Geneva 2008: No diesel hybrids for Toyota says Watanabe
The Geneva Motor Show this week was riddled with diesel hybrid concepts from several manufacturers including Mercedes-Benz, BMW and Volkswagen. All of those systems seem destined for production in the next couple of years, particularly the VW Golf TDI hybrid. One company that won't be joining that party is Toyota. Speaking to Automotive News at the Geneva Motor Show this week, Toyota President Katsuaki Watanabe said the hybrid pioneer had no plans to introduce any diesel hybrids. At the Detroit Auto Show, Watanabe announced that Toyota would offer a diesel engine in the Sequoia and Tundra in 2010. Toyota already offers a variety of diesels in the European market. However, according to Watanabe, the combination of diesel and hybrid doesn't yield enough of an incremental improvement in efficiency to justify the combined cost premium of both. At this point, the Toyota Hybrid Synergy Drive system is not suitable for use in the big trucks, which is why Toyota is following just the diesel path for now. Toyota USA VP Bob Carter told AutoblogGreen in Chicago that diesel hybrids are technically feasible and they are being developed (along with many other things as part of Toyota's $1million/hour in R&D spending), but Carter also said that the combination is not possible at a marketable cost.
One big difference between what was shown in Geneva and what Toyota currently has available is that the German hybrids were largely less expensive mild hybrids. These systems primarily provide start-stop capability and some electrical power boost. They also reduce parasitic losses by using regenerative braking energy to drive electrical accessories. One other thing should be kept in mind. Toyota Communications VP Irv Miller recently told us, "Flexibility is one of the beauties of Toyota."
[Source: Automotive News, sub. req'd via PickupTruck.com]
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Reader Comments (Page 1 of 1)
sdiori 10:14AM (3/06/2008)
I find it slightly disturbing that Toyota seems to think that all other hybrid systems are inferior to their own...especially ones Toyota is not currently producing. I dunno...i'm just getting a bit weary of other companies making progress w/ their technologies, only for Toyota to offer a sort of unsolicited rebuttal.
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zamafir 10:20AM (3/06/2008)
I had the same reaction until I researched VW's concept and noticed one of their diesel golfs already provides 70mpg without hybrid, so really, he has a point. Why not just sell a tdi golf with the bosche stop/start system, increasing the costs maybe $500 (if that two year old figure, pre economies of scale, is even that high) while offering the benefit of not polluting when at a stop?
Ken Aisin 1:04PM (3/06/2008)
Not surprised, it's just typical Japanese top management head stuck in the sand comments.
I remember when Canon was the only one selling full frame digital SLRs, Nikon was still having its head stuck in the sand with its DX format DSLRs. Nikon top management kept insisting that full frame DSLRs didn't yield enough of an incremental improvement to justify the cost premium. Meanwhile, Canon somehow managed to squeeze out a new full frame model, the Canon 5D, at a ground breaking price, and with exceptional image quality. What a big slap in the Nikon top management's face!!
So, what happens now? Nikon shocked the photographic world this year with its first full frame DSLR at a reasonable price. The new full frame Nikon D3 has been selling like hot cakes around the world. Some predict that it'll probably take a year or two before Nikon production can finally catch up with demands.
Anyway, I wouldn't be surprised to see a Toyota diesel hybrid, which is more affordable and reliable than its German counterparts. I'm pretty sure this will happen one day.
Richard S. 11:37AM (3/06/2008)
But if the Diesel Gof already provides 70MPG as you claim, then wouldn't a hybrid version be even more efficient?
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hashiryu 11:50AM (3/06/2008)
Not with that particular system. With HSD yes, but would you be willing to pay the price?
psarhjinian 12:31PM (3/06/2008)
To clarify: that's 70mpg on the Euro cycle, at highway speeds. On the EPA cycle, it'd be less (remember, the combined Euro figure for the Prius is 65mpg; the EPA combined is lower). And that 70mpg Golf is slower than a Prius.
The point is correct, though. Diesel doesn't benefit as much from adding electric assist, and it already carries a price premium (stronger block, ultra-high-pressure injectors, emissions system, turbocharger). Adding anything more than mild assist, idle-stop and regen-braking will cost a lot and return very little.
By comparison, a small gasoline engine benefits greatly from electric assist. You get all the efficiency of a small gas engine at high RPM/wide open throttle, with the electric engine offsetting the weak-kneed power delivery at low RPM. The Prius, by abstracting the power delivery method from the drive wheels (gas, electric, both, neither), does very well for exactly this reason--it chooses the most efficient way to power the car based on circumstance and derives benefit from it. A diesel doesn't benefit from this level of management, and thusly from the level of abstraction (and cost) of a parallel hybrid.
zamafir 12:38PM (3/06/2008)
It's not my claim, it's fact, just go to vw.co.uk.
And no, it wouldnt, because VW is using the larger displacement TDI in the hybrid, which makes it faster to sixty then the 1.4l which obtains 70mpg without hybrid...
Sam Abuelsamid 12:49PM (3/06/2008)
Zamafir, those mileage numbers are in miles per imperial gallon. Converted to smaller US gallons the Golf BlueMotion still gets a very impressive 61.8mpg. The bluemotion Golf uses the older 1.9L TDI engine which does not meet US emissions standards for NOx. The hybrid uses a 1.2L three cylinder TDI.
Ken Aisin 12:20PM (3/06/2008)
An interesting article on the Toyota Prius.
http://www.wheels.ca/article/2846
But I'd rather have a diesel engine which is efficient for both freeway and city driving. The hybrid system doesn't do much for freeway driving.
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psarhjinian 12:36PM (3/06/2008)
It actually does improve highway, just not as much. The electric assist in the Prius is always active unless the battery is out. If you slow down on the highway, it regenerates, if you accelerate or otherwise increase load, it offsets the work the gas powerplant has to do.
People perpetuate this inaccuracy because it seems like highway mileage isn't affected: it is, but urban driving is affected more.
Have a look at the Camry I4 vs Camry Hybrid. The Hybrid does a fair bit better on the highway (5.7L/100 vs 6.4L/100, by Canadian measure), but it's the city disparity that gets attention (9.5L vs 5.7L).
psarhjinian 12:40PM (3/06/2008)
Actually, what about a diesel/electic hybrid that uses a naturally-aspirated diesel? That would cut down the cost of the diesel powerplant (no turbo, lower compression=cheaper block) and might make more sense mated to an electric engine. It'd be quite the fuel sipper.
It'd also be crushingly slow. I think people forget that the torque of a diesel is really the torque of a turbo. Non-turbo diesels are total dogs.
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John 12:45PM (3/06/2008)
People need to stop comparing Euro cars to models available here in the US. The fuel economy cycle is totally different and the US safety and emissions regulations are much more severe (what works over there doesn't work here). Plus remember many of the vehicles in Europe are A&B segment. In the US, D segment reigns king followed by C segment.
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stang_fan 3:09PM (3/06/2008)
Not being worth the small/ incremental gains in efficiency? Somewhat believeable, but the cost involved to get that small improvement....that part I do believe most consumers would NOT care to pay. Look at the price premium a turbo diesel sells for, compared to a gas version of the Golf/Rabbit/Jetta. Would someone really pay even more for a hybrid diesel, especially considering the hybrid gas vehicles on the market are barely considered a decent investment?
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Joe 3:58PM (3/06/2008)
Toyota has a reputation of saying one thing and doing another. They usually laugh at the competition and then have a change of mind.
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T2 7:01AM (3/07/2008)
The problem using the Toyota HSD with diesels is incompatibility due to the fixed (magnetic) field generator normally referred to as MG1. This generator requires maximum torque input all the way up the power/rpm curve. Modern gasoline engines can provide that. The generator can then provide max current at all times. A diesel engine, in comparison, has a torque peak at 2800rpm beyond which it decays until reaching maximum power. On one turbodiesel I investigated I found that the torque at the top speed of 4200rpm was down 33%.
This means the generated current will be down 33% if you are not to stall out the engine. The repercussion for the electrical side of the equation means the copper loading of the generator, or ampacity as we call it, will not be fully utilised at the very point we need it most. Either that or we can take a risk that peak current at 2800rpm will not end up roasting the stator winding. Of course the prudent designer will probably size up the generator by 33% to avoid this issue.
One of the reasons the design of MG1 results in an exceptionally small machine is because it is not necessary, in this automotive application, to have a continuous type power rating on the generator. Therefore its small size is already at the limit for the expected short term duration of heavy currents that flow during extreme acceleration. For that reason there is probably insufficient latitude regarding its thermal time constant. The prudent designer would probably choose to increase the rotor stack length over and above that which would be required with a gasoline engine of the equivalent power. Naturally you would have to add this cost on to the diesel premium.
T2
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Stu 10:30PM (3/31/2008)
All right. Toyota has no near term plan for diesel hybrid. But how about a Sienna diesel for thos of us who need that format vehicle, for US delivery?
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