Toyota to sell diesel hybrid by 2010 thanks to Isuzu

AutoblogGreen has reason to be happy, having found evidence that Toyota's recent purchase of a 5.9% stake in Isuzu will bear fruit in 2010 when the Japanese juggernaut marries its Synergy hybrid drive system with a diesel engine. Presumably such a hook up was made possible, or at least hastened, by the expertise in diesels that Isuzu brings to the table. Toyota knows its way around an oil burner too, but its Hino commercial truck division usually deals with diesels meant for trucks and buses.

Heck, even we have to admit that we're excited for such a combo, as diesel engines excel in efficiency when cruising at highway speeds, much more so than a gasoline engine, which to this point has always been the electric motor's dance partner in modern hybrids. JapanToday is reporting that a Toyota subcompact with this diesel hybrid drivetrain will be available as soon as 2010. Assuming we're not all driving EVs by then, such a car should easily grab the mpg crown in the U.S.

Rest In Peace, old friend, your work is finished.......

If you want on or off the DIESEL "KNOCK" LIST just FReepmail me........

This is a fairly HIGH VOLUME ping list on some days......

One of the "drawbacks" for me, with current hybrids, is that they dont get that great of mileage on the highway. The reason is obvious, but still, I expect my highway mileage to be significantly greater than my city mileage in the car I am driving. A small diesel engine would be superb on the highway, and suck in the city, but with the electric motors providing a boost, it could be the best of both worlds.

"One of the "drawbacks" for me, with current hybrids, is that they dont get that great of mileage on the highway. The reason is obvious, but still, I expect my highway mileage to be significantly greater than my city mileage in the car I am driving. A small diesel engine would be superb on the highway, and suck in the city, but with the electric motors providing a boost, it could be the best of both worlds."

Thanks for helping us to understand the excitement here.

A "hybrid" drivetrain (ie, replacing the transmission and gear-based drivetrain with the generator->battery->motors of a hybrid) would allow a diesel to enjoy very, very high efficiency.

Most people, even those who drive diesel cars and pickups, don't know that most all diesel engines have a "sweet spot" in their RPM range where the fuel consumption for the HP generated reaches a minimum. For most "medium-speed" (ie, 600 to 2800 RPM) diesels, this occurs somewhere between 1700 and 1900 RPM. When the engine is turning too slowly, the fuel consumption per HP generated goes up, and when you're running too fast, the fuel consumed per HP generated goes up (quickly).

Diesel engines are usually rated in the US in terms of "HP-hr/gal" -- ie, how many HP can be produced for one hour per gallon of fuel. A really goof number would be over 20 HP per hour on a gallon of standard #2 fuel. A really good number would be anything in excess of about 24 HP-hr/gal.

Until the EPA stepped in and started with their "Tier II" and "Tier III" crap, some farm tractors were exceeding 20 HP-hr in the late 90's. Thanks to the injection timing changes forced on the manufactures in the single-minded quest to get the NOx emissions minimized, we're seeing a decrease, not an increase, in modern ag equipment diesel efficiency. If you're willing to tell the EPA to shove it, you can punch in a chip that re-tunes the injection timing back closer to TDC and you see your fuel consumption go back down to where the engine wants it to be.

Most people, even those who drive diesel cars and pickups, don't know that most all diesel engines have a "sweet spot" in their RPM range where the fuel consumption for the HP generated reaches a minimum.

Same for a gasoline engine, but for a diesel, there is no "pumping loss", so steady state, relatively low RPMs gets you great mileage.

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