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  1. #201
    Guest

    Diesel vs. Hybrid: A Point Missed

    Another missed point is looking at the midsize to large "family car". The Hybrid Escape is the closest vehical and gets an average 31 mpg and if you have more then two kids it just doesen't have enough space. Your average minivan gets about 22 mpg on a good day. The hybrid vehical, and I'm guessing at this, will have a significatly lower mpg if it is towing or filled with adult size passengers and it's advantage will decrease futher if the vehical is larger. Deisel's are known for their torgue and power and will be needed for large family and comercial vehicals. Both technoligies HAVE to be further developed because both have a lot of advantages that we need to meet our various driving needs.

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  3. #202
    Guest

    Diesel vs. Hybrid: A Point Missed

    I had to check the dates of these posts because you guys are talking about biodiesel as a FUTURE technology. Huh? I have an unmodified Mercedes 300 Turbo Diesel that I run unmodified on biodiesel right now. I live in the Denver area and there are several places to get B100 (100% biodiesel) in Denver, several in Boulder and a few more scattered around the state. And it's growing, fast.

    So in all this discussion, the hybrid people keep acting like biodiesel is somehow non-existant, or at the same stage as fuel cells. This is just totally innaccurate. My emissions are significantly reduced (no black smoke with B100). My exhaust smells like vegetable oil (no offensive diesel smell.) Biodiesel is real, it's fueling my car as we speak. Wake up folks. I know that if you just bought a hybrid, psychologically it will be near impossible for you to admit that biodiesel is the most environmentally responsible decision, but my car uses no petroleum at all. (I use synthetic motor oil, not that it matters with such tiny amounts.) You guys are really scratching at anything that will justify the fact that you bought a so-called environmentally friendly car that still runs on conventional petroleum (the very resource we are running out of.) So, biodiesel is cleaner than gasoline, and it's not made from petroleum. Plus it helps farmers in the United States rather than the Saudi and Bush royal families.

    When making your arguments, you continue to ignore the fact that many diesels (all the school buses in Denver and all the public busses in Boulder) run on a fuel that uses no petroleum. None. None beats less anyday.

  4. #203
    Guest

    Diesel vs. Hybrid: A Point Missed

    Jim,
    The myth that an electric motor is low torque and power is just that: A myth propagated by golf carts and cheap hobbyists who are stuck with no source of cheap, powerful electric motors or batteries. You'll note that the most powerful vehicles in the world: railroad locomotive, huge mine earth movers, and ships already use the hybrid diesel+electric propulsion although very few use batteries to store the electricity since they are subject to pretty much constant loads. There is absolutely no reason for electric and hybrid electric vehicles to be restricted to small vehicles.

    The electric drivetrain is more efficient than a pure ICE + transmission any way you slice it.

    The only real limitations of the electric drivetrain have been:

    1. expensive - because they haven't been mass produced or hybrids which are such a hot commodity that I can't blame Toyota and Honda from milking their cash cow while they can.
    2. short range - back when lead acid batteries were the only economical choice. NiMH and Li-ion have made the 200 - 300 mile vehicle quite feasible if only someone would mass produce large form factor batteries
    3. slow charging times - Modern chargers can 80% charge batteries in 10 - 20 minutes with industrial grade power supply (overnight charging is required with residential power levels)

    But the real limitation to electric vehicles is that they threaten the status quo and the knowledge base of the gear-heads who control the automotive industry.

    Suddenly, the geek with a soldering iron in his clean hands controls more power than the grease monkey who has been skinning his filthy knuckles all his life. All the old guys (read these diesel posts for examples) who have spent time tweaking carbuerators, timing belts, injectors, etc hate the thought of anything new coming along. Just as the old sailing masters fought the onset of the steamship in the 1800s, today's mechanical masters fight the electron's natural replacement of the ignition as a way to move mankind (enabled by the wizards of modern chemistry).

    Even putting a wimpy electric motor into the drive train of a normal Honda Civic can improve the fuel economy by about 30%. Imagine what even more electric drive will do.

    Or don't even bother to imagine. On July 19th, Tesla motors will be unveiling their new pure electric sports car. They've chosen to tackle the top of the ICE world with a car that will easily defeat the best ICE cars including the Ferrari, Porche, Lamborghini, Viper, 'Vette, etc. It will travel over 200 miles on a charge, accelerate from zero to 60 in less than 4 seconds, . . . Yet it gets effectively over 100 (well-to-wheels) miles per gallon (maybe not while accelerating at that rate :-) and it will be cheaper than the Ferrari as well.

    end of rant. More on the Tesla later.

  5. #204
    Guest

    Diesel vs. Hybrid: A Point Missed

    I find some of the comments rather offensive as if there is no way that several technologies could compete. It is true that Diesel technology, or internal combustion engines (ICEs) in general have a 120 years old history, but that is exactly their advantage, we know how reliable they are, we know their strengths and their weaknesses, and we also know that their technical development potential is far from being achieved. Electric motors incidentally are just about as old, but here we are still struggling with the same problem of 100 years ago, how to efficiently store electric energy. I am sure you know that firt speed record holders in the late 1800s early 1900s were electric driven. Today we have a variety of technologies, we have hybrid, which convert fossil fuel to internal combustion, to electricity, to motor power), we have ICEs which connected to transmissions do the same thing, convert fossil fuel to internal combustion into mobile power.

    Arguably the efficiency of the conversion mode to motor power of both technologies is about the same. A multi valve turbo-diesel engine with a 5-6 or more speeds gets in mixed traffic comparable fuel consumption to a hybrid. At very high speed with very high loads, the diesel might even have a slight advantage since power demand increases exponentially with speed. The big advantage of the hybrid is that it can use the energy from braking that is lost in a conventional vehicle to store up motor energy. That makes the hybrid an ideal transport in town, with stop and go, which constitutes much of our traffic pattern. Without this ability to regenerate energy, the actual efficiency of the hybrid vs a conventional vehicle with a direct transmission (manual or "powershift") is about similar. The net efficiency of a gearbox where all forces flow in a linear fashion to transmit energy is around 95%. The big draw back is the engine that in a gasoline version does at best maybe 30% fuel conversion to motor power, and in case of a modern diesel maybe, 35 to 40%. The hybrid is really facing the same reality, it has an ICE that runs at around 30% efficiency which power is converted to electric power/motors that have around 90% to 95% efficiency, however, it has to drag along a certain amount of battery storage.

    Expensive materials and designs then have to be used to try to reduce vehicle weight back to a competitive level. I find it astonishing that the Prius or Honda do weigh relatively the same than vehicles of similar size and equipment. To me it suggests that quite a bit of the extra money that is paid for these two particular hybrids also goes into lightweight body design.

    The hybrid is without a doubt a great development, but it is a compromise and consequently not an optimal solution. At the same time, the hybrid’s ability to reuse some of the power lost at braking is something that has huge potential. But there could be many methods to do that, mechanical/hydraulic accumulators, electric regeneration as hybrids do, but also compressed air, maybe even a spring as in toy cars, etc.. Without a doubt the hybrid has changed the automotive landscape. Healthy competition among varying systems (that includes driver/user preferences) is most likely to provide a viable solution.

    Still, however, it is not a reason to call disbelievers “grease monkeys” as electric cars too, at least in the close future still have tires, drive shafts, and tie rods that need periodical replacement, and foreseeably that won’t be done with a soldering iron.

  6. #205
    Guest

    Diesel vs. Hybrid: A Point Missed

    Hi Diesel driver:
    I'm also purplexed how some embrace a single "my car is better" attitude and completely shut out other technologies.

    To ExEV1's credit he spans both EV and gasoline-electric.
    I'll have to agree with most of his statements regarding the EV. Even though I drive 100 miles/day I'd love to have, and would buy and EV with 300 mile range, sold at compeditive prices and with good warranty. So much more for someone with shorter commute. I do believe technology is already there except possibly battery cost.

    Hybrids, gasoline, diesel and bio are all compromise, a stop-gap. How much better to plug into a grid and let clean nuclear do its work.
    I think a point ExEV1 was making is that EV's don't have engine oil to change and practically all drivetrain maintenance is eliminated. No coil packs to go bad, no injectors to clog and no cog belts to stretch.
    A battery, electric motor, a transmission and a controller. Surely any vehicle requires regular maintenance but the EV is vastly simpler. Less to break.
    ExEV1 also makes an excellent point about lobbyists for the automotive industry. Consider the Fair tax http://www.fairtax.org this would eliminate 99% lobbyists, 60,000 pages of tax code, payroll taxes and end the IRS.
    Politicians are going to have to be forced to adopt this because it transfers 90% of their power back to the people.
    Similarly automotive mechanics would loose much of its bussiness replacing plugs, CAT converters, turbos, scrubbers etc. Automotive lobby is one of the most powerful. There you have it.

    You made the point that ICE's have been developed for 120 years and have been advancing, but then say battery technology has not.
    That is flat false. (Most people already know this)
    Diesel, gasoline, EV, hybrid all have their inherant drawbacks which can be traced to its inception.

    You're right to say that diesel and hybrid get about the same efficiency and mention regen braking. You may not know this, but for many of us regen isn't used very much but still get a big benefit.
    90% of my commute is freeway and like saving pennies for eventually dollars, ICE recharges the battery-The load is usually very light that ICE doesn't even notice. But you still have a full battery by the time its needed.

    You mentioned suprise that the hybrid weighs about the same as comparabe vehicles.
    Prius and Insight bodies are especially made for efficiency but all other hybrids are not. Civic Hybrid is a real-true Civic, etc. Nothing is changed to reduce weight. Hybrid components are not extraordinarily heavy. It's a myth.

    Steve-
    I don't think anyone here is saying biodiesel is at the same stage as hydrogen cells but does lack both distribution and vehicles to burn it.
    A couple months ago a bio enthusiast sent me a link of nationwide stations which distribute it.
    The closest station is about 35 miles away, not close at all.
    In my own case wouldn't buy diesel for the MPG limitation.
    I admit being totally radical about efficiency and certainly don't drive "normal" but I'm getting +900 miles and up to 73MPG in my hybrid Civic. Bio can't touch that in a comparable vehicle.

  7. #206
    Guest

    Diesel vs. Hybrid: A Point Missed

    DD,
    Sorry if you were offended. I tried to offend both the geeks and grease monkeys equally so you'd see I really have respect for both stereotypes.
    I must admit, I really appreciate your comments so please don't take additional offense when I try to address them.

    Electric motors: While nearly as old as the ICE, modern semiconductors have increased their efficiency and reliability, something that increases their viability today.

    Energy Storage: We've seen at least a 400% increase in energy storage capacity over the past 2 decades as well as a reduction of toxic materials and increase in charging speeds and charging efficiency. These were clearly limitations in the past, however, the battery research of the past 2 decades driven by EV money and the laptop/cellphone industry has been quite successful.

    ICE efficiency: today's hybrids have been held back by the ICE industry (at least they weren't killed as the pure EV was) so they haven't exploited the fact that an electric-primary or strong (such as but not limited to serial hybrids) enable the ICE to be optimized for constant speed, constant load operation. This should enable a good diesel to approach 50% efficiency.

    Dragging around battery storage and regen braking: You are right that a limitation of any battery powered vehicle is the weight of the battery. This is similiar to the Energy Storage problem above but it is true. Pound per pound gasoline + ICE is a lot (I don't have the numbers with me now) lighter than the best battery + electric motor. Fortunately, the regenerative braking offsets the weight as the biggest weight penalty is in startup and climbing which are offset somewhat by braking and descending with a hybrid.

    The hybrid benefits you've missed: the missing benefit of a hybrid is that the power of the ICE can be reduced to slightly more than the average horsepower needed to propel the vehicle while the electric portion can easily handle the surges.

    A plug for plug-ins: The benefits of plug-in vehicles, even beyond gas-only hybrids is that the total efficiency of the battery electric drive train + electrical grid + stationary power station is much better than any form of pure ICE if you measure the well-to-wheels losses. Additionally, the plug-in can run off of any form of energy that can be converted to electricity, nearly anywhere on the content. Therefore, windfarms in Wyoming can help, as can solar in CA, NV, and AZ, while hydro in the northwest, natural gas, sewage gas, etc, can all power any plug-in car. ICE's can only run off of a portable, fluid fuel.

    A comment on maintenance: I have never had to change a drive shaft. Never a tie rod (when I was behaving nicely on a road :-), Sure, tires need changing as might shocks. But hybrids/EV's rarely need new brakes, never need oil changes or transmission fluid. I did have to replace motor mounts several times on my EV1 but that was an infant mortality problem since on their first try, the glorious GM engineers clearly underestimated the torque that an electric motor could produce when 'educating' Porche's. One beauty about things done with a soldering iron is that they have far fewer failure modes than mechanical things with moving parts and are very efficient. Modern power supplies can do voltage and frequency conversion with 90 to 95% efficiency.

    Alternative hybrids:
    You've named several alternatives and missed a few as well. I'm not going to rain on any of them since I'd like to see all given a level playing field. You did, however, miss the flywheel which is probably more likely then the ones you did mention. I'd even like a little of the $1.2 billion that was given to hydrogen fuel cell research spread among them all since they seem as likely as HFC's to solve problems. I also did not appreciate the HFC being used by GM as an excuse to kill the EV1 and the battery EV. Unfortunately, the driver today has only one real choice of energy with which to drive - petroleum+ICE directly coupled to the wheels.

    Sorry if you were offended by the "Grease Monkey" label. Maybe I'm a bit sensitive to GM killing the best car I ever drove so I don't realize how harsh I sound towards those who cannot change their views and, instead, kill anything new that comes around.

  8. #207
    Guest

    Diesel vs. Hybrid: A Point Missed

    Hot_Georgia wrote:

    "Why do I say anti-hybrid?
    1. Zero mention of hybrid positives.
    2. Practially all owners love them.
    3. Huge difference in MPG potential vs most every other vehicle on the road.
    No mention of the +100MPG Insight, the +70MPG Civic or +100MPG Prius
    4. Many if not most actual, real hybrid owners are saving money. "

    Look at those mpg numbers above!!!
    Is Hot_Georgia going beyond "wishful thinking"
    Insight EPA is 57/56 Civic Hybrid 49/51
    Believe Prius is 40-50 and a Prius owner on
    this blog reports 46.5 mpg average over 45000miles.
    Realize driving styles can be different among drivers,
    but does Hot_Georgia really believe we believe
    his mpg numbers. Maybe true if it is recorded going
    down from Pikes Peak, CO!

  9. #208
    Guest

    Diesel vs. Hybrid: A Point Missed

    EV-Driver, thanks for the thoughtful reply. It is not so much that I took offense myself. I work in development, in poor countries on issues which generate even much further differing opinions than the ones I find on this site. I follow these dicussions and sometimes jump in just because of my initial background in engineering, and my personal interest in the topic (sadly and ironically, many developing countries are hugely innefficient in energy use). Today my work is much closer to economic and financial management and completely unrelated.

    I really am not up to date about the latest technological advantages in regards of power storage/battery/accumulator designs. I do appreciate your insight and dedication to the comments on this site, I think this is very healthy and this forum might indeed be quite a good source of ideas, even if some are rather out there.


  10. #209
    Guest

    Diesel vs. Hybrid: A Point Missed


  11. #210
    Guest

    Diesel vs. Hybrid: A Point Missed

    Dear Hot Gerogia - thanks for your comment. I would like to correct you on the point I made concerning electricity storage. I did not say that there has been no progress in battery storage, I just said that the struggle to store electricity efficiently remains one of the main challenges of electric vehicles. I cannot say with any sense of accuracy how much progress has been made in that field, but storage does in fact remain a problem.

    I am also willing to challenge your point about "clean nuclear" technology, and you are probably aware that I would not be the only one to do so. While production of electricity is indeed relatively clean (although not cheap) with nucelar power plants, you will have to admitt that this mode does generate a rather nasty waste no one really wants to have to close to their back yard. And we have not really yet found a safe way to dispose of it. The methods we use today can at best be called "let us all hope for the best" no one really wants to hear about the worst possible option. And I am not even thinking of theft and terrorism, and the process of extraction of uranium, and the political economy of some of the countries where this stuff comes from. Conversion of the waste as fuel in plutonium reactors as the French (and Japanese) have been doing it with limited success (and fairly high failure rates) is also only moderately promising. Real progress will only be expected with fusion technology, which is something considered at least 4 decades away. So, sustainably generating clean, and cheap electricity does remain a challenge with the grid as well. Maybe that is where the problem is, generation might be better (more reliable, and cheaper, although not necessarily more effiecient), if it were more decentralized, many small plants throughout the country, with wind, sun, thermal power (ground water), gas, etc.. The problem is that many large energy companies would radically oppose that since they would not be able to control the taps anymore. Anyway, it is a never ending subject.

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