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Biofuels From Corn Can Create More Greenhouse Gases Than Gasoline
New submitter Chipmunk100 (3619141) writes "Using corn crop residue to make ethanol and other biofuels reduces soil carbon and can generate more greenhouse gases than gasoline, according to a study published today in the journal Nature Climate Change. The findings by a University of Nebraska-Lincoln team of researchers cast doubt on whether corn residue can be used to meet federal mandates to ramp up ethanol production and reduce greenhouse gas emissions."
If oil companies are willing to pay off scientists, start entire shill foundations, websites and TV shows... why would this carry any weight?
As one sided as it might sound, I approach any article or discovery that would improve the oil industries' image or standing with the utmost distrust.
Such as I would to anybody who is willing to give me a secret to riches, phrenology, any religion of any sort, etc.
Surely it's still carbon neutral, given it's from already-present carbon grown from air in the first place (like all plants)?
http://rocknerd.co.uk
It is brain-dead stupid!
How much of the total plant bio-mass are you processing to start with when you are dealing with corn? 2%? 3%? (That is until you get to
the actual fuel, which is much less than that.) When you do Biofuels from farming monoculture the proper way (if such a thing is possible at all), like from sugar-cane, where maybe 30-50% of the biomass is the part to be processed into biofuel, you may be getting some improvement over oil status-quo. With algae you maybe can achieve 100% of the biomass to start processing, sounds even nicer.
But from Corn? It is so stupid, it does not even deserve a proper adjective. It is even stupid to waste time making "studies" on it.
Trying to do it is only about corn super-production, hype, and abuse of government subsidies to plant corn, all mixed with a large, big
dose of the reverse of common sense.
-><- no
If they're counting the carbon to harvest the stalks, then the comparison for gasoline should include the carbon from oil extraction, transportation and refinement. The article also doesn't state if the carbon reduction from plant uptake is offsetting the carbon emissions of burning biofuels. Sounds like they're saying, look at the carbon you get from burning ethanol, add in the diesel to run the tractor, worse than gasoline!
I remember a study by the airline industry trying to claim air transportation was more efficient than high speed trains. This study reminds me of that kind of science.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
The problem is that It isn't a closed carbon cycle. There are a lot of inputs into the process that release carbon. For example what do you think the basic ingredients for fertilizer are?
Biofuels are about government subsidies and nothing more. All the talk about biofuels and the environment is just to trick the rubes.
It's not closed when you are using large quantities of fossil fuels and petrochemical inputs to grow the corn.
There are better feedstocks than corn, for reasons of both environmental impact and efficiency, which also don't drive up food prices in international and domestic markets.
.: Semper Absurda
Corn ethanol was all about trying to win votes at the Iowa Caucus and in California.
There have been papers questioning the carbon savings from corn ethanol for over a decade.
The Brazilian's have been using the claim to promote their ethanol from sugar waste, as have those promoting cellulosic alcohol.
Poor countries and feedlots have complained for over a decade that it drives up grain prices while achieving nothing.
The same thing has been demonstrated for grain ethanol in Australia.
That study doesn't apply if the whole plant is harvested rather than harvesting the Corn stover (leftovers) in a separate process. Seem to be yet another study that damns renewable fuels with faint praise, I wonder who financed such a study.
Anyone who knows anything about Ethanol knows that the two best sources are sugar cane and switch grass. Switch grass should be the choice for North America as it can grow just about anywhere. Corn, on the other hand, takes up valuable farm land, requires more water, and has higher production costs. Ethanol from corn is a nothing but a scam perpetrated by the corn industry. Believe this study or not, but there are much better options than corn...
http://www.scientificamerican....
Why has the US pursued corn biofuels? I thought it was to reduce dependence on imports, not to reduce greenhouse gas emissions.
This is what happens when you trust the Government to solve a problem. They make the problem worse, waste money, and to make matters even WORSE, they tell you to vote for them in the next election to fix the problems they caused in the first place. But sure, Government is the solution to all of our crisis in the future, and we should turn to our over-lords to solve that which ails us, because after all they are soooo darn good at it huh?
Given the vastly superior alternatives to corn for this.
Using Corn for this crap is about as smart as grinding up phone books for ink. Using corn for this is just asking for it to look bad.
Ethyl Burns dirtier than gasolene and has less energy - making you burn even more.
Lets not forget all the secondary Carbon/Polution creation cause by producing it in the first place.
SO dont forget to tell all your ignorant eco-greenies that they are being taken for a ride and really need to look into these scams they believe in.
The amount of released CO2 simply does not matter because when the plant regrows it will absorb exactly the same amount again.
The only question is the total amount of CO2 in the biosphere, not the output of single reactions inside the biosphere. Reducing the total amount can be either done by "growing" more CO2 containers or store CO2 by industrial methods eg underground. The later sounds strange but works pretty well, a single plant with a 10MW power source can easily outperform a 100km forest in CO2 reduction.
"Life is short and in most cases it ends with death." Sir Sinclair
There are no scientists in government. Nearly none in the environmental movement, and the few that are have shown themselves to be committed to keeping the global-warming gravy-train going at any cost. They are all, therefore, prone to grab at the first idea that comes along, mandate it, ram it down everyone's throats, expend vast sums of money in the process, only to discover it won't help anyway, or even makes the problem worse. We saved far more CO2 with fracking than any number of other hare-brained schemes from the looney left and now that's the next thing they want shut down. This study shouldn't surprise anyone who has bothered to look at the history of the players involved.
#1 Get the gov't out of it.
#2 Get the UN out of it.
#3 PRIVATE INSTITUTIONS RAISING AND SPENDING THEIR OWN GOD-DAMN MONEY SHOULD THEN:
#4 Let responsible climate scientists fight it out - on the internet, not in the journals - until a real consensus, unaffected by emotional advocacy groups who really only oppose things because their self-designated opponents are evil people, not because they really care one way or the other about the issue at hand.
#5 Determine if the warming is significant enough to have measurable effects and that those effects outweigh the good effects they may cause as well.
#6 Determine what the best return on investment is for proposed courses of action, start small, define success criteria and stop if it doesn't meet them.
#7 See #1-#3 again, and immolate any lawyers or politicians who interfere.
There are two major reasons it DOES matter, as explained in TFA. First, much of the CO2 is not from burning the ethanol, but from producing it. Imagine if the tractors, stills, etc. burned four gallons if diesel to produce on gallon of ethanol. Every gallon of ethanol you put in your car caused four gallons of diesel to be burned. That's the concept, though of course it's not quite that simple.
Secondly, it isn't the total amount of carbon that matters. There is always the exact same amount of carbon on the planet, modulo meteorites. The problem with fossil fuels is that they take carbon out of the ground and put it into the atmosphere. It's carbon in the atmosphere that's the problem. Corn ethanol does the exact same thing - carbon from the ground goes into the corn. When you burn it, that carbon ends up in the atmosphere - just like burning gasoline.
Contrary to what ignorant people believe, oil companies actually love the mandated 10% ethanol.
E-90 (10% ethanol blend) has the side effect of dropping the MPG of ANY vehicle by at least 20% ... meaning that you have to buy more gas ... and pay more for it.
Using food crops as fuel is immoral. Our ethanol program has made the price of food go up just not here but in countries whose people can ill afford to pay more for food. It needs to go away now. There is plenty of oil in the ground for a long time.
Well of course biofuels from corn create more greenhouse gases than gasoline. It is not cost effective to dedicate corn into the production of synthetic crude oil when organic garbage can be used.
If you are having problems with a gas lawnmower, chances are the cause of the problem is the fuel you are forced to put in it.
No, the problem is the manufacturer of lawnmower engines are cheap and unconcerned about actually doing things right, so they continue to make shitty engines i China and import them here, and they're happy when they only last 4 or 5 years.
Most of the Carbon in the plant comes from Co2, not from the ground numb nuts. That's what plants do, they convert Co2 into biomass.
Slashdot is becoming a corporatists plaything. Filled with tech naives who would die in the dark without electricity after an EMP. And wouldn't be able to thing of anything else but the present paradigm. What a sorry read that was. Oh, by the way, I did try to be equitable, generous, patient, tolerant. After having it pester me so persistently, now I, too, *Curse Beta*!
Most of the corn grown in the US is used to feed cows. Cows (via their symbionts) eat the wood and protein. They pass most of the starches. Which is what yeast likes. And uses to make alcohol. You can ferment corn to make alcohol. What's left is great for ruminants like cows. And the yeast remains provide protein and minerals. And much more starch productive plants - like milkweed - can be used to help clean up the cow runoff (that isn't used to produce gas and fuel).
Plus, whatever the emissions per fuel expenditure is, it doesn't include sending hendreds, I mean, hundreds of thousands of people thousands of miles away from home, to kill and die and drill and bring it home, and refine and lug it around. Until every gallon actually burned in the engine costs 3 or more to get it there. And the cost of destroying whole countries and cultures just for some lobbyists and politico's payoffs.
The study doesn't make sense. It's cherry picking a low return case.
Unfortunately, no. You may be aware that the air is 79% nitrogen, yet fertilizer is mostly nitrogen, because plants take nitrogen from the soil , not from the air. Corn does the same with carbon. That's one reason that corn is a stupid way to produce ethanol and switchgrass is a better choice.
Corn (maize) is one of the worst possible plant masses you could grow to make biofuel. It's horribly inefficient compared to other crops.
We've always known this. And it drives up the price of food. Globally.
Why are we still using corn to make ethanol? Farm lobby.
You insensitive clod!
Even a 10 year old looking up the statistics would have picked beets or sawgrass or hemp over "Corn" for bio-fuels.
Corn is ridiculously low output for alcohol per acre and freaking retarded as a Diesel-oil replacement.
Hemp seed oil runs in diesels... no modification. Grow it cheap, press and filter the oil out of the(billions of) seeds and put it straight in your diesel tank. CHEAP!
Biofuels from corn.... What a ripoff!
Go ask any mechanic who deals with vehicles that run on Biofuels such as BioDiesel, Green diesel, Bioethanol or >10% blends and you will find that they often clog up the injectors so badly that they need to be replaced (injector) 45% more frequently (adjusted % based on time injector was installed and comparing same brand part durability on the same vehicle until breakage).
That may not seem like much to some, but for those running public transportation and school buses, the political "go green" machine ends up including a hefty maintenance charge, metal waste and labor... All this atop of added air pollutions.
Since the energy required to produce corn ethanol is nearly equal or sometimes greater than the energy gained as fuel, corn sucks. It should be obvious that you are going to produce more emissions with corn. Even when the tarsands require large amounts of refining, that tarsand oil will be used to produce corn ethanol. Oil is used today in corn agriculture and production of ethanol. Corn as a biofuel is an odd stop-gap. If we have to use subsidies, why not encourage farmers to make some other crop that transforms to oil with higher efficiency?
This was very well-known, long before the effort even began. There was plenty of research on this back in the seventies and eighties, but the big agri-business corporations were going around buying-up family farms and buying politicians to get the politicians to pass laws REQUIRING people to buy a fuel additive that only the big agri-businesses were gearing-up to make. Don't you "green" activists pay ANY attention to who is funding all the anti-"Big Oil" propaganda??????? Probably not, since so many of you seem not to notice all the Arab oil money that poured into the anti-frakking campaigns.... (hey, what Arab oil minister wants Americans moving from Arab oil to domestic American natural gas?) Move along, nothing to see here...
The simple fact is that fossil fuels are like meat in one important way: They are highly-concentrated forms of energy created through time and complex interactions of lower-concentrations of energy. (VERY) Simply put: the grazing animals spend all their time wandering the plains eating grasses and putting meat and fat onto their bones, and the big cats come along and get the energy they need from a quick meal of meat (indirectly getting the energy from all that consumed prarie grass). In a similar manner, you can inefficiently convert a huge bunch of green vegitation into fuel for your car (barely getting more energy out of the process than you put into it, and consuming lots of water and cropland in the process, thus driving up food and water prices), OR you can let mother nature (at her expense, not yours) condense the energy from plants and animals that died long ago (using time, heat, and pressure) into very dense "fossile fuels" for you and use them. Oh, and since mother nature went ahead with the process without asking you first.... the "harm" has already been done... the carbon products exist; leaving them in the ground does not make them "go away".
It takes an idiot to always choose the inefficient low-energy path, particularly if the supposed "benefit" is the hope that someday the planet might be half a degree cooler during an interglacial period.... if the current crop of fortune tellers are using their wands correctly... and assuming your descendants won't mind entering the next ice age a few years early.
If farmers were not forced to destroy their alcohol stills in the early days of Prohibition we would have known long ago about the viability of biofuels. Almost a century ago farmers would make ethanol for use as a fuel to run tractors. No doubt they'd also drink some of it, or sell some of it for others to drink. Prohibition destroyed the hobbyist experimentation of ethanol as a fuel. It made any use of ethanol a legal nightmare.
When Prohibition was lifted it didn't improve things much. Ethanol production was tightly controlled for anything beyond what the government deemed as "private use" amounts. This held up ethanol fuel experimentation until the 1970s. Even to this day no one would even consider ethanol as a fuel without the blessing, and a big pile of cash, from the federal government. Anyone doing otherwise runs the risk of jail time for "bootlegging". Something I'm sure is enforced as much by the whiskey producers as it is from the people that get the big piles of cash from the government for biofuels.
There's all kinds of things we could have learned if it wasn't for crushing taxation and regulation by the federal government. It's not that I'm some sort of anarchist. I think we need a strong government. If the federal government was truly interested in finding energy solutions they'd have to look at what laws are in place which prevent experimentation.
If the government wants people to experiment with, for example, the effects of ethanol on modern internal combustion engines then they'd have to make it possible to manufacture the ethanol without two full time lawyers and a dozen clerical workers. But the government is not interested in finding energy solutions. The government is interested in buying votes.
If the government was interested in finding energy solutions they'd also let people build nuclear power plants. I believe ethanol to be a dead end technology. Prohibition prevented us from figuring that out nearly 100 years ago. So, we'll have to go through the motions, and piles of my tax money, to prove it. Then what? We'll have to go through nearly 100 years of no effective research in nuclear power to figure out that it is possible to make safe, cheap, and abundant, nuclear power.
To those that think nuclear waste is some sort of unsolvable problem I say you need to look up waste annihilating molten salt reactors.
I am armed because I am free. I am free because I am armed.
The only real winner from corn ethanol is giant agribusiness companies who produce the GM corn seeds, sell the massive amount of chemicals the corn requires and makes ethanol from the result. It does nothing to reduce green house gas emissions. It does nothing to reduce the dependance on foreign oil (especially given all the oil-derived products required to grown that corn including the diesel for the tractors and harvesters). And it probably doesn't put all that much extra money in the pockets of small corn farmers.
Ethanol from hemp or switch grass or any number of other plants is much better for the environment, doesn't require anywhere near as many inputs, can be grown on land that other stuff wont grow on, can genuinely reduce dependance on oil (foreign or otherwise) AND can reduce green house gas emissions. But there is no "Switch grass lobby" to fight the corn lobby so everything is pushed to corn ethanol and the planet is worse because of it.
I remember reading this argument like 10 years ago. I don't know if it is true, but it seems reasonable... all things being equal, it would take a lot more work to get a diesel fuel out of corn than crude oil.
But the true stupidity in using corn for fuel is using food as fuel. That just pushes food costs higher. Consider that there are a lot of other cleaner ways to make bio-diesel that don't compete with the food supply, it is hard to pin this study on the oil companies. Corn for bio-diesel is just more government kickback to the corn industry, and the ridiculous subsidy corn farmer get for bio-diesel.
90% Ethanol fuel will eat just as much at your fuel system as 10% Ethanol will. The big problem is that older cars (we're talking over 10 years old at least) may have materials in their fuel system that aren't able to deal with ethanol. Old rubber hoses will perish, fuel pumps with rubber seals will go the same way. 90% Ethanol would be hard to start in cold winter region, which is why E85 is usually the highest concentration used in vehicles
I was promised a flying car. Where is my flying car?
The only purpose of the whole corn ethanol debacle is to transfer vast amounts of money from the taxpayers and the gasoline-buying public to Cargill and Archer Daniels Midland. Any other claimed purpose is, and always was, bullshit.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
It's only a problem if you are taking too much of the plant away from the field. Growing corn isn't the problem, growing corn and carrying away the waste instead of turning it in is the problem. Corn still gets most of its carbon from the air like every other plant.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Seen the price of meat lately? Hmm? Bacon? Beef, perhaps?
We paid $4.39/lb for 90/10 ground at the local processor last week. At Walmart yesterday it was $4.99/lb.
Bacon is still outrageous, too.
The media blames heavy rains or droughts or whatever, but none of it is true. It's all because feed prices are skyrocketing with the price of corn, because we're stupid enough to use our food to make dirty fuel for our cars.
A 10% ethanol blend with regular gas means a 20% loss in MPG on any vehicle. The loss is higher on less efficient engines.
-1, wrong
Oh, you mean carbon dioxide, that deadly poison... Idiots.
Please stop repeating this braindead 'catastrophic man-made global warming' mantra. Saying it over and over and over doesn't make it real...
www.climatedepot.com
I fully understand your doubt.
For people who have no idea of what it takes to grow plants commercially, they have no idea what the chain of support industries whose whole existence is to make the whole process more cheaply, and to get the "harvest" to market as fast as possible.
And in order to do so, they have to use a lot of resources - resources such as fossil fuels - to make it possible.
Everything from the making of the fertilizers, to the packaging of the fertilizers to the transportation of the fertilizers to the farms, to the pesticides used (and the making and transporting of the pesticides) to the harvesting to the, in the case of corn and palm to sugar cane and the turning of those commodities into biofuel --- all those consume massive amount of fuels.
You won't understand the full extent of the agricultural business until you are in it, and I am in the midst of it, right now.
I have largely exit the high tech field and right now most of my investment is in agriculture - I can see the stupidity of the insistence on the use of biofuel.
The only way to cut down on the carbon footprint is to USE LESS. The biofuel thing is nothing but a big sham !
Muchas Gracias, Señor Edward Snowden !
I started to mention that and link to a study that measured soil C, but the rude AC didn't merit it. As you said, growing corn for food kernels and tilling the rest in is fine. The amount of carbon that comes out of the soil is roughly equal to the amount that's in the leaves and stalks, so tilling those back in makes food production roughly carbon neutral. If you take those tillings to make cellulistic ethanol, then the soil carbon is reduced. The carbon that was in the soil ends up in the air.
Of course none of this occurs on other planets, which are also warming, but that's another discussion.
I think using ethanol is basically retarded. We're using fossil fuels to do a bunch of farming to produce a bunch of fossil fuels with lower energy density than the ones that went into the farming and doing so basically as a subsidy to corn farmers. Stupid policy.
That said:
1: HFCS. Enough said.
Which has exactly what to do with ethanol? HFCS is a function of price supports and import restrictions for sugar. HFCS is cheaper as a result. Take away the price supports and the need for HFCS will drop. All of this has precisely nothing to do with ethanol policy aside from the fact that corn growers benefit from both products.
I wish there were concrete figures if using for ethanol takes food out of hungry people's mouths.
Ethanol production isn't at such a level that it causes starvation. There is no lack of reasonably priced food in the USA (see obesity crisis) though in some cases there is a distribution problem.
Food prices sure jumped when ethanol was mandated in the US in gasoline.
Citation please. I oppose the use of ethanol as a mandated fuel but I've seen no evidence this has occurred. It's certainly *possible* but that's not the same thing.
3: Ethanol does a number on small engines.
Only engines that weren't designed for ethanol. Again, our ethanol is a dumb thing to use as a fuel for the most part but that doesn't mean it cannot be used without damaging a properly designed engine. It's old engines that weren't designed with ethanol in mind that are the problem. It's like dumping a small amount of diesel into a gasoline engine. Might run but it's not good for it.
Methanol would be a much better choice, since it can be made from any biomass, not just starch or sugar.
That does not the same thing as saying you can create a net energy increase from methanol or that once all factors are accounted for that it is less polluting than just refining oil directly. Modern agriculture essentially converts oil into crops - both from fertilizers (which are oil derived) as well as transport and planting/tending/harvesting. With ethanol/methanol you are converting the crops back into oil products. For that to make sense you have to establish that there is somehow a net usable energy gain and/or that it is net less polluting from the oil-alcohol-fuel cycle than the oil-fuel cycle. I've seen no credible evidence that the oil-alcohol-fuel process is in any way more efficient or less polluting on a net basis than just refining the oil directly to fuel.
Such a requirement would change the market. With millions of cars able to use it, gas station owners would start selling methanol on one or two pumps. This would effectively break the current monopoly that petroleum has on transportation fuel.
How do you think methanol would be produced at industrial scale? Farming at industrial scales requires oil and lots of it. It not only would not break the cycle there is a very strong potential it would make it less efficient and more polluting than it already is AND it would tie up arable land for fuel instead of food.
There are better feedstocks than corn, for reasons of both environmental impact and efficiency, which also don't drive up food prices in international and domestic markets.
They still require arable land, oil, fertilizer, transport, tending, harvesting, refining and more. I've not seen any biofuel based on planting and harvesting crops that shows credible evidence of being more efficient than simply refining the oil directly. It sounds like a good idea (plants = green, right?) but once you account for the entire system it simply makes things more complicated and sometimes more polluting with no actual improvement at the end of the day. Sure there are plenty of better feedstocks than corn but at the end of the day that isn't the fundamental problem. The fundamental problem is establishing how oil->alcohol->fuel is more efficient and/or less polluting than oil->fuel directly. Any data that doesn't address that question is a waste of money, brains, oil and time.
...Biofuels were *meant* to reduce greenhouse gas emissions.
Alternative (to petroleum) fuels fit into two categories:
1. Those meant to reduce greenhouse emissions (like electricity)
2. Those meant to reduce our 'dependence' on foreign oil (like biofuels)
The first only works if energy production emits fewer greenhouse gases than the fuel it's replacing.
The second was never intended to reduce greenhouse emissions at all.
So why is it news that a carbon-based biofuel and carbon-based petroleum fuel emit similar amounts of carbon dioxide?
Using any kind of food as a fuel, only results it a predictable and perpetuating food price increase. one bad season on the crops, and big surprise, the food and gas prices both go up.
Who do you think profits from that?
IF we've been fucking around with electric vehicles and solar just gets better and better, then why the hell are we taking away from the food supply to make "gasoline" while global warming keeps telling us that food prices and riots across the globe will be on the rise? On top of it, let's use one of the main sources of food and make gas out of it. Brilliant! Absolute genius.
Methanol can be made from perennial crops which can be harvested economically with little to no inputs.
Perennial crops still need water, pest control, harvesting, tending, processing, and some amount of fertilizing, ALL of which require oil and other petroleum products. Methanol would likely be a big improvement on ethanol but it doesn't solve the fundamental problem of eliminating the need for oil inputs and it's not even clear if it would get the need for such inputs below the energy output of the methanol produced. I don't have any problem with using methanol as a fuel source (at least no more than any fossil fuel) but so far the thermodynamics and economics of it just don't seem to make any sense other than as a supplemental or byproduct source of bio-fuel. Replace oil? Not going to happen.
Without tillage, such crops can be raised on lands which are currently considered marginal or unusable for conventional row-cropping. So methanol (unlike ethanol) would not compete with food crops at all.
It might help a bit at the edges but there are reasons we don't use those locations beyond just the soil quality. Difficult landscapes, poor irrigation, remote locations, etc. And if there is money to be had, it will compete with food crops to some degree. The only question is how much.
It already is produced at industrial scale. It's one of the most common "industrial" chemicals on the market. Unfortunately, a good chunk is currently produced from natural gas
A "good chunk"? Try the vast majority. There is essentially no industrial scale bioreactor on anything close to the scale relevant here. Right now the total capacity for methanol production in the US is 2.6 billion gallons annually, most of which is made from natural gas. Compare that with the 133 billion gallons of gasoline consumed in 2012. That doesn't even count diesel and other fuel products from oil.
Corn's incredibly harsh on the soil. It annually needs a lot of fertilizer (that is, modern corn). Biofuels - pretty much everyone before the corn lobby got into it was talking lots of other, easy, fast-growing *weeds*, like switchgrass comes to mind. No fertilizer, etc... I mean, it's a *weed*.
But agribusiness industry (petrochemicals into fertilzer, for example) aren't interested in *that*....
mark
The University of Minnesota reached that conclusion a long time ago not to mention other tangent nasties such affecting food prices and using a LOT of water in the process. Duh.
Different forms of ethanol have different impacts.
Ethanol from crops that would have been burned creates a net zero GHG impact, especially that from cane sugar production.
Ethanol from actual corn, due to the high water and fertilizer content, and the fact it is diverted from feed crops for animals and humans, has a high GHG impact, and actually costs more to turn into ethanol, in terms of GHG impact, than if used for feed.
Ethanol from switchgrass and blue-green algae is fairly good, with a net positive GHG impact. Switchgrass is a rotation crop, so it has very low fertilizer and water needs, and converts fairly well. Algae does have high water requirements, but if produced in areas with high water content, or used as a filtration crop to clean polluted water, can be a net positive.
But corn ethanol ... that is a bad choice.
(caveat - I invested in various corn ethanol IPOs at various times)
-- Tigger warning: This post may contain tiggers! --
Engines required a nontrivial amount of reengineering of their plastic and rubber parts when ethanol was introduced because ethanol is a mixed polar/nonpolar organic solvent. Methanol is a significantly more powerful solvent than ethanol, and I dare say that there is a [citation needed] on the claim that dealing with the problem costs only $100 at the factory.
Mind, the solvent-ness decreases as you insert CH2s to the chain, which is why you can go and put straight butanol into a diesel car's tank with no change other than buying a performance fuel pump because the stuff's more viscous than diesel. However it is true that making the bacterial goodies manufacture longer-chain things is more difficult and absent a breakthrough biobutanol isn't taking off.
We've known for a long time that ethanol is a polluter. Yes, it lets us recycle CO2, bu that's the only good thing about it. Besides, it takes land out of food production and reduces food for animals, raising meat prices.
Not fucking surprising, eco-loon ideas nearly always don't work quite as the dumb shits think it will.
They just don't have knowledge they think they have and are too far gone with the fairy's in their utopian green eden shit.
That reality always smack's em in the face with a 2x4