Common sense says that burning a plant you regrow every year is better for the atmosphere than spewing out carbon dioxide that’s been buried underground for eons. But the truth behind biofuels and petroleum often seems to defy common sense. Neither ethanol nor gasoline bubbles out of the ground ready to put in your tank. So to figure out which one does less environmental harm, you have to calculate all the energy that goes into making it.
For years, studies have shown that ethanol is no better—or even worse—for the environment than gasoline. Some studies even claimed that it takes more energy to make a gallon of ethanol than you get from burning it.
But a new federal government-sponsored study released this week says the opposite. The report, entitled Improvements in Life Cycle Energy Efficiency and Greenhouse Gas Emissions of Corn-Ethanol, claims that a gallon of ethanol produces nearly twice as much energy as it consumes, and that switching from gasoline to ethanol cuts greenhouse gas emissions by 54 percent.
Why such different results? Better data, say the study’s authors—researchers from midwestern universities including the University of Nebraska, Iowa State, Michigan State, and the University of Wisconsin. The pessimistic studies were based on old data about crop production and inefficient early ethanol plant designs, they claim.
The making of corn is at least as important as turning it into ethanol. Up to 65 percent of all emissions come from growing and transporting the crop, for items such as tractor fuel, fertilizer and electricity. New hybrids plants produce more corn with less fertilizer.And new refineries run on efficient natural gas, recycle heat to use in other parts of the plant, and put the waste to crop good use. The scrap from the refineries actually makes nutritious cattle feed. So putting a feedlot right next to a refinery saves the emissions that would go into growing food separately and trucking it in. The best facilities save even more energy by collecting the manure and urine from cows and turning it into methane gas for use in the plant.
Unlike “clean coal” plants that exist only in the minds of their proponents, ultra-efficient ethanol operations are the norm. According to the study, the new facilities account for 60 percent of all U.S. ethanol production today and will produce 75 percent of national supply by the end of the year.
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from Kent, WA
Actually, a growing corn plant draws a lot of carbon dioxide out of the air as it grows, so the net effect of burning ethanol in your car engine should be a zero net addition of carbon. It came out of the air, it goes back into the air. Zero net gain on that score, but you still have to figure the energy cost of processing, which I would do using nuclear power. What the hell is the sense of worrying about a small local source of long-life isotopes leaking into the groundwater 10,000 years from now. If people then are not so incredibly advanced that they can handle a small, local problem like that, then they deserve to suffer. If there are no people around, then who cares?
actually corn fields dont produce nearly as much oxygen as a simple field of grass, and much so less than a forest, so if you are cutting down a field to plant corn fields, you are actually reducing the amount of Co2 that gets taken out of the air because, a corn field cannot compare to a forest, a landscape, or any other natural environment, where life thrives
Boy it's complicated figuring out the net carbon gain or loss. In a better world where most people understood that there is as yet no credible evidence that atmospheric CO2 increase causes planet-wide warming, we wouldn't be messing around with these kinds of brain-bending equations.
Regardless, biofuels are a great idea except that corn is one of the least efficient feedstocks, which is why so much attention is paid to the net energy output and carbon emissions. It's a testament to the strength of the corn lobby in the United States that we keep trying to pursue one of the least efficient ways to produce ethanol. Sugar cane and switchgrass are far more productive; algae probably (dramatically) more so. Brazil's sustainable biofuel economy runs on sugar cane ethanol.
Other very important note: Modern ethanol production and use is in its infancy. The ethanol plants will continue to improve and produce more ethanol per BTU used. The feed stocks for ethanol will continue to improve and produce more ethanol per acre and per Pound of fertalizer. The technology in ethanol burning cars will improve taking us further on a gallon of ethanol. I see so much potential for ethanol in the future if people will use it.
Has anyone ever thought about the dangers of using corn as fuel? Not only do billions of people around the world eat corn but practically all of our livestock lives on it. With farmers all changing to corn, it's creating a deficiet in other key crops and driving up the price for animal feed and corn bought at the store. Because farmers have to spend more to feed their animals; the price for meat, milk, eggs and other products that depend on these animals has sky rocketed.
Not only are we having to pay more for every day goods but many people across the world can no longer afford to buy as much as before the ethanol craze. People are starving because more corn is being deverted to make ethanol and the price of it is so high they can't afford it.
Next time you fill up your fex-fuel car with corn, just think of the cries of starving people who couldn't afford to buy that corn that's going into your car. What's more important, filling up your car with corn or let poor people starve?
Use sugar cane or some other plant that isn't a food staple.
Corn prices have fallen from $8 per bushel last summer to $3.80 per bushel now. Food prices keep going up, however.
Where’s that money going? Profits for food companies. General Mills, Nestle, Kellogg’s, are a few examples of companies who have criticized ethanol but showed increased profits last quarter during our economic downturn.
If they’re simply “recouping” the high cost of commodities by raising prices, they shouldn’t have profits that are actually HIGHER than they were a year ago. They needed a scapegoat to allow them to keep investors happy, and the public bought it.
High corn prices do of course have a slight impact on food prices, but about a nickel’s worth of corn is in a box of corn flakes. The rest is marketing, packaging, brand development, advertising, transportation, etc.
If it gets us off of foreign oil then I'm all for it. We should develop this technology to its fullest potential, but lets remember, our farms also provide us with food so lets be wise and not starve ourselves out of existence making fuel.
Green technologies are on the move because bright young scientists and engineers want to make a difference for a better future. Clean air, clean water and energy independence is the goal. Saving the planet from widespread catastrophy due to global warming from greenhouse gas emissions is a complete mockery of science and the green movement. Sadly, the global warming "crisis" is the incentive used by poloiticians and political advocates to push green technologies. Their pals in the media are quick to push this agenda. Unfortunately for them, more and more people are seeing through the phoney global warming crisis because they don't trust what they see in the mainstream media and are going to other sources of information. If not ,then the politics behind the phoney crisis will eventually erode away the great institution we call Science. We must push very hard to keep the politicians (and the media) honest and open minded or else the green movement will suffer a black eye also.
If private citizens and researchers want to debate GW then thats fine but we should demand fairer reporting of this debate in the media.
Did anyone notice how Al Gore traveled to Washington for his talk at the Capitol? I didn't hear anything so I assume he took his private jet, otherwise the media would have been quick to point out his "eco friendly" travel to Washington to urge congress to pass the stimulas bill to "save the planet".
Great article, except for the "nutritious" cattle feed. Corn is not good for cattle - they should be eating grass. Read Omnivore's Dilemma, it goes into greater detail about the dangers of feeding corn to cattle.
Ethanol is well and good for applications that will be carbon fuel based forever (jet flight, for example).
As far as carbon goes, however, you would get more efficiency out of growing more carbon hungry plants, with fewer water and fertilizer requirement, and just burning them (the ole fashioned way) for electricity to power electric cars.
The energy lost in the fire to electricity exchange is no greater than that used in the corn sugar refinement and fermenting process.
While fire seems like it a barbaric and carbon creating method, remember that both processes pull carbon from the air to return it to the air. A fire plant, however, does so all at one place (the plant) making it easier to filter, store, or power paintballs with.
There are several other advantages to burning stuff:
(1) You are not using food
(2) You can use any biomass (ultra efficents growers, poor soil growers, leftovers from farm production, animal waste, garbage, etc)
(3) Advanced burning techniques (plasma arc burning) do not require dry fuel, don't need water towers and turbines, can be small enough for even portable use and grid hook up, AND can be tweeked to meet the fluctuating needs of the grid (unlike Nuclear's big weakness).
Fire. It was good enough for great great great great (x500) grandfather Ug, and it is good enough for me. If only we had electric cars, that is.
Cottagehunter,
With all due respect, please check your facts.
1. Farmers are not "all changing to corn" - production in the US must rotate between corn and soybeans to balance soil nutrients. The most they can go is two years of one crop in a row.
2. Prices for meat, milk, eggs, went up last year but are coming down now, along with the price of corn. Especially milk prices - the dairy industry is in a crisis at the moment because their prices are so low.
3. People were starving when the price of corn was $1.50 a bushel - demand, infrastructure, corruption and government policies in poor countries have more to do with people starving than the price of any commodity.
from Kent, WA
To my knowledge we still don't have maximum farm acreage in production, as lots of farmers are still being paid by the government not to grow anything, are they not?
There's no way ethanol is ever going to work as a longterm solution for a major part of the world's cars.
Ethanol is destroying the nature by making forests go away for farming which lessens the density of trees in the world which in turns worsens the output of CO2.
The area can be used much better and with increasing population, area is needed. Not even with skyscrapers with farming for ethanol on every floor from artifical light is a long term solution.
Electricity is and has always been the future. E-cars is the perfect concept, only the baby illnesses have to be worked with.
There is plenty of room in the dessert for solar panels and plenty of room on the sea for wind power stations. The sooner we can get our butts up and start this new way of travelling, we can come in harmony with nature and a new Great Time for mankind can come.
from Enfield, CT
Instead of switching more land and resources to growin more corn, we should jus ban high fructose corn syrup. Its already banned in Europe. it is one the main ingrediants in our beverages like gatorade. Its not even natural to our body. Our bodies dont know what to do with that. So ban that and the corn growers can now use it to produce ehthanol instead. Once we make issuses pressing needs instead of ideal wants, then we the problem will be solved. Humans do the most remarkable things.
It seems to me that alot of people are worried about replacing natural land/forest growth with corn fields. I say we'll build up not out. We'll probrably build the corn fields vertically in buildings or whatever like they've been talking about for sometime. So no worries.
from Kent, WA
Eventually all vehicles will be electric, but in the meantime there are over 200 million vehicles on the road in the USA which require liquid fossil fuels. Many of them are not even paid for. Political policies which actually discourage drilling or conversion of coal or oil shale to liquid fuel will make many Americans' biggest personal investment outside of their houses into a worthless eyesore gathering dust in the driveway.
The irony is that this whole over-zealous policy is based on the wrong-headed notion that carbon dioxide (at present .000358% of the composition of the atmosphere) is a major pollutant which is proven to be the cause of global warming, don't you know. After all, a lot of scientists with PhD's and five U.S. Supreme Court justices say it must be true, so don't you know it must be true?
The voice of opposition to the greatest scientific blunder of the last 500 years is only starting to be gather strength. The only real warming phenomenon that GW advocates have to point at is the summer Arctic ice meltback. Recent reports on Antarctica being "proven" to be warming after all were based on fabricated statistical data.
No ice melts in Antarctica because of surface temps in any event and the undercutting of ice by warm ocean currents is limited by the reality that the oceans are not warming in recent years.
from New York, NY
I'm glad to see this report that ethanol efficiency is improving, but the big debate killer is whether we should be using corn or not. We should just render that debate moot by shifting the focus from corn ethanol to hemp ethanol or algae ethanol. Industrial hemp will grow in desert lands where algae won't, which greatly increases the land available to use to farm it, and algae of course grows in the water, so neither one of those alternatives would deplete land available for corn farming, it would increase the number of jobs, because more farmers would be needed, so it's a win for everyone involved.
from Kent, WA
Algae may be the best choice of the three as corn should be conserved for drinking and hemp for smoking to keep the broadest spectrum of voters happy.
Corn has an established infrastructure for planting, harvesting and transport. The farmers are already there and already doing it. All you need to do is build the ethanol plants.
A major challenge for other feedstocks is that there is no infrastructure.
Hemp, for instance. It can be grown in the desert. Great. Who owns that land now and is living there? What are they currently doing with the land? How do we teach them to grow their new crop? How much is the equipment going to cost, and how do we minimize that investment risk so that it actually happens? Who’s going to transport it? How do we entice someone to invest $200 million in an ethanol plant that uses a feedstock that doesn’t exist yet? Or on the flip side, how do we entice someone to quit their job and become a farmer to grow a crop to feed an ethanol plant that doesn’t exist yet? We’re talking billions of dollars here and decades to set it up.
Corn ethanol’s limitations are vastly overstated by the media. It isn’t starving people and by far the majority of research shows a positive energy balance and lower greenhouse gas emissions.
Corn ethanol is a lot better than gasoline. And it is already here, displacing almost 10 percent of our gasoline. Everyone wants to destroy the corn ethanol industry in favor of technology that isn’t here yet. There are great things on the horizon, but if you kill corn and take all that ethanol out of the market, you’re effectively killing cellulosic ethanol and ethanol from other feedstocks.
With populations growing and energy demand ever increasing, how could ethanol fill the gap in our energy needs? In a ethanol scenario, more energy requirements = more land to grow corn. Not all land is suitable for growing, as well as land that isn't laid fallow occasionally will yield diminishing crops. What of a crop failure due to any number of factors such as disease, natural disasters, etc, do we walk? Ethanol doesn't stand on its own as a source of fuel, but as a supplement to oil. This is a poor solution for the long term.
Instead, I think our research money is better spent to harness solar, wind and ocean power for producing electricity. Those technologies can be used for powering all our energy needs including automobiles, and are limitless sources. Leaps are also being made in the areas of energy storage, which means that long range electric cars will soon be a possibility.
Making ethanol makes food prices higher, and actually lowers the fuel economy. What about Cellulostic ethanol?
Fuel for cars or for people ..... tough choice. Corn-based ethanol isn't such a good idea and cellulosic ethanol is a literally tough potential future energy source. Frankly I'm not buying into the federal ethanol craze created in the Bush administration, propagated by legislation, and foisted on the American public in the form of production mandates and 10's if not 100's of thousands of E85 vehicles that give 100% of the (CAFE) benefit to the auto manufacturers and no benefit to air quality (I know because I have such a 'flex-fuel' vehicle that will never see any essentially unobtainable E85). So much for free markets. In the DC area we have 10% ethanol in nearly all gasoline, and still have some of the highest gas prices in the country. As I understand, ethanol is also supposed to be a less expensive means to boost octane; essentially replacing costly gasoline with a cheaper boost. So I pay more and get less (reduced gas mileage). If this isn't an effective lobby I don't know what is. So what are our clean car options. Power an electric from home; tough when more than 50% of us get our power from coal. More diesel in a gasoline-based (US)economy? Not a lot of choices, but ethanol seems to take us down the wrong path. I believe, based on technology improvements over the past 30 years, nearly all fuels can be burned cleaner, the real trick is burn less of it and find truly renewable fuel sources. Hmmm, what do do with all that trash .......
Since both of the cars I own are parked in a rented parking space, I do not have access to a electric source. So a battery powered vehicle, that needs recharged when I get home, would be of zero value to me. So a ethanol powered vehicle makes more sense to me than a battery powered vehicle. Since my yard is used to grow flowers, I do not see a shortage of land for growing corn and other food crops. There are a billion acres of desert waiting for solar powered desalination plants to be built. So there is not a shortage of land for growing food or producing ethanol.
Until production of battery powered vehicles is powered by renewable energy sources, and renewable energy sources are used to charge battery powered vehicles, battery powered vehicles will generate more CO2 air pollution than a gasoline powered vehicle. Now if the automobile manufactures ever make a affordable mild hybrid economy vehicle, powered by ethanol, that I would consider buying. Better yet, a 2 seat in-line ethanol mild hybrid that gets 200 mpg would even be better. Ellen