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Vinod Khosla Talks Ethanol 430

Posted by timothy from the slurred-speech-red-eyes dept.
IamTheRealMike writes "Vinod Khosla, venture capitalist and co-founder of Sun, has a new obsession these days. Ethanol is the fuel touted by many as an alternative to dwindling oil stocks, but is it all it's cracked up to be? Whilst Khosla is an avid supporter of ethanol as an alternative fuel (video link) his optimistic views have been rigourously challenged by Robert Rapier, an oil industry insider who is also engaged in a quest to discover alternatives. Recently the two debated via phone the merits of an ethanol economy, and Mr Rapier has now written up a report of the debate. What will be powering our cars 10 years from now?"
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Vinod Khosla Talks Ethanol More

Vinod Khosla Talks Ethanol

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  • What will be powering our cars 10 years from now? (Score:5, Insightful)

    by Anonymous Coward on Monday July 31, 2006 @01:16PM (#15818924)
    Probably oil.

    Still.
    • If Congressman Fred Upton has his way, our engines will be running on 10% ethanol by 2012. This is a good policy that deserves consideration.
      • Whenever someone pushes ethanol that hard, they're really pushing for corn subsidies. If he starts talking wood chips or sawgrass, that might be something worthwhile, but as it stands it's just another pork project.
    • I guarantee you that oil will be used by a vast majority of the worlds vehicles by 2016, however there will be a few alternative fuel vehicles on the road *imho* at that time. What they are.. I have no idea, because if there's one thing history has shown us, that when we try and guess and tech advances.. 9 times out of 10 we look like utter fools in retrospect.
    • Oil? Nope. My prediction: Fred's big feet. (think "Flintstones")

      On a positive note, all those oil company bigwigs'll be turned into Al Bundy-style shoe salesmen...

  • Ethanol powered... (Score:3, Funny)

    by BronsCon ( 927697 ) <social@bronstrup.com> on Monday July 31, 2006 @01:17PM (#15818936) Journal
    Ethanol powered drivers are already behind the wheel of many American vehicles. This seems more of a problem than a solution. Though the Fred Flintstone Engine would seem to work well, especially with enough ehtanol in your system that you don't notice that you just lost all the skin on your feet at the last red light.

  • Look, this is simple. (Score:5, Insightful)

    by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Monday July 31, 2006 @01:18PM (#15818944) Homepage Journal

    Ethanol has shitty energy density. The solution, if you are using liquid fuel, is to use biodiesel for diesels and butanol for gasoline engines. You can run E95, 95% ethanol and 5% gasoline, in diesel engines just by increasing compression and changing fuel delivery (not sure if it's increase or decrease; I'd guess increase.) You can run butanol in gasoline engines without modification, though low-compression engines may need to have their timing advanced since butanol has a higher octane rating than gasoline, IIRC.

    Regardless what we make biofuel out of, the most important point is that it not be topsoil-based. Agriculture is the most destructive technology ever unleashed upon the Earth by mankind. Hydroponic crops make dramatically more sense as fuel feedstocks.

    • The problem with biodiesel is that it congeals at temperatures that are commonly found in the winter in the united states. Unless you don't mind walking everywhere, you need a different solution. You can, of course, use a little bit of biodiesel to help reduce the amount of fossil fuel burn.

      • Even if there is no solution to that issue, that only rules it out in some parts of the country, during some parts of the year. Same worldwide.

      • Actually, gas or kerosene is usually added (with what, no more than 10%?) to prevent that problem. Likewise, fuel additives are already available (have been for a very long time) which serve the same purpose. These additives are common place for certain categories of planes where their cold operating environments may cause freezing and gel concern.

         

      • Re:Look, this is simple. (Score:5, Interesting)

        by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Monday July 31, 2006 @01:42PM (#15819215) Homepage Journal
        The problem with biodiesel is that it congeals at temperatures that are commonly found in the winter in the united states.

        Very true. There are three solutions to this problem.

        The first is a fuel stabilizer added to the fuel. This can be a toxic solution, but is not necessarily. One possibility is (as you say) to thin it with petrodiesel. Another is to thin it with alcohol, which as we know is already known to be run in diesel engines with only minor additive and modifications. A modern TDI diesel with high compression (One report I read featured vehicles running at 23:1 compression pre-turbocharging, which is fairly high except that some of your old school mercedes diesels are 22:1 anyway) but I'm not sure if an additional additive would be necessary to prevent the alcohol and biodiesel from interacting somehow.

        The second is some sort of heating mechanism. For instance, a small, electrically-heated fuel reservoir could provide enough fuel to start the vehicle, and operating heat could be used to heat the fuel tank. This does add some weight and complexity but it could be a working solution. This could even be a subreservoir inside the fuel tank, that the driver is not necessarily even aware of.

        The third solution is basically just a modification of the second, in which we have a completely separate fuel system. We fill this with petrodiesel and start up on it. Even petrodiesel requires heating at very low temperatures, of course, but we can use an additive with this fuel, and not feel too bad about it almost regardless of what that additive is, because we're only using it to come up to temperature.

        I still believe that butanol has the most promise, however. To quote from butanol.com (a business, mind you):

        July 14 to August 15, 2005 was the first run across the Nation on 100% Butanol. Demonstrating to the public that there is an alcohol made from corn that replaces gas right now if we had it. The sooner we start making Butanol the sooner you will see it in your tank and go down the road - it works. The '92 Buick Park Avenue got 24 miles per gallon on butanol with no modifications - normally gas is 22 mpg. That is a 9 % increase. In ten states Butanol reduced Hydrocarbons by 95%, Carbon monoxide to 0.01%, Oxides of Nitrogen by 37%, this in a 13 year old car with 60,000 original miles. It runs great up hill and across the deserts. Let's make more.

        The primary reason is that it's a direct replacement for gasoline, and even at current prices it's not dramatically more expensive than gasoline. Most butanol is currently made from petro sources, but (again, as per the front page of butanol.com) "The historical ABE fermentation technology produces a variety of fermentation products. The ABE process uses bacteria to produce Acetone Butanol and Ethanol. This fermentation process yielded a 6:3:1 ratio of Butanol, Acetone and Ethanol".

        Thus the biggest problem with this process is "what do we do with the acetone"? :)

        (The ABE process was first used to make chemicals for TNT.)

        The best part is that the process works on any biological material, the only thing that changes (based on how tightly the constituent parts are bound to each other) is how long it takes to break down. All of our organic waste could simply be ground up into mush (whatever isn't already) and fed into reactors for this system.

        Well, actually, the best part is that it's energy-dense, cleaner than gasoline, and works in gasoline vehicles without modification.

      • Re:Look, this is simple. (Score:2, Funny)

        by Anonymous Coward
        Don't worry, global warming will solve that.
    • you don't need foodstock to create ethanol, you can use waste cellulose as a more ecologically friendly source of ethanol. Wiki article [wikipedia.org].

      And as far as biodiesel gelling in cold temperatures (as another poster points out), you don't have to have 100% biodiesel all the time. You can use a coal-based fuel oil/biodiesel mix (not ideal, but better than 100% crude oil diesel) or you can mix with alcohols to change the properties of biodiesel as needed.

      • Hydroponic crops make dramatically more sense as fuel feedstocks

        you don't need foodstock to create ethanol, you can use waste cellulose as a more ecologically friendly source of ethanol. Wiki article [wikipedia.org].

        If you like wikipedia so much, maybe you should use it to brush up on your basic vocabulary [wikipedia.org] before you try to comment on this subject. You positively, absolutely require feedstocks to produce any kind of fuel.

        It makes dramatically more sense to make butanol out of that stuff than biodiesel. There is l

    • It's decrease.

      Diesel engines have VERY high compression (ever hear a jack brake on a truck?) (in the 14-18 :1 and higher range If I am not mistaken)

      Gasoline (and alcohol) explode (detonate) unpredictably at these compression levels (engine knock)

      Remember there is no spark introduced in a diesel, it's the compression that ignites the fuel/air mixture.

      Today's (low octane, no lead) pump gasoline will start to detonate at around 9.5:1 compression in reasonable ambient temperatures.

      • Yes yes, he said impatiently, I know all about how both diesel and gasoline engines work. I own a 1981 MBZ 300SD. I also have a 1989 Nissan 240SX and a 1993 Subaru Impreza at the moment. I think the Suby is car #12 or so. The impreza in particular specifies only 87 AKI fuel, even though it has 9.5:1 compression; it's got a knock sensor so it can retard the timing. That results in lower fuel economy, but once the RPMs get up there, it can bring the timing back up, so I'm only lugging on hot days and under

  • Biodiesal? (Score:2, Interesting)

    by TheGreatHegemon ( 956058 )
    I myself support Biodiesal as an alternative fuel - just so much more 'waste' areas could be used. (Even LITERALLY! Human waste could be used) Clearly, there are still limitations to it, though.

    • Re:Biodiesal? (Score:3, Interesting)

      by drinkypoo ( 153816 )

      I myself support Biodiesal as an alternative fuel

      I myself support an improvement in American public education. In particular, spelling and grammar are areas which desperately need to be addressed.

      just so much more 'waste' areas could be used. (Even LITERALLY! Human waste could be used)

      If you're going to be using poop, it makes much more sense to make butanol, which is made by bacteria, instead of biodiesel, which is made through a cracking process.

      You could also run the poop into a pond, and gr

      • Oceanic algae produces something like 85% of the world's oxygen and is dying off rapidly due to pollution and climate change.

        If pollution kills algae, how the heck does this [csmonitor.com] work?

        • If pollution kills algae, how the heck does this work?

          You can find the answer in the article you linked, without even reading very much of it:

          If he could find the right strain of algae, he figured he could turn the nation's greenhouse-gas-belching power plants into clean-green generators with an attached algae farm next door.

          The right strain of algae. Not just any strain, the right strain. In particular, not the kind of strain that's dying off in our oceans.

          But, nice try. Thanks for playing. Pl

  • This is my day job (Score:5, Insightful)

    by Ignignot ( 782335 ) on Monday July 31, 2006 @01:21PM (#15818967) Journal
    I'm at my work right now, where I am employed as an energy analyst. It is the opinion of every single person in the industry that there is no real possibility of replacing gasoline with ethanol. It would take the entire corn harvest of the United States to make that much ethanol, not even counting how much ethanol you would have to burn to harvest the corn. We will continue to burn gasoline until it becomes so expensive that people use alternate transportation, or until we all die in some horrible war. The whole ethanol thing is just another wall street fad that's brought in a bunch of suckers.

    • Re:This is my day job (Score:3, Interesting)

      by lawpoop ( 604919 )
      My understanding is that Brazil already uses ethanol with almost half its fleet, and is closing in on self-sufficiency as far as their energy needs. They do this by using sugar cane as a source of ethanol instead of corn, because sugar cane gives a higher yield of ethanol than corn.

      Could the US grow enough sugar cane in its more tropical parts? Aren't there other crops besides corn and sugar cane which are oily enough to produce ethanol economically? Say, switch grass or hemp?

      • For making ethanol, you don't want "oily", you want sugar or cellulose or starch (depending on the process). For biodiesel, you want oily.

      • Sugar beets are also a viable source for sugar-based ethanol. Almost any high-sugar plant is a potential source. The question becomes how energy-dense are they.

        Ethanol should just be one option to help us move away from petroleum. As other technologies mature (e.g. more efficient solar, better battery technology), we should be able to move away from combustion engines for most applications (perhaps except as backup).

        I'm honestly surprised that we (as a society in the U.S.) have not gotten over our nu
      • My understanding is that Brazil already uses ethanol with almost half its fleet, and is closing in on self-sufficiency as far as their energy needs.

        If you actually, you know, read the article you'd know that according to BP's research (and of course, they could be manipulating the figures) Brazil actually only gets 10% of its energy from ethanol. A large part of its energy independence is domestic oil production.
      • Brazil has a surplus of cane-based ethanol to sell us, any time we want to drop the protective tarriff on anything based upon sugar cane (currently US$0.56/gallon, if I recall correctly). They have this surplus because they no longer need as much ethanol as they thought they did... Since they discovered several major domestic source of oil over the past 10 years.

        We aren't "raping" Brazil for its "abundant" ethanol for the same reason CocaCola tastes like crap in this country, compared to countries that do

      • Re:This is my day job (Score:3, Insightful)

        by thue ( 121682 )
        Could the US grow enough sugar cane in its more tropical parts? Aren't there other crops besides corn and sugar cane which are oily enough to produce ethanol economically? Say, switch grass or hemp?

        Don't forget that Americans have hummers - They use way more oil per person than Brazillians, and probably anybody else on the planet.
    • The engineers talk about Energy Return on Investment (EROI), the ratio between energy output and energy input. In the case of corn ethanol, it's pretty low, about 1.25:1. You get 1.25 units of energy out for every 1 unit of energy you put in, and for corn farming, the energy inputs will be fossil fuels. Ethanol from sugar cane has a much higher EROI. I've heard as high as 8:1, but I haven't seen the studies. If it's true, sugar cane ethanol would definitely be worth it. Then there's the more exotic processe

      • You have to be careful when looking at such figures - some of them include the solar energy input as part of the "input" side of the equation, some of them make unwarranted assumptions about how far you have to transport items, some of them don't look at the byproducts as being anything but waste, nor look at what might have otherwise been waste being used in the process.

    • It is the opinion of every single person in the industry that there is no real possibility of replacing gasoline with ethanol. It would take the entire corn harvest of the United States to make that much ethanol

      The whole ethanol thing is just another wall street fad that's brought in a bunch of suckers.

      Why do you assume that corn is the only possible feedstock that can be used to make ethanol? Yeasties don't care about the source of the simple sugars.

      You can extract the sugar for grain to make ethanol and f

  • Diesel is the future (Score:3)

    by MemoryDragon ( 544441 ) on Monday July 31, 2006 @01:24PM (#15819001)
    not the fuel itself but its engines, normal diesel engines with slight alterations can run on grease, fry fat, and a lot of other natural substances, why this potential has not been tapped more
    is beyound me.
    • Why not run on fry fat? Well, for the large percentage of the American population that works in fast food/restaurants/kitches, the idea of smelling that burning grease while they are off the job, too, is just unbearable.

  • Um ethanol, oh you mean (Score:3)

    by Tweekster ( 949766 ) on Monday July 31, 2006 @01:26PM (#15819019)
    the largest cause of gas prices being so high? Oh yeah that stuff.

    The US imports a majority of the ethanol from Brazil for mixing with gasoline, currently their is a shortage of that garbage which means higher prices. Ethanol is a pipe dream right now, but forced down our throats. Oil prices dont help the situation, but ethanol is a major cause of gas prices right now. Not to mention the gas companies have about a 100 different blends they have to make for every state and region and even in different counties.

    The blending of ethanol with gas is not only worse for the environment, but it destroys your engine, causes a significant drop in MPG. Basicall the entire ethanol gas blend is simply a subsidy to Archer Daniels who crams that junk gas down our throats.

    Supposidly pure ethanol is much better, but the mixed stuff should be outright banned. (Ever wonder why Iowa, one of the biggest corn producers for ethanol does not have or want the blended formula).

    The US needs to stop wasting time worrying about gas taxes (and taking a nickle off the price) and get rid of mixed gas and come up with a federal standard for gasoline. Enough of the, 5 mile difference equaling different gasoline formula.
    • You are right about Ethanol being more corrosive. Methanol is even worse. For the most part though, Ethanol is currently being used as a replacement for MTBE [epa.gov]s. MTBEs are better than lead as an octane enhancer, but are still bad for the environment and for our health. Since Ethanol is being used instead this reduces harmful emissions from our cars, but at the expense of higher priced gas. I bet markets adjust in the long run though and reduce the price of Ethanol. The price at the pump may be a little higher

  • That's easy (Score:4, Funny)

    by Mayhem178 ( 920970 ) on Monday July 31, 2006 @01:26PM (#15819020)
    What will be powering our cars 10 years from now?

    Can you say Mr. Fusion?

  • Vinod Khosla is interested in one thing (Score:5, Insightful)

    by winkydink ( 650484 ) * <sv.dude@gmail.com> on Monday July 31, 2006 @01:26PM (#15819023) Homepage Journal
    making money.

    He's a VC. He sells you on hype. You buy the stock of the companies that he invests in early. He cashes out at or shortly after IPO. He couldn't care less what happens to you afterward.

    The only reason Vinod is interested in ethanol is because there is money to be made. For him.

    Period.
    • And how does all that make Robert Rapier not a shill for the oil industry?

      Even if switching to ethanol or biodiesel meant the same cost per mile as gasoline is now, I'd rather be using domestically produced renewable resources instead of pumping money into the region that gave us televised beheadings and 9/11.
    • Money. For his oil company reps.

      He works for the oil industry. I read that summary, which was surprisingly matter of fact as to what the viewpoints were, but it's clear he has a pro-oil viewpoint.

      Using precious third world children going hungry as an argument against using corn as fuel? Wow that's stupid, didn't we just have a World Trade Summit where the fundamental argument was over first world countries killing third world farming operations with subsidies and the like? There's an oversupply of food in t

  • Asking the Wrong Question (Score:2, Insightful)

    by Anonymous Coward
    The question we should be asking is not what will be powering our cars, but how do shift to a society that needs less cars and less fuel in general. Buying locally grown food, riding a bike, telecomutingm and forcing our city governments to make our cities less car-dependent and more pedestrian and public transit oriented are the real answers to the issue of fuel shortage.

  • Bacteria for the win (Score:3, Interesting)

    by fudgefactor7 ( 581449 ) on Monday July 31, 2006 @01:28PM (#15819049)
    I'd wager that in the future bacterially manufactured fuels, be it ethanol, butane, or whatever new thing comes along, will all be made via bacteria on waste--or a catalyst. Hell, we've got bacteria that eats grass and poops ethanol now, and you can "grow" a batch of bacteria anywhere. All we'd need is a plot of space for a big-ass building to house the stuff in and tubes that drain the fuel into external tanks. Once Economies of Scale kicks in, it's worth the massive start-up cost.

    We'll have to do something, and bitching about energy efficiencies and densities isn't the answer, doing is.

  • It is not oil, ethanol, or [insert silver bullet] (Score:5, Insightful)

    by AHumbleOpinion ( 546848 ) on Monday July 31, 2006 @01:28PM (#15819053) Homepage
    It is not oil, ethanol, or [insert silver bullet technology here]; it is all of them together.

    We don't need a 100% replacement for oil. If we can replace 10% with one economical technology, 5% with another, and 2% with yet another then good. Repeats as additional technologies become economical. Tony

  • I wish the oil companies would think this way - (Score:3, Interesting)

    by kinglink ( 195330 ) on Monday July 31, 2006 @01:29PM (#15819074)
    "If there was no more oil. What would we use?"

    Yes there's tons of oil left in the world. There's enough for at least 20 years if we don't find more and if we find more, more than 20 years. The problem is oil companies tend to think oil is the ONLY solution. So basically according to them once the oil runs out cars will stop running. That's a good theory, except it's wrong, and we'll find a way to avoid it soon.

    But at the same time let's figure out what works. The oil company always says "that won't work" but why don't we get a reason. Is the refinery process to expensive (not meaning the cost of upgrading the refineries which is always a big number)? Is the fuel source too expensive (batteries)? Is it dangerous to contain (Plasma, Hydrogen fuel cells)? or is it too hard to come by on the scale we're talking about(nuclear power and fusion)?

    That's not to say Ethanol is the solution. Solar power is certainly not (too expensive to update cars and parts).

    Personally you have to give american and japanese car companies credit. They are at least trying to figure out the solution. European companies have basically ignored the alternatives and just switched to diesel acting like it is the solution. It too might be for the time. But at the very least we have to stop listening to the oil companies' opinions unless they are well thought out opinions. Not because they are bad people, or idiots but because they have something worth protecting (our reliance on them), and they won't just give that away or tell us "yes you CAN get energy from other sources".

  • We wouldn't even be talking about ethanol... (Score:5, Insightful)

    by Alfred, Lord Tennyso ( 975342 ) on Monday July 31, 2006 @01:33PM (#15819122)
    The first caucuses of the Presidential campaign season are always in Iowa. It's always the first news of the season, and the winner of Iowa gets huge amounts of free, positive press coverage.

    Iowa is where the corn comes from. No politician who ever expects to run for President can afford to piss off Iowa. Even if you're not running today, if it's even on your mind, you vote the way Archer Daniels Midland (the immense agribusiness that can ruin your political life in the farm belt) tells you to vote.

    We wouldn't even be talking about ethanol if it weren't for that little quirk of politics. I'd love to see some party say, "Ya know what? Let's make Iowa third rather than first and see what happens." We might still be talking ethanol, but we sure wouldn't be talking about getting it from corn.
    • That's one of the first times I remember seeing John McCain on the national stage, during an Iowa debate for the Republican nomination. He had the cajones to tell them flat-out that he thought corn subsidies for ethanol were a huge mistake and that he opposed them. He was roundly booed, but he took it on the chin and kept going.

  • BIO DIESEL (Score:5, Informative)

    by tacocat ( 527354 ) <`tallison1' `at' `twmi.rr.com'> on Monday July 31, 2006 @01:33PM (#15819123)
    • Diesel technology is over 100 years old.
    • Bio Diesel is obtained from a variety of sources, not just corn.
    • Bio Diesel is 100% compatible with any diesel engine on the market today.
    • Bio Diesel is bio-degradable.
    • Bio Diesel is non-toxic.
    • Bio Diesel doesn't blow up.
    • Bio Diesel produces less emissions than ultra-clean Dino Diesel.
    • Bio Diesel may produce less emissions than gasoline (hard to test with different engines)
    • Bio Diesel has a 2% lower energy density than Diesel. Ethanol is 30% less than Gasoline. This means you pay more at the pump to drive 100 miles.
    • Bio Diesel smells like fries, really!

    If you want to get energy independent quickly and reliably, this is the answer. If you want to create a lot of sloppy hype and get people to spend stupid amounts of money on shoddy technology that's going to be under development for decades, then micro-pile atomic reactors are a better bet than Ethanol.

    Ethanol is not perfect. It's only being hyped because GM et al are selling E85 engines. They aren't selling Diesel engines because they don't know how to make small ones. VW, BMW, Peugot, Reanault, and Mercedes all have decades of experience with small block engines. E85 is being pushed because if they pushed Diesel engines what little is left of the big three would collapse over night. Personally, I prefer Diesel. It isn't going to explode.

    • While I agree with you that biodiesel is a more attractive solution, I have to disagree with "It isn't going to explode".

      What do you think it is doing inside your engine? Pushing the piston with hugs and kisses? :) Gasoline doesn't just explode either. Under the right conditions it will, just like diesel.

      • Re:BIO DIESEL (Score:5, Informative)

        by Desert Raven ( 52125 ) on Monday July 31, 2006 @02:03PM (#15819441)
        Having worked in emergency services for a number of years, I can tell you that diesel is far more stable, and less likely to explode under normal conditions than gasoline.

        Try this: You go into your garage (door closed), and pour two gallons of gasoline on the floor. Wait 20-30 minutes, then light a match. I'll do the same thing with 2 gallons of diesel. I can already tell you the results. In your case, your garage will be reduced to splinters, if not your entire house. In my case, I'll be looking at the floor trying to figure out the best way to clean up 2 gallons of spilled diesel.
        • Too bad I've already posted on this topic, or I'd mod you myself.

          As a kid I went with my dad to his job in facilities for a large company. This company had a bank of diesel-powered generators in their basement - huge 24-cylinder beasts. On this trip there happened to be a 20 gallon bottle (think old water-cooler bottle) sitting on the floor with about 6 inches of diesel fuel in the bottom. I inquired as to whether this was a safety hazard - and then watched as a co-worker deliberately struck a match and dropped it in the bottle.

          The match fell to the liquid and was extinguished.

          As a slightly older youth I attempted to repeat this experiment - only this time with a) a plastic container, b) gasoline, and c) outside on the driveway.

          I think my eyebrows grew back within a week or two.

      • Pedantry warning-combustion engineering (Score:4, Informative)

        by Flying pig ( 925874 ) on Monday July 31, 2006 @02:42PM (#15819789)
        I can't resist it...Diesel does not explode in the engine! It burns. Lots of research has gone into developing injectors that spray the fuel into the hot compressed air in the right way, so it burns steadily without producing too high a pressure peak or burning too slowly to give good thermal efficiency. As soon as you stop injecting, combustion stops and that is how you regulate the power produced.

        Now the next useless fact: Gasoline does not explode in the engine either. If it does it is called detonation or knock and will eventually wreck the engine. Although it burns much faster than Diesel (hence gasoline engines running at much higher rpm) it is flame not explosion.

        Finally, (and this perhaps needs to be posted all over this thread because a lot of people do not understand it) ethanol has a higher octane rating than standard gasolines and has more charge cooling. As a result it can be made to burn more efficiently in an engine because the compression ratio can be raised. A modified Atkinson cycle (compression ratio lower than expansion ratio) ethanol engine can have quite reasonable efficiency, not as good as Diesel but better than lead free gasoline. And it should lose less power in the catalytic converter.

        Although the fuel tank needs to be bigger than that for a gasoline engine, because of the lower energy density, this has little to do with cost per Joule which is the important thing. It does not matter if I need 6l/100Km versus the 5 used by my Diesel engine if the cost per Joule is comparable.

        And finally finally, ethanol fires can be put out with water and reduced in intensity very quickly with water mist. It is comparable in safety to Diesel, as is recognised by the experts - marine safety agencies. The main problem with ethanol is that it doesn't really mix that well with gasoline, but this is the only way to introduce it gradually.

  • Ethanol sounds promising as a short term assistance to weening ourselves off foreign oil. Unfortunately tho, it's widely accepted by climatologists that the Ogallala Aquifer [wikipedia.org] is on course to dry up within a few short decades, and this isn't taking into account the hundreds of ethanol plants that have been developed accross the midwest recently. There will soon be a demand for corn that will create a demand for water that will no longer exist.
  • Sometimes, when you are faced with a problem which seems to have only complicate answers, it's important to step back and try to understand what problem you were trying to solve in the first place. Let's take inventory.

    * We have people and things which need to move around. That's definate.
    * We cannot instantaneously make them appear in their next location. That's definate for now.
    * We have a lot of people and things and they have to get around one another to get to where they want/need to be.

    Then there was

  • half good i guess (Score:2, Insightful)

    by Tsiangkun ( 746511 )
    Bio-diesel and ethanol only address the concerns about the supply of oil.

    They do nothing to reduce CO2 emmissions of our autos.

  • Comment removed based on user account deletion
    • I agree with you. I'm always surprised when so called progressives want to dramatically increase the tax on gasoline consumption. This only hurts those folks at the lowest end of the economic scale that have to spend a higher proportion of their income on gasoline. Take, for example, a recent immigrant who is starting his own gardening business. He has to drive his own truck to do his business. He's barely breaking even and then you double his fuel costs. Now you've taken a hard working free man, a po

  • doing the maths (Score:3, Insightful)

    by abigsmurf ( 919188 ) on Monday July 31, 2006 @01:46PM (#15819254)
    It takes 3 tonnes of corn to produce 1 ton of ethanol. The US currently produces around 300million tonnes of corn. That's 100million tonnes of ethanol.

    The US uses around 880 millionTonnes of oil. However it's important to remember that when refined, 47% is gasoline.

    I'm not sure about how the efficiency of ethanol compares but i'd estimate if has an energy density of around 75% of gasoline.

    So to meet the US' needs for gasoline, it'd need 1.5billion tonnes of corn or 500million tonnes of ethanol. That doesn't seem an unreasonable target if the US ramps up it's corn production (more demand = more money = more farms). What it can't produce it can import from agricultural nations.

  • I can not spell this out enough! Use of ethanol means 7% - 10% worse mileage for every car using it. This in turn means higher consumption! This means higher demand. In turn, we already don't have enough ethanol to go around. This in turn means lower supply. Put it all together and we are now all paying even more for fuel! To make matters worse, ethanol from corn is stupid. The only people this helps are corn growers. We are paying two or three times for ethanol from corn. On top of that, I believ
  • From yestarday's interview with Chevron's CEO David O'Reilly [sfgate.com]:

    we're focused in our biofuels technology work is how to make ethanol out of something that is already going to be thrown away, like farm waste products.

    He believe as a company that the most important source of new energy is energy efficiency and the company is investment on a number of alternative energy search. Seems quite astute for an oil man.

  • The numbers for corn are terrible (Score:3, Informative)

    by Animats ( 122034 ) on Monday July 31, 2006 @02:09PM (#15819483) Homepage

    Even the numbers from the National Corn Growers's Association [ncga.com] only indicate that ethanol from corn produces only 30% more energy than goes in. That's a poor energy return. Numbers from opponents of ethanol are much worse.

    The more promising idea, if it can be made to work, is "cellulosic ethanol". The idea is to develop bioengineered enzymes that can digest agricultural waste (straw, corncobs, sugar cane, wood chips, etc.) into something more useful. But so far, no process to do that is beyond the pilot plant stage.

  • Nice rebuttal at The Ergosphere (Score:3, Interesting)

    by rrwood ( 27261 ) on Monday July 31, 2006 @03:03PM (#15819992) Homepage
    The "poet engineer" over at The Ergosphere [blogspot.com] does his usual amazing job of responding to this.

    For those not familiar with it, The Ergosphere is an excellent blog that tackles energy related issues from an analytical/scientific/empirical point of view, neatly cutting through any associated hype. Definitely recommended for anyone with an enviro-geek mindset. :-)

    As a teaser, here's the conclusion to the article, after a lengthy analysis, complete with verifiable stats:

    In my less than humble opinion, the powers-that-be are promoting ethanol because it serves up subsidies to various interests while not threatening the status quo (oil companies). If you can make an end-run around those interests, you could improve the environment, the economy and the prospects of the average American while making a huge pile of money. Isn't that better than just being a shill for GM, the corn farmers and ADM?

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