are we really that backward in technology that after 100 years of automotive history and all that money going into has only achieved 34% efficiency at best?
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Whopper 2:13PM (5/09/2008)
Most IC engines will yield between 30% and 35% thermal efficiency when operated around the torque peak. It is idle time and off-torque-peak operation that depresses the efficiency. That 14-15% number is too dependant upon mode of operation to be anything other than a "talking point". An IC engine that is shut down instead of idling and one that could be maintained near torque peak RPM would have to be more efficient than a non-plugin hybrid. Charging a battery via a generator driven by an IC engine and then driving the vehicle through an electric motor simply has to be less efficient. Too many losses through all of the energy conversions must impact overall efficiency.
Armmat, what contribution do you make to technology in order to include yourself as the part of the "we"?
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Kevin Nugent 2:30AM (5/10/2008)
Is that really how the pruis engine looks?
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Chris M 3:23AM (5/10/2008)
Nugent: That is a cutaway model. It shows how it is put together, but the real thing doesn't show the internal parts!
Whopper: The Toyota Hybrid Synergy Drive is able to take advantage of several efficiency improvements, including running the engine near the peak efficiency speed (like you mentioned) with an electronic CVT, regenerative braking, Auto engine shutoff, and Atkinson/Miller cycle engine. These improvements more than compensate for the energy conversion losses, especially since about 60% of the IC engine power is transmitted mechanically to the wheels and avoids conversion losses.
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joe cross 6:38AM (5/10/2008)
The Toyota 1L 67hp engine won its class also.This 3 cyl.engine matches the Prius' 109g/co2 and weighs only 67kg(worlds lightest ICE) .Producing 93 Nm of Torque at 3600 rpm,this engine propels light city cars with aplomb.With composite bodies and lightened systems even Americans could utilize this.
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ajay 3:16PM (2/17/2009)
its supup
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