50 gallons per mile?!? That's the water cost of corn-based ethanol
The nail in the coffin of corn-based ethanol might be made of water. The magazine Environmental Science & Technology has published an article that pegs the amount of water needed to make enough corn ethanol to move a vehicle one mile at 50 gallons. That's pretty high. ES&T calculated the amount of water needed to grow the corn as well as the water that is affected by agriculture. From the article:
As biofuel production increases, a growing need exists to understand and mitigate potential impacts to water resources, primarily those associated with the agricultural stages of the biofuel life cycle (e.g., water shortages and water pollution) herein referred to as the water footprint.The worst case scenario, ES&T found, would be irrigated sorghum grown in Nebraska and turned into ethanol. This would use up to 115 gallons per mile. Corn grown there would require 50 gallons of water per mile. Say good-bye to "food vs. fuel," say hello to "Drink or drive."
The National Biodiesel Board, naturally, doesn't want to be associated with the study. The NBB issued a statement that read, in part:
As noted by the authors of the study, not all biofuels production characteristics are the same. Biodiesel is produced from recycled greases, animal fats, and vegetable oil that is a co-product of soy protein meal production. Crops are not irrigated or planted solely to produce biodiesel. Conversion of these co-products and byproducts uses very little water -- the entire U.S. biodiesel industry used less processing water in 2008 than it takes to irrigate two Sun Belt golf courses annually.
[Source: Environmental Science & Technology via Environmental Protection, National Biodiesel Board]
Reader Comments (Page 1 of 2)
AMcA 8:46PM (5/05/2009)
Coskata's cellulosic process is supposed to require only a gallon of water per gallon of ethanol produced.
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Nixon 2:14AM (5/06/2009)
Which is actually much better than the amount of water that it takes to refine oil.
This study is actually pretty silly. It does a WORST-CASE of water use, and then lets all the echo-chamber idiots repeat it as if it were the average or the norm.
But we can play this same game with gasoline too, and make it look even sillier. Producing gasoline requires water in a four major areas:
1) Refining of oil can take up to "2.5 gallons of water for every
gallon of product (Gleick, 1994)." This is mostly used when "cracking" the oil with something called steam hydro-cracking.
2) Water (steam) can be pumped into wells in order to enhance recovery.
"Gleick reports water consumption of [up to] 350 gallons of water per
gallon of oil extracted, depending upon the recovery enhancement process"
3) Drilling also has something called "Produced Water" that takes water out of aquifers. (This is not the same as the water used for recovery enhancement.)
"approximately 900 barrels of water per barrel of oil equivalent in
the Powder River Basin (Wyoming and Montana) (Rice et al., 2000)."
That's 1252.5 gallons of water per gallon of oil BEFORE you even get to number 4.
4) Ground water polution from oil drilling, leaking fuel tanks, MTBE contamination, and oil spills can polute millions of gallons of water, which would inflate this number even further (too hard for me to calculate.)
Since a barrel of oil can produce as little as half a gallon of gasoline, double the 1252.5/gallon of oil statistic to get 2505 gallons of water per gallon of gas. Stick that in a 10 mpg Ford V10 Triton F350 long-bed duelly, and you get 250 gallons of water to go one mile on a gallon of gas. (worst-case, of course. Just like the study above.)
So 250 gallons of water per gallon for gasoline, compared to 50-115 gallons of water per gallon of ethanol. This is 2-5 TIMES worse than the study came up with BEFORE even calculating the fresh water spoiled by oil polution!! See how easy it is to make statistics make something look stupid?
Snowdog 6:55AM (5/06/2009)
Great can we divert some of the multi-billions sent to the Corn lobby, into seeing if this technology is for real?? Or has someone already determined it doesn't actually look so great when everything is taken into account and that is why they can't get funding?
Nixon 9:17PM (5/06/2009)
Of course this whole argument about calculating the total impact of Corn Ethanol ignores one huge fact. The left over mash from producing Corn Ethanol is fed to cattle, and if those calories don't come from corn mash, they will have to come directly from corn.
So if you stop growing corn for Ethanol, you will have to start growing corn to replace the corn mash that is a by-product of making ethanol.
Between the two choices, which do you think consumes the most water based upon the same type of standards that this study uses:
1) Burn ethanol as fuel, and feed cattle with the corn mash. Don't burn any petroleum. No more water to refine petroleum, or hydro-crack, or forced-steam oil extraction, or produced water.
2) Burn gas as fuel, AND grow nearly the same amount of corn to replace the corn mash that is no longer a by-product of making ethanol. Nearly all the water impacts of growing the corn remains the same. Keep using water to refine oil, hydro-crack, extract, etc... All you really save is JUST the water required to actually do the distilling of the ethanol itself. But now you have to include ALL the water required for the entire oil extraction/refining/etc process.
All the sudden the math gets completely different.because the water use for the actual growing of corn, and it's associated downsteam effects mostly cancels out no matter whether you burn Ethanol as fuel, or Gasoline.
All that is left is comparing the actual amount of water used just to distill vs. the amount of water used in the entire oil lifecycle. All the sudden it becomes clear that the NET EFFECT of ethanol could very well be a LOWER amount of water being used overall.
Snowdog 10:04PM (5/06/2009)
Who says cows need corn. They can probably a lot of other plants that don't require the inputs that corn does.
jharlan 9:39PM (5/05/2009)
We have to be better than that or what's the point?
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jpm100 9:45PM (5/05/2009)
Its not exactly tap water and not all of the country has exhausted the local water supplies. In fact many people still pull it from the ground.
I guess you could report on how many trees had to die to release the carbon to make corn that was used to make ethanol too.
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kyle 10:00PM (5/05/2009)
Yeah, and we're pulling water faster than the replenishment rates from the ground. Because there's a ton of water in the ground, we haven't run out...yet. The west is always in bad shape in the summer when it comes to water. In Indiana, the ground water is predicted to be gone w/in 50 years at current rates.
Water availability is a growing concern all over the globe, and our usage rates of ground water will eventually cause a crisis. If we continue to push off and say we'll fix it later, we're gonna end up in a situation where we won't be able to fix it anymore.
I've been against corn ethanol from the start because of the water required. Corn ethanol is a waste, of water, fertilizer, good land practices, and money.
Treehugger 10:01PM (5/05/2009)
And that's not the end of the story, since the corn ethanol stuff the dead zone in the gulf of mexico is expending like crazy. Soil erosion, and using a precious non renewable resource like phosphorus to grow biofuel is just criminal.
It is time that they dicontinue this insanity of corn ethanol
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Tim 9:18AM (5/06/2009)
Yea, but it was people like YOU who forced ethanol down congressional throats along with MORE unintended consequences. Corn growers just used lobbyists to take advantage of YOUR (and the Politician’s) naiveté.
Those who champion Statist central planning over free markets have no right to complain about unintended consequences like this. Don’t like it, then let the market be free to decide what IT wants.
Politicians are NOT smarter than the market!
Hypocrite!
TX CHL Instructor 10:05PM (5/05/2009)
OMG!!! 50 gallons of water PERMANENTLY DESTROYED in the production of one gallon of ethanol!!!!
oh, wait...
Good grief, people. Ethanol is at best a mediocre fuel (and corn a really lousy feedstock), but deranged and ridiculous arguments like this are not going to sway anybody.
Every drop of water used in production of ANYTHING has already been recycled, hundreds of millions of times, and will be recycled a few hundred million more.
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Mike!!ekiM 10:13PM (5/05/2009)
Your ignoring the loss rate from your recycled water. You're even pretending there isn't any. As Kyle has pointed out, what's your replenishment rate?
TX CHL Instructor 10:47PM (5/05/2009)
What percentage of the water is permanently destroyed?
Brian P 12:34AM (5/06/2009)
None, of course. But the water may end up in a form in which, at least temporarily, it is "out of service".
Growing crops at a rate faster than what natural rainwater can supply, have to be irrigated using liquid non-saline water. In most places, that means either river water or ground water or both, and in many places in the USA, those sources are in limited supply. Certainly the water that doesn't become part of the final product isn't "destroyed", but it's largely evaporated. After it has been evaporated, it will of course come down as rain somewhere else, but not necessarily in the place or time where you need it.
It's well known that the water table in many areas of the USA has been going down, because ground water isn't filtering down through the ground to replenish it as fast as it is being pumped out of the ground.
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Captain Morgan 1:00AM (5/06/2009)
As the saying goes, "You can please some of the people some of the time, but you can't please all of the people all of the time." Whoever said that forgot, though, about those people whom you can't please ANY of the time ... I think they're called 'environmentalists'.
Enough already with the "nails in the coffin" of corn-based ethanol. Everyone knows that corn-based biofuels are not a long-term solution. They do have a place, however, as a bridge to more sustainable next-generation biofuels. Like any petroleum alternative, there is infrastructure that needs to be developed to support them. If ethanol magically started raining from the sky tomorrow, we would still need mass availability of vehicles that can use make use of it, distribution systems, etc. If there is no market for next-generation biofules, then what is the incentive to develop them? That's what today's biofuels are slowly starting to do ... create the market.
I have very little respect for authors who feel the need to criticize without offering suggestions of their own. What's your suggestion, Mr. Blanco? Should we stick with petroleum? Maybe we should all switch to those electric vehicles ... which aren't available yet? I suppose we could all start biking or walking everywhere, but then you would just complain that we're drinking too much water per mile. Well, you've certainly inspired me to go out tomorrow and fill up my flex-fuel vehicle with a heapin' helpin' of E85. Since the environment is screwed either way, I guess the farmer down the road can use my gas money more than the Saudi royal family.
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Thunderbuck 7:22PM (5/06/2009)
Hear, hear!
I find some of the objections to any of these alternate propulsion technologies (biofuels, electrics, hybrids) to be astounding at times.
The internal combustion engine has had over a century of development from thousands of companies spending hundreds of billions of dollars. OF COURSE it's a mature technology.
Any newcomer is going to need some time to mature, and no technology is going to be a precise replacement, but if we dismiss all alternatives out of hand, what are we left with?
Addison 1:58AM (5/06/2009)
Did you know that rain forests are destroyed to make room for corn fields that are used to produce ethanol? The production of the ethanol isn't just using a lot of water. The major way to clear the forests is to burn them down. Brazil has the worst record when it comes to releasing greenhouse gases. The cause? Burning down rain forests. Great, lets burn down rain forests, waste a ton of water, and top that off with the reduction of biodiversity.
And what's that? Ethanol is a "bridge" to other biofuels? We need to develop an infrastructure that supports ethanol? Screw that. Have you ever heard of electricity? There's already an infrastructure for you. Plug an electric car into the outlet in your garage at night. Electric cars are already being put into mass production. Sure it's expensive right now but prices will come down. Lower priced electric vehicles are being developed.
How about hybrid gasoline-electric vehicles? BMW and other companies are developing this type of vehicle that places an electric motor on each individual wheel. No power distribution from a single motor to four wheels needed. Each wheel has its own power.
The farmer down the road Captain Morgan? I don't think farmers down the road or across the country can supply our nation with enough corn for our cars...
Also, if you have something against the idea of saving the environment, maybe you should just go and rid the world of yourself. In case you didn't realize it, you live in a little thing called the environment that wasn't meant to just be wasted by people. If humans waste the environment, eventually the environment will waste humans by not providing what we need.
'Nuff said. Sorry if my thoughts are a little disorganized.
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Nixon 2:17AM (5/06/2009)
"Since a barrel of oil can produce as little as half a gallon of gasoline"
Should have been:
"Since a barrel of oil can produce as little as half a barrel of gasoline"
Sorry for the typo. The numbers don't change
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paulwesterberg 10:36AM (5/06/2009)
I wonder how much water is used for tar sands extraction?
Kwolek 2:52AM (5/06/2009)
Would you get your facts from college professors in ivory towers using computer modeling, fuzzy math and false assumptions? Or would you get the facts from someone who knows exactly how much water goes into making a gallon of ethanol? That would be Jeff Broin, the worlds largest producer of ethanol. (May 2009 Issue - Ethanol Producer Magazine) Broin says his company, Poet, is currently using only 3 gallons of water to make 1 gallon of ethanol. Over 70 percent of feed corn is NOT irrigated. Apply that to the average vehicle that gets 20 miles a gallon, and you go 20 miles on 3 gallons of water. That’s 0.15 gallons per mile. Apply 3 gallons of water to Douglas Pelmear’s (HP2G LLC) 110 MPGe 400 HP ethanol engine, and you get 0.027 gallons per mile. The figures that Blanco uses above are the worse case scenario from the study – not the average. The study uses 16 miles a gallon, a lowball, when we now have ethanol optimized engines by Ricardo, Suzuki, Lotus and now HP2G that get 40 to 110 MPG on ethanol.
Furthermore the referenced article ”The Water Footprint of Biofuels: A Drink or Drive Issue?” does Not mention that it takes 1,851 gallons of water to refine one barrel of petroleum into 42 gallons of gasoline. That’s 44 gallons of water per gallon of gasoline. So, the truth is – It takes a lot more water to refine a gallon of gasoline than it takes to refine a gallon of ethanol, over 10 times more. Every gallon of ethanol that replaces gasoline actually reduces water consumption many times over.
The referenced article “The Water Footprint of Biofuels: A Drink or Drive Issue?” also falls short, because it does not allocate a portion of the water usage to the co-products of corn ethanol, high protein distillers grains livestock feed and corn oil. It falsely assigns all water usage to ethanol, which is only the starch component of feed corn.
Also the study does Not mention that algae production is being integrated into corn ethanol refineries (Green Plains and GreenShift). Waste water and waste CO2 from corn ethanol refineries will be recycled to algae production. That will greatly improve the energy balance and the ecological use of water at an ethanol refinery, because you will get many more gallons of fuel and tons of feed out of the recycled water.
“The Water Footprint of Biofuels: A Drink or Drive Issue?” also creates the false impression that you get less mileage out of ethanol than you do from gasoline or diesel, because ethanol has substantially less BTUs. That used to be a valid argument, that is, until ethanol optimized engines were developed, and Douglas Pelmear showed up with his 400 HP 110 MPGe ethanol powered Mustang. The higher BTUs of gasoline and diesel are no match for ethanol’s higher octane, super fast flame speed and rapid vaporization rate, in ethanol optimized engines. Try getting 110 MPG out of a 400 HP diesel engine in a full size car.
“The Water Footprint of Biofuels: A Drink or Drive Issue?” also makes the stupid comparison of ethanol and biodiesel, which are liquid fuels carried onboard a motor vehicle, with numerous other forms of energy used for power production, such as nuclear power and steam turbines. Try running your next vehicle with a nuclear power plant or a steam turbine. This is a ridiculous comparison. What is conveniently omitted is a comparison of water usage between liquid gasoline refining and ethanol refining. Ethanol wins that one.
“The Water Footprint of Biofuels: A Drink or Drive Issue?” also creates the false impression that nitrogen and phosphorous run-off from chemical fertilizers, especially from corn and soybean crops, is the main cause of nutrient loading in the Mississippi River and the Gulf of Mexico, causing algae blumes and dead zones (eutrophication and hypoxia). There are numerous other causes. This can also be attributed to unfinished septic system effluent and municipal sewage effluent which is typically released into the watershed during heavy rains. It can also be attributed to fertilizers applied to many other agricultural crops, besides corn and soybeans. It can also be attributed to manure effluent from dairy farms, pig farms, poultry farms, livestock feedlots, etc.. Also from chemical fertilizers and pesticides being applied to lawns and gardens, and from industrial wastes discharged into the watershed. Numerous other algae blumes caused by nutrient overload are Not being caused primarily by corn or soybeans. The Chesapeake Bay algae blume, for example is caused primarily by manure run-off from chicken farms, industrial wastes and incomplete sewage treatment which runs off into the watershed.
The reference paper also ignores 700 million tons of biomass waste which can be used to produce biofuels, which should be one of their recommendations. It also ignores all the sources of waste water effluent, such as sewage disposal plants, ethanol refineries, food processing waste effluent, industrial waste effluent, agricultural waste effluent, and biogas digester waste effluent. We have a huge potential to mitigate and exploit this waste water for producing algae and duckweed as a major source of biomass feedstock for biofuels.
This position paper ends on a positive note: “However through energy conservation and careful agricultural methods and water usage planning, we can have our drive and drink our water too”. I agree. We need to rethink water conservation, but we also need biofuels. Omitting vital information and twisting the facts is not the way to do it.
This slanted article was partially funded by SHELL Center for Sustainability. That ought to tell you something.
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