VW Committed to the Cause of Diesel Hybrids?

[TDIMeister]

Committed to the Cause?

 

[kydsid]

I've never been a fan of battery packs. If not I'll take one of those with just a diesel motor, I like the styling.

 

[dubStrom]

Das Auto had Jetta hybrid on the cover

As I recall, the Jetta hybrid is already on the way to the showroom this Fall.

http://forums.tdiclub.com/showthread.php?t=354638

I got the Das Auto issue by mail last month. They claimed it was a done deal... will go on sale (but it is a TSI 1.4L Gasser). The hybrid Jetta looks nice, but as I describe in the post above, they claim 45 combined. I get nearly 40 now with a 2 liter CR TDI. 1.6L CR TDI equipped Jetta would do just as well as the hybrid, much less complicated.

Why the heck don't they just equip North American bound Golf, Beetle, Jetta, Golf Variants with a 1.6L diesel. They should bolt right in, and they all ready make them!

 

[kjclow]

But they have probably never been submitted to the EPA for emmissions approval.

The more I see of the cross coupe, the more I like it. Of course we will probably never see a real one over here.

 

[RNDDUDE]

Regarding the Cross coupe plug -in diesel-electric hybrid.....YES, YES, YES, YES, YES!

 

[handyguy]

Just when I think i'm making fuel efficiency progress, another improvement appears! ( just sold the bigMB gasser and got a TDI sportwagon)

 

[bhtooefr]

Why the heck don't they just equip North American bound Golf, Beetle, Jetta, Golf Variants with a 1.6L diesel. They should bolt right in, and they all ready make them!

Because the EPA would stop them at the border and turn them back unless VW spent millions on certifying it.

 

[No More Buffalo]

While I wouldn't want batteries either, if I could get a Golf that got Prius mileage in town and TDI mileage on the highway, without adding too much weight - for my driving patterns that would make a lot of sense.

 

[kjclow]

That's been my argument for bring the Polo or Golf Bluemotion over. Give us a car that can compete with the prius for mileage without sacrificing the driving performance.

 

[need4speed]

I actually wouldn't care so much how much it weighs, as long as it got Prius mileage in town and TDI mileage on the highway.

When I bought my 03; I had a 80 mile-a-day highway commute. Two years later, I changed jobs, and now I have a 15 mile-a-day commute, and I don't get the 45 mpg. But honestly - I'm still getting way better mileage than my wife's brand-new Toyota Yaris.

Just because the "EPA-rated" MPG number is marginally lower, doesn't mean that the car (platform) isn't competitive. It may be that hybridizing diesel just isn't a good business-case for VW right now, (because the technical benefit isn't worth the costs - as opposed to a platform like the Porsche 918, where you know you can charge your customer $150k, and recoup all your R&D and other startup costs).

From a "social engineering" standpoint, I would much rather see a lot more R&D funding going to large-scale production of (useable) biodiesel, than hybridizing petrodiesel cars. (in addition to some worthwhile battery technologies that can compete in recharge-time and range, for full-electric cars).

 

[No More Buffalo]

Weight matters for mileage though - more mass means more power to accelerate to a given speed, and also more weight on the tires = higher rolling resistance.

 

[bhtooefr]

Weight matters for city mileage, although that's where the hybrid system has the most benefit.

For highway mileage, it's such a tiny part that it doesn't matter - reducing drag, even if it adds weight, is almost always worth it for highway.

 

[v1k1ng01]

If they make it, I will buy it!!!

 

[F8L]

While I wouldn't want batteries either, if I could get a Golf that got Prius mileage in town and TDI mileage on the highway, without adding too much weight - for my driving patterns that would make a lot of sense.

That seems like a do-able goal. The current Prius does just and then some because it offers even better mpg on the highway than the TDI when driven at 70mph and below. Above 70mph I'd give the nod to the TDI (in an aerodynamic body) but just barely. Last week I made a couple trips at 70-75mph with the A/C blasting and still ended the trip at 55mpg. Keep speed at 60mph or lower and 65mpg is possible with those neat hybrid trips like engine cutoff.

I'm happy to see VW venturing down this road. True it's not a diesel but not everyone who wants an efficient car wants a diesel or a Prius. Give em a hybrid VW instead! LOL

 

[tditom]

Thanks for providing the link, 'Meister.

This is a cool idea to drive the rear tires with a separate electric motor.

Also liked the short article on the MB e300 diesel-hybrid. That is a slick design and only adds 220lbs to the car.

 

[VeeDubTDI]

As I recall, the Jetta hybrid is already on the way to the showroom this Fall.

http://forums.tdiclub.com/showthread.php?t=354638

I got the Das Auto issue by mail last month. They claimed it was a done deal... will go on sale (but it is a TSI 1.4L Gasser). The hybrid Jetta looks nice, but as I describe in the post above, they claim 45 combined. I get nearly 40 now with a 2 liter CR TDI. 1.6L CR TDI equipped Jetta would do just as well as the hybrid, much less complicated.

Why the heck don't they just equip North American bound Golf, Beetle, Jetta, Golf Variants with a 1.6L diesel. They should bolt right in, and they all ready make them!

Jetta Hybrid and Touareg Hybrid are both available in showrooms... have been for a little while, at least around here. Haven't seen many/any in the wild yet.

 

[rotarykid]

In a pile of papers somewhere I have a VW "what's new & what's coming" magazine that talks about the late 80s experiment with the normally aspirated 1.6L Ds attached to a electric motor in 100 Golfs. If memory serves it was from 1989.

And on what is actually gained with a hybrid attached to a diesel over just having a small displacement diesel, I'm not seeing it for the all the extra costs involved....

 

[tditom]

In a pile of papers somewhere I have a VW "what's new & what's coming" magazine that talks about the late 80s experiment with the normally aspirated 1.6L Ds attached to a electric motor in 100 Golfs. If memory serves it was from 1989....

Good memory! from the article:

Volkswagen has history with diesel hybrids. In the
late 1980s, the German car maker conducted trials
involving 40 naturally aspirated diesel hybrid Golf
vehicles, only for it to be decided that the cost of
developing such a vehicle for production was too​

high.

 

[rotarykid]

They claim 40??, I recall it being stated as it being 100 cars that got this expermental drivetran....

This has me thinking about looking for that magazine. I have moved 5 times some ~9,000 miles covered over the last 24 years so it might have gotten tossed.....

 

[Daniel L]

as opposed to a platform like the Porsche 918, where you know you can charge your customer $150k, and recoup all your R&D and other startup costs).

Heh, more like $845k

 

[powerfool]

Trains essentially operate like the Chevy Volt, but with a diesel engine. I don't understand why they are going full steam ahead on this... they should be able to shatter the mileage of gas-electric hybrids.

 

[TDIMeister]

It most certainly does not. This is widely mistaken, but the distinction is important. A locomotive uses the electric part of the powertrain merely as a type of continuously variable transmission, transferring the power developed by the Diesel engine to the wheels. This is because friction clutches in a conventional gearbox or the slip and poor efficiency of a torque converter transmission are impractical (although the latter is used in some small Diesel-powered trains). There is no means of storing electrical energy for later use - the very definition of any hybrid - and there is no means for regenerative braking (the traction motors do help in the braking duties by dissipating the kinetic energy in a massive bank of resistors as heat, but once done, it's never recoverable again).

 

[bhtooefr]

The Volt is actually set up a fair bit differently in reality.

A train has a generator head on the engine, powering electric motors. This essentially acts as a gearless transmission.

The Volt's transmission is more similar to the Prius's in concept, although with clutches that the Prius doesn't have.

The planet carrier is locked to the final drive at all times.

The sun gear has the main electric motor.

The ring gear has one clutch to lock it to the case, and another clutch to lock it to the motor/generator. (Only one of these is locked at once.)

The motor/generator has another clutch to lock it to the engine.

So, the motor/generator can be disconnected from the transmission and connected to the engine, for pure generation. Or, it can be connected to the transmission and disconnected from the engine, for regenerative braking. Or, it can be connected to both, and the engine drives the wheels (with the main motor varying its power to set engine RPM at the desired point, I believe).

 

[wolfskin]

I thought the Prius' transmission is actually like what you discribed, and the Volt is a pure series-hybrid, e.g. the IC engine never directly drives the wheels, it just drives the electric generator when required.

Diesel-electric locomotives' transmissions are not actually very energy-efficient, not on par with a pure mechanical dry-clutch tranny. Just that it's the most efficient setup that's techincally feasible.
Trains are very fuel-efficient overall, but that's because of factors not having much to do with the power-train:
- steel tracks and wheels resulting in very low rolling resistance even with huge weights on the weheels.
- few stops and starts, which also allow for very low power-to-weight ratio
- very long form factor, which reduces aerodynamic drag-to-payload ratio

 

[bhtooefr]

http://blogs.cars.com/kickingtires/2010/10/the-great-chevy-volt-hybrid-mishap-explained.html

The Prius transmission is far simpler.

MG1 is connected to the sun gear.
Engine is connected to the planet carrier.
MG2 as well as the final drive are connected to the ring gear.

So, basically, the Prius sets the speed of MG2 to match the desired vehicle speed, then sets the speed of MG1 such that the engine is at the optimum speed for the current load.

No clutches anywhere.

 

[kjclow]

And I thought the dual clutch system on the DSG was complicated! The Volt engines and transmission sound like they have a much greater potential for catastrophic failure.

 

[bhtooefr]

Overall, I'd still say the Volt transmission is simpler than the DSG.

The Volt transmission has:

One planetary gear set
Three clutches, which don't see anywhere near as much slippage as a clutch on a manual or DSG

The DSG has:

Seven dog clutches, and I'd be unsurprised if they're synchronized
Two friction clutches
Computer controlled mechatronics unit handling shifting the gears
Three shafts (IIRC)

 

[kjclow]

Again, I know so little about these cars. Didn't realize how complicated the DSG really was. Maybe I should go trade the JSW for a manual Passat.

 

[waspie]

Overall, I'd still say the Volt transmission is simpler than the DSG.
The Volt transmission has:
One planetary gear set
Three clutches, which don't see anywhere near as much slippage as a clutch on a manual or DSG
The DSG has:
Seven dog clutches, and I'd be unsurprised if they're synchronized
Two friction clutches
Computer controlled mechatronics unit handling shifting the gears
Three shafts (IIRC)

taking time off from posting in autoblog are ya?
i was hoping for pics on the flintstones mobile

 

[bhtooefr]

The manual still has seven dog clutches with synchronizers (those being wear items, although if you're nice to them, they last longer than the life of the car), a friction clutch, and I think even three shafts.

Oh, and a conventional automatic has multiple planetary gear sets, multiple friction clutch packs (I think roughly one per ratio?), a torque converter, a valve body with solenoids, etc., etc. So, really the Volt transmission is pretty simple compared to most modern automated transmissions other than the Power Split Device used in the Toyota and Ford hybrids.

taking time off from posting in autoblog are ya?
i was hoping for pics on the flintstones mobile

The source article over there had a pic...