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Science

Ethanol Not A Total Loss 78

Posted by Hemos from the refueling-the-cah dept.
blamanj writes "It has been argued that using corn-derived ethanol as a fuel costs more in energy than what is produced. However, it is being reported that a new study that calculates the energies to include processing by-products reports a net gain in energy such that every BTU of existing liquid (fossil) fuels spent produces a 6 BTU return. While this doesn't address the environmental impact of large-scale farming, it's good news for Iowa farmers."
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Ethanol Not A Total Loss More

Ethanol Not A Total Loss

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  • Who said ethanol was a "total loss?" It is probably my all-time favorite chemical.
  • According to this study, they get more energy from the ethanol than it takes to make it.

    So, you make some ethanol, then use that ethanol to make more ethanol, use that to make even more ethanol,... eventually you've got an endless supply of fuel.

    Somehow I get the impression that something's missing, like the laws of entropy.

    • Ethanol is solar energy (Score:3, Informative)

      by crow ( 16139 )
      Ultimately, we're talking about solar energy here. A plant uses photosynthesis in pulling CO2 out of the air, releasing the O2 while constructing more useful molecules out of the carbon. We then use some energy of our own to process this plant and the solar-generated molecules into a form where we can release the energy.

      So it's not surprising that if you leave out the sun, your equations will indicate that we're creating energy out of nothing.
      • Getting down to brass tacks, coil, oil, hydro- and wind power are also solar energy. In fact, the only source of energy we have that doesn't derive from our sun is nuclear.
        • I'll pick a nit and say geothermal isn't solar in origin. It's from the energy trapped way back when the Earth formed. I'm not sure exactly how much of that energy is solar in origin, but I don't think it's a lot.
          • Actually a good bit of geothermal is probably nuclear (radioactive decay). And of course solar power is nuclear. So all our energy is really nuclear power, mostly from the plant 93 million miles away. Pity we can't get a more efficient power transfer mechanism going though.
        • Oil and methane are geologic, leaking up from the huge amounts of carbon in the Earth. That's why volcanoes often emit a lot of carbon and oil fields can refill. It's also why our helium comes from methane and oil wells [accesstoenergy.com]...it's not harvested from the air, and as a noble gas it is not in many minerals, but it's cheap because it comes from the ground.

          The oil may also be indirectly nuclear. It's not from sun-powered plants. But there may be bacteria in the rocks eating carbon floating up...and the deep heat from the Earth's radioactive decay is helping give them energy.

    • Sounds like someone has been "testing" the potency a little too much..

      Now maybe these ethanol induced statments will start sounding more like marketing...

      ...Drives great, less filling
      ...It's not just for drinking anymore
      ...got mash?

      next


    • So, you make some ethanol, then use that ethanol to make more ethanol, use that to make even more ethanol,... eventually you've got an endless supply of fuel.

      Hmm. Endless supply of booze. Er, fuel.
  • "...address the environmental impact of large-scale farming..."

    I'm happy to see I'm not the only one who has seen the light regarding this practice. Large-scale farming is probably the absolute worst thing we could be doing to the environment. Monocultural plants lacking biodiversity are a haven for bacteria and virii. Growing and cutting the plants down every year pulls carbon out of the soil and launches it into the atmosphere. Tilling the soil makes it more susceptible to erosion. Irrigation reduces the availability (and cleanliness) of drinking water. Without doubt, if we discontinued farming altogether we would be better off.

    • I totally agree. Ethanol may be cleaner to combust, but the environmental impact of monoculture farming are huge. Farming techniques are getting better, but there's a long way to go.
      • I have heard that to supply the world with fuel ethanol, we would have to farm an area slightly larger than Alaska. That is ridiculous.

        A much better thing would be to farm sea kelp and decompose it to produce biogas. Sea kelp grows over a foot a day. Much better than corn. The decomposition process of course realeases methane and CO2. But the methane is utilized for fuel. The CO2 off gassing is offset by CO2 the kelp absorbs.

        Growing kelp in large areas would not harm the environment at all. Kelp forests are like the rain forests of the ocean. They provide haven for all sorts of sea life.
        • Never heard that suggestion before.
          So long as we don't overfarm the Kelp forests of course...

          The combustion of methane will of course produce mroe CO2, but this should also be offset by the kelp's growth as well.

          What about trasportation and storage of the methane though? That's going to be a tricky problem, although transporting the kelp to more local places which then extract methane would solve that in part.
        • A much better thing would be to farm sea kelp and decompose it to produce biogas.

          Why not just harvest all the (invasive species) kudzu (which also grows like crazy) and decompose *that*? Two birds with one stone.

    • Re:Indeed (Score:1, Insightful)

      by Anonymous Coward
      Uh.. Growing uses carbon. Then the plants are cut, but most of them stay in the field and are plowed under so that carbon remains in the field. The carbon which is removed is the fruit, seed, or whatever is harvested from that field.

      However, you're wrong on a little detail. Farming pulls carbon from the atmosphere. You've forgotten that plants pull C02 from the atmosphere and emit O2. All those tons of plants, whatever type the crops are, are full of chlorophyll. They use C02 to create sugars, which contain carbon. The plants become full of carbon. You know various plants contain sugar, starches, and cellulose. All of those are sugar molecules, in the terminology of chemistry.

      If you want to protect the atmosphere from carbon, harvesting stuff from farms is just what you want done. Yet you're arguing against it.

      For that matter, if your house is stick-built, all that wood in the walls is part of carbon sequestration. As long as the wood is in your walls it's not in the wild, burning or feeding creatures which emit carbon dioxide. If it gets buried in a landfill, whatever doesn't get digested into methane will stay in the ground.

      Of course, if you really want to reduce the greenhouse effect you'll have to cover the oceans and stop all that nasty water vapor.

  • There's already too much corn most years anyway. The government pays farmers to leave ground fallow. If a new market is opened for corn, it will simply mean that the acres that are now growing weeds will be growing something useful. I don't think we're talking about plowing up National Parks here.
  • Using corn oil to make ethanol for cars is a possibility, but I am more interested in using corn oil (or rapeseed, sunflower etc.) as a direct substitute for diesel fuel, like this guy is doing [veg-oil-car.com].

    Actaully I was thinking of crusing over and seeing the guy later this week - a friend an I are thinking of starting a diesel to veg-oil conversion business. If anyone else is interested in this you can email me on palfreman at ntlworld.com and we pay him a visit.

    • Diesl is cool, but it's not without it's problems. Diesel engines tend to emit a lot of acrid balck smoke. You can filter it out of the exhaust with a corresponding reduction in power output from the increased back-pressure. However, I've also read that if you put spark plugs in a Diesel engine to fire after the natural detonation, you get more complete combustion and less smoke. Is this true?
      • Diesel engines tend to emit a lot of acrid balck smoke. You can filter it out of the exhaust with a corresponding reduction in power output from the increased back-pressure.

        On the other hand due to the higher efficiency of a diesel engine. You should get less total combustion by products i.e. fewer by products per mile. So, that begs the question of what is worse, particulate pollution or higher overall pollution?

  • At last, something I know something about... (Score:3, Informative)

    by Big Sean O ( 317186 ) on Wednesday August 07, 2002 @08:40AM (#4024599)
    A few years ago I drove a car optimized for an 85% Ethanol blend. Sometimes I used plain old Gasoline, sometimes I used the 85% EtOH. As a fuel, I found it performed as well as gasoline, as least in city driving (where MPG tends to tank anyway). I did notice a decrease in MPG when I was driving on the highway, but then I just switched to unleaded.

    Using EtOH does a couple things, each of them are laudable, IMHO:
    • Creates another market for Corn. By opening another market, we might reduce farm subsidies.
    • Reduces dependence on foreign oil and reduces the need to use reserves.
    • Reduces air pollution. Specifically it reduces ozone production. That's why EtOH is used as an oxygenator during the summer months.
    • Finally, growing lots of corn improves the carbon equation. Instead of pumping up 50 million year old carbon that has been sequestered all this time, using ethanol helps make it more of a zero sum game. Ideally, you're growing (removing) the same amount of carbon from the atmosphere that you're burning as EtOH. At least that's the theory.
    In short, EtOH isn't a magic bullet, but it's definitely part of the mix.
    • I hope that's all true, but you forgot the real reason that the Bush administration supports this, but not other environmental issues:
      • A good excuse for corporate welfare for ADM.
      ADM has been getting huge tax breaks for this for years, even when it clearly wasn't good for the environment. Why? Even though ADM offcials have pled guilty [usdoj.gov] to price fixing, they still are loved in Washington since they are major donars.
    • Creates another market for Corn. By opening another market, we might reduce farm subsidies.

      If government laws were to require ethanol in gasoline, then that would simply be an indirect farm subsidies. The US likes to pretend it believes in the free market, but it obviously does not.

      • I agree that agricultural interests would mostly likely support a requirement for ethanol in gasoline, but claiming that anything the government does creates a subsidy that destroys free markets does not follow.

        I could similarly claim that obviously since the government requires that schools be built, it's subsidizing the construction industry, and that obviously because the government requires that there be power in school buildings, it is subsidizing the energy industry.

        I think the measure of market freedom would involve whether there were competition in the hypothetical market. The ethanol requirement would create a new market for corn products, and the creation of the market would not ipso facto determine whether that market were "free."

        What do you think is obvious about the creation of the market that would make it "unfree?" Maybe we are not both talking about the corn products market. What types of government-inspired demand are part of a free market or not part of a free market? In this case, I think the demand is at least as real as that for fire trucks and ambulances---the demand is for real products that can be supplied by a competetive market, and it is not like the government is simply paying the corn producers whether or not they produce corn, which is what I would consider a subsidy.

    • Finally, growing lots of corn improves the carbon equation

      What about the carbon you burn in actually producing the stuff? Diesel fuel for tractors; electricity for pumping, irrigation; energy used producing pesticides and fertilizers; energy used in the refinerty...

      By the time you're done planting, watering, growing, harvesting, storing, and refining this stuff into ethanol (and then burning the ethanol), have you put more back into the atmos then you took out?

  • Of course in the process of producing ethanol for consumption in a car, the raw amount of energy delivered to the car per gallon of ethanol will be less than the raw total amount of energy that went into producing the ethanol. It's a basic fact that no process is perfectly conservative of energy, or else we could build perpetual motion mechanisms.

    It's probably not much less efficient than oil - and more importantly corn can be renewed at a *very* fast pace compared to oil. It can also be grown where we choose, instead of explored for and drilled from special reserves. It also burns cleaner - and the extra plants should help the environment.
    • The point isn't that the fossil fuel energy is being converted directly to ethanol, but that the fuel being used doesn't dwarf the energy stored by the processed plants. If spending a unit of petrol will allow us to convert biologically stored solar energy into six units of alcohol as fuel, it's a win.

  • Coal to produce? (Score:3, Insightful)

    by Ioldanach ( 88584 ) on Wednesday August 07, 2002 @09:07AM (#4024757)
    Reading through the report, I see that in every phase of production a different fuel is accounted for. Overall, the production uses Diesel, LPG, Coal, etc... My question is, why not use corn products in this capacity? At the very least, the mills producing the ethanol and byproducts such as corn oil have an already existing source of energy already on hand. Corn oil is very similar to diesel fuel, and can be burned in a modified diesel engine. Ethanol, naturally, is a fuel in its own right or we wouldn't be talking about it. Couldn't the mills reduce their own fuel costs by using the freshly generated corn fuels to power themselves? Also, sell them back to the farmer producing the corn at a preferential rate. After all, if you're producing millions of gallons of the stuff, surely it would be more efficient to put some in a holding tank and cycle it back in than to sell it, have it trucked around, and have some coal trucked back for your furnace. All that trucking is part of what increases the embodied energy, and reduces its own energy value.
    • Probably because "clean" fuels are so in demand by environmentalists that there is a much greater novelty profit in selling a gallon of corn ethanol than in selling an equivalent amount of fossil fuel.

      Thus if ethanol becomes used on a widespread basis they probably would do so.
    • Doesn't this violate the 2nd law somehow? It gives more energy than it takes to create, so once you "prime the pump" you have limitless energy...
  • Okay, it's positive but it still isn't nearly good enough, considering it costs money and does hurt the envoirnment in other ways.

    What we need to do is eliminate our dependence on fossil fuels, regardless of cost. The corn subsides would be better spent on R&D for new technologies like fuel cells, solar energy, and fusion. This must become the new space program because humanity faces an enemy that will kill us all.

    • When are you people going to realise that there is no dependence on fossil fuels? The only reason we use LPG, petrol/gasoline and diesel oil from fossil fuels is becuase ethanol and canola are 1.5 times the price. If fossil fuels run low we use timber, ethanol and corn/canola oils and everythin continues as normal. If you took out fuel taxes people's costs would actually fall.
  • I mentioned this in the article on shipping CM corn out of the US, but it is important to note that the production of corn in the US is highly artificial, and the press release from the USDA does not provide enough information to verify that the overall equation is reasonable. If the efficiency of the farms is high enough to produce ethanol only because of other subsidies (specificly for cattle feed), it doesn't suggest that the net equation (Is the use of corn based ethanol a truely renewable fuel) is really positive Also, it ignores the other issues relating to our other problematic uses of corn which enable the mass production of corn efficiently. See the discussion that was hosted on US GM production on The Connection [theconnection.org] recently for a full discussion. The same program also discussed the corn production problems during a discussion of fast food beef production. Also, NPR reported [npr.org] on 'All Things Considered' that ethanol has negitive enviromental impacts (by releasing volital organic compounds) during processing. Also, note this bill [npr.org]. From my perspective this is probobly more a Bush/Republican PR push to demonstrate both their 'environmental friendly' policies and garner farm state votes.
  • Three big reasons that I support ethanol:

    3) It's good for the environment
    2) It supports Iowa's currently not-so-hot economy
    2b) This means that my tuition at the University of Iowa doesn't go up as fast
    But the number one reason that I support ethanol is:

    It's 5-6 cents cheaper per gallon at the pump!
    • > It's 5-6 cents cheaper per gallon at the pump!

      Unfortunatly the only state I've seen it cheaper in is Iowa. I currently attend school in Illinois where Ethanol costs more than regular unleaded gasoline. I'd also be willing to bet, that this price decline in Iowa is government funded and thus is helping up your tuition even faster:).
    • That's due to sigfuckingnificant subsidies. All things being equal, and in places where state's don't subsidize its use, ethanol is more expensive per gallon.

      The shitty fucking truck stop here sells E85, 85% ethanol, 15% gasoline mix. That costs about 60-80% more per gallon than gasoline. Factor in the fact that ethanol just doesn't have the same fuel value, and it doesn't look so good. Plus, it takes some fancy fucking engine that few auto makers produce to burn.

      It doesn't support the community for shit. For every 5 cent per gallon loss, that's five cents that doesn't go to the state department of transportation, meaning that the funding for replacing shitty fucking roads has to come from somewhere else -- either more taxes on normal gasoline, or higher vehicle licensing fees.

      Don't kid yourself. Education isn't funded by ethanol. It's merely a way to placate angry farmers who reward politicans with votes. That's the real benefit. Keeping the trough full for farmers, and keeping incumbents in office.

  • Well, to be more precise the intensity and methods of modern farming is a sword of Damocles above us all. Even if we ignore the erosion of the top soil, the depletion of water levels is set to bring about famine of a scale never before seen. The midwest's Ogallala aquifer is being drained at unsustainable rates, and things are even worse in Arizona and Texas [216.239.53.100]. America isn't alone in this; the whole world [findarticles.com]is poised to lose it's fresh water resources.

    I'm not saying that oil is GOOD, only that Ethanol is not the panacea many make it out to be, and it carries problems as severe as oil. The world needs a much different energy source, but that is a whole 'nother topic.

  • ...such that every BTU of existing liquid (fossil) fuels spent produces a 6 BTU return.

    I don't think so. The article stated that there was a net gain of ~21,000 BTUs per gallon and that a gallon of gas contains ~125,000 BTUs. Assuming that ethanol and gasoline have the same number of BTUs/gallon, then you get 6 BTUs of output for every 5 BTUs of input.

    Given all of the other problems with corn/ethanol, a 20% return looks pretty dubious.

    Johnny

  • It has been argued that using corn-derived ethanol as a fuel costs more in energy than what is produced.

    Can someone point me to a fuel source that doesn't follow this formula?

    It took more energy to produce oil then what is produced, but since the production happened millions of years ago, we don't really think about the energy that went into the production
    (And then you need to expend the energy to convert the oil into a usable fuel source like gasoline or diesel).

    If you had a fuel source that cost LESS energy to create then to produce, couldn't you harness the surplus, and use that to produce more fuel, etc, etc.... thereby creating an endless energy source?

    Or am I misunderstanding things (Haven't had my coffee yet, but we all know that it takes more energy to produce coffee then the energy I derive from the 'fuel source').
    • When they say it costs more in energy than what is produced, they're not taking into account the energy that the suns rays provide when growing the corn. They're just talking about the energy that we already have, in usable form, that we use to create ethanol. Energy from the sun isn't taken into account because we didn't have that energy to begin with, but only got it by growing the corn.
    • Amplifying the other response, since ethanol is being promoted as a solution to environmental problems, it hardly makes sense environmentally to spend 1.2x non-earth-safe joules to get 1 so-called-"earth-safe" joule. You end up with a net loss to the environment.

      However, not to be excessively flamebait-y, this kind of math is rather typical of many (not all) environmentalists, who seem to care about process more then results. This leaves someone like me, who cares about results, somewhat out in the cold, as I can't stomach calling myself an environmentalist, even though I would like to be one.

    • There is more than 1 source of energy:

      • Solar via plants
      • Fuel for processing and vehicles
      • Manufacturing
      • etc

      When looking at a possible "energy source" we only look at the energy we use up - ie. fuel, not that which we get for free - ie. solar. The claim is that the fuel used has more energy than the ethanol produced - which can still be economically viable due to subsidies.

      This report is very good news (if it is true) because it means that if ethanol and other corn derivatives can fuel their own extraction process (quite possible), then lots of ethanol is produced from a self-sustaining farm.

      The energy "produced" comes originally from the sun, as do all forms of energy used by man, apart from geothermal and probably nuclear.

      A an aside, shoal oil (I believe) is an example of a fuel which requires more energy to get out of the ground than it produces. In Canada "stranded gas" (no pipeline) is used to extract the oil (which is easier to transport). Take this with a grain of salt, as I don't have references with me.

      • ...which can still be economically viable due to subsidies.

        If it has to be subsidized, it's only "viable" for the farmer being subsidized. For the economy as a whole, it's a net drag.

        Living in Alaska in a house with no insulation is a "viable" option if my heating bill is subsidized enough. Does that make it a good idea? Didn't think so...
  • I recently talked to a friend who was explained to me a new process that could produce ethanol out of hay. The process could be used on any type of hay and furthurmore because of farming practices (at least in Alberta) there is plenty of extra hay that just ends up being burned or otherwise disposed of since we don't till the soil can't reclaim it all. They know how to build the plant and have found they can use about 20% ethanol in existing engines with no noticable side effects and it reduces emmissions by about 2/3s.
    Now if only our pro-oil, anti-Kyoto, alcoholic, high school drop-out premier would actually get behind proposals like this and actually start diversifying our economy...

    • Re:Hay (Score:1, Interesting)

      by Anonymous Coward
      Interesting, since the major oil companies have invested in Ethanol research and most declaired it worthless. While it is an alternative there is little, or no net benefit to using it.

      swapping one for the other without a netgain in an environment like ours is actually a net lose as there is pre-existing infrastructure to deal with. New markets, moving towards industrialization could take advantage of it but for the rest of us it doesn't make sense.

  • I don't believe it (Score:3, Insightful)

    by Rick the Red ( 307103 ) <Rick.The.Red@gm[ ].com ['ail' in gap]> on Wednesday August 07, 2002 @01:29PM (#4026561) Journal
    Personally, I trust last year's Cornell study -- which showed that ethanol production is an energy loss -- over this new USDA study. Why? Because Cornell is a neutral party, with nothing to gain either way, while the USDA is beholden to both the President (who wants a cheap fix for those pesky enviornmental rules, and ethanol offers his oil buddies just such a cheap fix) and the farmers, who absolutely love a new market for their crops. This is the fox talking, folks! When do we hear the hen's side of the story?

    This is the same USDA that says we don't need labels on genetically modified food, too! Oh, yeah, I trust this study -- as far as I can flush it.

  • When we eventually get fusion power that accomplishes what we truely need (Inexaustable, clean, power supply), Eth becomes a viable source.

    The barrier (its energy efficiency) becomes a mass production issue that would result in massive Eth plants being closely related to the Fusion power industry.

    Fusion is a serious technology that humanity needs to achieve.

    Unlimited power could prevent an ice-age from having any impact. You could do away with fossil fuels and natural gas in house heating.

    You could build massive mag cannons to shoot stuff into space.

    Do not rule an Eth car out once Fusion is realized. Electric cars may be too 'battery' heavy but hybrid non-fossil based cars will definately appear.

    -Tim
  • Don't drink and drive!

  • net gain in energy such that every BTU of existing liquid (fossil) fuels spent produces a 6 BTU return.

    What I want to see is the figures showing that you can grow the crops, harvest them, turn them into ethanol and transport them, using ethanol rather than fossil fuels and still get a return. Theoretically it is possible because of all the solar energy being input into the equation, but at best the studies I've seen today are conflicting on this issue.

  • Just FYI... (Score:2, Interesting)

    by Anonymous Coward
    Here in Brazil, ethanol is a government-sponsored alternative to lessen our air pollution problems and economic dependency on imported oil.

    It is sold in nearly every gas station (at least in the major cities) for 65% of the gas price, maximum. In the 70's-80's it was such a success that few wanted a gas-powered car.

    In the 90's, due to more reasonable oil prices, ethanol (also popularly known here as alcohol) fell in disgrace. Some even believed it was doomed.

    It's making a coming back, now. I'm using an old ethanol-powered car (a Ford) and considering buying a new one in the near future.

    The increased mileage is IMHO more than enough balanced by many advantages:
    a) the motor works better, accelerates more (ethanol is a better fuel);
    b) pollution is much reduced and doesn't smell bad like gasoline;
    c) there's a law that ensure that ethanol will be sold at 65% of gas price maximum (currently around 50%) -- this makes ethanol cars cheaper on a mile-by-mile basis (YMMV -- well, not really, *it is cheaper*, but I thought it would be funny here... hahahaha);
    d) gas-fuelled cars have a slightly heavier tax burden;
    e) some modern cars are built "reversible", I think, and can go both on gas and on ethanol. It seems the electronic injection can adjust to any mixture of both -- or so I've heard.

    BTW, ethanol is produced from sugar -- more exactly sugarcane -- contact us if you want to acquire the technology... :)

    I'm very surprised that corn can also be used... but then again IANAChemist.

    I could go into further detail, but the beauty is this: you go to a gas station and the serviceman there asks you: "Gas or alcohol?" and you say "Alcohol, fill it, please", with the assuring feeling that your wallet won't be emptied.

  • Corn is one source. Direct synthesis is another. (Score:3, Insightful)

    by Christopher Thomas ( 11717 ) on Wednesday August 07, 2002 @10:08PM (#4030390)
    Another option is to write off biologicals altogether and produce ethanol (or methanol, which is easier and still a good fuel) directly from CO2 and hydrogen.

    You need a power plant to supply the electricity to produce the hydrogen, so this is an energy storage scheme as opposed to an energy collection scheme, but I strongly suspect that the end-to-end system efficiency will still be greater than with corn fermentation.

    This has the advantage of letting you build the infrastructure for alternate fuel production (hydrogen or methanol, which can be processed by fuel cells and stored at far higher density than hydrogen) without having to replace every car on the road (an internal combustion engine can burn methanol).

    Cost for the methanol (or ethanol) is potentially very cheap, even with high energy costs. The efficiency of the methanol synthesis step is what will limit price (and of atmospheric CO2 extraction if you get tired of shipping in limestone).
    • Read what an earlier poster said about "improving the carbon equation."

      Instead of pumping up 50 million year old carbon that has been sequestered all this time, using ethanol helps make it more of a zero sum game. Ideally, you're growing (removing) the same amount of carbon from the atmosphere that you're burning as EtOH.

      Now you're talking about taking carbon that's trapped in rocks and releasing it into the atmosphere (when the ethanol is burned)? What a bad plan, if you believe the global warming crowd at all.
      • Now you're talking about taking carbon that's trapped in rocks and releasing it into the atmosphere (when the ethanol is burned)? What a bad plan, if you believe the global warming crowd at all.

        As per my original post, you can extract it from the atmosphere by effusion or other methods easily enough. Limestone is just likely to be cheaper. Switching to alcohol-based vehicles is a Good Thing either way, as it burns more cleanly than gasoline, can be used in fuel cells (encouraging the switchover to fuel cell technology), and sets up the alcohol synthesis infrastructure, which you'd need with either source of CO2.

        Limestone would be used until there was a good reason not to use it (like global warming becoming a big enough political concern). The infrastructure is desirable regardless.
    • Methanol may be easier to produce but it is toxic.
      But you can drink ethanol (and some people do).
      • Methanol may be easier to produce but it is toxic. But you can drink ethanol (and some people do).

        Gasoline's toxic too :).

        Methanol and ethanol smell different. Confusing them isn't a problem. Any methanol sold at the pump will probably be spiked with both an additional odour agent and some kind of illness-inducing agent like any other denatured alcohol.

        In summary, I don't see how toxicity is a concern.

        Remember, any ethanol sold at the gas pump will be denatured also.
  • It's too bad this discussion is so old. Somebody should have mentioned the uses of hemp (that's marijuana everybody!) as a source of ethanol (and biodiesel [and biodiesohol]). When presented with the economic facts of hemp, it shines a light on how horribly pathetic the state of the status quo is. But remember, "Just say no!" And stay horribly brainwashed while you're at it.

    Or if you're brave, go study the economic and scientific history of cannabis sativa (especially the economic situation surrounding its criminalization).
  • If you are interested in the mind numbing details of the chemistry of gasoline, how oxygenates such as ethanol work, etc., I suggest you check out the rec.autos.tech Gasoline FAQ [mit.edu]. It's a bit dated (96?) so some of the programs described as "future" are really current or past trends. But it's still a pretty good read if you want the low-down on what's actually in gasoline, what octane is all about, and why we have these pesky oxygenates. Here's the table of contents to whet your appetite.


    3. What Advantage will I gain from reading this FAQ?
    4. What is Gasoline?
    4.1 Where does crude oil come from?.
    4.2 When will we run out of crude oil?.
    4.3 What is the history of gasoline?
    4.4 What are the hydrocarbons in gasoline?
    4.5 What are oxygenates?
    4.6 Why were alkyl lead compounds added?
    4.7 Why not use other organometallic compounds?
    4.8 What do the refining processes do?
    4.9 What energy is released when gasoline is burned?
    4.10 What are the gasoline specifications?
    4.11 What are the effects of the specified fuel properties?
    4.12 Are brands different?
    4.13 What is a typical composition?
    4.14 Is gasoline toxic or carcinogenic?
    4.15 Is unleaded gasoline more toxic than leaded?
    4.16 Is reformulated gasoline more toxic than unleaded?
    4.17 Are all oxygenated gasolines also reformulated gasolines?
    5. Why is Gasoline Composition Changing?
    5.1 Why pick on cars and gasoline?
    5.2 Why are there seasonal changes?
    5.3 Why were alkyl lead compounds removed?
    5.4 Why are evaporative emissions a problem?
    5.5 Why control tailpipe emissions?
    5.6 Why do exhaust catalysts influence fuel composition?
    5.7 Why are "cold start" emissions so important?
    5.8 When will the emissions be "clean enough"?
    5.9 Why are only some gasoline compounds restricted?
    5.10 What does "renewable" fuel or oxygenate mean?
    5.11 Will oxygenated gasoline damage my vehicle?
    5.12 What does "reactivity" of emissions mean?
    5.13 What are "carbonyl" compounds?
    5.14 What are "gross polluters"?
    6. What do Fuel Octane ratings really indicate?
    6.1 Who invented Octane Ratings?
    6.2 Why do we need Octane Ratings?
    6.3 What fuel property does the Octane Rating measure?
    6.4 Why are two ratings used to obtain the pump rating?
    6.5 What does the Motor Octane rating measure?
    6.6 What does the Research Octane rating measure?
    6.7 Why is the difference called "sensitivity"?
    6.8 What sort of engine is used to rate fuels?
    6.9 How is the Octane rating determined?
    6.10 What is the Octane Distribution of the fuel?
    6.11 What is a "delta Research Octane number"?
    6.12 How do other fuel properties affect octane?
    6.13 Can higher octane fuels give me more power?
    6.14 Does low octane fuel increase engine wear?
    6.15 Can I mix different octane fuel grades?
    6.16 What happens if I use the wrong octane fuel?
    6.17 Can I tune the engine to use another octane fuel?
    6.18 How can I increase the fuel octane?
    6.19 Are aviation gasoline octane numbers comparable?
    6.20 Can mothballs increase octane?
    7. What parameters determine octane requirement?
    7.1 What is the Octane Number Requirement of a Vehicle?
    7.2 What is the effect of Compression ratio?
    7.3 What is the effect of changing the air-fuel ratio?
    7.4 What is the effect of changing the ignition timing
    7.5 What is the effect of engine management systems?
    7.6 What is the effect of temperature and Load?
    7.7 What is the effect of engine speed?
    7.8 What is the effect of engine deposits?
    7.9 What is the Road Octane Number of a Fuel?
    7.10 What is the effect of air temperature?.
    7.11 What is the effect of altitude?.
    7.12 What is the effect of humidity?.
    7.13 What does water injection achieve?.
    8. How can I identify and cure other fuel-related problems?
    8.1 What causes an empty fuel tank?
    8.2 Is knock the only abnormal combustion problem?
    8.3 Can I prevent carburetter icing?
    8.4 Should I store fuel to avoid the oxygenate season?
    8.5 Can I improve fuel economy by using quality gasolines?
    8.6 What is "stale" fuel, and should I use it?
    8.7 How can I remove water in the fuel tank?
    8.8 Can I use unleaded on older vehicles?
    8.9 How serious is valve seat recession on older vehicles?
    9. Alternative Fuels and Additives
    9.1 Do fuel additives work?
    9.2 Can a quality fuel help a sick engine?
    9.3 What are the advantages of alcohols and ethers?
    9.4 Why are CNG and LPG considered "cleaner" fuels.
    9.5 Why are hydrogen-powered cars not available?
    9.6 What are "fuel cells" ?
    9.7 What is a "hybrid" vehicle?
    9.8 What about other alternative fuels?
    9.9 What about alternative oxidants?
    10. Historical Legends
    10.1 The myth of Triptane
    10.2 From Honda Civic to Formula 1 Winner.
    11. References
    11.1 Books and Research Papers
    11.2 Suggested Further Reading

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