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Hybrid Diesels?
Are they in our future? How will they perform? What will the emission factors be?
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You said At present, diesels in the USA are merely another example of vehicles which offer improved fuel economy at the expense of performance
The new mercedes CDI is also another example. Better performance and much better fuel economy than the gas counterpart.
I think the current breed of Hybrids sacrifice more performance for the sake of fuel economy than the current diesels. So far the Prius is slower and more expensive than a TDI. Mileage depends on who you're talking to. We'll see what happens with the next round of V6 Hybrids, but I suspect a diesel hybrid would give similar/better performance and better mpg.
Saying that fuel economy is "pointless" in a 58K vechicle assumes that only cost is a factor, which is VERY not true. I care a lot about fuel economy for many reasons, environment, dependence, politics, and a future when the oil runs out. I am of the opinion that people are not going to give up size and power until the oil coming out of the ground slows to a trickle, so we need to find ways to provide that while preserving our resources as best we can.
dave
Dennis
Well, how about to see where hybrid diesel stand against hybrid gas? You sound like a sore person from looking at your other posts. I don't want to ruin this thread because there are so much to discuss regarding how much benefit diesel can get if combined with electric vs. gas electric. If it is not welcome here then, have a great discussion in this thread.
Dennis
:-)
There's a pretty good reason there hasn't been as many hybrid diesel cars produced. The gains to be had are less. Diesels are already throttle-free and lean-burn, so for one thing moving from a 2.0L to a 3.0L doesn't hurt efficiency as much as with a gas engine, and a smaller lean-burn engine is one of the reasons for moving to a hybrid.
Of course, there's regenerative braking and other efficiencies to be had but with the GrandSport, the hybrid makes the diesel 20% more efficient, which is not the same gain as a gas engine gets ( although the net efficiency is still higher ).
There have been some diesel-electric prototypes, but I wouldn’t bet against seeing a production diesel-electric car soon. It might come from Honda of all places. The limiting factor may be the bulk of diesel engines themselves.
If Honda installs an electric motor, twice as powerful as that in the Civic Hybrid (30 HP @ 2500 to 4000 rpm, 75 lb.-ft @ 1000-2500 rpm), to go with its 2.2-liter CTD-I engine current used in European Accord (140 HP @ 4000 rpm, 245 lb.-ft @ 2000 rpm), the power train would deliver 170 HP / 310+ lb.-ft, while improving upon the mileage that the CTD-I already does (rated 52 mpg mixed driving in UK) and definitely improving emissions (smog/green house) with the added benefits of idle stop and regenerative braking etc.
Sure, it would be possible to add displacement to the 2.2-liter engine to get that kind of power, but in the process, emissions will go up, and mileage will go down. And then, another aspect that electric power brings is replacing the current mechanical AWD system (while adding power). That’s an area I want to see hybrids touch in a big way.
Lotus had plans of creating a sports car using diesel-electric hybrid power train, not sure if they are going with it or not.
Just need a battery bank to store the kinetic energy when you have to stop faster than coasting gradually.
"Consumer-based tax credits will play a critical role in gaining market acceptance by making these technologies more affordable."
This is to offset the thousands of dollars more per vehicle cost for consumer vehicles.
What are the tax credits now on the hybrids?
http://www.gm.com/company/gmability/adv_tech/300_hybrids/hyb_time- - line.html
Seattle hopes they will save 700,000 gallons of diesel fuel a year. (a fleet of 250 buses, if i remember right)
This is still to be seen, but it is true that the most efficient hybrids are diesel-electrics. And not just buses, cars and light trucks.
http://tinyurl.com/3f7sa
So can a gas engine with different(Atkinson) cycle. Diesel engines are heavier and more expensive than gas engines. Stop/restart of diesel engine during stop-and-idle-and-go traffic would be difficult due to the heavy engine and the lack of spark plug.
For those reasons, Atkinson cycle gas engine makes more economical and engineering sense. Diesel would be a very good choice thought, just not the best choice.
Dennis
The main difference between "regular" Otto cycle and Atkinson cycle is difference in timing of closing intake and exhaust valves. Pretty much like VVT-i or VTEC.
Prius has been on the road for 7 years, since 1997. It is a Toyota and even Lexus is going to use it. By looking at reliability records of both companies, I wouldn't say the cars that they build are not "tried and true".
Dennis
The way PSD is set up, as long as Atkinson cycle ICE is moving, electricity is being generated. The battery isn't necessary for spark plug to ignite.
"And there is very little to be gained by stopping and starting the diesel"
Yup, that's why diesel and electric hybrid have overlapping benefits but both increase price. That's when "price for benefits" comes into question.
Dennis
I've heard that LAME argument many times now.
It has no basis in reality, since there is no data to support it. The data actually shows that diesel engines suffer in low-idle conditions (like everyday commute traffic)... compared to not running a gas engine at all, like what Prius does.
JOHN
JOHN
I've heard that LAME argument many times now.
It has no basis in reality, since there is no data to support it.
Huh? What's lame about it? A diesel uses very little fuel when idling, that's a fact. Would it be worth implementing features that turn the diesel engine off? Maybe, maybe not that would have to be determined.
I actually did some testing yesterday with my VAGCOM software. I logged and monitored rpms, speed, throttle demand, and fuel qty. I haven't had a chance to really look at the data yet, but I'm trying to compare speeds vs fuel burn to see if there's a sweat spot in the TDI. (is 75mph vs 80mph exponentially worse than 70mph vs 75mph, etc).
At idle here are fuel burn levels:
Idling in neutral no accessories: .5 L/hour (.1321 gallons/hour)
Idling in neutral with A/C: .9 L/hour (.2378 gallons/hour)
I basically can idle with the A/C running for over 60 hours on a full tank of fuel.
That's what would have to be determined. If it costs $1,000 to add this to a diesel, is there really benefits in the end? Maybe, maybe not as I stated above. Worst case, say I commute 300 days a year and am stuck idling 1/2 hour per day. I'd burn an extra 36 gallons per year. That'd take 15 years to recoup the savings, and according to John vehicles don't last half that long anyway, lol. Of course someone like myself, I drive 80-100 miles per day and rarely idle.
Your use of "little" is vague & misleading.
It's like saying a small amount of poison will kill you less than a large amount.
> Idling in neutral
In the real world, people have the heater and lights and the radio on. And in commute traffic they typically crawl very very slowly, rather than just sitting at a dead stop. At a stoplight, shutting off the engine entirely will obviously save fuel.
That "little" you elude to amounts to *MASSIVE* levels of waste when you multiple it times the over 500 MILLION vehicles currently on the road.
JOHN
So you agree the auto stop/start will do very little for a diesel. A battery assist obviously would. Sitting at a dead stop, the diesel is already using much less fuel than a gas counterpart. While coasting the diesel is using zero fuel. Which leaves us with the question of whether or not an auto start/stop would make sense (or cents).
That "little" you elude to amounts to *MASSIVE* levels of waste when you multiple it times the over 500 MILLION vehicles currently on the road.
The vast majority of which are gasoline powered and chugging fuel at a rate greater than a diesel. Please stay on-topic.
Huh? I've been talking about full hybrids all along. You know, the kind that drive using only electricity at times.
I'm not the one that abruptly changed the topic to "auto stop/start", nor have I focused on idle only. In fact, you are the one that mentioned "gas counterpart".
Please stay on-topic.
JOHN
So, do you agree that diesel will get less benefits by going hybrid?
"I actually did some testing yesterday with my VAGCOM software. I logged and monitored rpms, speed, throttle demand, and fuel qty....but I'm trying to compare speeds vs fuel burn to see if there's a sweat spot in the TDI."
Wouldn't it be awesome if a computer knows all those information about your car and optimize everything for you on-the-fly? That will save a lot of work for you, isn't it? Can you say, HSD?
Dennis
Nope. Gas electric use zero fuel at dead idle stop.
"While coasting the diesel is using zero fuel."
Gas electric hybrids don't use more fuel than necessary at all situations.
"The vast majority of which are gasoline powered and chugging fuel at a rate greater than a diesel. Please stay on-topic."
Again, comparing diesel to gasoline cars(off topic). If you want to talk about diesel-electric hybrids, compare it with gas-electirc hybrids.
"Which leaves us with the question of whether or not an auto start/stop would make sense (or cents). "
I would say no because it depends on how long the idling period is. Since, it is unpredictable, it isn't a solution. Diesel in general is a very good application for trucks and buses that operate most of the days and nights. For passenger vehicles, gas-electric hybrids are a better solution.
Dennis
I agree, my question is where the break will occur? From my perspective the GM hybrid PU will be a failure. The Hybrid SUV's on the horizon may or may not share in the success of the Prius. I would have to get 25-30 MPG in a Suburban size vehicle to consider changing.
I think the auto start/stop will have less benefit, particularly if it adds substantially to the cost. The diesel is more efficient to begin with therefore more difficult to justify expensive nuts and bolts.
Wouldn't it be awesome if a computer knows all those information about your car and optimize everything for you on-the-fly? That will save a lot of work for you, isn't it? Can you say, HSD?
Sure, no doubt. Lets just fire it with diesel instead of gas.
Not quite. It's clear to this point what the advantages of running a gas-electric are. When starting out with a motor more efficient than a gas motor, the advantages may not be the same. Getting a base-line comparison from the get-go is on-topic. A gas motor burns substantially more fuel than a diesel to begin with, which will obviously have an effect on how you would implement the electric system. My off-topic comment was a joke anyway, but there's a dreadfully thin margin of that around here anyway.
Diesel in general is a very good application for trucks and buses that operate most of the days and nights. For passenger vehicles, gas-electric hybrids are a better solution.
Diesel is a good application for trucks because it's superior performance and economy are obvious to most anyone. The same can apply to passenger vehicles if the correct engines are used. I think the new Mercedes diesel is proof of that. No reason it can't be improved upon with a hybrid system. We shall see how the higher horsepower hybrids with better performance do on the economy side in the real world. The Mercedes is a heavy mid-size luxury car with quite good performance, rated for 27mpg city and 37mpg highway. That's 7mpg better on both ends than a V6 Accord which is substantially lighter. And slower.
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'11 GMC Sierra 1500; '08 Charger R/T Daytona; '67 Coronet R/T; '13 Fiat 500c; '20 S90 T6; '22 MB Sprinter 2500 4x4 diesel; '97 Suzuki R Wagon; '96 Opel Astra; '08 Maser QP; '11 Mini Cooper S
I'd also like some diesel facts... like real-world spreadsheets (ongoing collections of actual MPG data). Having other facts, like maintenance costs and compression loss after 200,000 miles would be beneficial too... since without stuff of that nature helps support the "reliability" claims.
JOHN
'11 GMC Sierra 1500; '08 Charger R/T Daytona; '67 Coronet R/T; '13 Fiat 500c; '20 S90 T6; '22 MB Sprinter 2500 4x4 diesel; '97 Suzuki R Wagon; '96 Opel Astra; '08 Maser QP; '11 Mini Cooper S
It's also quite common on these trucks to have a lot of electrical draw going on. It's normal for trailers to run most of their electrical lighting and such off the trucks batteries.
http://www.prweb.com/releases/2002/10/prweb47344.htm
or
http://tinyurl.com/4l96s
Diesel engines being "heat engines", the thermotunnel diode and diesel engine seem a perfect match. Then couple these two with a hybrid drive train and nanogate capacitors and and and.....you get the picture. The future for transportation is looking great, not gloomy like the eco-whackos would have you believe.
Bryan
Bryan
Gary
http://www.autoindustry.co.uk/news/industry_news/news-5645ciadi6
You bring up some interesting ideas that have been discussed a time or two. I am not sure the American public is ready for 100+ mpg cars yet. They would be a bit short on performance. I would love to drive the Accord diesel as it seems like a great performing high mileage car.