AutoblogGreen

Diesels are crap...how is going to a fuel that takes more energy and pollution to produce better?

What a retarded approach the rest of the automakers have...they'll resort to anything to keep hanging on to oil.

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The Diesel Cycle is the most efficient internal combustion cycle at the moment:
If they run at their specific rotation efficiency ratings are two times higher than comparable gasoline motors. So a combination of Diesel and hybrid could bring enormous emission-reduction. The Diesel cycle is much more efficient than the Otto-cycle. The only thing that could be really better for internal combustion is HCCI/Diesotto.

http://en.wikipedia.org/wiki/Diesel_cycle

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This sure is surprising. I'm guessing Toyota has looked at the European market and not really seen a call for diesel hybrid. So, they'll stick to the US, who prefer (generally) gas and allows them to build cheaper engines (for instance, no direct injection). This way, they give people what they want and don't really bother with expensive stuff they can't make profitable. Toyota has just recently started making money with the whole hybrid hocus-pocus, so they'll probably take the spending easy for a while.

Problem is, market is changing really fast right now, and Toyota might lose then train in Europe. Not good when you've just proclaimed yourself the #1 car maker in the world, to lag behind. But I guess they can always catch up with the opposition.

Carlos Ferreira
http://www.greencarvalue.blogspot.com

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This news suprises me as well. Honda and VW are several months to a year away from bringing mainstream clean diesel cars to market, (Accord and Jetta), GM purportedly has some clean diesel cars in the works, there's a coming wave of 1/2 ton pick-ups with diesels in the next few years...just about every week you read of a German nameplate working new variations of diesels in their platforms....then you read this article. You would think with Toyota's deep pockets and technological prowess that making a cost competitive, mass market diesel hybrid would be child's play! I don't understand.

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@armmat, it actually takes less energy but it does pollute more without expensive filters etc.
But I think the real reason is far simpler: Toyota, doesn't have any diesel engines at the moment that would suit a diesel hybrid concept.

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But I don't get it. What makes diesels more expensive? It doesn't seem like it should cost significantly more. Is it just the emissions? Or the engineering for higher-pressure capability? Can't be economies of scale, since Europe and the rest of the world like 'em.

And as long as they are refining oil, diesel is one of the major products of it, so it'll always be useful to have a balance of both types of engines... Even though they should bothe be using MUCH less fuel.

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Diesel is actually less expensive to produce. It takes less refining of oil to produce diesel that gas. The reason that diesel engines are more expensive generally is that they have to be much more robust to deal with the significantly higher compression ratios requires for the diesel cycle. Another expense is the anti-polution requirements that they must meet. Modern diesel engines are actually very clean, but they do produce more NOx emissions than gasoline engines, which is the primary obstical to their adoption in the US.

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The diesel engine operates under enormous pressure. The block, heads, injectors all are more expensive to manufacture due to the higher compression ratios, hence the additional cost of the engines. Diesels also require very expensive "add ons" to make them clean. I think Toyota is looking at the cost and the fact a petrol engine is inherently cleaner. Also at least in the US, diesel is substantially more expensive to buy. My guess is Toyota is probably working on HCCI hybrid engines which should at least match diesel hybrids for mpg, and be cleaner to boot. Or maybe they are to arrogant to think anyone knows more than they do about building cars people want.

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If Toyota's next gen ( plug-in ) synergy drive electric motor can get the car to 45 mph without the help of a gas engine, then the benefit of a diesel becomes significantly smaller factor.

On my daily commute I could keep the next gen prius completely in electric mode. Using gas for the occasional long trip will not me such a benefit.

But, for the Luxury division Lexus, I'd think Toyota should keep the option on the table. I mean if they want to compete.

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It all depends on the drive cycle, how large the advantage of a diesel hybrid over a gasoline hybrid will be. Hybrids are good at reducing part-load waste, which is where diesels excel also. A diesel does cost a few hundred bucks more to build, but the big factor is the $1200 in price premium for the after-treatment.

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Diesel may be less refined, but it physically takes more fuel to make a volumetric unit of diesel than gasoline. You'll also note that diesel fuel weighs more per volumetric unit--this is why.

Toyota isn't saying "no diesels", they're saying "no diesel/electric hybrids". It's true that a hybrid's power delivery doesn't complement gasoline as well, and that diesel powertrains are more expensive (high-strength block and heads, high-pressure injectors, emissions-control and, last but not least, the turbocharger) to make, and would push the price of such a vehicle above what people would pay.

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