Talk:Ethanol fuel/Archive 1

Neutrality
This article seems to have a negative point of view, and does not mention any possibilities, per se, about fuel-ohols, so to speak. It seems like the author is trying to discredit the posibility.

Rgenung


 * Okay. The article is much better now, and clearly presents both sides. I'm going to remove the neutrality template from the article. Robotbeat 04:16, 28 January 2006 (UTC)


 * ive added some economic facts regarding energy quality that helps balance POV Anlace


 * I disagree that the article has achieved neutrality. It does not mention the smog studies, the severity of the pollution concerns due to the industrial agricultural methods that produce the corn, the government subsidies on corn that allow ethanol producers to profit at the high cost of taxpayers, or the extremely negative effects on the fertility and quality of the land that the industrial production of corn has wrought.  I am re-attaching the neutrality template. Kitarra 03:38, 22 February 2007 (UTC)

This page doesnt seem neutral to me. Reads like a memo from the corn lobby! Even the tone is not neutral.

Interestingly, i find the above anonymous comment an attack from the oil lobby on a rapidly emerging sustainable technology. I think that the article is rather biased towards the "high price" of production, which doesn't include savings brought about by economies of scale or government subsidy.

Also, this article does not touch on the fact that higher fuel efficiencies and lower production price can be achieved by leaving part of the water in solution with the ethanol (e.g., 70% ethanol/30% water). This serves to greatly simplify production and also allows for an increase in fuel efficiency because the water contained in the fuel expands greatly when super-heated in the combustion chamber. frank5000

Frank, that's not correct. To heat the water, you must input a great deal of energy. Furthermore, current engines are not designed to have water in the system. If water worked well with ethanol, it would likely work well with gasoline, and vehicle engines would designed to make use of it. SylvanScientist

Err, one problem noted by a non-scientist - how would you get the water to dissolve in the petrol? Maybe that's why... Pete

Perhaps. I overreacted ... I read something in the article that suggested that a ethanol/water blend of 96/4% is used in Brazil due to the inability to remove the rest of the water via distillation (so more expensive methods must be found). 30% water sounds utterly unrealistic, but in the 4% case perhaps the money saved in not removing the rest of the water outweighs the non-combustion of the water in the engine. Still, the article is the only place I’ve heard of that. Incidentally, I’m no scientist either, merely an undergrad of chemical engineering. --SylvanScientist 05:29, 9 August 2006 (UTC)

Both USDA and DOE say that the energy balance is positive. This dispute has been resolved. Therefore, this page is biased against ethanol fuel. http://www.ers.usda.gov/publications/aer721/ http://www.transportation.anl.gov/research/systems_analysis/fuel_ethanol.html

I couldn't find any reference to the concern that ethanol creates more smog by releasing more hydrocarbons into the atmosphere than regular gasoline. Yet, I've seen it mentioned in several newspaper articles -- including in the NY Times. Shouldn't this be at least addressed?

Newspapers are often inaccurate and I've never heard of that concern. I'd suspect that ethanol burn more completely due to the improved amount of oxygen. Is there any evidence for greater smog production from ethanol? SylvanScientist

Well, that ethanol can produce more smog-causing (and other) pollutants than does regular gasoline has been widely reported. Here's the mention that came across on the AP Wire: http://www.msnbc.msn.com/id/13806142/page/2/. Whether its true or not, I have no idea. That's essentially why I came to read this Wikipedia entry -- to find out more details. It would be nice if some mention, explanation, or refutation were provided here. I've also seen it mentioned: http://www.planetark.org/dailynewsstory.cfm?newsid=11564 and other environmental sites.

Ah. Thank you for the links. I'm honestly not completely certain of the entire composition emissions of ethanol. However, I do know the Southwestern Research Institute (SwRI) did a study of the emissions of an engine specially configured to run on pure ethanol (see here). They found that the modified vehicle met the US standards for Ultra Low Emissions Vehicles in 2 of 3 categories. Of course, this is a case of pure ethanol, rather than a gasoline/ ethanol blend. Also, it is in a modified engine. I believe the general consensus is that in a vehicle designed to run on pure gasoline or a gasoline/ethanol mix has lower MPG than pure gasoline. This might indicate an inefficiency in burning the fuel which could lead to increased pollution, but I don’t have any evidence one way or the other on that. --SylvanScientist 17:55, 8 August 2006 (UTC) There is also an increase in vapor pressure when mixing with gasoline in concentrations above 10%, that diminishes once the concentration of ethanol exceeds 50%. Higher vapor pressure can cause an increase in evaporative emissions.

Emissions on E85 ethanol are roughly equivalent to gasoline in most respects. It's difficult to argue that it's better/worse/same for many reasons. First, what are you using for the comparison? Steady state emissions before a catalytic converter at a stoichiometric air/fuel ratio? To be honest, I don't know what the answer is for that situation, but it's almost not even relevant since that is not the scenario which has the greatest effect on tailpipe out emissions in a motor vehicle. Emissions end up being a factor of several engine operating parameters typically referred to as the calibration. Because you can't run the same calibration for E85 and gasoline, there's no easy way to do a straight comparison. A large portion of "tailpipe" emissions (after the catalytic converter) for motor vehicles is created during the cold start when the engine and catalyst are cold. There are significant differences in the amounts of wall wet and lost fuel when comparing ethanol to gasoline, and the result is typically higher CO and HC emissions during this time. The typically richer mixture also ends up resulting in lower NOx. But this is only "typical" calibration. An engine could be calibrated to run very lean on E85 (likely not good for driveability, but it could be done) and create less CO and HC, and more NOx. For a fully warm and stabilized engine and catalyst, factors such as air/fuel bias and modulation also affect catalyst efficiency and are typically different between gasoline and E85 operation. In my experience, a gasoline calibration actually causes E85 to operate worse without recalibration. But in the end, flexible fuel vehicles certify (to EPA & CARB) to the same emissions standards on gasoline and E85, and the results are typically very close to the same. I wouldn't say ethanol is cleaner or dirtier emissions-wise. As far as fuel economy, I can't believe there's any debate. The stoichiometric air/fuel ratio of E85 is approximately 10:1 whereas it's 14.6:1 for gasoline. So for an engine running at the same load (same amount of air), you have to put in more E85 to achieve stoichiometry. While it's true that ethanol has higher octane, engines do not run knock limited (also referred to as borderline limited) all of the time, so there is not always a benefit. E85 does typically show a very slight improvement in IMEP for similar load/spark conditions, but it's only on the order of 1%. In addition, ethanol has much different surface ignition properties as compared to gasoline and it more likely to pre-ignite. Protection for pre-ignition conditions can be just as limiting as knock control.ChuckRogge 02:08, 1 March 2007 (UTC)

Ethanol produces more NOx emissions, according to the US EPA. The energy balance question has not been conclusively resolved: academics still differ as to whether the energy balance is positive or negative net of all the agricultural inputs (fertiliser takes a lot of energy to produce, and then you have to factor in transportation, which is variable depending on the location of your plant).

What this article needs is not for people to act like pr*cks in the schoolground saying "this is right and this is wrong" and trying to offer the definitive piece on ethanol but to admit that there are differences and uncertainties and reflect that in the articulation of the issues.

-matt.h2o

The current statement about "ethanol made from maize" having a negative energy return is not neutral. One should say that the majority of studies show a postive energy return but there is some debate. A better reference would be to a published review article, such as the Jan 2006 UC Berkeley review article

-PigletUSA

Yes, this does indeed seem somewhat negative...all the info I'm getting for my report is sort of against my opinion.... :P

-OwlsRock411

Insetead of using ethanol since it isn't a very good alternative, there are many other options for alternative fuels, including methanol, hydrogen, solar power, and now electric cars are popping up all over the United States.

--

This article misrepresents ethanol and puts it in a bad light. For example, after reading this article, one would be lead to believe that ethanol contributes to greenhouse gases as much as petroleum fuels. However, the amount of greenhouse gas coming out of the tailpipe of the car burning the fuel is completely irrelevant. What is important is the net carbon dioxide output, which is zero because all carbon dioxide released from the burning of ethanol was removed from the air when the plants were grown and will be removed from the air to produce more fuel.

The alternatives section is probably the worst part of the article. While battery powered and compressed air powered vehicles may release no greenhouse gases directly from the car, they require energy to charge them, energy that would currently be derived from fossil fuels. Therefore all that these technologies do is move the pollution from the location of the car to the location of the power plant. Since global warming is a global problem this isn't even a benefit when considering greenhouse gas emissions.

This article seriously and inaccurately discredits ethanol as a fuel. -Tom

Two Nations
I see a split forming between the U.S. and Brazil. Do you think an article about ethanol in America should be added? For example, ethanol has been at the heart of some sociological problems in brazil, yet in the U.S. it is seen as an almost entirely benevolent development. The common theme is the sociological impact of fuel on a Nation, therefore I would also mention the adverse effect of the petroleum industry in Venezuela.


 * At the present day, there is little to no concern with Ethanol fuel in Brazil. In fact, everyone is looking forward to get cars with flexi-fuel engines (that is, engines that run with both kind of fuels mixed together). Taxi cars for example, even have the option for 3 kinds of fuels: Natural Gas, Ethanol and regular Petrol. There ar eloads of incentives for taxi drivers to adapt their cars with environment-aware fuels.


 * I think the major problem with Ethanol in Brazil was the burn of sugarcane crops, but these are now in crontrol since the adoption of a law that forbid the burns (machines ar enow being used to harvest the sugarcane). --Pinnecco 18:41, 16 December 2005 (UTC)


 * The US experience should be fleshed out too. (I was surprised to learn that California banned MTBE and will use ethanol instead. And that was only two days after I first heard of MTBE... 8-) Then there is also the Russian methanol-from-eucaliptus program (which was news to me, too).  So yes, eventually those sections should be split off as separate articles. However methinks that some of the Brazilian numbers should be retained in the general article since they are sort of an upper limit to what can be achieved today.  For instance, my rough estimate is that it takes some 300,000 m^2 of sugarcane plantation (30 city blocks) to feed one passenger car. Obviously this is not viable unless there is plenty of cheap land with good soil. The effect of venezuelan oil does not seem much relevant (and it is hardly "adverse" for the venezuelans!) Jorge Stolfi 07:46, 19 Jun 2004 (UTC)

Biofuels
This is a minor point but, it seems that the introduction implies only ethanol can be derived from biomass. As I understand it, all sorts of fuels can be derived from biomass. Though ethanol and biodiesel are apparently the most promising of these fuels regardless the ultimate source - petroleum or biomass. My understanding is that methanol is less desirable than ethanol primarily because ethanol is almost non-toxic whereas methanol is poisonous more dangerous due to invisible fires. It may also be less economical.


 * Besides this article (alcohol as a fuel), alcohol, ethanol, and methanol, there are articles bioalcohol, biofuel, biodiesel, how to make biodiesel. These should be merged and/or reorganized and/or fleshed out. Another problem with methanol is that it is cheap only if amnufactured from natural gas, but then one would be pumping carbon into the athmosphere just as with gasoline. Jorge Stolfi 07:46, 19 Jun 2004 (UTC)

Biodiesel is particularly interesting since farm equipment can use the end product and the fuel can be produced by the farmer, or at least locally.Tobyw 08:49, 28 August 2006 (UTC)

old post
The language is extremely convoluted and the sentences are mostly way too long. Many places could use rephrasing. I tried to fix some typos and do neutral and simplifying rephrasings, but didn't touch the punctuation as it may just be american or otherwise odd :) The comments also seem to cry for figures at many places. I offer no comment on the content personally.  --blades 18:02, May 8, 2004 (UTC)

bizarre examples
Are you sure that sugarcane would grow in Germany? If yes, why they obtain sugar from beetroots? If no, statement that "if Germany were to be entirely covered with sugarcane plantations, it would get only half of its present energy needs" is obviously false. It would get nothing, as no sugarcane plant would mature.

If you want this example to shed a light on the matter, recount sugarcane to beetroots, or change the country. Otherwise, it leads to confusion and somebody (e.g. radical german eco-activists with no agricultural knowledge) could think that if Germany reduced it's energy consumption by 2/3, it would rely on sugarcane as only energy source.

grzes


 * Point taken. However changing the example to beets is not good either because it would make it seem that the problem is the climate and what crops can grow (beet vs sugarcane), which is not what is in question. The real problem is land availability (Germany uses lots of energy and has no room to spare for fuel plantations, of any kind, whereas Brazil uses less energy and still has plenty of unused or badly-used land).   I will see if I can maek the point clearer... Jorge Stolfi 08:30, 27 Jun 2004 (UTC)


 * Problem is not only the land availablity, but as well just the climate. There is a major difference between one square km in Germany and one square km in Brazil, and the difference is much larger than the difference between solar exposures of these lands. Germany is not only less solarized, but also is much colder, has winter (excluded from growing) and so on. The same problem applies to most advanced (and thus energy-consuming) countries in the world. Sugarcane will grow in hardly any of them. In these countries usually beetroots may grow, but beetroot has way poorer efficiency than sugarcane (which is the most efficient of known crops). grzes


 * I don't understand the sentence where it says first that if Germany were covered in sugarcane, then it would be only half the needed energy; but then goes on to say that if the clippings, etc were used then there would be enough. However the person listed pretty much every part of the plant! What was being used before? It seems as though someone was simply trying to discredit the previous statement but left it in there. Anonymous

Are we sure ethanol is "renewable"?
Pimentel states "ethanol production from corn cannot be considered renewable energy. Its production process uses more nonrenewable fossil energy resources both in the production of the corn and in the fermentation/distillation processes than is produced as ethanol energy."

The "Renewable" paragraph in the article is unqualified in stating that ethanol is renewable. That's not neutral if there are credible people disputing it, is it?

Pimentel's article is entitled "Energy and Dollar Costs of Ethanol Production with Corn."

- He Assumes that you have to use liquid fuel to produce corn. Ask the Amish if they use any gas to produce their corn...

- About the above bullet that says "Ask the Amish" -- Well, the Amish use an incredible amount of manual labor, and people need food, which would further affect the energy balance. I remember reading somewhere that if we used horses for transportation instead of cars, 1/4 of all the land in the U.S. would need to be devoted to producing horse food. There would be a similar situation going on here; The way that the Amish produce food is so less efficient than the way that we do, that it would create a host of other problems. One thing you can say is that if all the energy came from wind power or something, than it would be renewable.


 * It's not feasible to produce corn in our modern economy without using petrochemicals. Certainly not to produce corn for fuel purposes in those amounts.  The "Amish" objection is a straw man.


 * It's not a "straw man" (BTW, I don't think that "straw man" means exactly what you meant it to mean.). All that it is saying is that since the Amish do not consume any fossil fuels, yet do produce corn, then technically ethanol can be a renewable energy source. Hydrogen is not a renewable energy source in current production, since most is produced from fossil fuels, but it is still considered "renewable." What the whole point of the Amish statement was that someone challenged that ethanol can not be considered renewable. Well, there you go. It can be. Sure, it may not be reasonable to produce it renewably, but the only renewable resources that are currently worth it are hydro power and arguably geothermal and wind (and those only became feasible lately). Solar panels generally cost more than the price of all the electricity they'll ever produce, but they are still considered "renewable." Just because "ethanol" is pretty inefficient without fossil fuels doesn't mean it's impossible to produce renewably (is that a real word?). Wood is considered by everyone to be a renewable resource. Just because wood grows better with Miracle Grow doesn't make it somehow non-renewable as a whole concept. Feasibility does not determine renewability! Robotbeat 03:41, 28 January 2006 (UTC)


 * Ehanol can be considered renewable if in the production of it, some ethanol is used as energy source, something other than pertrochemicals as fertilizers. This is because plants consume CO2 from the air, thus completing a cycle.


 * This dispute whether ethanol qualifies for renewable fuel is only for the corn-based ethanol. Brazilian sugarcane-based ethanol has much better positive net energy, and comfortably fits the definition of renewable. Lifetime 04:19, 31 March 2006 (UTC)

Pimentel does not seem to represent the consensus on the energy balance - current studies and sources put the energy balance number at 1.3-1.7.Edps 02:39, 15 May 2006 (UTC)


 * Not all Ethanol is produced from corn. Secondly, I highly doubt that more in fossil fuel is used to make ethanol in any currently used method than is produced in ethanol fuel.  If that were the case, they wouldn't use it.  Current methods of obtaining ethanol from corn are not entirely renewable, but ethanol can be made in renewable methods, just not yet in quantities we want at a reasonable price. MikeNM 22:14, 14 June 2006 (UTC)

Let us not forget that the production of ethanol produces carbon dioxide and the transportation of biomass to convert into bioethanol also emits greenhouse gases, not to mention the final transportation of the ethanol to a service station for the public to use. The idea that ethanol is 'renewable' is false - despite the claim that the bioethanol crop accounts for the production of carbon dioxide. Also, if the world continues to increase in population, will there be enough agricultural space to grow crops to use as biomass? It is more renewable than fossil fuels naturally, but as oil declines, we need to transfer to a more sustainable energy resource, ideally not ethanol or bioethanol.

Pimentel's findings based on flawed data
Pimentel's study was made in 1991 and used old or inaccurate data which biased the results against ethanol. Consider that any such study requires assumtions about such things as corn yields, ethanol production technologies, and fertilizers. Others including the USDA have come to a different conclusion than Pimentel's. See "Estimating the Net Energy Balance of Corn Ethanol" by Hosein Shapouri, James A. Duffield and Michael S. Graboski, which discredits Pimentel's study.


 * Excuse me, but I think you greatly overstate the USDA study. First of all, the issue is not really one of faulty data, it is more of system boundaries.  Pimentel (generally) uses a larger boundary than others, meaning he takes into account a more complete picture of the energy requires to produce ethanol.  For example, if one study says that the energy to grow the corn is equal to the fuel + fertilizer used, and another says that you should also take into account the energy cost of the tractor,  and other farm equipment, as well as the energy used to provide irrigation, transport the corn to the processing facility and the energy to power the people in the field (i.e. caloric value of the food eaten), which is better estimate?  Finally, it should be noted that there is a new study by Pimentel that reiterates his general finding, (Pimentel & Patzek. "Ethanol Production Using Corn, Switchgrass, and Wood; Biodiesel Production Using Soybean and Sunflower" Natural Resources Research, Vol. 14, No. 1, March 2005) that 'ethanol production using corn grain required 29% more fossil energy than the ethanol fuel produced.'  In conclusion, think about the numbers you are quibbling over, an EROI (Energy Return on Investment) of .7-.8:1 according to Pimentel, and an EROI of 1.3 according to the USDA study.  The EROI for oil extraction in the US today is around 15-20:1 for comparison (Cleveland "Net Energy for the Extraction of Oil and Gas in the US"). bobbypowers 1/31/2006


 * Pimentel is widely criticized for including whatever the energy cost, even remotely related ones, to the total calculation, intentionally skewing his result. His observation is not really an academic consensus and it is dangerous to rely on his result.  It would be better to put more widely accepted result into the article, such as ethanol production produces mild 30% net energy profit, and then note his result as a second opinion.


 * In order to understand cheese monkey slutting the criticism to Pimentel, you can read the above mentioned article "Ethanol Production....". In Table 1, he includes all the related energy for corn production. The first one is labor.  He assumes that a person uses 8000 liter of oil annually (sounds like a little stretch as US oil consumption per person is 4000 liter, but we also use coal, natural gas...), and included it to the cost of ethanol production.  But the person would use the oil anyway even if he is not involved in the production of corn to be converted to ethanol.  Is it fair to add such personal consumption of oil to the ethanol production?  He also includes gasoline, and its source is just "estimated".  Does it refer to the gas used to drive to the farm?  If so, isn't that the same energy already included in the "labor"?


 * In the calculation of the ethanol conversion, Pimentel takes the industrial average amount of steam used for ethanol production from [Illinois Corn]. Although using the same data, Pimentel comes up with 30% negative energy profit, while Illinois Corn comes up with 30% positive energy profit.  The largest source of difference comes from the fact that Illinois Corn includes the energy in the by-product from the ethanol production, while Pimentel does not.  Such by-product is usually the protein-rich remain of corn that can be fed to domestic animals.  It contains 30% of energy of the produced ethanol.  So Pimentel's study includes everything that takes to produce ethanol, but it does not include everything that comes out of it.


 * Of course, the current ethanol production uses a large amount of steam, which is generated by burning natural gas. This is not the most advanced distillation method. According to Illinois Corn, the state-of-the-art production creates 121% energy profit.  Furthermore, using a heat pump or mechanical vapor recompression [MVR] can drastically reduce the energy consumption for distillation and drying waste wet by-product. In MVR, steam can be generated with 1/10 of energy required from conventional energy source. Suntory, a large Japanese brewery, uses MVR (they call VRC) in distillation. [Suntory VRC]


 * Pimentel's study uses numbers from today's ethanol industry, which was built under the assumptions of cheap natural gas cost, but this is not the limit of ethanol production efficiency. Such advanced technology like MVP can improve the energy profit of future ethanol production. Lifetime 23:31, 25 February 2006 (UTC)

I just searched and read the Cleveland citation above and I do not find the 15-20:1 numbers. 71.248.236.173 04:45, 4 February 2006 (UTC)JAMcL3


 * I apologize, the version of that paper available on Cleveland's website is different than the one published in the peer-reviewed journal Energy (which I had read). A quote from the discussion section of that version says "The EROI for oil extraction and discovery in the 1930s was at least 100:1, and perhaps much higher, corresponding the peak in the discovery of large oil fields. As this analysis has showed, the EROI is now in the range of 20:1. The energy costs of converting crude oil to gasoline lowers the EROI to the range of 6 to 10:1." This version is available from [www.sciencedirect.com], or in Energy 30 (2005) 769–782.  bobbypowers 2/4/2006


 * the pimentel work is badly flawed; he seems to be reaching to assign dubious costs to ethanol production and begs the whole question of U.S. and EU agricultural subsidies. If the U.S. and EU are agreeing as a long term institutional policy to subsidize agriculture heavily (as the record shows) then most of these production costs are moot or sunk costs.  what else do we want to pay the farmers "not to grow".??  the whole calculation of human labor cost is absurd.  pimentel,s  implication is that we would not need as many people on the planet if we were not growing corn.the people exist and need exercise to thrive: what should we have them do? does pimentel want us to assign the agricultural workers to desk jobs? we certainly have enough unproductive public servants that we dont need to pay more to do those jobs. Anlace 18:11, 16 March 2006 (UTC)
 * an interesting point on that...Foreign Policy (the magazine) had an article a few months ago speculating on the effects of using the money that currently goes to farm subsidies, paying farmers to destroy their crops, to subsidize turning those crops into biofuels. It suggests that while due to various complications, it wouldn't completely rid us of a need for oil, we could reach the targets set for 2050 for weaning off foreign fuel by ~2020, an interesting article if you can find it. MikeNM 22:17, 14 June 2006 (UTC)

Energy Balance in the US
So, this section is in bad shape. First off, there are at least 4 studies that show that the EROI (energy return on energy invested, also known as the net energy ratio) is negative for corn ethanol (see p2 of this for a review of findings, and here for a recent Pimentel article). The statement "the energy used to produce and convert the ethanol was from abundant domestic sources" is either false or very misleading. Much (most?) of the energy used in creating fertilizer comes from natural gas, of which domestic production has peaked in the 70s and imports are on the rise. Aside from that, practically ALL of the energy to make fertilizer comes from fossil fuels, so I am not sure why the article is talking about a gain of '6.34' units of energy. This is very misleading. The EROI given for gasoline is just plain wrong (apparently whoever came up with that figure doesn't know how to do EROI analysis. It appears they are talking about the energy it takes to make gasoline from oil, and not the whole process of getting oil from the bottom of the well to your car, which I believe is up near 15:1, much better than ethanol). After I review the research in the next couple days I will try to fix the errors and misleading data (and slander of David Pimentel) contained in this section. I gladly welcome any help, or comments. bobbypowers 1/31/2006


 * i agree this section needs work, but not necessarily all in the direction implied above. one needs to state in a balanced way the results of various authors and the suitability of the assumptions of the analyses.  in general, there is a lack of analysis of energy quality and a total denial of the reality of US and EU agricultural subsidy policies in this section...see also my remarks on pimentel above one section in talk. Anlace 18:16, 16 March 2006 (UTC)

It would also seem that the claim that ethanol is 81% more energy efficient to produce than gasoline is nonesense. I think they are taking the 25% net figure for ethanol and assigning a 1.24 factor (rather that a .20 factor) but use the .80 factor for gasoline which is really (I think) just that 20% of the energy content is used in distilling. If gasoline really only netted only 80% of the energy that went into producing it, we wouldn't be using it as a primary fuel. (rwt)
 * the 80% number is this: with every unit of oil energy that is in the ground you have 0.8 left by the time you get it to the pump. Losses go to transportation and distilling.  Edps 02:50, 15 May 2006 (UTC)


 * I think it is worth mentioning that the process yielding ethanol from corn also yields other useful products. This makes, up to a certain quantity, the production of corn-based ethanol more economical than it would otherwise be, and helps offset the poor EROI, because much of the process, once again up to a limited quantity of ethanol, would have been done even if ethanol were not produced. MikeNM 22:22, 14 June 2006 (UTC)

While I am uncertain about the methods used in EROI analysis, I can say that from an economic standpoint production of ethanol, from corn and in the USA, is borderline profitable/positive. I strongly suspect that since the energy units of EROI could be converted to a monetary value, the economics of ethanol would lend an accurate representation of its practicality (both in terms of energy and not). I've generally found that EROI analysis is misleading, either intentionally or otherwise. Also, I intentionally qualified my statement about the economics of ethanol to production via corn and in the USA. Brazil, for example, has found sugarcane to be a highly profitable and energy-practical option. However, sugarcane offers greater energy per unit mass than corn, and Brazil has greater exposure to the sun (and thus to the solar energy which provides energy to plants) due to its proximity to the equator. I apologize for a lack of citations in what I've said. I'm stating this from memory because I've been doing research on the practicality of ethanol in Jamaica for months now. If anyone would like for me to go back and figure out the sources for all my information, I can do so. However, it would likely take several days in order to find it all. –SylvanScientist

I just found that this source, already referenced in the article, coincides with my suggestion thta EROI analysis in unrelible and that ethanol, even when produced in the USA and from corn, is in fact both practical and profitable. –SylvanScientist

Environmental effect
Please delete this line: "With condensed agriculture, like hydroponics and greenhouses, less land is used to grow more crops"

It is flat wrong to think that these methods would ever be used for growing fuel crops. Also, while you’re at it why not mention the deforestation problem in Brazil. -jcp-


 * Well, that is not very true. Those who hold the record for highest yields often do so with conditions similar to hydroponics and such. And, an increase in global CO2 would help grow fuel crops, as well ("greenhouse" gases). Robotbeat 17:08, 6 February 2006 (UTC)

I would like to see much more information on this. I have heard that to satisfy European demand for bioethanol, they are already destroying rainforests in the Far East to create farmland. I suspect that bioethanol is going to cause an environmental disaster by increasing the amount of farmland the world needs. Since it requires a lot of land to produce not much ethanol, this is a problem that would grow very fast as population and living standards both grow. I suspect that for this reason alone, bioethanol is unambiguously bad for the environment. Man with two legs 13:23, 21 March 2006 (UTC)

I want to know what they are doing to build and maintain the soils in which the biomass to be converted to ethanol is to be grown. It seems to me that every time you grow a crop, matter is taken from both the soil and the air to form the plant material. This implies that matter is being removed from the soil with each crop, and thus that the land will quickly lose it's fertility. They taught us in kindergarten that the "pilgrims" were taught by the "indians" to put a fish in the hole when they planted corn. Without that, corn will take too much from the soil, and it won't produce as much or as nutritious of corn the next season. It seems like chemical fertilizers will use energy to produce... and are not going to put enough matter back into the soil, relative to organic fertilizer, such as composted biomass (the stalks of that sugar cane, plus what, yard clippings?) I think that people need to just finally accept that sometimes there just isn't any more. There is no magical cornucopia that turns credit card swipes into fuel for joy rides. KarlHeg

* http://environment.about.com/od/pollution/a/sugar.htm * http://www.tierramerica.net/english/2003/0825/iacentos2.shtml * http://www.energyjustice.net/ethanol/factsheet.html "Meeting the lifetime fuel requirements of just one year's worth of U.S. population growth with   straight ethanol (assuming each baby lived 70 years), would cost 52,000 tons of insecticides,    735,000 tons of herbicides, 93 million tons of fertilizer, and the loss of 2 inches of soil    from the 12.3 billion acres on which the corn was grown.13 The U.S. only has 2.263 billion    acres of land and soil depletion is already a critical issue. Soil is being lost from corn    plantations about 12 times faster than it is being rebuilt." * The Currents of Space ?

Real Price Ethanol vs Gasoline (and Diesel)
What does "Real Price" mean? The "fundamental principal of accounting" that says that everything has a dollar value and that accounting is to be done with dollar amounts is fatally flawed. Inherent within it is a great deal of Information loss. It's like how you cannot translate from English to Chinese and then back again to get the identical thing back; one person writes the english, another who is not near the first translates, and then a third separate party translates back. Or, it's like JPEG compression... the translation from real commodity to dollars does not produce a bijective morphism.

The section regarding the price of Ethanol and Gasoline: http://en.wikipedia.org/wiki/Alcohol_fuel#Economics_of_Corn_Ethanol_in_the_U.S.

One citation hardly supports the argument that the real cost of gas at the pump should be $5-15 although it claims to have that conclusion. It refers to another article on the same website (progress.org) that actually is refering to the cost driving, not gasoline itself (such as roads and health). Furthermore, this article never mentions $15/gal for gasoline. It was only by googling International Centre for Technology Assessment that I found their website and searched their website for "gasoline" and found a PDF http://www.icta.org/doc/Real%20Price%20of%20Gasoline.pdf which is the study cited. Again they argue that projects such as government spending on highway building and military operations such as guarding oil, buying for the US petroleum reserver, and the budget of the US Coast Guard (since they fall under the Dept of Transportation and not DoD nor DoN). The Army Corps of Engineers is also considered a subsidy that lowers the cost of gasoline.

The valid points they do make are regarding tax breaks and R&D. However, they do not consider that consumers are likely paying for this from the taxes on gasoline. While gas taxes would not likely cover all of this, saying the price for gas at the pump should be $15 is quite an exageration, as is their lower range of $5.

The other link I was unable to reach from my Interne Service.

Most importantly, these articles state the consumer's possible cost, not the cost of production. The wiki entry for ethanol was only claiming the cost of ethanol production, not the cost to consumer. However, given price of oil now, ethanol is probably cheaper than gasoline (at least in California).

As refinery capacity grows and shrinks, which appears to be a huge factor, ethanol's price against gasoline will also change. However, with the increasing demand from China ethanol is likely to become cheaper than gas. There is much of the developing world that will one day want to drive cars. If this day happens when we are not ready, ethanol will extremely likely to be cheaper than petroleum fuels.

Someone should just throw ethanol out in the market and see how it does. We've probably wasted more fuel arguing about this than if we just tried using ethanol in the beginning.


 * In MN, all gasoline sold must be mixed with 10% ethanol. Also, many gas stations in MN have an 85% ethanol (15% gasoline) pump for FFV (Flexible Fuel Vehicles), which are common among newer vehicles. It turns out for us that the 85% ethanol mix costs the same (miles per dollar) as the 90% gasoline mix, since although E85 (as the ethanol mix is called) costs less per gallon, it has less energy density than gasoline. In fact, the price per mile when I last calculated it was virtually identical for the two (E85 has less taxes, which is partly why it is able to be competitive.). Robotbeat 03:48, 28 January 2006 (UTC)

Ethanol more efficient?
I read this sentence and was puzzled: "Automobiles optimized to run on ethanol can travel further per unit volume of fuel than equivalent cars setup for gasoline." This seems to go against all the empirical data: Every flexible fuel vehicle I've seen gets a lower MPG from ethanol than from gasoline. Are we saying that these vehicles are not "optimized to run on ethanol"? I thought it was a matter of simple chemistry: Ethanol has a lower energy density, therefore it takes more ethanol to move a car a mile. This could use a cite. Rhobite 20:17, 19 September 2005 (UTC)


 * No responses in weeks... I removed the paragraph since I believe it's false - every FFV gets lower mileage with E85 than with gas. Rhobite 17:10, 11 October 2005 (UTC)


 * Since there is no citation given for the claim, I think it's correct to remove it. However, your reasoning is flawed. The removed claim essentially stated that an engine optimized for ethanol could get more energy per unit volume of fuel than an engine optimized for gasoline. You claim that that's wrong because a flexible fuel engine, which can burn both ethanol and gasoline but isn't necessarily optimized to burn either, gets more energy from gas than a gas/ethanol mix. Do you see the problem? --Flatline 18:31, 11 October 2005 (UTC)


 * I thought about that, but it still contradicts what I've read (along with common sense). Ethanol has a lower energy density than gasoline, and you can't violate the laws of physics. Granted, gasoline engines are about 35% efficient. An ethanol engine which was significantly more efficient than a gasoline engine could theoretically get the same or higher mileage. But this just seems very unlikely. And I'm not aware of any ethanol-only vehicles which actually get great mileage. All modern ethanol vehicles are FFV and I don't think the old Brazilian ethanol vehicles were too efficient. Rhobite 22:54, 11 October 2005 (UTC)


 * Take a look at this site where they give the results of testing with a 1970 chevy truck burning alcohol. Their results do show improved fuel efficiency after adjusting the carb main jet size. They go on to explain that this is because of alcohol's higher octane rating which allows for higher compression ratios. I don't know enough about this stuff to judge how trustworthy they're being, but maybe you do. --Flatline 14:31, 12 October 2005 (UTC)


 * Just for reference, I found the above site by googling for "alcohol burning engine" and it was the first site listed. --Flatline 14:46, 12 October 2005 (UTC)


 * Okay, I think I see what's going on here. A gas engine may have an average efficiency of 35%, but under load it is much worse than that since the engine must be running above the fuel-optimal rpm to produce the required torque to pull the load. Burning alcohol, with it's improved torque curve, the engine does not need to be pushed as far past the fuel-optimal, and so can out-perform the gas engine for fuel efficiency while under load. It's not really a question of which fuel allows for most efficiency, but rather which deviates the least from the fuel-optimal conditions. Assuming my understanding is correct, this supports the original claim when the engine is under severe load.


 * The website I mentioned above doesn't do a comparison of an unloaded truck, but it's interesting to note that they were able to get the fuel-efficiency of the loaded truck burning alcohol to almost match the fuel-efficiency of the unloaded truck burning gas. I've found several other sites talking about using alcohol as a fuel, and they all seem to agree that in general, alcohol generates less work per unit volume than gasoline. The original claim is probably true under certain, non-optimal, conditions, but in general I would suspect that it's not true. --Flatline 16:27, 17 October 2005 (UTC)


 * The efficiency of an engine running on ethanol can be improved by raising its compression ratio from say 8 or 10:1 up to 12:1. This puts efficiency up to the same level as petrol, with 25-50% more power. A bit more tinkering can get up to 50% better mileage on the same power output (in theory.) Thomas 17:25 15 December 2005 (UTC)


 * The epa paper below talks about experimenting with a 19.5:1 compression ratio and getting greatly improved fuel efficiency over gasoline (Thanks, Ryan, for the link). Since the paper was written by the EPA's National Vehicle and Fuel Emissions Laboratory, I'm very willing to call it credible. Now that we've got a credible reference for the claim, I think we can go ahead and reintroduce into the article the claim that a modern engine designed for alcohol can, indeed, get better fuel efficiency (by volume even) than a modern engine designed for gasoline. --Flatline 21:10, 19 December 2005 (UTC)


 * I resently found a document that described modifying a Volkswagen diesel engine to burn alcohol (No diesel required for ignition) resulting in about a 40% efficiency. The document is located at http://www.epa.gov/otaq/presentations/epa-fev-isaf-no55.pdf. --Ryan 17:15, 19 December 2005 (UTC)


 * FYI: a flex fuel vehicle in Brazil does 13 Km/l with 80% gas and 9 Km/l with 96% ethanol. AFAICT, things were no different with gas-only engines versus ethanol-only engines. However, when comparing gas engines and ethanol engines, the latter had more power than the former, say, +5HP (this is not true for flexible fuel vehicles, in which the difference lowers to 2HP or less). It's generally agreed here that ethanol is a better deal than gas if it's price is at most 65% of the gasoline. This has been always true in normal circumstances, up to now. Nowadays, gas costs R$ 2,35/l (US$ 3,77/gal) and alcohol costs R$ 1,40/l (US$ 2,25/gal). Alcohol prices should be rising faster than gas prices. That's it. Note that the point of using ethanol is only to mantain a positive energy balance (an impossible thing with gasoline, as long as we can't make oil) and to keep things clean. Production should rise and reach massive adoption so that prices keep low. --Hdante 05:40, 21 December 2005 (UTC)


 * More info: it's on the news today: according to recent studies, ethanol is already more expensive than gasoline in two Brazilian states (at 70% the price of gas) and in other four, plus the federal district, it's cost is on par with gas. Only in São Paulo, where alcohol is produced, prices keep at good advandage, with a ratio of 58%. --Hdante 12:05, 21 December 2005 (UTC)

Its interesting how little we know about these issues even after all this time. As early as 1906 in the US, and the 1890s in Germany and France, it was clear that gasoline engines could be modified to use ethanol for higher power and/or equivalent fuel consumption. The U.S. Geological Service and the U.S. Navy performed 2000 tests on alcohol and gasoline engines in 1907 and 1908 in Norfolk, Va. and St. Louis, Mo. They found that much higher engine compression ratios could be achieved with alcohol than with gasoline. When the compression ratios were adjusted for each fuel, fuel economy was virtually equal despite the greater B.T.U. value of gasoline. "In regard to general cleanliness, such as absence of smoke and disagreeable odors, alcohol has many advantages over gasoline or kerosene as a fuel," the report said. "The exhaust from an alcohol engine is never clouded with a black or grayish smoke." USGS continued the comparative tests and later noted that alcohol was "a more ideal fuel than gasoline" with better efficiency despite the high cost. See Bill Kovarik's Society of Automotive History paper at: www.radford.edu/~wkovarik/papers/fuel.html#science
 * Compression ratio decides the upper use temperature of a fuel - basically, when a gas is adiabatically compressed, it heats up, and if you reach too high a temperature, the fuel/air mixture will self ignite. Each fuel/air mixture has a self ignition temperature, that can be somewhat improved by free radical scavenger anti-knocking agents such as lead tetraethyl, and alcohols are more resistant to self ignition than octane is. For thermal engines, that convert heat into mechanical energy, the carnot-engine efficiency principles stand, higher upper use temperatures translating to more efficient engines, but still below the 40% efficiency mark with almost any fuel you think up, 60% of energy blowing out the exhaust pipe. If you had a thermal engine that could operate between 3000°C and room temperature, that'd be great, but most engines are limited to between 600-1200°C and room temperature operation. Instead of converting chemical energy into heat energy with 100% effcy, then the heat energy into mechanical energy with 40% effcy, as it's done in internal combustion engines, there are fuel cells available these days that can directly convert chemical energy into electricity with 40% effcy, the electricity to mechanical energy with 97% effcy, and the remainder 60% of the chemical energy that converts into waste heat, you can still use it in a thermal engine such as an external combustion stirling engine, giving an overall 60-85% effcy number, instead of under 40% as it happens in an internal combustion engine. Of course, a fuel cell/stirling engine setup is a lot more expensive than a simple internal combustion engine, but so is a hybrid gasoline-electric car more expensive, but they are still made, becaue miles per gallon matter. But even power plants that could afford to, don't use fuel cell technology yet, let alone cars on the road. Power plants that burn coal, gas and nuclear fuels are all limited to 40% conversion efficiency, and 60% of the available energy vents out the smoke stack and cooling towers, heating the outside world instead of doing useful work. Sillybilly 04:04, 28 December 2005 (UTC)

The problem here is everyone is using flex-fuel vehicles to make the comparison. In order to run without knocking, a gasoline engine need s a fairly low compression engine. Ethanol will run in both a low compression and high compression engine. So, in order to make engines work with both fuels, the auto industry has used low compression engines. This seriously discounts the potential of ethanol as a fuel because it is being run under conditions far from peak efficiency. There is no way to switch from low to high compression on the fly (it requires a rebuild of the engine). The only way for ethanol to be taken seriously is for engines to be set up as high compression, and gasoline users can use octane boosters so that they can run it with a high compression engine. I suppose if people were comparing the price to E85 to the price of 105 octane racing fuel (which it basically is) instead of regular unleaded, there would not even be a discussion. Plus we'd be seeing 250hp from a naturally-aspirated 2.3L 4-cylinder, which provide a significant weight advantage over the 3.5L V6 needed to produce that much power with regular gas. The change need to start with the fuelling stations and the automakers reaching a deal to roll out cars and have the means to fill them up everywhere. Justin 11:20, 2/17/06


 * There is one way to switch from low compression to high compression on the fly, namely through turbocharging. By using a turbocharger (or similar compression-adjustable device) you can dynamically increase or decrease your effective compression ratio.  For example, you could use an engine with a 9.0:1 static compression ratio, determined by combustion chamber size to stroke ratio and, in addition to the engine, you have a turbocharger that is controlled by the ECU (car’s computer) to run 5-6psig of boost pressure with gasoline and maybe 18-20psig of boost with ethanol.  The higher pressure leads to a higher effective compression ratio.  It would be an excellent flex fuel solution that would afford more power and/or efficiency whether running gasoline or ethanol.  In fact, ethanol injection into the air intake of racing engines has been used for years to lower gasoline volatility and allow high boost pressures to be run.  But now you would simply be running straight ethanol.  Imagine how efficient and powerful a 1.0-1.5 liter engine would be running this type of setup with ethanol.  Harry 14:35, 02/22/2006


 * Turbocharging does not increase compression ratio, it packs more air/fuel into a fixed volume combustion chamber and increases compression pressure. It does however extract heat energy from the exhaust. Since output is regulated by a throttle, the turbo would be negated by the throttle. Cars have been developed with compression ratios which would normally be too high for the available octane rating, but the compression pressure is reduced with trick cam timing to eliminate knocking while still retaining the efficiency of higher C/R. Since an optimized unturbocharged gas/alcohol engine should always be on the verge of knocking and since output is regulated by a throttle, I can see no benefit from supercharging.  Supercharging of any type generally reduces economy in spark ignition engines, but increases it in compression ignition engines (diesels), since preignition is not a problem in that design and output is regulated by fuel delivery, not a throttle.

If US fuel consumption is replaced by alternative fuels, the reduced demand would cause a dramatic reduction in the price of oil, very likely rendering the alternative fuels uneconomical. I am not addicted to oil, it just happens to be the most economical alternative. If I could drive to the grocery store in a golf cart, I would gladly do so. Unfortunately my insurance company charges me like I am driving additional cars at the same time, so any savings would turn into an additional expense instead. Toby 10:26, 05/11/2006


 * While I don't know about the milage yield of ethanol vs. gasoline, flex-fuel vehicles are NOT optimized for ethanol, they are designed to be capable of running on E-85 (not 100% ethanol) without the engine melting, hardly meaning that they are optimized for ethanol. MikeNM 22:27, 14 June 2006 (UTC)

Southwestern Research Institute did a studythat found ethanol can get a better miles per gallon than gasoline. -SylvanScientist

Hello SylvanScientist, that study actually says that the modified 1993 Ford Taurus demonstrator running on Ed85 got 20.84 "gasoline equivalent mileage based on BTU content". This means that the actual performance was 13.75 miles per gallon of Ed85, roughly 34% less than a standard Ford Taurus running gasoline. It doesn't support the claim that ethanol can get "better" m.p.g. than gasoline. I understand from a message you sent me personally that we possibly have different views regarding ethanol efficiency. Could you state what your view is and provide some references to back it up?

Reduce Resource Curse as part of National Security
James Woolsey and Frank Gaffney advocate reduction of foreign oil use as not just a way of reducing the funding of terrorism, but necessary as to reduce the Resource curse that afflicts far more than just terrorism producing nations. There should be a broader description of their efforts, but it's also not limited to just ethanol fuel. Biodiesel, thermal depolymerization, efficiency (Woolsey drives a Prius, which is not E85 compatible), and other means are sought to this end.

Fact Check
However, studies that supposedly confirm this idea of a negative energy balance have often come under fire for using old data - whereas old distillation plants used to have negative energy balances, nowadays plants can have positive energy balances of up to 34%, whereas oil (petrol, diesel, etc.) apparently has a negative energy balance.

<--This may also be outdated. Can someone check this?-->
 * I don't know specifically about the distilation plants, but the part about oil having a negative energy balance is wrong. (I am looking to revise part of the page this weekend when I have time, I will add this then). Think about it: there are only 2 real sources of energy for people to use on this planet, solar and nuclear.  Fossil fuels can be thought of as a build up of stored energy from the sun, in a highly concentrated form (think about the amount of energy you can get if you burn a kilo of oil vs. a kilo of wood).  It currently takes one unit of energy (typically supplied by fossil fuels) to pump 15-20 units of oil and gas energy out of the ground in the US (it is much higher in the Middle East).  You then loose some energy in the conversion from oil to gasoline, but it is still probably around 12-14 units of net (positive) energy balance.  It makes sense upon reflection, how would our society have grown so 'dependent' on all of this oil and gas if it took us more energy to get it than we got from it?  bobbypowers 2/1/2006


 * Bobby, really the easiest way to find out for sure if it takes a lot more energy to make than it produces is to look at the cost of ethanol versus the cost of similar fossil fuels. If it takes, say, 2 gallons of gasoline to produce 1 gallon of ethanol, then ethanol would HAVE TO cost twice as much (at LEAST). If you include everything in the economy and the amount of gasoline it uses to produce those things, then you are going to get arbitrarily large amounts of input energy to produce ANYTHING, be it ethanol, gasoline, electricity, manufactured goods, etc. If ethanol is competitive in the market, then it is just as viable as other options. Ethanol gets a tax break in many US states because of the stimulating effect on the local economies versus imported energy. Maybe you don't believe in the market economy, but it does have a pretty good way of weeding out what works and what doesn't. Robotbeat 15:47, 6 February 2006 (UTC)


 * Robot, first of all I would like to address the issues you raise of tax breaks, which are substantial and probably the only reason corn ethanol is being produced in substantial quantities in the US right now. These tax breaks and subsidies go primarily to several large agrocomanies such as Archer Daniels Midland, and these large companies (with the aid of the USDA) have been primarily responsible for the destruction of communities and family farms across the south and midwest.  Ask just about any family farmer in America what they think of agrobusiness, and I am pretty sure you will get the same answer from all of them.  So please think of the actual people involved before you cite the stimulating effects on local economies that large subsidies to large multinational corporations would produce.  As for the market economy, I would posit that subsidies like these (and others we give to, for example, cotton growers) have the exact opposite effect that you are looking for, distorting the ability of the market to efficently allocate resources.  Second, as for finding out how much energy it takes, the idea of looking at the price of the good does not work for precicely the reasons you bring up: government subsidies and market distortions.  If we pay millions of dollars to corporations to produce ethanol, would that not make the apparent cost seem less, when really we are paying this cost with tax dollars instead of upfront at the pump?  Reasons like these are exactly the why the field of energy analysis was developed and is still relevent, it objectively answers the type of questions you are asking.  We are not including everything in the economy when we calculate the net energy of ethanol or oil, just the things relative to the production.  When you look at corn ethanol, the net energy is at most 1.67:1 (citing the most optimistic study), while if you look at US oil extraction the net energy is 15-20:1, a whole order of magnitude better.  Now, if corn ethanol clearly has advantages, less 'net' greenhouse gasses, less sulphur dioxide and NOx emissions, less VOC emissions, and it can be billed as 'sustainable' or 'renewable.'  If the net energy was really similar to that of oil, can you explain why it has not come into more widespread use in the past 30 years?  Let me know if you need further clarification as to why price analysis is seperate and not as objective (or as applicable) as energy analysis.  bobbypowers 2/14/2006


 * Bobbypowers, read the studies here (link to National Corn Growers Association)


 * One of those studies gave a 1.77 average energy-out vs energy-in ratio for dry-mill ethanol plants (1.57 average for wet-mill plants). In the state of Iowa, the state-wide average input energy per bushel of corn is 20% less than the 9-state weighted average (which gives more like a 1.85 ratio), and heat sources could be changed to burning the waste cornstalks (which would halve the necessary input power for dry mills, which gives us at least a ratio of 2 to 1). Seeing as corn yields continue to increase (in fact, the increase is accelerating since 1930) at an average rate of 1.7 bushels/acre (about 1.5% average annual rate of increase) and transportation fuel efficiencies continue to increase (better gas mileage for newer vehicles of all sorts), along with a general increase in gallons of ethanol per bushel (used to be 2.5, now 2.9 for the newer plants, and the average is currently over 2.6 gallons per bushel), it is most likely that in a decade, the energy ratio for ethanol from corn (not even including cellulosic processes which have a MUCH greater advantage as far as energy ratio) is most likely to be in the 1.8 or 2-to-1 range.


 * Now, for me to dismiss your link and it's results based on it's source would be a perfect example of the ad hominem fallacy, but I do ask you to look at the author of the website (the National Corn Grower's Association) and think about their vested interest in this subject. Looking at the comparison chart  of the net energies of the different studies, it is first off clear that there is NOT scientific consensus on the issue of the net energy of ethanol (you can not ignore three peer reviewed scientific studies which give a negative net energy when you cite non peer-reviewed studies from places like 'Agri-Foods Canada.' that give a positive net energy).  As for your optimistic future net energy ratio, it may very well be that we can keep increasing corn yields for some time, but I ask you to look at how we are doing so.  Since the green revolution there has been almost no net change in the amount of energy a corn plant gets from the sun (through the process of photosynthesis).  We have been able to achieve higher yields by redirecting where the plant invests the energy it converts from photosynthesis, specifically by concentrating it in the corn kernels.  By using things like pesticides, fungicides and incesticides the plant has to make less chemicals of its own to maintain its health.  The advent of herbicides and extensive irrigation means the plant can have a much smaller root system in order to focus more on the kernels.  All of these things I have mentioned have one thing in common: they depend on oil.  Somewhat aside from all of this, soil erosion is a severe impact of corn production.  Estimates are that about 9 tons of soil per acre are eroded per year by rain and wind in corn production areas (Lal, R. and F.J. Pierce. 1991. Soil Management for Sustainability. Ankeny, Iowa: Soil and Water Conservation Soc. in Coop. with World Assoc. of Soil and Water Conservation and Soil Sci. Soc. of Amer.).  How long do you think we can go on producing food, let alone ethanol, from land when we loose 9 tons of soil per acre per year?  10 years? 30 years?  Whatever it is, before you can bill corn ethanol as 'sustainable' and depend on being able to increase yields indefinately, I think you really need to address the issue of soil erosion and health (which right now are being maintained through the extensive use of nitrogen fertilizers, which are dependent on natural gas). bobbypowers 2/14/2006


 * I think that the most important thing for the ethanol industry is that ethanol production be as cheap as possible, since that pretty much closes the debate both factually and practically (since if it costs less for a BTU of ethanol than a BTU of a fossil fuel, it can't possibly take more fossil energy input than ethanol energy output, and also, if it's cheaper for ethanol, then businesses will be walking to the bank with money that they honestly made from ethanol and won't really care what other researchers are saying, and consumers will also just buy ethanol if it's a better deal). Robotbeat 16:44, 6 February 2006 (UTC)


 * "since if it costs less for a BTU of ethanol than a BTU of a fossil fuel, it can't possibly take more fossil energy input than ethanol energy output" I believe you contridicted this statement earlier when you mentioned the tax breaks that ethanol gets, which distort the real market costs of producing ethanol.  For a more detailed response, see my comment above. bobbypowers 2/14/2006


 * BTW, the 1.77 ratio for dry mills (1.57 ratio for wet mills) included all the energy inputs for farming, fertilization, seeding, transportation of the corn, heating (especially for fermentation), final transportation of the ethanol to the fueling stations etc. Robotbeat


 * I do not see how you can be citing the most optimistic study as the 'truth,' while at the same time chiding me for doing the opposite. The most responsible estimate to cite would be the 1.15 or 1.32 net energy ratio which is the average of all of the studies cited. bobbypowers 2/14/2006

What I don't understand is why in the studies of the critics of ethanol, they always include the energy to grow, harvest, transport, etc; but they always neglect the same for oil. Does oil still have a 12-15:1 energy balance in the US if you include the time searching for places to dig (which I've never seen studies on, but it has to be significant), building rigs (including offshore rigs), and transporting it across the world. Not to mention comparing the farm subsidies to the foreign aid we give to middle eastern countries to maintain stability of our oil supply. When ethanol gets a market of its own, the subsidies should shrink, not grow as the foreign aid has. Justin 2/17/06


 * Actually the studies on energy balance for oil take into account those sorts of things (typically accounted for under catagories such as supplies used or capital expenditures), however you do raise a good point. We are finding less and less oil, and by and large the new finds we make are smaller or harder to get fields.  Yet look at how much fossil fuels (primarily natural gas and petroleum) it takes to produce corn ethanol at 1.6:1 EROI, a tremendous amount!  This price depends not only on those farm subsidies, but on forein aid to the Middle East as well!  Even if the subsidies shrank, foreign aid would stay the same (or increase) since we would need more natural gas for the process.  Too bad everything isn't so cut and dry... bobbypowers 3/5/2006

Net Energy Section
Okay Robotbeat, so you deleted the information I added to the net energy section because it "imply[s] a lack of consensus in the ethanol producing world which doesn't exist". Frankly, that is bunk. The latest article in Science magazine (Farrel et. al, 2006) is evidence of this 'lack of consensus.' We are talking about this percisely because there is a lack of consensus (see the about discussion under Fact Check). Regardless of whether there is consensus, how would you say that information regarding how to evaluate the net energy is not applicable under the section titled 'Net Energy'? If you have problems regarding specific sentinces/statements I wrote (and I know I need to do a better job wiki-izing them), address them here or edit them, do not revert a whole section. bobbypowers 2/14/2006
 * Come to think of it, the entire next section ('Energy balance in the US') is devoted to a discussion of this lack of consensus. bobbypowers 2/14/2006
 * Well, in Minnesota, ethanol DOES have a major contribution to the fuel supply. In the last dozen years, the only studies that show a net negative energy balance for ethanol were written by Pimentel. State-of-the-art ethanol production facilities no question show a net positive energy balance. If you disagree with this, please say so. BTW, I don't want this to become too emotionally charged. I totally agree that much of the appeal for ethanol isn't its actual benefits but the "environmentally conscious" aspects of it. (Personally, this kind of environmentalism doesn't appeal to me, and I think it distracts from the conversation.) Also, ethanol production has useful high-protein byproducts, just like gasoline production has useful byproducts (i.e. motor oil, plastics, asphalt, and other things you can get from the other parts of crude oil).


 * In all, I see no reason fundamentally why corn ethanol production must have a net negative energy balance. As a physicist, I prefer to talk about the fundamental aspects of things, so while we get this whole net energy thing sorted out here on the talk page, could you first tell me whether you think that starchy corn-based ethanol fundamentally has a net negative energy balance? (Of course, back this up with sources.) Robotbeat 16:49, 14 February 2006 (UTC)


 * In theory, the way for agriculturally-based ethanol to have a net energy gain over the long term is because of "free energy" the corn is photosynthesizing from sunlight. So it certainly is theoretically possible for corn-ethanol to be a net energy gain us humans, but it's not a gaurantee.  The debate goes on, although the pro-ethanol camp is in the lead lately it seems.  I think (note opinions only from here out) that this whole article sounds like it was written by someone with a financial interest in corn ethanol production honestly.  The whole article's tone was a bit disturbingly apologetic, and seemed to blush over areas of common criticism in the way that a corn-ethanol PR-person would do.  While we're at it, I believe the argument has been successfully made in the past that our gasoline needs are higher than our potential for producing ethanol, based on available arable land that isn't already being used for food.  I could find a cite offhand, but I bet someone more interested could.


 * While I see no fundamental reason that corn ethanol must have a net negative energy balance, I feel like that question misses the larger picture. What people should be asking is how much of a positive energy balance these alternative fuels need before they can be said to be contributing to a sustainable society.  For example, even at an EROI of 1.6:1 (the best I've seen for corn-ethanol by anyones numbers), that means you are only netting .6 kcals of energy for every kcal of fossil fuel you burn.  Think about how much natural gas, coal and petroleum that is if you want to 'offset' gasoline usage any significant amount!  I totally agree about how apologetic this sounds to the corn industry.  While Pimentel may be somewhat off on his numbers, having positive net energy ratio is not the end of the story! bobbypowers 3/5/2006


 * a user with very little track record on wikipedia has conducted a major edit of ethanol fuel. i am certainly open to wording issues, since i am not associated with either petroleum or ethanol industries, and i would hope to get other experienced views on this section.  for now i am reverting the changes made by user ultiam until he can speak on this issue to justify deletions or expose his real identity of a person who has only made one prior contribution! sincerely Anlace 00:56, 19 March 2006 (UTC)


 * While it is true that I am a new member and rarely edit, I have been using wikipedia anonymously for several years. Over this time, I have gained the impression that allowing anyone to contribute is central to the spirit of the project. By extension, dismissing edits made in good faith on the basis that someone has "only made one prior contribution" seems to run contrary to this spirit. However, I may have jumped the gun in editting the section without prior discussion.  I thought it was warranted, as the current section on net energy balance reeks of POV in favor of ethanol production and is poorly written.


 * For one, the net energy balance of a fuel is a product of the energy produced from a fuel and the energy needed to produce and use it. Much of the debate over the feasibility of ethanol as a fuel involves disagreement over what is considered as part of the cost to produce a fuel. As you have suggested, indirect energy costs are sustained from fossil fuel use due to pollution and illness, and this should be mentioned.  However, it seems empty to say that the 'quality of a fuel' should be considered in net energy calculations, as 'quality' has no meaning in energy terms.  If the quality refers to the amount of energy stored in the fuel, this is already factored into the energy produced from the fuel.  If it refers to indirect costs due to pollution etc., this falls under the category of indirect energy costs.  Effects of quality that do not fit under these categories have no energy cost, and are irrelevant to a discussion of net energy.  Having said that, fossil fuels obviously have many detrimental effects (environmental damage etc.), but only those effects that have an energy cost should be considered in a section on energy balance, with the rest included elsewhere in the article.  For this reason, I removed the mention of 'energy quality', while leaving in the examples (which I thought were decent), and refocussed the section on energy balance as opposed to the effects of fossil fuels vs. ethanol.


 * In the third paragraph, I removed the mention of medical costs and soil remediation costs, as they had been covered previously. I also have trouble with the mention of gasoline production/usage having an added cost of one to ten billion dollars for two reasons: 1) there is no citation, and this number seems suspiciously low, and (2) in a section on net energy balance, monetary costs are irrelevant unless they can be related to energy costs.


 * The sentence "Even a positive but small energy balance would be problematic: if the net fuel energy balance is 50%, then, in order to eliminate the use of non-alcohol fuels, it would be necessary to produce two units of alcohol for each unit of alcohol delivered to the consumer" is very unclear. One format for reporting net energy balance should be consistently used throughout the article. In the first paragraph of the section, a net energy balance of 200% is said to result in a 2:1 ratio in EROI. Yet here, it is said that a 50% net energy balance results in a 1.5:2 EROI. Ideally, net energy balance should be explicitly mentioned in terms of the EROI. I had deleted this sentence in my edit as it seemed to detract from the article, but it seems like it could be useful if fixed up.  All other changes were to remove grammatical errors and increase readability. --Ultiam 08:47, 19 March 2006 (UTC)


 * thank you ultiam for your detailed and well reasoned response. i figured you were a more experienced contributor and just wanted you to acknowledgejthat.  i apologize for any inference that new contributors are on unequal footing.  i would be delighted to collaborate with you to improve this article.  since i didnt conribute to all of the above items you comment on, i cant or wont defend them :).  the main issues i would like to discuss with you are:


 * "indirect costs versus quality of energy". lets say we agree that there are soil remediation costs or health care costs associated with use of a particular fuel. where do you suggest we factor those in? (by the way we do need a citation for any health care costs and i agree with you they will be much higher than the value that was stateed.


 * beyond net energy balance there are real issues lurking that are not satisfactorily addressed in the article such as: what is the role of the free market in assessing viability of ethanol as a fuel? to what extent do inertial forces of marketing and historical fuel distribution control tilt the playing field?  what have we learned from the non-petroleum distribution experience of the pacific northwest?


 * i look forward to working with you and other contributors to make this an outstanding technical article, sincerely Anlace 15:31, 19 March 2006 (UTC)

For those interested in reading the peer-reviewed survey by Farrell et al. titled Ethanol Can Contribute to Energy and Environmental Goals that was published in Science not two months ago, this information is available at Berkeley Energy and Resources Group's Biofuel Analysis Meta-Model. Perhaps this source can help frame the discussion on various aspects of this article and establish consensus on some key definitions. --Robert Turner 21:24, 27 March 2006 (UTC)


 * thnks robert turner. the farrell paper shoul be required reading for anyone wanting to participate in editing the ethanol fuel article. also the other EBAMM articles help with the total perspective.  lets try to apply this and other sources and get the ethanol fuel article in better shape...what do others think? Anlace 23:07, 27 March 2006 (UTC)


 * I just added the Farrell link to the article page as well. I'm not sure if this is unnecessarily redundant or not... --Robert Turner 17:42, 28 March 2006 (UTC)

Cellulosic v. non-cellulosic ethanol
"Today the US Gas usage is approximately 360,000,000 Gallon /Day. 5.5 % of the US surface area (~ 131,400,000 Acre) would be enough to grow the biomass required to produce enough ethanol to cover the current domestic US gas demand. There are currently about 80 million acres of corn planted in the US (~40% of the world's supply of corn)."

Does this paragraph's numbers (131 Megacres) come from the standard way of producing grain alcohol from starch, or does it take into account the possibility of cheaply making ethanol from celulose? --Hal Canary 18:47, 21 February 2006 (UTC)

IIRC, the "regular" ethanol output of an acre of corn is about (140 bushels/acre, 2.5 gal/bushel =) 350gal/acre. So 350Mgal per Megacre, or about 45.5 billion gal over 131M Acres, so that would be incorrect if based on the US corn method.

The figures I've seen on cellulosic ethanol using, for example, switchgrass are that you get twice the ethanol yield per bushel, and 2-3 times the usable biomass per acre than corn. So, that results a per-acre ethanol yield of about (420 bushels/acre * 5gal/bushel=) 2,100 gal/acre. Taking that out to 131M acres would mean about 275 billion gal/year.

So I'd say it is figuring in cellulosic, though somewhere in the middle since 365*360M is only about 131B.

Now, that said here is some additional information relative to the situation. The US has, as of 2002, 363.3M acres of harvested farmland. An additional 71M is idle due to poor conditions or crop rotation. There is also about 76M acres of soybean crops grown just for animal feed. If these crops were switched to switchgrass, you could produce a bit more animal feed and a whole lotta cellulosic ethanol. Add in the unused cropland and you've now got enough land to do it with no change whatsoever to "food" crops. Ok, more than enough. That leaves plenty of room for lower yields and freaky weather.

Hope this was a decent answer, I'm new here. ;) Ucntcme 09:36, 15 March 2006 (UTC)

Currently Permitting an Ethanol Plant
I saw discussion with air issues concerning Ethanol plants. I think that is an extremely valid discussion. Having just completed an emissions inventory for a large ethanol plant, the major emissions are the following: NOx, SOx, CO, PM (particulate matter), HAPs (Hazardous Air Pollutants) (which approximate to 2 tons per year. Natural gas out of cattle is more toxic). This is normal and these emissions are emitted out of most combustable sources world wide. The major key to focus on is what emissions control technology is incorporated within the ethanol plant. Using the reductions technology along with the ethanol manufacturing process, there is an approximate 90-99% reduction of pollutants. Please, see the following links: Selective Catalytic Reduction technology (NOx reduction: http://en.wikipedia.org/wiki/Selective_catalytic_reduction) Selective Non Catalytic Reduction technology: http://www.epa.gov/eogapti1/module6/nitrogen/control/control.htm, Wet Electrostatic Precipitator technology: http://www.ppcbio.com/ppcwespworks.htm. These links will inform you of the technologies that will be applied to the process and reduce emissions. No, it won't reduce all but enough to be acceptable within state and national standards. Please see: PSD standards, http://www.epa.gov/fedrgstr/EPA-AIR/1999/September/Day-13/a23585.htm, BACT standards http://www.arb.ca.gov/bact/bact.htm (informational), and etc. We have to adhere to all of these standards prior to an ethanol plant even being permitted to construct. Our goal is to provide alternative energy choices amongst the worldwide energy consumption market. This choice is up to the consumer but, as scientists, it is our priorty to be able to at least provide a choice along with education.