Slashdot Mirror


MIT study: Diesel Beats Hydrogen For Green Car Power

An anonymous reader writes "Bummer story on Science Blog for people looking to gas up on the H. Even with aggressive research, the hydrogen fuel-cell vehicle will not be better than the diesel hybrid -- a vehicle powered by a conventional engine supplemented by an electric motor -- in terms of total energy use and greenhouse gas emissions by 2020, says a new MIT study. If we need to curb greenhouse gases within the next 20 years, improving mainstream gasoline and diesel engines and transmissions and expanding the use of hybrids is the way to go."

11 of 108 comments (clear)

  1. Not a problem. by Henry+V+.009 · · Score: 4, Insightful

    Don't worry, by 2020 the main problems with C02 emission will be from third world countries with exploding populations anyway.

    1. Re:Not a problem. by lcs-150 · · Score: 2, Insightful

      There are in fact fuel cells that work both ways, creating current from combining hydrogen and oxygen and also flowing backwards to electrolyze water back into hydrogen and oxygen. Some of the energy required for the electrolysis could come from regenerative braking, or turning the motor backwards when going downhill.
      Further, as stated the power has to come from somewhere, and there are always the renewable options of solar power, wind, hydroelectric and others. The article says that the study makes the assumption that hydrogen would come from hydrocarbons, which is one of the things that can be totally avoided with forethought. Why not just plug your car in when you get home at night, and have a full tank in the morning? Even electrolysis off of grid power is more efficient (though still a source of pollution) than many inefficient combustion engines.

  2. Let the political ranting begin by linuxwrangler · · Score: 4, Insightful

    Here in California we are old hands at eco-political ranting that disregards science. So what if diesel can make great strides in reducing polution - is it zero emmissions? No? We can't support it.

    At least California recently backed off it's requirement for a certain percent of all new vehicles to be zero-emmissions (where zero means we moved the emmissions out of our neighborhood and over to the poor area where the power plants are located). The argument was that a better reduction would be had for lower cost by pushing for hybrids. Reaction was swift with the eco-types crying foul even though the switch to hybrid will yield far better results (ie. we can do it on a far larger scale sooner and using our existing infrastructure and it will yield great results).

    A similar "get the cars off highways" by expanding the ferry fleet on the San Francisco bay movement has sprung up and they are trying every trick in the book to prevent acknowledging the fact that the ferrys burn more and pollute more than if every person they carry drove in a single car instead.

    So kudos to MIT for following the science instead of the politics - I just hope they are wearing their asbestos underpants.

    --

    ~~~~~~~
    "You are not remembered for doing what is expected of you." - Atul Chitnis
    1. Re:Let the political ranting begin by crath · · Score: 2, Insightful

      ...So kudos to MIT for following the science instead of the politics...

      Actually, from what the short article says(which is probably incomplete) MIT chose the most "expensive" (from an environmental impact) way to create hydrogen and compared that to hybrid diesel. How would these two technologies compare if fossil fuels were not used to create hydrogen, but wind or solar energy was used instead?

    2. Re:Let the political ranting begin by pmz · · Score: 2, Insightful

      So what if diesel can make great strides in reducing polution - is it zero emmissions?

      At 50 or so MPG for the VW Golf TDI, the pollution must be pretty darn low. And, this car isn't even a hybrid. If hybrids are supposed to be even better than this, I'd say they are a good compromise for the eco-freaks out there.

      A similar "get the cars off highways" by expanding the ferry fleet on the San Francisco bay movement has sprung up and they are trying every trick in the book to prevent acknowledging the fact that the ferrys burn more and pollute more than if every person they carry drove in a single car instead.

      That's because ferries have big-ass off-road-rated diesel engines, while cars have tiny regulated-out-the-wazoo diesel engines. Also, more of the ferry polution goes straight into the water. Motorized boats are pretty nasty when you think about it.

  3. Hydrogen was overrated anyway by chriso11 · · Score: 4, Insightful

    Politically, for Bush, there were two cool things about pushing for Hydrogen cars:

    1) It has a neat hi-tech feel that even the greenest couldn't complain about;

    2) It means he didn't have to do anything about SUVs or CAFE or such, 'cause, after all, he supports Hydrogen.

    Why is it any surprise that Hydrogen is not a real viable solution?

    --
    No, I don't trust in god. He'll have to pay up front, like everybody else.
  4. Re:Where do we get the H? by Xunker · · Score: 4, Insightful

    Windmills, of course.

    Tidal power, too.

    Solar?

    Some may argue the real draw of Hyrogen is not the clean-ness of the power as much as it is the ability to store it.

    Electricity is hard to store; Batteries must be huge to store large charges, and even then the larger th battery the faster it loses it's power in parasitic loss. Hydrogren, OTOH, is easy to store; presurize it, freeze it, whever. It's not as easy as a fluid such as oil, but loads easier than electrons.

    So you get windmills. No, not some nebulous organization, but YOU, the consumer. You have one or two that run all the time. They generate tiny amounts of power, and this power cracks water though hydrolosis to get your hydrogen and have it in a storage tank out back of your house (like propane). When you need it, you pull it out of the tank.

    Long story short: you get the same amount of energy back from a power cell as the engery it took to get the hydrogren in the first place (minus pesky thermodynaics): the good part is that using H you don't have to generate it all at one time -- you can do it over time using power from low-yield-long-investment instalation like wind, solar. geothermal, etc.

    (I still understand what you're saying, though -- until efficient molecule-crackers are common, we'll probably end up using hydrocarbon fuel to power machines to produce our hyrdo, or decompose hyrocarbons directly.. but we don't have many options at the moment)

    --
    Hilary Rosen's speech was about her love of money and her desire to roll around naked in a pile of money.
  5. Where is the nuclear option? by jakedata · · Score: 3, Insightful

    Nobody ever mentions nuclear power in relation to hydrogen manufacture. It is undoubtedly in the back of some people's minds but they dare not mention it for fear of alienating many of the very people that support hydrogen.

    Now I am not advocating the proliferation of today's (really yesterday's) messy fission plants but let's support research into modern nuclear technologies be they fusion or fission.

    Nuclear CAN be clean. Give it a chance.

  6. Pouring money into hydrogen infrastructure. by Odinson · · Score: 2, Insightful
    The only problem isn't with research, but the appearance of research. Big government needs to dump big money into research for fueal cells for any company to seriously consider building nationwide chains of natural gas to hydrogen converter stations.

    Diesel and Gas, however just require slight modification to exisiting use and application. They require little new infrastructure. They are going to happen naturally in the market now anyway.

    Hybrid cars will be the temporary stop. Eventually leading to fuel cell models. Hybrids don't need any more boost than the current state of oil prices.

    Look at Tommy's new hot rod, he got the big wet one!

  7. Diesel or Biodiesel? by KillerBob · · Score: 3, Insightful

    There's a difference. Biodiesel is available today, and will run in all Diesel engines. It's clean and cheap: 1L of vegetable oil will make 900mL of Biodiesel. It's becoming even cheaper to manufacture as it comes into use, and with the rising price of oil, Biodiesel is approaching par with gasoline.

    Take a look at the emissions here. Significantly cleaner than Diesel, which is cleaner than Gasoline anyway.

    Biodiesel is definitely a much more viable and clean alternative to hydrogen fuel cells. It isn't quite as clean as H2 cells, but it's available now.

    --
    If you believe everything you read, you'd better not read. - Japanese proverb
  8. My hunchback was correct! by Graymalkin · · Score: 2, Insightful

    If you can maintain an air of hype-proofness it is fairly easy to see how stupid the "Hydrogen Economy" ideas are in both the short term and long term. Hydrogen is merely an energy carrier a finicky one at that. Many of its proponents only see the end result, a car that spits out warm wet air, without fully realizing the infrastructure that warm wet air is generated with.

    Diesel, especially biodiesel has a much better cost/benefit analysis but isn't as sexy as technology as hydrogen. Even the word Diesel fares ill in comparison to the dynamicism of hydrogen's syllibles. It also seems to me that the American public, three quarters of which live in urban areas, connotate Diesel with dirty and noisy MAC trucks and pubtrans buses. If they're a little more technical they probably instantly think of Diesel cars like the TDI Golf and Jetta with their 90hp-I-think-I-can-make-it-up-to-passing-speed engines.

    What Diesel hybrid proponents ought to do is start up a massive test drive program. Give a couple people the keys to a Diesel hybrid for a week with a full tank. If more people see they can actually use freeway on-ramps effectively AND have most of the tank of gas left by the end of the week they'd see Diesel hybrids and hopefully Diesel engines in a much different light. Electric assist makes a huge difference in the car's feel, especially for those who shun anything that won't pop off a light like a Roman candle.

    The Honda Dualnote concept car is an excellent example of this idea, the combustion engine charges an ultracapacitor while idling or braking. Said capacitor gives an extra umph (100hp worth) when accelerating. If you were to stick such a system on a high efficiency yet power deprived car like the TDI Lupo it'd make for a fair bit of go juice without expending a ton of gas juice. Citroën and Audi have shown that it is possible to make exceptionally clean burning Diesels which is promising for the Diesel-smells-like-poo opponents. Nissan's Gloria is making some great advancements using toroidal CVTs instead of conventional gearboxs.

    These sorts of advances lend well to designing a really badass Diesel hybrid. From conception to fruition Diesels are going to be far cheaper than any hydrogen powered car for the next several decades. Diesel fuel is much easier to store and transport than pure hydrogen, it is more robust than methanol, and with biodiesel is renewable and is only pumping the CO2 back into the environment that was used to grow it.

    Hype about hydrogen based utopian societies are the same sort of pie in the sky crap that has been fed to people about fusion power. It's payoff point is always somewhere out in the distant future where we all use transporters to get to work. Hydrogen COULD be viable as could nuclear fusion. They could be viable technologies at a point in the future but not now and not any time soon. Hyping these technologies up does little to fix any problems anyone has in the here and now which is where we live.

    Hydrogen will be a good idea some day but unfortunately not today. Until then we ought to work towards improving what we have available to its most efficient state while working on the technology of next year. I personally think Diesel's time is due but clean and efficient gasoline engines would work just as well for me. I just want more cars on the road with that get 40+ miles per gallon. I'd really love to see 90+ miles to the gallon. The more fuel efficient our cars get the less dependent we are on the gas pump to lead functional lives. Three times the gas milage means a third of your current fuel expenses. I'm sure everyone in meat space can find a use for a couple hundred extra dollars left at the end of the year, for some a few thousand.

    --
    I'm a loner Dottie, a Rebel.