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Diesel Hybrids in our future?

I am wondering if anyone has heard why there is no diesel hybrid? It seems a natural to me (now that diesels have been cleaned up).

They get better mileage and now start quickly, etc. A diesel seems an ideal solution for the Volt, where the engine's purpose is to charge the electric batteries.

Also, home-brew diesel is easier and safer than home-brew gas.

Love the show...



  • edited April 2009
    One would certainly think.

    corperate logic = oxymoron

    Any small engine to turn the generator that recharges the drive battery would do, theoretically. Why don't they ? Will they ? Diesel, biodiesel, alcohol, Mr.Fusion.

    When I bought my Escape hybrid I was aghast and confounded that it is not even offered in Ford's own flex-fuel configuration.
  • edited April 2009
    Simple - cost. If a hybrid costs about $3,000 extra, and a diesel costs about $1,500 extra, then a diesel hybrid could cost $4,500 extra. Say you take a Prius at 50 mpg and add diesel to get 75 mpg. Over 100,000 miles you use 2000 gallons with the gasser, 1333 gallons with a turbo diesel, a savings of 667 gallons, $1,333 dollars at $2/gallon. No payback after 100k miles.
  • edited April 2009
    I have heard of a few planed, but I don't know if they will reach North America.
  • edited April 2009
    I want a high mileage car that follows KISS. Is this too much to ask for? When only 1 man in 10 at the Dealership can use a multimeter (OK maybe I am exagerating but take a look at where American students place in math and science) aren't we on the verge of overloading these people?
  • edited April 2009
    Think about the amount of computers and turbos and injectors and batteries and motors and....
  • edited April 2009
    I don't think that hybrid technology will help a diesel as much as it does a gasoline engine.
    Gasoline engines have a very high idle fuel consumption compared to a comparable diesel, as much as 3 or 4 times as much so shutting off a diesel doesn't save near as much as shutting of a gas engine does.
    There's still the advantage of energy recovering braking but that can be rendered moot if you get out of the habit of accelerating towards each and every red light.
  • edited April 2009
    I don't think that hybrid technology will help a diesel as much as it does a gasoline engine.
    That's a very good argument. I read an article a couple months ago about the Hybrid pickups and how many people didn't think they made much sense because they are only increasing gas mileage by 2-3mpg....However when you look at the % increase in these's MUCH higher then the increase in say the Civic hybrid. A 3mpg increase on a pickup that only gets 15mpg is a 20% increase in gas mileage...THAT'S HUGE.
  • edited April 2009
    A motor in a hybrid currently available assists in moving the car and charging the battery pack. Next generation cars like the Volt use the gas/diesel motor only to charge the batteries, the electric motor(s) move the car. In this case the gas or diesel motor runs at a set speed, and it is either on or off. Idling is not an issue, speed and smoothness of restarting and stopping the motor become important factors. People in the car don't want to hear, feel, or notice when the gas/diesel motor starts and stops. This should be possible in either gas or diesel, but if a gas engine is stopped at just the right point it fires up again very quickly. At this point advantage gas.

    Perhaps we may see the wankel type rotary engine again someday. They are very smooth, low weight, and great power to weight ratio. There are technical issues to perfect with them but they could be worked out. A smaller gas engine allows more room in the engine bay for electric motors and battery packs so the passenger and trunk space can be maximized.
  • edited April 2009
    Agree; these very high mileage vehicles only make sense at very high gas prices and for high mileage drivers. Where I live the cab drivers are now switching wholesale to Prius vehicles. They put on 100,000 miles a year or so, with a lot of stop and go city driving. A diesel hybrid option would pay for itself after a little over a year for them. The current taxis are mostly Crown Victorias, getting an average of 20 mpg on regular gas. Using 5000 gallons per year @ $2= $10,000 in fuel compared to $4000 for a Prius is a complete no-brainer of course.

    Personally, my driving (in my own vehicle ) is down to 7000 miles per year. Last year I spent $859 on gas, so a gas Prius will save me about 60-70 gallons per year or $120-$140 over my 4 cylinder Toyota. The payback for me for a Prius ($9000 premium) is 64 years at $2/gallon and only 32 years at $4/gallon.

    Diesel hybrids are being developed by all European car makers, since diesel is priced much lower and gas prices were $8/gallon last year. We need to go back to $4 gas in North Amercia for diesel hybrids to make any sense.
  • edited April 2009
    Developing a diesel hybrid would be an inefficient use of resources.

    In terms of fuel savings, let's say making the Prius into a diesel hybrid lets you increase from 45 MPG to 70 MPG. That will save you roughly 79 gallons per 10,000 miles. However, increasing fuel economy from 12 MPG to 15 MPG in a larger vehicle will save you about 167 gallons per 10,000 miles. So the focus should not be on increasing fuel economy in vehicles that are already relatively efficient. Much more fuel will be saved by making large vehicles run more efficiently.
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