Slashdot is powered by your submissions, so send in your scoop


Forgot your password?

4 Tons Of Plants per Mile to Ride In Your Car 995

Roland Piquepaille writes "As you might know, I enjoy big numbers. So it's just natural that I was attracted by this news release from the University of Utah, "Bad Mileage: 98 tons of plants per gallon." "A staggering 98 tons of prehistoric, buried plant material is required to produce each gallon of gasoline we burn in our cars, SUVs, trucks and other vehicles." For a reasonably efficient car, riding 25 miles per gallon, this translates to 4 tons of prehistoric plants per mile, or more than two tons per kilometer. The research paper also mentions that everyday, we are using the fossil fuel equivalent of all the plants growing during a whole year just for our cars. Even if these numbers are too large, this still makes you think about how inefficient our cars are. This analysis describes the calculations and contains other details about the research paper which will be published in November by Climate Change."
This discussion has been archived. No new comments can be posted.

4 Tons Of Plants per Mile to Ride In Your Car

Comments Filter:
  • by QEDog ( 610238 ) on Monday October 27, 2003 @11:16AM (#7318795)
    Reminds me of an article posted in /. before that said:

    "Building more roads to combat traffic congestion is like buying a bigger belt to combat obesity"

    • by Bytesmiths ( 718827 ) on Monday October 27, 2003 @01:12PM (#7319801) Homepage
      I cut out the middle man. To me, it isn't the amount of plant matter consumed by cars as it is the millions of years it takes to convert it to petroleum products. All that carbon has been sequestered for millennia, and we're just shooting it into the atmosphere.

      So I do away with the process of turning plants into petroleum, and burn the plants directly in my engine. Anyone can do it! You only need:

      • a diesel powered vehicle, and
      • a way to thin vegetable oil, either
        • alcohol and a base catylist (typically methanol and lye), or
        • a heater to bring vegetable oil up to about 80C (180F).

      With either method, waste vegetable oil from restaurants can be used, solving two problems at once!

      With the exception of nitrous oxide and CO2, vegetable oil powered diesels are MUCH cleaner than petro diesels. Yes, they produce climate-warming CO2 in similar quantities to petro-diesel engines, but the CO2 they release was taken out of the atmosphere last year, NOT millions of years ago.

      It is unlikely that Big Oil is going to embrace this, but you don't have to go it alone. Co-ops for producing and/or distributing biodiesel are sprining up like rapeseed oil plants. Google for "biodiesel," "SVO," "WVO" for more info, or visit for more information.

    • Many environmentalists and not a few posters to this thread noted the hidden costs of cars -- pollution, asphalt wastelands, and urban sprawl are real problems not bundled into the price of cars and gasoline. But nobody talked about the hidden benefits of cars to society. High-speed time-efficient personal transportation both reduces the personal cost of consumer goods and provides a better workforce to companies.

      Driving gives employers access to a much larger pool of potential applicants and people a
  • burgers (Score:5, Interesting)

    by matticus ( 93537 ) on Monday October 27, 2003 @11:16AM (#7318796) Homepage
    and every time I eat a burger, 2 tons of modern plants died to make that cow (or something like that).
    We all know the cars burn too much energy. how long of a period were plants compressed for oil? thus, how long until we run out?
    • Re:burgers (Score:3, Informative)

      by Anonymous Coward
      I think the artical is misleading. Not all of the plant is converted to oil only a small part. This is intuitive, becouse your car dosen't carry 52 tons of gas in its tank. Also, gas is one of the best ways to back that much energy in to a small space.
      • Re:burgers (Score:5, Insightful)

        by greenhide ( 597777 ) <{moc.ylkeewellivc} {ta} {todhsalsnadroj}> on Monday October 27, 2003 @12:15PM (#7319331)
        Also, gas is one of the best ways to back that much energy in to a small space.

        Yeah, but a Hummer is not the best ways to use that energy, which is the real point of the article.
    • Re:burgers (Score:5, Insightful)

      by misterpies ( 632880 ) on Monday October 27, 2003 @12:05PM (#7319253)
      Major logical fallacy: that 2 tons (or however much) went to make the whole cow, not a single burger. Your single quarter-pounder is no doubt equivalent to several pounds of cowfeed, but that's nothing like as ineffecient as the conversions being talked about here.

      Moreover however much the cow ate, its food came from recently grown, mostly sustainable sources (eg hay). It's carbon neutral over a matter of years. Burning up fossil fuels at this rate would be carbon neutral only over thousands if not millions of years, i.e. it would take that may years of plant growth to put that carbon back in the soil.
      • Re:burgers (Score:5, Interesting)

        by CKW ( 409971 ) on Monday October 27, 2003 @01:46PM (#7320098) Journal

        Cows themselves are 1000 pounds or so.

        A quick search shows that a cow will eat 25 pounds of hay per day [] - and the average age when taken to slaughter is 4-5 years [].

        That means one cow requires 41,000 pounds of feed over it's life, that's 20 tons. The amount of usable meat is around 700 pounds [] (although only 100 pounds or so is used for hamburger meat, but that's just the typing of the meat).

        So for every single pound of (hamburger) meat, you need 58 pounds of hay. (Fair deal if you ask me.)

        We haven't added in the transportation and processing costs, which if we used current plant matter instead of 10,000,000 year old refined plant matter, would increase it by how much? (Sorry, I'm not going to do that calculation).
        • Re:burgers (Score:4, Funny)

          by Rogerborg ( 306625 ) on Monday October 27, 2003 @02:56PM (#7320741) Homepage
          I note that you cited a PETA claim as one of your sources. If PETA told me that cows eat grass, I'd go and check myself to make sure.

          Beef cattle are slaughtered at 18 months. Add a little more for the breeding cows, and you can push it to two years average. Find your own links.

          Since your 700/100 lbs per cow is from a completely unreferenced anecdote, I'll throw in one of my own. McDonalds burgers are 100% beef, because they are (very nearly) 100% of the cow. Picture a huge cow sized grinder, making cow paste. You don't have to believe me; instead, find me anyone who works in the slaughter industry who'll eat a fast food burger.
    • Re:burgers (Score:3, Insightful)

      by b!arg ( 622192 )
      Just a random thought, which has probably been refuted before and makes no real economic sense, in any sense of the word. It's also probably the complete wrong direction to go too or is being done already and I'm missing something competely(is that enough qualification for you?). But if we can compress carbon to create diamonds, why can't we grow plants and compress them to create oil? I'll go back to my coding now...
    • Re:burgers (Score:5, Funny)

      by nizo ( 81281 ) on Monday October 27, 2003 @01:21PM (#7319872) Homepage Journal
      But you know what keeps me up at night? Our bodies are made up of matter that came from dying stars, how many stars had to die to make each one of us???
  • you assume (Score:2, Insightful)

    by Anonymous Coward
    That plant material is the source of the oil reserves. I do not think there were ever enough plant mass ever to give us the amount of oil we have presently. FP
    • Re:you assume (Score:3, Informative)

      by wa5ter ( 628478 )
      What are you suggesting? There is no shortage of clear proof that this is where the oil comes from. Coal contains clearly fossilised plant material.. oil and coal and natural gas are often all found together. The process of generating them can be simulated very easily.
      • Re:you assume (Score:5, Interesting)

        by mikerich ( 120257 ) on Monday October 27, 2003 @11:41AM (#7319029)
        There is no shortage of clear proof that this is where the oil comes from. Coal contains clearly fossilised plant material.. oil and coal and natural gas are often all found together.

        Actually there is some evidence for a non-biogenic source for some oil reserves. It came as a surprise to me as well when I did my geology degree.

        Thomas Gold (most famous for his Steady-State Theory of the Universe) postulated that oil might be formed from organic compounds deep in the Mantle which migrate up to the surface. IIRC he persuaded the Swedes to sink a test well into ancient hard shield rocks (where there should be no signs of hydrocarbons) and indeed traces of such compounds were recovered. Now I don't know whether they excluded the possibility that they were products of the lubricating mud used to drill the well or if they were younger oil seeping into the basement rocks from a distant reservoir.

        However, the vast majority of oil reserves are clearly from fossilised plants. The breakdown products of porphyrins (the complex organo metal compounds such as chlorophyll) can be extracted from most crudes.

        Finally, oil, coal and natural gas may be found close to one another, but are usually not. For instance, the mainland of the UK has enormous coal reserves, but only one productive oil field and no on-shore gas. British oil probably originates in the Kimmeridge Clay - an organic rich clay that was formed in the late Jurassic. Conversely, the Middle East almost entirely lacks coal, but holds 60% of the World's petroleum reserves. The closest association is usually natural gas and oil - where it has been driven off from oil reservoirs that have been heated.

        In the Southern North Sea much of the natural gas probably came from the underlying Coal Measures which have been deeply buried and exposed to intense heat.

        Best wishes,

        • Re:you assume (Score:5, Informative)

          by Hits_B ( 711969 ) on Monday October 27, 2003 @12:20PM (#7319391) Homepage
          I hate to split hairs here, but as a geologist who has worked in oil and gas exploration I need to clarify a few points. First, if you assume a biogenic origin for hydrocarbon deposits then you realize that different types of organic matter generate different types of hydrocarbons. I need to quote F.K. North from his book Petroleum Geology. In it on page 53 he states " Oil is not derived, as coal is, from terrestrial plant materials." As a result plant material is responsible for the generation of natural gas. Liquid hydrocarbons originate from the sapropelic material that typically is aquatic algae and may include some spores and pollens.
    • Very true (Score:4, Interesting)

      by heironymouscoward ( 683461 ) <> on Monday October 27, 2003 @11:38AM (#7319008) Journal
      There are several theories that hydrocarbons come from something else than compressed rotting plants.

      The evidence is mainly circumstantial, and based on the observation that oil & gas seems to be linked to geographical formations like volcanoes and thin crusts rather than being tied to (e.g.) coal deposits, which would seem more likely.

      Coal, after all, does contain plant remains enough to prove that it's most likely compressed peat and bogs.

      But oil is a bit wierd. My theory (and it's probably not original) is that hydrocarbons are remains of annobacteria colonies that live off sulphur compounds deep in the earth's crust. Such bacteria are known to exist, observed around volcanic vents in the ocean floor, for instance.

      Now imagine _really_ large colonies of such bacteria, living in hot porous sulphur-rich rocks, and dying to rot and produce oil and gas.

      Seems more likely than (oil = compressed dinosaur bones and cabbage) to me.

      Which also implies that oil is a much more massive resource than previously thought, it won't run out soon, but instead the problems it causes (global heating, oil-driven warfare in poor countries) will continue for a long time to come.
  • by Biff98 ( 633281 ) on Monday October 27, 2003 @11:17AM (#7318804)
    Internal combustion engines have ALWAYS been inefficient. There have been attempts to make them more efficient, but there has NEVER been an engine based on gasoline that has exceeded even 35%. Even rotary engines are very poor producers of energy to a set of tires. Just the facts of life.

    Anyone for Hydrogen?
  • by ratbag ( 65209 ) on Monday October 27, 2003 @11:18AM (#7318812)
    25 miles per gallon is many things, but reasonably efficient isn't one of them.

  • by YetAnotherAnonymousC ( 594097 ) on Monday October 27, 2003 @11:18AM (#7318813)
    Isn't most of the original biomass water that does not end up in the oil/coal/gas deposits? Or am I missing something.

    I just don't quite see the point of the guy who did the calculations/report... and I did read the article. This is just throwing around big meaningless numbers. At least Ig Nobel candidate material is train-wreck-interesting.
    • Well here are some percent water composition numbers for various fruits and veggies from a Virginia Farm Bureau article [].

      Let's say plants are 75% water (probably a bit high, but I'm being conservative here). That 4 tons of wet-weight per mile becomes 1 ton of wet-weight per mile. It's all in the same order of magnitude. 2000 pounds of dried spinach to push my car 1 mile is still a lot of plant matter.

      Anyway, I think the point of this calculation is similar to the point being made by those illustrative l
      • It's a selective usage of statistics at best and an irrelevant spin on an irrelevant fact designed to decieve people to win supporters in the most likely case.

        This article is fraudulent.

        Lets start with the easy one. First, they write off as waste all the other products of the oil that don't become gasoline. So, remove another 50% from the tally...

        Next, they add the weight of all the plant that didn't manage to become oil, even after all the water is disregarded. In fact, the multiply their figure by 10,7
        • Sorry, I meant to say if you're not looking for solutions, don't waste money on research...
        • by poot_rootbeer ( 188613 ) on Monday October 27, 2003 @12:06PM (#7319268)

          Could you maybe tell us WHY it's "fraudulent" to include all the parts of the prehistoric plants that don't get turned into gasoline?

          Take that away, and you've taken away the part of the figure that people can relate to. We all know what living plants look like, what with their water mass and their insoluble fiber. If you take only the stuff that becomes gasoline, what does that look like? Is that crude oil? I don't even know. Now THAT would be a meaningless statistic.

          it doesn't matter how many dead, prehistoric plants were required to make the oil we use.

          I disagree. No one would argue that oil is a renewable resource, but studies like these demonstrate just how much of a resource drain it is.
          • by ivan256 ( 17499 ) * on Monday October 27, 2003 @12:16PM (#7319342)
            Take that away, and you've taken away the part of the figure that people can relate to.

            That's why it's fraudulent. They needed to artificially inflate the number to make people relate to it. I can think of a million apt analogies, but let's suffice it to say that I could relate any meaning I wanted in any reasearch I wanted to do if I were allowed to multiply the resluting data by 10,000, or .00001.

            To make maters worse, there are plenty of valid arguments against oil use. There is no reason to fabricate addtional arguments by twisting some meaningless numbers into a suggestive paper.

            but studies like these demonstrate just how much of a resource drain it is.

            No, studies like this plant a totally false impression of how much of a resource drain it is. We could extract the same energy from far fewer plants because we don't have to throw away 99.990% of the plant before we start.
        • by CharlieG ( 34950 ) on Monday October 27, 2003 @01:15PM (#7319829) Homepage
          Actually, what I find interesting is "4 tons" like that is a BIG number

          I live on a small plot of land in NY - 50x100, and most of THAT is house

          From April till Mid October, I take 10 cubic feet of grass clippings/week off my lawn. Call it 28 weeks. That's 280 cubic feet of grass clippings, at 24 lbs/cu ft, or 6720 lbs (Note only about 1/4 of that property is grass) - then figure in leaves from the trees - another 120 cubic feet, at 14lbs/cu ft. Thats 1680 lbs - so I "raise" a total crop of 8400lbs of clippings/leaves per year, or 4.2 tons. Note, this doesn't count growth of the trees. Maple comes in at about 37lbs/cu ft (DRY - green is MORE) Oak is about 45 lbs/cuft. Think how many cubic feet are in an oak tree - you probably have 10 tons or more in a typical full grwn tree
  • by jeffkjo1 ( 663413 ) on Monday October 27, 2003 @11:19AM (#7318818) Homepage
    Even if these numbers are too large, this still makes you think about how inefficient our cars are.

    I think it shows how inefficient mother nature is. Stupid nature, not forseeing our need to drive Hummers and Ford Excursions!
  • by AnhZone ( 139289 ) on Monday October 27, 2003 @11:20AM (#7318825) Homepage
    Why do we care about prehistoric plants that turned into underground petrochemical deposits millions for years ago. I agree that cars are ridiculously inefficient, but underground oil is not one of the natural features I am worried about being disturbed. Above-ground pollution, oil spills, global warming, yes, but why cry for rotten prehistoric plants?

    • If we were to switch from burning prehistoric plants to modern ones (i.e. veg oil) then we would no longer be adding to carbon emissions by driving cars because the growing plants consume as much C02 as a car generates.

      Some people will have you believe that this is pointless because we couldn't grow enough oilseed rape or whatever. I say let's try it and find out.

      My next car will be a big, inefficient, carbon neutral monster.
    • by ianscot ( 591483 ) on Monday October 27, 2003 @11:54AM (#7319137)
      Interesting little synopsis of the usual environmental debate, your post.

      Environmentalist: We're running out, and our current wasteful practices mean we're running out fast!

      Apathetic response: Who cares about a bunch of dead plants anyway?

      The answer being, as we (literally) burn through these resources, they not only produce waste that endangers the place we live, they also become more scarce -- leading to the places that have the dead plants, in the form of oil, receiving quite a lot of value for what's left. Scarcity and value, see? Take a look at the extreme wealth of Saudi Arabia's ruling family, examine the Wahaabist faith they've backed using that wealth, all the result of a scarcity of these old dead plants in the world, and then tell me -- is it a potential problem for oil to be the scarce resource we're relying on? Do we want to continue to use inefficient methods of blowing through the oil we've got left, making it more scarce, increasing the upheaval caused by things like Opec's production targets? Or not?

      So, see, when environmentalists are worried about this, it's not some tree-hugging lovey-eyed thing on their part, it's self-interest. Similarly, when scientists fret over an oncoming mass extinction, they're worried because no previous mass extinction has allowed the currently dominant group of species to continue in that role. It's not that they're only worried about black-footed ferrets or whatever; they also see that human survival is at stake.

      That being the point. Not that "really big numbers" is necessarily the best argument, but human survival is the point.

    • by exp(pi*sqrt(163)) ( 613870 ) on Monday October 27, 2003 @12:05PM (#7319248) Journal
      The point is we should celebrate. Those plants died believing that that was all there was to their existence. But millions of years later the energy they stored during their lifetimes has found a new purpose. Maybe millions of years after you die you'll find a purpose too. I think it's wonderful.
  • Better than that (Score:5, Insightful)

    by cybercuzco ( 100904 ) on Monday October 27, 2003 @11:20AM (#7318827) Homepage Journal
    this still makes you think about how inefficient our cars are.

    Its even better than that! Internal combustion engines are only about 25% efficient, so for every ten gallons of gas you put into your car, only 2.5 gallons are actually used to propel you forward, the rest is just used to heat up the engine and exhaust.

  • by TopShelf ( 92521 ) on Monday October 27, 2003 @11:20AM (#7318829) Homepage Journal
    That certainly explains the foul smell I can't get out of the seats...
  • by Xiver ( 13712 ) on Monday October 27, 2003 @11:20AM (#7318830)
    I read an interesting article at []. Technological savvy could turn 600 million tons of turkey guts and other waste into 4 billion barrels of light Texas crude each year.

    I think this is a huge step in the right direction, I'll be very interested to see what happens once the plant is online.

  • Comparisons? (Score:3, Interesting)

    by confu2000 ( 245635 ) on Monday October 27, 2003 @11:20AM (#7318833)
    Anyone want to take a stab at how much a horse eats per mile? I guess to be fair, you'd probably want to multiply it by 4 at least. Even then it's only 4 horsepower versus like 100-150 in your standard economy car.
  • by Wyatt Earp ( 1029 ) on Monday October 27, 2003 @11:20AM (#7318835)
    "The research paper also mentions that everyday, we are using the fossil fuel equivalent of all the plants growing during a whole year just for our cars."

    If there's 600,000,000 of plants and plant material out there to burn in fossil fuels...and we burn a years worth of it a day. And you divide 600 million by 365...that gives us 1643835 years worth of fossil fuels.

    A much more optomistic projection that even the Skeptical Environmentalist!

    I'm going to go drive my 5.7 liter Chevy truck around then just for the hell of it.
  • Inefficiency? (Score:5, Insightful)

    by worst_name_ever ( 633374 ) on Monday October 27, 2003 @11:21AM (#7318841)
    Even if these numbers are too large, this still makes you think about how inefficient our cars are.

    I agree that regular gas-powered cars could be made more efficient, but don't the numbers above point more towards the "inefficiency" of the prehistoric plants --> crude oil deposits process?

  • If it *is* plants (Score:5, Interesting)

    by HarveyBirdman ( 627248 ) on Monday October 27, 2003 @11:21AM (#7318847) Journal
    There's an idea that some oil comes from deeper sources, and has an abiogeneic origin. There are hundreds of wells drilled more than 5 km deep, below the levels of prehistoric plants (what is called "basement rock"), and they are still productive.

    Here's a starter link: Link []

    • Re:If it *is* plants (Score:4, Informative)

      by Greg151 ( 132824 ) on Monday October 27, 2003 @11:38AM (#7319011) Homepage Journal
      Thanks for bringing up Thomas Gold. There is really little evidence to go along with the fossil theory of petroleum, and increasingly more to support Thomas Gold. See this link []
      • I'm not sure I buy the theory yet myself. I've read Deep Hot Biosphere, and he does have some compelling stuff on his side. It's one of those fringe theories that just might pan out.

        I have to think the environmentalists would be opposed to this idea. The idea that we really have a potentially *unlimited* supply of oil could keep them up at night with visions of the 28-wheel Hummer H5. :-o

        • Hey Harvey, if you read the Wired article, Mr. Gold refers to finding oil 5 miles down through Granite shield material in Sweden. That sounds like a whole lotta proof to me. It shouldn't be there, if it did derive from fossil material.
    • Re:If it *is* plants (Score:3, Informative)

      by mikerich ( 120257 )
      There are hundreds of wells drilled more than 5 km deep, below the levels of prehistoric plants (what is called "basement rock"), and they are still productive.

      Basement usually refers to ancient metamorphic or igneous rocks. AFAIK there are no productive wells in such areas.

      Sedimentary rocks can be pushed down beyond 5km in so-called downwarps. In fact they are almost essential since the oil formation process requires the source rocks to enter the so-called 'oil window'. As rocks get buried, the temp

      • by Tony ( 765 ) on Monday October 27, 2003 @01:42PM (#7320061) Journal
        "Robert O. Russell, a wellsite geologist at the first well in North America (at Fort McMurray, Alberta, Canada) drilled into crystalline basement granitic shield rocks for the express purpose of commercial hydrocarbon exploration, has pointed out that there are more than 400 wells and fields worldwide, both off-shore and on-shore that produce or have recently produced oil from igneous rocks." (Quoted from here [])

        There is really no evidence supporting an organic origin of petroleum. At one time, it was the best explanaition we had; now, with oil drilled from beneath basement rock, and from 3B-year-old sandstone, there is no longer any reason to just assume organic origin. Too much evidence points to non-organic origins.
  • Does it say (Score:5, Insightful)

    by Kohath ( 38547 ) on Monday October 27, 2003 @11:21AM (#7318848)
    Does it say how many tons of plants have existed in the last billion years or so?

    I bet it's a lot.
  • by Derek Pomery ( 2028 ) on Monday October 27, 2003 @11:25AM (#7318883)
    But also about inefficiency of natural fossil fuels.
    Key Fact.
    Since only about one-10,750th of the original carbon in ancient plant material actually ends up as oil, multiply 4.14 kilograms by 10,750 to get roughly 44,500 kilograms of carbon in ancient plant matter to make a gallon of gas.

    google cache of old-news biofuel breakthrough []

    Note they are claiming they can eliminate dependance on oil importation with agricultural waste alone. No other cultivation necessary.
    And the point is. Once we use the biofuels, we are in the carbon cycle. No more pumping carbon out of the earth.
  • by Saint Stephen ( 19450 ) on Monday October 27, 2003 @11:26AM (#7318887) Homepage Journal
    Gee, that means 1,000,000 years of plants will only last us 2,737 years! And we all know the prehistoric period wasn't measured in hundreds of millions of years!

    [For the record, I support Hydrogen so we can tell the Arabs and Environmentists to go jump in a lake and quit bugging me.]
  • Prehistoric Plants? (Score:3, Interesting)

    by phorm ( 591458 ) on Monday October 27, 2003 @11:27AM (#7318893) Journal
    While I do agree that currently vehicles are inefficient and that we are eventually heading towards insufficiencies in our supplies of fossil-fuel, one must also consider the vegetation of the eras that became the fossil fuels of today. From what I can gather, many plants were rather humongous in comparison to today. I mean, if say during the period of dinosaurs, plants had to be big enough to feed a pod of 10-15 meter behemoths, I'd say we had a lot of vegetation going at that time. Forget how many plants it takes to power a car, how much did it take to fuel a dinosaur?

    And besides, aren't fossil-fuels the product of not only plants, but animal-life as well? I could be wrong on this one, but I think everything was part of the good ol' life-to-petrol cycle.
  • by OverlordQ ( 264228 ) on Monday October 27, 2003 @11:28AM (#7318902) Journal
    rods to the hogshead was bad enough, now we got Plant ton/(km|mi)!? WHEN WILL IT END!?
  • So? (Score:3, Interesting)

    by SlamMan ( 221834 ) <squigit AT gmail DOT com> on Monday October 27, 2003 @11:29AM (#7318912)
    What's the big deal? Its not like this 4 tons of dead plants are doing anything else if I'm not using it.
  • by Fnkmaster ( 89084 ) on Monday October 27, 2003 @11:30AM (#7318928)
    That's right, there are great solutions out there that are far more efficient. But the unfortunate reality right now is that the economics of pumping shit out of the ground is very, very hard to compete with. The cost basis of oil (formed mostly by transportation, corruption and cronyism) vs. any harvested biological feedstocks used to make ethanol or biodiesel may be closer to competitive these days, but it's unlikely that the harvested feedstocks will ever win out by a large enough margin to encourage the capital investment necessary to switch over the huge established infrastructure without substantial government intervention.

    No, I'm not talking about corn ethanol here, so please stop the silly arguments about how ethanol is inefficient - making it from corn is just silly. There are lots of cheap, far more easily harvested cellose-based plant products that can be broken down with slightly more effort into ethanol, and could provide us with a cheap, plentiful, and substantially more efficient means of storing and transporting biological energy to power our big ole' gas guzzlers.

    This is a substantially more realistic and cost effective solution than hydrogen, and it doesn't require us to build massive amounts of new infrastructure (just a limited number of bioethanol plants) or a totally new kind of transportation and distribution network to handle hydrogen. Ethanol is stable, easy to transport, and holds up quite well to most abuse (well, except the drinking kind). It still takes a lot of cellosic material to make a gallon of bioethanol, but it's a lot less than went into that gallon of gas - it's just that the input of biological material happens in the here and now instead of millions of years ago - so we have to bear the cost ourselves. But it's renewable, predictable, and would remove the sick political imperatives behind the distribution and availability of fossil fuels. As an added bonus, no more terrorists.

  • by Keighvin ( 166133 ) on Monday October 27, 2003 @11:36AM (#7318988)
    Plant matter is quite ineffecient for producing heat, especially when taking into consideration that 80% of a plant's mass is taken up by water - last I was made aware, water is not a particularly good source of fuel unless you can get the hydrogen out.

    Alternatively, plants can be refined to a better state of consumption, i.e. vegetable oils for diesel engines:
  • by prgrmr ( 568806 ) on Monday October 27, 2003 @11:42AM (#7319032) Journal
    Even if these numbers are too large, this still makes you think about how inefficient our cars are.

    Yes, I agree that today's internal combustion engines are ineffienct. However, this is a classic apples-to-oranges comparision gone bad. The prehistoric plant matter in question went through a whole heck of a lot in its journey to becoming crude oil. As another poster already pointed out, a non-trivial part of that transformation was loss of most of the water in the plants, and hence much of their volume. That means his figures for the weight are already suspect.

    It would be much more proper to first examine the plants-to-petrol transformation process, and comment on how efficient that process is first, then the petrol-to-MPG process.

    This is simply more cargo cult science [], and we can and should do better, IMO.
  • by pulse2600 ( 625694 ) on Monday October 27, 2003 @11:43AM (#7319043) many Libraries of Congress is that?
  • by dpbsmith ( 263124 ) on Monday October 27, 2003 @11:44AM (#7319049) Homepage
    ...don't worry, we'll soon have energy too cheap to meter. We'll unleash the limitless, endless, bountiful power of the peaceful atom to provide an inexhaustible supply of energy for all mankind.

    A single aspirin-sized pellet of uranium will provide Mr. and Mrs. America with enough power to run their car for a lifetime. And soon, the peaceful atom will provide a propulsion source that will make family helicars practical and affordable.

    Scientists expect this to happen in a few short decades--perhaps before the end of the sixties.

    At least, that's what the science teacher said when I was in junior high school.
    • The sad thing is, the science teacher was absolutely right.

      Uranium, pound for pound, will give you more energy in a nuclear reaction than almost any other substance will give you through combustion. The reason why the Atomic Age never really happened is two-fold: Political and Economic.

      Political, because people are scared of nuclear energy. They get scared when a proposal for nuclear power comes to town. Never mind that coal, oil and natural gas power facilities have killed 10 to 100 times the people that
  • by Jay Bratcher ( 565 ) on Monday October 27, 2003 @11:59AM (#7319191) Homepage
    Rather, it says that fossil fuel, and the process it goes through to get to the point that it is useable for a fuel (including the several thousand years it spends underground), is inefficient. The same cars running on grain alcohol use considerably less, as far as I know - I can't imagine 4 tons of corn being used to produce a gallon of grain alcohol...
  • by Helevius ( 456392 ) on Monday October 27, 2003 @12:08PM (#7319291) Homepage
    I don't see the point of this post. We will never run out of oil. Why? Economics. Assume oil began to become scarce. No new supply is replacing the oil taken from the ground. Assuming fixed demand, the price of oil would rise as the supply diminished. (If demand rose, the price would rise even more.)

    As prices rise, alternatives to oil become financially viable. Suddenly fuel cells or wind power or any other technology currently more expensive than oil looks attractive to investors. Those who can afford oil buy it, while others turn to the alternatives. Assuming no new oil is discovered (to address the supply issue), eventually no one cares about oil as everyone has transitioned to other forms of energy. The remaining oil sits in the ground unused.

    Of course this adjustment must take place over the mid- to long-run. Short-term adjustments are called "oil shocks," such as we had in the 1970s or during the early days of most recent wars.

  • by HardCase ( 14757 ) on Monday October 27, 2003 @12:09PM (#7319297)
    It's kind of interesting, as trivia goes, but what of it? Given that the large amount of lawn clippings, leaves and such that I put into my composter ends up as a much smaller mass, I'm not surprised that some massive amount of vegetation was required to end up with a gallon of gas.

    "Staggering"? Not really. Most of what used to be a plant was water. And if, as the article says, only 1/10750th of the carbon from the plan makes it to become oil, the rest served as fertilizer (to help other plants grow and become oil (and more fertilizer)).

    If the idea is to point out that gasoline engines are inefficient, well, duh! If the idea is to point out that oil is an unsustainable energy source, well, duh! If the idea is to point out that we need to develop new energy technologies, well, duh! But "98 tons of plants per gallon" is kind of a red herring. Plants die, the water evaporates, the plant mass decomposes and serves as fertilizer and a little bit, over a long period of time, ends up as oil. As a system, it's somewhat inappropriate to pick out a single element the way that the author of this paper did. Yes, it did take quite a large amount of plant material to make a gallon of gas, but if more of the plant material turned into oil, then less would have been available to enrich the soil and provide for the growth of new plants. The numbers are interesting, but they only tell part of the story.

    Oh, and to add to the conclusion of the article, the author left out nuclear power from "other technologies".


  • by kindbud ( 90044 ) on Monday October 27, 2003 @12:10PM (#7319308) Homepage
    The steel used to build your car's frame and body was produced in a supernova over 5 billion years ago. Only a tiny fraction of the energy generated by fusing at least 4 solar masses of hydrogen went into the production of the iron, chromium and carbon that was used to make the steel. A whole solar system was likely destroyed in the process.

    Automobiles are far more inefficient than even this article implies.
  • Cars inefficient? (Score:3, Insightful)

    by misleb ( 129952 ) on Monday October 27, 2003 @12:13PM (#7319324)
    Seems to me that "4 tons of plant material per mile" speaks more to the massive amounts of energy that modern technology and societies require than to its relative (in)efficiency. The average internal combustion engine is, what, 25% efficient? Thats not terribly bad. Lets say you made it 100% efficient. You'd still be using the energy equivilent of 1 ton of plant material per mile. Numbers like this really put into perspective the feasability of switching to renewable sources of energy on a global scale. Can we really expect to generate the energy equivelent of one years global plant growth every day from diffuse sources such as the sun, wind, and ocean? And that is just for our cars. I think it is safe to assume that as we increase efficiency we will also increase total consumption. There are a whole lot of people in teh world that don't own cars, but would love to...


  • by n-baxley ( 103975 ) * <nate&baxleys,org> on Monday October 27, 2003 @12:27PM (#7319445) Homepage Journal
    It also took millions of years. However, since the dead plants can't really be used for much else, and we don't since the "processing" time has alread elapsed and the end results are ready for "consumption", then the production process from live plant to oil is already 99% completed. We're just here to pick up the end result.
  • by fygment ( 444210 ) on Monday October 27, 2003 @12:34PM (#7319497)
    ... though perhaps that wasn't the intent of the article. Although perhaps blown out of proportion, the article highlights the sheer amount of biomass required to generate fuel. It is doubtful, except in niche markets, that there is a will and a way to convert adequate amounts of agricultural resources (incl. the "waste") over to biofuel production sufficient to meet our current (and future) fuel needs. It seems the dead plants prove the point.

  • by dentar ( 6540 ) on Monday October 27, 2003 @12:35PM (#7319506) Homepage Journal
    ...not on your life!!

    My PREVIOUS car got 35MPG on the highway and had plenty of power. They don't make cars like that anymore..

    Congress, with all its lip-service about ending our dependence on foreign oil, THIS YEAR, voted DOWN a bill requiring car companies to adhere to higher mileage standards.
  • by blair1q ( 305137 ) on Monday October 27, 2003 @12:37PM (#7319525) Journal
    The inefficiency isn't in automobiles, as they are something like 30-50% efficient at retrieving the chemical-bond energy from gasoline.

    The inefficiency is in the production of oil from dead plant matter. Oil is one of the lesser byproducts of decaying vegetation undergoing geological stresses. Coal is much more plentiful. And then gasoline is only about 45% of the matter in crude oil. For each gallon of gas you get 1.2 gallons of methane, kerosene, tar, paraffin, etc.

    So don't blame Otto, blame Gaia.
  • by msheppard ( 150231 ) on Monday October 27, 2003 @12:39PM (#7319533) Homepage Journal
    Maybe the PLANTS should work on their efficency of converting sunlight to gasoline. How much sunlight goes to waste?

    Won't someone think of the children?

  • by guacamolefoo ( 577448 ) on Monday October 27, 2003 @12:41PM (#7319557) Homepage Journal
    A staggering 98 tons of prehistoric, buried plant material is required to produce each gallon of gasoline we burn in our cars, SUVs, trucks and other vehicles.

    Next thing you know, they'll be saying that it takes hundreds of tons of hydrogen to fuse to allow a solar powered car to drive a mile. How wasteful!

  • by akuzi ( 583164 ) on Monday October 27, 2003 @01:24PM (#7319892)

    There are many alternative theories for petrolium formation, many are 'abiogenic' theories that say that 'fossil fuels' are actually primordial, that have existed since the Earth was created.

    For more info read see this [] and "The Deep Not Biosphere" by Thomas Gold of Cornell university.

  • by Harik ( 4023 ) <> on Monday October 27, 2003 @01:42PM (#7320052)
    Assuming that it _DOES_ take 98 tons of plant material to produce one gallon of gasoline, they're still wrong. Gas is just one of the things that comes from crude oil. Think they just throw the rest away? Nope. It all gets used: Grease, Fuel-grade oil, Diesel, whatever. There's a market for every grade. How many plants does it make for a gallon of crude? And how much of that becomes gasoline? That's the real number that matters.
  • by p7 ( 245321 ) on Monday October 27, 2003 @01:58PM (#7320194)
    Recent studies show that Solar Energy is grossly inefficient. Scientists at a leading University have determined that solar powerer 100 watt light bulbs use 590,000,000 tons of hydrogen for every hour they are on. Scientists do say that they efficiency will get better as we cover more and more of the earth with solar cells, however they doubt we will ever get to the equivalent efficiency seen with the 78 tons of plant matter to a gallon of gasoline. These results have led many to question the use of solar power.
  • by FearUncertaintyDoubt ( 578295 ) on Monday October 27, 2003 @02:03PM (#7320228)
    "We would have to choose between our rain forests and our vehicles and appliances."


  • by Pedrito ( 94783 ) on Monday October 27, 2003 @02:04PM (#7320235)
    You know, a lot of people have been complaining about the slash and burn of the Amazon rain forest, but I think people are really just thinking ahead and trying to make more oil. You guys are so short-sighted.
  • by RockyMountain ( 12635 ) on Monday October 27, 2003 @04:02PM (#7321382) Homepage
    Even if these numbers are too large, this still makes you think about how inefficient our cars are.

    Several posters have countered with the suggestion that mother nature is inefficient, using so much plant material to make so little fuel.

    But, both the "cars are inefficeint" and "nature is inefficient" arguements miss one important point: That the huge amount of biomass was spread out over millions of years of growth, with the vast majority of the material being recycled from one growth generation to the next. Obviously, just by virtue of the fact that a gallon of petrol weighs a lot less than a small forrest, we must conclude that most of the material didn't become fuel. Most of it became fertilizer/compost, and fueled the next generation of growth.

    Adding up the mass of all these generations of plant growth is really just repeatedly counting the same material over and over.

Sigmund Freud is alleged to have said that in the last analysis the entire field of psychology may reduce to biological electrochemistry.