jharlan 10:06AM (5/08/2009):

> Come on you diesel haters

There is nothing to hate here. It's just an inferior, unnecessary design.

Besides paying the price premium for the hybrid part of the drivetrain, you also have to pay the second premium for the much more complex ICE part.


When compared to a gas hybrid, this car has:

- heavier and more expensive engine block and driveline components

- a wearable clutch, maybe even double one with hydraulic actuation

- a gearbox, likely a modern complex and expensive one like one of those automated manual (the electric motor drives rear wheels so there must be a clutch and a gearbox)

- an ultra high pressure fragile fuel delivery and injection system

- variable vane turbocharging, likely twin turbo

- an intercooler

- a particulate filter

- a NOx trap/AdBlue storage and injection system

All of these above need to be paid by the customer. The question is then - what for? This money are much better spent on a bigger battery in an ordinary hybrid with plug-in option. At the start some 20 miles of all electric range are fairly enough in stepwise introduction of PHEVs. Makes you save about 40% of fuel consumed by already fuel sipping hybrid.

Sorry. Diesel hybrids are just a waste of time.

The next funny thing is this car preliminary performance and economy. It's a big SUV that has the 200HP base diesel engine, returns 120 gCO2/km and does 0-60 in 9.4 sec. Problem is, the currently EXISTING Lexus RX450h is also a big SUV, has 300HP base gasoline engine, returns 148 gCO2/km and does 0-60 in 7.5 sec. So the more efficient version of a RX hybrid would likely perform just at the same level as the diesel hybrid without all the additional unnecessary gear. Yet another proof this Citroen makes no sense.

The big secret to this performance parity of diesel and gasoline hybrids is the Atkinson cycle used in the latter. Its peak thermal efficiency is 37% and holds at slightly lower level for most of the time. Torque blender CVT simulating single planetary gearset makes sure the engine stays in optimal range for as long as possible.

Meanwhile modern diesels, for the sake of being compliant with emission regulations, had to drop some compression ratio and stay at about 40% of peak thermal efficiency. Add some heavier gear to haul around and you get observed fuel economy as in case of gas hybrids.


At the end, I need to point out the article in Times Online was written by a perfect example of a genuine ignorant who has absolutely no clue about what he's talking about and knows nothing about motoring.

Some quotes:


Andrew Frankel:

> "So why has no one thought to make a diesel hybrid before?
> The answer has nothing to do with technology and everything
> to do with marketing. Both the Prius and the Insight sell most in
> North America and Japan, places where you will drive for many
> miles before you see a diesel fuel pump"

No, my dear uneducated one. The true reasons are:
- nearly doubled additional cost of the diesel-hybrid setup
- no gain in observed efficiency due to gas-hybrid Atkinson cycle and heavier diesel gear
- stringent emission regulations
- price of diesel on par with RUG in the U.S. The diesel wave in Europe started when diesel fuel was massively cheaper than RUG in the EU (due to lower tax). Now prices are on par, gasoline engines improved (direct injection, turbocharging) and diesel market penetration stops. Meanwhile, Europeans consume more energy producing diesel that RUG because of striking their refineries out of balance. Well done.


Andrew Frankel:

> The Hypnos differs from existing hybrids not just
> in the fuel it uses. Cars such as the Prius and the
> Insight blend the operation of the normal engine
> and electric motor through the same set of wheels.
> In the Hypnos, the diesel engine drives the front wheels
> while the electric motor powers those at the back.
> This not only has a pleasing (and cheap-to-produce) simplicity

Long live inability of any logical reasoning, right, Andrew?

This means that the Hypnos needs a clutch and an automatic gearbox instead of a rudimentary simple torque blending single planetary gearset as in Hybrid Synergy Drive.

Obviously, the added complexity of the modern diesel is completely forgotten. Maybe the author does not even know what an engine is?


Andrew Frankel:

> The first thing you notice is that because diesel
> engines tend to have more torque at low revs the
> car feels eager at the point at which the power source
> switches from the electric motor. In petrol hybrids there
> tends to be a delay while the engine builds up revs after
> the switchover.

Which is perfectly confirmed by reviewers driving gas hybrids and saying that moments of drivetrain power source shifting are imperceptible, right? Like in case of the 2010 Ford Fusion, claimed to be even smoother than the Lexus LS600h.


Andrew Frankel:

> So it has fallen to a European car company to combine
> the two and create a hybrid that will boast a fuel economy
> and emissions level that previous hybrids aspired to but never
> achieved.

Funny are those desperate British journalists defending their heritage (British if possible, European if the British part has gone bankrupt or has been sold to Indians) at the price of writing any nonsense. Not only the car does not exist, its prototype appears to be on par with heavy Lexus RX450h hybrid when performance difference is taken into account.

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wow. that was the LONGEST post I've ever seen, and I am a very, very patient reader. and at the end of it all, you're still so full of your own pompousness and pretense that you fail to notice MASSIVE holes in your argument.

FAIL.

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~D. 11:18AM (5/08/2009):

> at the end of it all, you're still so full of your own pompousness
> and pretense

I'm not about emotions or opinions or liking or taste. Discussing that is just a waste of time and web space.


> that you fail to notice MASSIVE holes in your argument.

Which you accidentally failed to point out and debunk. Only added the word MASSIVE to make your void and vain "response" appear less void and vain.

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"to mock and rage is gentlemanly, to whine and complain is not." -Lampedusa

Referring to my post is "void and vain" after asserting that "I'm not about emotions or opinions... that is just a waste of time and web space" proves that you are a hypocrite and proves that you are passive aggressive in your arguments; you attack others ad homenim with an air of elite fart-huffing smugness, but can't handle honest criticism similarly dished out by others, preferring to write paragraphs of bombast as if space guarantees truth. Some of the most axiomatic truths are elegantly simple to explain. In short, your conclusions and attestations are just plain wrong, as in the opposite of true, so little proof is necessary when you yourself failed to produce any evidence to back up your ridiculous claims.

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downtoearth: so much text, so little thought.

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Actually, I agree that the add'l expense of a diesel-hybrid probably isn't worth it.

Instead, just stick with a turbodiesel engine and forgo the much more expensive hybrid parts.

A traction battery, power electronics, electric motor are much more expensive than simply substituting a turbodiesel + aftertreatment for a gasoline ICE.

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It all depends on how much you drive and the future fuel prices. If you drive a lot of miles these hybrid and diesel hybrids probably would make economic sense. If you are a 10k mile per year guy the only justification for paying the extra money is that you want one. In the end, most people buy what they want instead of what they need.

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I would love to see this in an SUV. Not only could you reap the mileage benefits when just driving around in daily life, your vehicle could actually server the SUV/towing capacity that it is (hopefully) built for. Definitely not the everyperson vehicle, but for those of us who need an SUV type vehicle this could be a win/win.

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