Many european cars have or are bringing their diesel engines to america to offer improved economy and performace. BMW for example. However, I have have not seen much discussion regarding combining hybrid and diesel technology. Why not? What am I missing?
Hybrid/diesel -Why not?
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One thought, and I could be completely off base, but could it be because of the delay required to heat glow-plugs before the engine can be started? Maybe diesel engines just shouldn't be turned off and on like the gas engines are during city driving.
JHZR2
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I believe it has to do with the higher amount of energy required to turn the negine over, compared to a ga$$er...
20:1 compression vs. 10:1 compression is a lot of energy.
Arent most UPS trucks diesel??? They get stopped often. Then again, they arent hybrids and may have other design factors to enable this.
Once a diesel is at temperature, there isnt much need for glow plugs. So, for a traffic circuit, where the engine would go on and off, likely there wouldnt be a need to glow, if the engine is hot.
I wonder if some of the newfangled particulate traps, etc. that are necessary for current diesels would have issues with the start/stop cycle... for burnoff, etc.
JMH
20:1 compression vs. 10:1 compression is a lot of energy.
Arent most UPS trucks diesel??? They get stopped often. Then again, they arent hybrids and may have other design factors to enable this.
Once a diesel is at temperature, there isnt much need for glow plugs. So, for a traffic circuit, where the engine would go on and off, likely there wouldnt be a need to glow, if the engine is hot.
I wonder if some of the newfangled particulate traps, etc. that are necessary for current diesels would have issues with the start/stop cycle... for burnoff, etc.
JMH
Originally Posted By: CBDFrontier06
One thought, and I could be completely off base, but could it be because of the delay required to heat glow-plugs before the engine can be started? Maybe diesel engines just shouldn't be turned off and on like the gas engines are during city driving.
There is no reason to do anything extreme with a modern diesel car engine. The glow plug delay on my VW TDI after a 32F night parked outdoors is about 3 seconds. If it has been run in the past hour there is essentially no delay in that weather.
One reason for not using diesels in hybrids is that the hybrid runs the gas engine in a more efficient power range than a non-hybrid does. Diesels don't lose efficiency at low power as badly as gas engines do, so you don't gain as much going from straight diesel to diesel hydrid as you do with a gas to gas hybrid.
Add to that the additional cost of a diesel engine.
50% of all new cars sold in Europe are diesels. They just aren't a problem anymore.
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JMH, that's a good question on the particulate traps.
One thought, and I could be completely off base, but could it be because of the delay required to heat glow-plugs before the engine can be started? Maybe diesel engines just shouldn't be turned off and on like the gas engines are during city driving.
There is no reason to do anything extreme with a modern diesel car engine. The glow plug delay on my VW TDI after a 32F night parked outdoors is about 3 seconds. If it has been run in the past hour there is essentially no delay in that weather.
One reason for not using diesels in hybrids is that the hybrid runs the gas engine in a more efficient power range than a non-hybrid does. Diesels don't lose efficiency at low power as badly as gas engines do, so you don't gain as much going from straight diesel to diesel hydrid as you do with a gas to gas hybrid.
Add to that the additional cost of a diesel engine.
50% of all new cars sold in Europe are diesels. They just aren't a problem anymore.
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JMH, that's a good question on the particulate traps.
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Maybe it would make more sense on a series hybrid where the vehicle is an electric vehicle with a built in generator (Chevy Volt). A diesel version was mentioned for the European market. The Chinese were shown a fuel cell version and we got the gas engine of course. I hope diesels catch on here because I prefer them myself and there isn't much selection currently.
The hybrid buses that GM makes powertrains for are diesel. Not sure exactly how those work however. Cost most likely is the biggest hurdle for now. I think the exhaust needs to be hot enough for all the emissions stuff to work properly as well like someone else mentioned which is why I think the series hybrid would make more sense since the engine won't be going on and off all the time. It would run to charge the batteries up and then stay off for an extended time.
The hybrid buses that GM makes powertrains for are diesel. Not sure exactly how those work however. Cost most likely is the biggest hurdle for now. I think the exhaust needs to be hot enough for all the emissions stuff to work properly as well like someone else mentioned which is why I think the series hybrid would make more sense since the engine won't be going on and off all the time. It would run to charge the batteries up and then stay off for an extended time.
The main reason you haven't seen them is cost. Diesels add $2000+ in cost, a hybrid system at least that. It would be very efficient, but costly.
A number of car manufacturers are working on them, particularly Peugeot.
Remember hybrids/regen brakings is primarily good for city type driving, not highway driving. Diesels are suited for highway driving.
The best combination identified so far is full hybrid + small diesel + 6-speed paddle shift manual clutch.
One issue is that mixed driving (30-45 mph hills or varying traffic)results in OK fuel economy improvements, but not the same as the hybrid alone or the diesel at 60 mph.
It is likely to be the future.
Other ways to do hybrids are series hybrids, where the engine is a generator and the eletric motor drives the wheels all the time. Improvements in mechanical to electrical conversions need to be made to make it worthwhile. Series hybrids tend to do well in stop and go driving, but mixed often results in less efficiency that just a straight mechanical setup.
Plug-in hybrids require batteries that have very long cycle life and very large energy capacities (duration), which is really hard to do currently.
A number of car manufacturers are working on them, particularly Peugeot.
Remember hybrids/regen brakings is primarily good for city type driving, not highway driving. Diesels are suited for highway driving.
The best combination identified so far is full hybrid + small diesel + 6-speed paddle shift manual clutch.
One issue is that mixed driving (30-45 mph hills or varying traffic)results in OK fuel economy improvements, but not the same as the hybrid alone or the diesel at 60 mph.
It is likely to be the future.
Other ways to do hybrids are series hybrids, where the engine is a generator and the eletric motor drives the wheels all the time. Improvements in mechanical to electrical conversions need to be made to make it worthwhile. Series hybrids tend to do well in stop and go driving, but mixed often results in less efficiency that just a straight mechanical setup.
Plug-in hybrids require batteries that have very long cycle life and very large energy capacities (duration), which is really hard to do currently.
Honda has effectively stopped its hybrid development programs. honda will be bringing its lovely new diesel engines to the US market in 2009. they currently have an accord equivalent in europe that gets upwards of 70mpg. why would they need hybrids? as they say, "the juice ain't wort the the squeeze" in putting a hybrid system on a diesel.
70 mpg?
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I think that everyone here (and more importantly automanufacturers) takes the hybrid thing in the wrong direction. It takes very little hp to move a car down the highway at 65mph. Just size your diesel for 150% of that requirement and it can stay running when you come to a stop. You're not WASTING energy then. The electric component should merely provide the added demand on acceleration. You would probably be down to a 25-30hp diesel operating at 100% the entire time it's running. Much simpler in engineering. No warm up issues ..at least no more than one would normally encounter.
Naturally, the mans take the other approach. Now you could run into some issues of where you CAN'T let it run ..and need to. You're not going to leave it running unattended in your garage ..and you can't be there even if it is. But this reduces "issues" down to a relatively low number of challenges instead of all the fancy hoops that they do now. Way too complex an approach.
Naturally, the mans take the other approach. Now you could run into some issues of where you CAN'T let it run ..and need to. You're not going to leave it running unattended in your garage ..and you can't be there even if it is. But this reduces "issues" down to a relatively low number of challenges instead of all the fancy hoops that they do now. Way too complex an approach.
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Interesting disussion. Looks like there is no easy answer. Perhaps we really need to toss the "aircar" into the mix 
How about a hybrid/aircar/diesel??
How about a hybrid/aircar/diesel??Originally Posted By: BarkerMan
70 mpg?
That would be Imperial gallons under ideal conditions.
That would be 58 miles per Queen Ann's Wine Gallon of 1707 AKA US Gallon.
You can do that with a VW Jetta TDI now at about a steady 60 mph. A cafe rating would be lower. Maybe 50 mpg highway.
There is also a Civic diesel in Europe as well as some small Toyota diesels.
70 mpg?
That would be Imperial gallons under ideal conditions.
That would be 58 miles per Queen Ann's Wine Gallon of 1707 AKA US Gallon.
You can do that with a VW Jetta TDI now at about a steady 60 mph. A cafe rating would be lower. Maybe 50 mpg highway.
There is also a Civic diesel in Europe as well as some small Toyota diesels.
Others said that the main problem with diesel engines in NA in general is pollution. Europe's regulations are not as strict.
They said that expesnive filters are required to cleanup gases enough to pass N.American regulations. Keep in mind California is a big chunk of NA market and they have very low limits. Other states are moving in that direction.
So not only do you need a diesel engine but also costly filters. Those costs added on top of other electric components and very expensive batteries gets you well above $30K price tag (guessing).
Volt using a simple gas engine is trying to limit the price to $30K. Of course, Prius is well below that price.
So in theory it sounds great and will probably be sold in Europe and other markets, just not in US.
They said that expesnive filters are required to cleanup gases enough to pass N.American regulations. Keep in mind California is a big chunk of NA market and they have very low limits. Other states are moving in that direction.
So not only do you need a diesel engine but also costly filters. Those costs added on top of other electric components and very expensive batteries gets you well above $30K price tag (guessing).
Volt using a simple gas engine is trying to limit the price to $30K. Of course, Prius is well below that price.
So in theory it sounds great and will probably be sold in Europe and other markets, just not in US.
It's true that the costs of doing this for a car are too great for the small incremental fuel savings over a regular diesel. Large vehicles that make lots of stops and starts do make sense in a diesel hybrid. I saw a hybrid diesel Purolator truck last summer. It started moving in electric mode, then the engine started up a few seconds later. Garbage trucks will be next.
Originally Posted By: oilyriser
It's true that the costs of doing this for a car are too great for the small incremental fuel savings over a regular diesel. Large vehicles that make lots of stops and starts do make sense in a diesel hybrid. I saw a hybrid diesel Purolator truck last summer. It started moving in electric mode, then the engine started up a few seconds later. Garbage trucks will be next.
Excellent point. One of my least favorite strawman/whipping boy arguments against hybrids comes in the form of citing one example in which a hybrid drive will not be particularly beneficial, and then from that, making broad blanket claims to the effect that hybrids don't make sense for anyone, because they cost too much compared to the savings.
No solution works well for all cases, period. If one's operational pattern is a good fit for a hybrid, then they should consider one. If some other solution is better for them, then they should go that way -- pure and simple.
It's true that the costs of doing this for a car are too great for the small incremental fuel savings over a regular diesel. Large vehicles that make lots of stops and starts do make sense in a diesel hybrid. I saw a hybrid diesel Purolator truck last summer. It started moving in electric mode, then the engine started up a few seconds later. Garbage trucks will be next.
Excellent point. One of my least favorite strawman/whipping boy arguments against hybrids comes in the form of citing one example in which a hybrid drive will not be particularly beneficial, and then from that, making broad blanket claims to the effect that hybrids don't make sense for anyone, because they cost too much compared to the savings.
No solution works well for all cases, period. If one's operational pattern is a good fit for a hybrid, then they should consider one. If some other solution is better for them, then they should go that way -- pure and simple.
Originally Posted By: oilyriser
I saw a hybrid diesel Purolator truck last summer. It started moving in electric mode, then the engine started up a few seconds later. Garbage trucks will be next.
Urban and suburban garbage trucks are ideal for hydraulic hybrid systems using a hydraulic accumulator. The big majority of their routes are hard acceleration then fast stop at less than 100 yard intervals and they already have a lot of hydraulics onboard.
I saw a hybrid diesel Purolator truck last summer. It started moving in electric mode, then the engine started up a few seconds later. Garbage trucks will be next.
Urban and suburban garbage trucks are ideal for hydraulic hybrid systems using a hydraulic accumulator. The big majority of their routes are hard acceleration then fast stop at less than 100 yard intervals and they already have a lot of hydraulics onboard.
AND they could use stored hydraulic power to run the compactor, instead of running the motor which is very noisy at high rpm. Electric battery trucks would work if the dump were nearby.
Don't get too excited about any upcoming BMW diesels in the US. This article on dieselforecast.com about the Euro Accord diesel says:
"The i-CTDi scores a 30 percent fuel economy performance over the gasoline version, with 39 city and 63 highway mpg." (I believe those are US gallons.)
In the article on the same website from BMW's announcement of the upcoming 335d coming to the US, BMW says it will get 23/33MPG. That's pretty weak (although the twin turbo 3.0 liter BMW is faster than the 2.2 liter Honda), and it also has a tank for carrying urea which the Honda doesn't need.
"The i-CTDi scores a 30 percent fuel economy performance over the gasoline version, with 39 city and 63 highway mpg." (I believe those are US gallons.)
In the article on the same website from BMW's announcement of the upcoming 335d coming to the US, BMW says it will get 23/33MPG. That's pretty weak (although the twin turbo 3.0 liter BMW is faster than the 2.2 liter Honda), and it also has a tank for carrying urea which the Honda doesn't need.
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Originally Posted By: Tosh
Don't get too excited about any upcoming BMW diesels in the US. This article on dieselforecast.com about the Euro Accord diesel says:
"The i-CTDi scores a 30 percent fuel economy performance over the gasoline version, with 39 city and 63 highway mpg." (I believe those are US gallons.)
In the article on the same website from BMW's announcement of the upcoming 335d coming to the US, BMW says it will get 23/33MPG. That's pretty weak (although the twin turbo 3.0 liter BMW is faster than the 2.2 liter Honda), and it also has a tank for carrying urea which the Honda doesn't need.
Those are UK imperial gallons.33/52 (6-speed manual) for US gallons pretty impressive.
Don't get too excited about any upcoming BMW diesels in the US. This article on dieselforecast.com about the Euro Accord diesel says:
"The i-CTDi scores a 30 percent fuel economy performance over the gasoline version, with 39 city and 63 highway mpg." (I believe those are US gallons.)
In the article on the same website from BMW's announcement of the upcoming 335d coming to the US, BMW says it will get 23/33MPG. That's pretty weak (although the twin turbo 3.0 liter BMW is faster than the 2.2 liter Honda), and it also has a tank for carrying urea which the Honda doesn't need.
Those are UK imperial gallons.33/52 (6-speed manual) for US gallons pretty impressive.
Those were indeed Imperial gallons. Someone should tell dieselforecast.com so they don't get accused of being Honda-biased (like me).
I just can't wait for my 2009 TSX diesel wagon!
I just can't wait for my 2009 TSX diesel wagon!
Well, for all the folks who are predicting the demise of the hybrid after the arrival of the promised "super diesels," consider the result that appeared in the newly out Feb 2008 issue of Car & Driver. In it, they do a short review after some road time in the European Civic turbo-diesel. The car gets great marks for its persuasive torque and resulting good drivability, but it only averaged 33 mpg, C/D observed. See page 30 of the 2/08 issue.
Even when you factor in C&D's enthusiastic driving, if the Civic diesel can only muster 33 mpg, I'm really suspicious of these amazing 50 and 60+ mpgs we're hearing promised for the coming 09 Accord diesel. I realize that TDIs will have, and when they re-appear, probably will beat 33 mpg by a good margin, but still, that number still makes me wonder where the diesels really are going.
Even when you factor in C&D's enthusiastic driving, if the Civic diesel can only muster 33 mpg, I'm really suspicious of these amazing 50 and 60+ mpgs we're hearing promised for the coming 09 Accord diesel. I realize that TDIs will have, and when they re-appear, probably will beat 33 mpg by a good margin, but still, that number still makes me wonder where the diesels really are going.
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