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What about Ethanol?

What about Ethanol?

What about Ethanol?

I try not to be cynical >BUT< I am not seeing a technical benefit to Ethanol.
1. It takes as much energy to make as it returns. There are precious few eco-hybrid tractors and combines out there plowing and harvesting the cornfields, but plenty John Deere Diesels.
2. Cars get poorer mileage so the cost per mile increases when burning E85 or even 10% ethanol.  
3. Displaces farmland used to grow food: THe price of corn has already risen noticebly
4. CO2 and Water vapor are both produced by ethanol combustion. Even the H2 Fuel-cell lobby has dodged the observation that WATER VAPOR is a more potent greenhouse gas than almost any other component.  
5. Vast quantities of CO2 produced in the fermentation process.
6. Ethanol plants are being built with the cheapest (and no, I don't mean least expensive) components. This suggests that the ethanol manufacturers expect it to be a short-lived demand and want to grab the quick bucks up front. Also implied is a sacrifice in safety.  
7. Residual corn products after ethanol production are converted to Cattle Feed, (also at a high cost of energy in drying, packaging, and transportation, and methane production in bovine flatulent discharge.)

SO as I see it the Birkenstock crowd gets to feel good when they narrowly define their system and they just measure the specific exhaust components of their prius after filling the tank with E85, but in reality a tank of E85 does more harm to the ecosystem/planetary entropy balance than a tank of Sunoco 260.  

I'm open to reeducation, but there is more to ecology than wearing tie-dyes and singing coom-bye-ya.  
Next I will rant about the ecological footprint of compact fluorescents vs traditional incandescent bulbs.  

RE: What about Ethanol?

I don't understand how statement number is possible....

  Energy OUT = Energy IN

This implies 0 losses, right?

RE: What about Ethanol?

Ethanol fuel makes no sense if you do the math.  But, since when do politicians and greens do math?

RE: What about Ethanol?


I have to agree with you. It doesn't make much sense to me either. If I remember correctly the ethanol component of E85 is also corrosive, so it can't be premixed and transported through pipelines. This further reduces the economy of E85. Also, it does not seem prudent to use our food sources as fuel. The price of corn has risen greatly. So has the price of everything that needs corn (beef, milk, poultry, etc.). Further, many farmers are growing corn rather than their usual crops, raising the prices of the other crops. I think the transition to ethanol has a lot more to do with the agricultural lobbiest than it does technical merit. Many accuse our politicians of being under the influence of "Big Oil". We may be trading "Big Oil" for "Big Ag".

With all of that said, I do think there is merit in ethanol that is produced from other non-food sources.

RE: What about Ethanol?

Ethanol is wonderful when incorporated into beverages!

RE: What about Ethanol?

Melone: I will embellish.  The amount of fuel consumed in producing one liter/gallon/barrel of ethanol costs almost the same amount of energy that the end-user finally receives from the same quantity of ethanol.  Might just as well have a diesel Prius and save everybody a lot of bother with plowing, fertilizing, reaping, etc.  

RE: What about Ethanol?

That ethanol is a zero sum gme with respect to the displacement of fossil fuels is a bit of a myth based on a flawed analysis done by Pimentel and others.  If the brewer's mash byproduct of fermenting the feed grain is simply wasted, then the calc definitely works out that way.  If you take credit for the energy benefit of feeding the brewer's mash to cattle, then ethanol comes out at least modestly positive in terms of reducing greenhouse gas emissions.  As to whether or not it does so on a sustainable basis, or an economical basis without subsidy, that's a matter for debate.

Ethanol is also an oxygenate when blended with gasoline, reducing harmful emissions in a safer way than previous additives like MTBE.

But the big problem with ethanol is that it's a distraction from the real work that needs to be done:  we need to get people out of cars, and reduce the size and increase the efficiency of the ones that are left.  By and large, ethanol is agricultural subsidy masquerading as energy policy.

RE: What about Ethanol?

But the new issue is the methane from cows, now what do we do with the left over mash.  The microbrewerys in my area (4 in a town of 15,000) are under fire for the high BOD in their waste water.  It goes on and on.....  

My Chinese boss say: Tiger from west mountain eat you the same as tiger from east mountain.

RE: What about Ethanol?

Other than extending the gasoline supply, I do not see the logic or benefit of Ethanol.  With my Prius, I was getting 51 mpg this summer.  Now, with the inclusion of the Ethanol for winter driving, the rate has dropped to 44.5 mpg, and not all of that is due to the heater running.  That's over a 10% drop.

Mike McCann
McCann Engineering

RE: What about Ethanol?

A 10% drop in fuel efficiency during winter is peanuts. Depending upon the winter conditions, even 40-50% can be experienced. I doubt the ethanol mix plays a big part.

In every vehicle I've had while in Ontario, I've experienced substantially larger drops during winter ... without changing gasoline types. The worst case was about 25-30% in a Chev Malibu.

Running the heater in winter probably takes as much as the A/C in summer.

Colder engine taking longer to warm up to optimum temperature.
Similarly transmission and wheel bearings.
Lower tire pressure.
Extra weight of snow or ice or slush buildup on the car.


RE: What about Ethanol?

"By and large, ethanol is agricultural subsidy masquerading as energy policy."

moltenmetal, a star for that statement.



RE: What about Ethanol?

A star for you Moltenmetal, from me as well.

You make a point for Ethanol that I hadn't though of - ethanol primarily for its benefits as an additive and not pirmarily as a fuel.

Unless you're in a country like Brazil, were the policy is one of avoiding the import of fuel and the ecomonic balance-of-trade issues, ethanol doesn't make much sense from a strictly fuel standpoint.

However, because there is a small demand for ethanol, economically, there is a push to research and investigate the ethanol alternatives and improvements that might well result in new methods and discoveries. But if it turns out there is nothing significant to be discovered, then it will remain a minor energy technology.

RE: What about Ethanol?

Up until recently the feedstock for industrial ethanol was... oil.

Maybe that has changed.

But I think that says it all.


Greg Locock

Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.

RE: What about Ethanol?

MTBE was mandated by legislative fiat. Then OOPS!,  MTBE is more toxic than the tetraethyllead that was outlawed, rendering MTBE necessary.  But somehow that's the fault of the evil petroleum industry, not the incompetent politicians who demanded it.  Now they just raised the CAFE standard by some silly amount.  Maybe they could just pass a law changing F=MA to F=MA/2, and that would just about fix the ability of the evil carmakers to meet the new CAFE standards.  It'd be at least as effective as when the Indiana legislature tried to change the value of Pi to 3.  

RE: What about Ethanol?

I seem to be running into some forum rule since my posting needs to be split into two sections for it to be accepted, so here goes section 1.

I think we must be asking the wrong questions. An economic analysis, setting aside the subsidies, does not capture the strategic and environmental aspects, but should be done. The "net energy in versus energy content of ethanol produced" calculation does not seem to have a single solution for various reasons. 1) Do you count the fuel used by the guy driving to work to run the plant? 2)How close are the cows that are going to eat the Distillers' Dried Grains with Solubles (DDGS)?  3)Do we capture the methane from the cows (not my job) as a fuel benefit or a global warming disbenefit? and so on.

HAZOP at www.curryhydrocarbons.ca

RE: What about Ethanol?

Here is section 2

When dealing with co-products (not by-products) it is not possible to calculate the cost of manufacture of one of the co-products. This has been demonstrated to various governments over the years. However most politicians don't realize that we can't calculate the cost of gasoline. Its the same problem as calculating the cost of ox-tail soup - it depends what you get for the rest of the ox. So we probably should be doing some kind of comparative analysis to determine solutions to our problems. We probably need to simulate the economy over a long period with various energy options.

One useful compilation of data can be found at http://www.ethanol-gec.org/corn_eth.htm . This paper is by the agriculture folks and the conclusions are strangely detached from the data. However the tables and most of the text are informative.

HAZOP at www.curryhydrocarbons.ca

RE: What about Ethanol?

Switching the US over to ethanol is like switching a junkie to methodone,you are just substituting one addiction for another.

It is definately best to increase fuel economy.

RE: What about Ethanol?

Forget about the methane from the cows, as it's not part of the fuels equation.  That cows emit methane has nothing to do with the ethanol and everything to do with the energetics of food production.  The real greenies are veggies as well, and I'm talking about their food choices rather than their intellect!  What you displace with the brewer's grain is straight feed grain- there is no impact on the methane output of the cows.

How close is the brewer's mash to the cattle?  The ethanol plants are now often co-located with cattle feedlot operations, so I'd say that was close enough.

RE: What about Ethanol?

By rasing the price of corn, dosen't the goverment reduce the amount of farmer wealfare given?

RE: What about Ethanol?

cranky:  you've got a point, but do you really think that there's a net reduction in money out of government coffers and into the pockets of farmers as a result of ethanol production?  Doubt it seriously.  Ethanol does sop up some of the (enormous) excess agricultural capacity in the US, which does drive up the prices such that we all pay more:  that's good, because grains were WAY too cheap before.  The farmers earn more, so they pay more in taxes.  It definitely benefits farmers, which isn't a bad thing- better them than giving the money straight to ADM, Cargill or the like!

One thing is sure:  the Europeans and others, who have complained bitterly for decades about US agricultural subsidy policy (while maintaining their own, similar subsidies), are much more favourably disposed towards agricultural subsidy related to ethanol production than they are toward similar subsidies for food production.  Corn made into ethanol is no longer available for dumping on the world markets.

RE: What about Ethanol?

I found something interesting regarding this topic.

I browsed through the site and clicked on a link that said "busting the ethanol myths".

Here it is.  


This guy either thoroughly researched this topic, or is one whacked out hippie (maybe both)

RE: What about Ethanol?

From the permaculture site:

"Even if, for alcohol production, we used only what the USDA considers prime flat cropland, we would still have to produce only 368.5 gallons of alcohol per acre to meet 100% of the demand for transportation fuel at today’s levels."

Cool!  Forget about all of those other crops.  Grow them on the marginal land and devote the prime land to ONLY alcohol production!
Who needs food? Sounds logical to me ponder

Believe it if you need it
or leave it if you dare

RE: What about Ethanol?


- You're assuming that nothing grows on the "marginal" land.

Remember that "prime" cropland is only HALF of the TOTAL agricultrual farmland.  

So going by what you said, we would only use 46.2% (434,164,946/939,279,056) of our total crop land to farm fuel.  

I'm sure we could grow SOMETHING out of the other 53.8% of the total agricultrual land.  It's not like the "prime" land is very fertile soil and the "marginal land" is a bunch of rocks.  I'm pretty sure that if regular people who have gardens in their back yard can grow more vegetables that you can shake a stick at on less than an acre, we probably won't need to worry about food vs. fuel. Because if some average joe can grow enough crops in his back yard to feed the neighborhood, then I'm confident that the professional farmers can grow enough to feed the nation on "marginal" lands.  


RE: What about Ethanol?

Sorry, that was supposed to be tongue-in-cheek.

Believe it if you need it
or leave it if you dare

RE: What about Ethanol?

sorry, I can't pick up on tongue-in-cheek on forums.  

RE: What about Ethanol?

So why are we only using corn? Why can't we use sugar cane, or sugar beets, or sorgum, or apples, or several others.
The fact is what we buy in the store are the good fruit. What happens to the not so good fruit, and slightly spoiled grains, or out-of-date candy, the not humanly eatable grains?
I guess we just toss them in a landfill.

RE: What about Ethanol?

No, a lot of it goes for pig food.

RE: What about Ethanol?

A lot of it goes for pig food but it has to be cooked first.
The feeding of garbage to pigs has been outlawed.

Until the introduction of the moderen hog concentration camps,  Los Angeles had the largest hog ranch in the world. Garbage picked up daiily in LA and there abouts was sent to east of town and fed to hogs. It was outlawed in the early 50s I believe.

RE: What about Ethanol?

I understand Brazil is using sugar beets for ethanol production because it yields more ethanol and uses less energy to produce.  However, I understand they have an almost non-existant farm lobby.

Don Phillips

RE: What about Ethanol?

I think I brought up the issue of beats in another previous post on ethanol or something cranky108.

Other than the 'big corn' issue (all the subsidies, ingrained culture etc) is there some other reason/s why they are using corn not beats?

I tried to find out if beets are more energy dense than corn but a quick google didn't give me a conclusive answer although it suggested they were.  Also I'm not sure if more or less land is suitable for beets etc.  Then there's the possible issue of if combines and other equipment are readily available for corn while there may not be as much beet equipment around etc.

Either way, the corn thing just seems like they're using it because there was a glut of it making it cheap, not necessarily because it's the best candidate.

As to why not to use cane, I don't believe cane generally grows well further away from the equator.

Perhaps butanol is a better alternative? http://www.technologyreview.com/Energy/18443/

KENAT, probably the least qualified checker you'll ever meet...

RE: What about Ethanol?

Er, they grow sugarcane in Brazil, not sugar beets...Sugar beets were an alternative to cane sugar which we could grow here in North America.  The majority of the world's sugar is derived from cane, not beets, for a reason:  cane's a cheaper source.

The reason they're using corn in North America is that the grain itself is an inexpensive source of starch which is basically polysugar.  The fermentation bugs are just as happy to digest starch as sugar.  The cellulose in the corn stalks, not so much.

RE: What about Ethanol?

I believe there is an important point which seems to always be missed in the ethanol debate.  Although I agree that corn ethanol is not going to be an economically viable alternative to gasoline in the long term, what we have with ethanol is a chicken-or-the-egg problem.  In order to develope viable sources of ethanol, significant investments will have to be made.  However, if no ethanol vehicles are on the road, if no distilleries exist, then no return can reasonably be expected on investment into improved production technology.

If existing distilleries can be retrofitted to incorporate new technologies as they come available, reducing the true price of ethanol, and cars are on the road ready to burn the fuel as it becomes cheaper, then there is incentive for investment.

RE: What about Ethanol?

youngturk:  you're confusing ethanol with hydrogen: there's no chicken and egg problem here.  Ethanol works just fine in ordinary internal combustion vehicles as long as you add at least a little petroleum gasoline.  There's a ready market for the product.  There's no special infrastructure, aside from the construction of the production facilities themselves, required to utilize ethanol as a fuel.  There are minor problems with the distribution channels (ie. pipelines designed for mineral gasoline etc.), but these are truly minor when compared with the challenges associated with alternatives like LPG much less hydrogen!

People have been making ethanol for millenia- it's the definition of a "mature technology".  Order of magnitude improvements in the energetics of this technology are unlikely.

It would be best if we'd all just STOP holding out hope that we can continue with "business as usual" as far as the personal automobile is concerned.  There's no magical technological fix out there to make the fossil fuel dependence of the car just go away.  We can make cars smaller and more efficient and use them less- that we can do- but we'll only do that if we're forced to by fuel price:  that's a fact.  Until we fix the far easier problems related to fossil fuels use- the ones associated with non-moving users of energy (ie. heating and electricity generation)- there's absolutely no point to even trying to mess with transportation fuels.

RE: What about Ethanol?

moltenmetal, not sure who your first few lines were aimed at "Er, they grow sugarcane in Brazil, not sugar beets...Sugar beets were an alternative to cane sugar which we could grow here in North America.  The majority of the world's sugar is derived from cane, not beets, for a reason:  cane's a cheaper source."

I don't think anyone implied they were growing beets in Brazil or did I miss something?  Also part of my point was that when it comes to making sugar Beets are the cold weather alternative and hence, when it comes to making ethanol should they be the cold weather alternative?

As to the corn being inexpensive, that was my question.  Is (or was) it inexpensive because it's genuinely cheaper or because of all the subsidies etc?  When you take this into account would Beets be better, at least some significant amount of the time?

KENAT, probably the least qualified checker you'll ever meet...

RE: What about Ethanol?

I am quite sure I understand the difference between ethanol and hydrogen.


People have been making ethanol for millenia- it's the definition of a "mature technology".  Order of magnitude improvements in the energetics of this technology are unlikely.

Ethanol has not been made as a fuel for millenia, unless your talking about fueling frat parties.  Cellulosic ethanol, yeast alternatives, and improved efficiency in distillation all represent areas where order of magnitude improvements are potential.


Ethanol works just fine in ordinary internal combustion vehicles as long as you add at least a little petroleum gasoline.

My car will run on E20, but I'd never dump E85 in.  There is a reason cars need to be designed for E85.  The modifications are minor, but there are modifications required.  Furthermore, if you eliminate the requirement for flexible fueling, which could only be accomplished if sufficient numbers of fueling stations were available, ethanol only engines could acheive significantly higher efficiency by running at higher compression suited to the higher octane of the fuel.

RE: What about Ethanol?

YoungTurk said:  "Cellulosic ethanol, yeast alternatives, and improved efficiency in distillation all represent areas where order of magnitude improvements are potential."

My opinion about cellulosic ethanol is on the record here, and supported by the absence of any commercial cellulosic ethanol plant to date despite 40-50 years of development effort.

The underlying thermodynamics of the separation processes are well known and preclude order-of-magnitude improvements in the dehydration of a fermentation broth.

Ethanol, biodiesel and hydrogen have all been used by politiicans ot justify a politically expedient fairy tale:  that one day we'll invent a consequence-free alternative to gasoline which will permit the automotive status quo to continue.  And there are too many engineers and businesspeople willing to sell that particular brand of snake oil.  While the fairy tale continues to be believed, no real progress is possible.  We need to get real, and quick.

RE: What about Ethanol?

People tried to fly for hundreds of years.  The argument that flight was impossible was supported by no flight despite hundreds of years of developement effort!  (By the way, SunOpta built the first cellulosic ethanol plant 20 years ago, in France.) I believe that within five years we'll see whether ethanol can make a difference.  

Ten years ago there were no ethanol plants and no retail ethanol outlets in my area.  Today there is a plant down the road and many E85/E20/E10 stations along my commute.  

Real funding for cellulosic ethanol research dried up after oil prices dropped in the seventies.  Funding has only recently returned to similar levels.  Also, look at advances in biotechnology.  This type of tech wasn't available until the last 5 years, and it will continue to change the game. How long before someone engineers an organism or enzyme which can double the rate or concentration of conversion?

I don't disagree that there are people willing to wave energy red herrings to maintain the status quo.  I also believe there are people willing to decry ethanol, to maintain the gasoline status quo.

RE: What about Ethanol?

To me ethanol is something like a a non-realistic silver bullet, like wind, solar, and mass transportation. It has some good points and some bad. And tax credits may be what is needed to encurage development, but don't expect that in 2 weeks it will solve the oil problem.

The real point I see is that our leaders don't understand the the techinical issues. And we as engineers need to look at teaching them, or better replacing them with more intellegent people (statesmen).

The driveing factor here is and will be the cost of energy in what ever form, or the paying off of our leaders.

RE: What about Ethanol?

YoungTurk:  don't misunderstand me:  I have no interest in maintaining the "gasoline status quo"- any review of my posts to threads on this forum will show you what I think of fossil fuels.  I just consider going after gasoline and other transportation fuels to be the technological equivalent of tilting at windmills- it's technological idiocy and a dangerous distraction from the real work that needs to be done.  It permits false hope to be maintained which prevents action we could take NOW.  

It doesn't take an engineer:  any monkey can tell you that you go after the low-hanging fruit FIRST, and when it comes to fossil fuels replacement with renewables, transport ISN'T the low hanging fruit:  stationary users of fossil fuel energy are far easier to tackle.  That we aren't making real and rapid progress tackling these stationary users, while gasoline alternatives continue to be over-hyped, speaks volumes about how bad our public policy is in relation to energy production and global warming.  It's as if the only engineers involved in the setting of this policy were the ones selling the snake oil.

Like hydrogen and PEM fuelcells, there's more fundamentally wrong with ethanol as a transport fuel than can be overcome by mere wishful thinking or investment money.  As fossil fuel costs (inevitably) increase, we WILL see more of it especially if the agricultural subsidies are maintained- even corn ethanol- because it IS modestly fossil fuel replacement positive.  It's not truly renewable because of the intensive agriculture, but that's a problem for another generation.  But the basic energetics still prove that it will never replace the amount of gasoline we're using currently, nor should it.  And the limitations are thermodynamic ones:  you can't invent your way out of them I'm afraid.

A carbon tax or a carbon dioxide cap and trade system, properly implemented, will help to ensure that the solutions we choose for ALL energetic and climate change problems are at least no dumber than the ones we're trying to replace.  That is, if the subsidies on the alternatives like ethanol similarly dissapear:  until they do, the market is distorted and the results may not be in our best interest.  We should NEVER subsidize consumption as what we really want to do is to to reward conservation.  If the tax ensures that it costs too much in fuel to transport the corn stover or switchgrass to the cellulose ethanol plant, or the corn ethanol brewer's mash plus ethanol fuel product doesn't pay for the energy to dehydrate the ethanol, there will be no economic incentive to do it.

By the way, it would appear that my statement that there is, as of yet, still NO commercial cellulosic ethanol plant operating in the world, remains accurate.  There have been PLENTY of demo plants.  The SunOpta site talks about the wheat straw to ethanol plant in Spain as being, "when completed", the first commercial plant- and that depends on your definition of commercial of course.

RE: What about Ethanol?

Why must every solution to a problem be best implemented with a Tax?

Perhaps we should instead limit the KWH each home may receive.

If you wish to have a larger home, then it is on you to provide a 100 percent renewable source of power.

Perhaps we could stop subsidizing the flight costs of the Airlines, who delight in burning fossil fuels to fly people to Las Vegas for 49 dollars.

I do not have all the answers, but as an Engineer, it seems equally foolhardy to think that taxation is any more a real, long term solution than the use of Corn Ethanol is.

It would sure give the Government more money to waste though.

RE: What about Ethanol?

Popular Mechanics has an interesting article on the topic in February's edition that I recommend to everyone.

The real problem is not with ethanol, hydrogen or any other option. It is that politicians (and their friends with deep pockets)are dictating our direction of growth. As fuel prices increase I believe the market, supported by diverse research, will find better alternatives. I don't think dictating mandatory levels of ethanol production really helps anything. The future of our economy and way of life depends on finding a sustainable and affordable source of energy. Politicians can only see through the next election. Do we really want them controlling the welfare of future generations?

RE: What about Ethanol?

Ah, rationing.

I've brought up the idea before in previous threads, never got much response.

I think I saw an article about CO2 rationing being considered by Blair sometime last year.

Every citizen gets a carbon allowance.

Not sure what happened if you went over it, if you didn't get any more, had to pay some kind of surcharge/tax or if you just relied on carbon trading to buy someone elses allowance.

All of these have issues, and as we're not all even convinced on the whole climate change issue it's causes effects etc then I doubt if many here would support it.

(oops, just noticed Don P brought up Brazil using beets, sure he meant cane, so I did miss something sad)

KENAT, probably the least qualified checker you'll ever meet...

RE: What about Ethanol?

Well, I believe the OP was about whether there were benefits to ethanol over gasoline.  And on that topic alone, I answer in the affirmative.

I'm not about to disagree that there are other places we need to focus our efforts.  I don't believe taxes or cap and trade legislation are the answers.  Conservation is not a viable solution, out society needs energy to continue to evolve.  Efficiency is key, the energy is out there, solar, biological, nuclear, etc.  

"Inventing" our way to sustainable energy is the only way to fuel our vehicles, our homes, our economy, and our society into the future.

RE: What about Ethanol?

Why must the best answer to every problem involve a tax, patdaly?  Because the current economy assigns a zero cost to dumping sh*t into the atmosphere that we all must breathe, or die.  So guess what- technologies that dump bad things into the atmosphere are economically favoured.

The only way to fix that is with a tax.  Or with another system which assigns a cost to dumping bad things into the atmosphere such as a cap & trade system.  Since the latter only really works for major emitters and is hidden from CONSUMERS, the people who really need their habits changed, the tax is far more likely to work.

Try to fix problems like global warming, or the US dependence on foreign oil, by voluntary measures alone or by regulation alone, and you're fighting the market- and the result is entirely predictable.

We won't invent our way out of this problem unless there's an economic driving force to do it.  Create the driving force and the invention is likely to follow.  Subsidizing consumption by blessing ethanol as a "virtuous" fuel is wrong-headed, as no energy source is free of environmental consequence.

RE: What about Ethanol?

The other reason that a tax is necessary is that the cost to an oil seller, of that sale, is small, relative to the inherent value of the oil (I assume you would agree that oil is worth more than bottled water as a resource for future generations?). Therefore it is in the oil suppliers best short term interests to sell as much oil as he can. In a free market there is no way to compensate for this, so you either restrict production via a cartel, and/or tax it.


Greg Locock

Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.

RE: What about Ethanol?

I'm not voting for either of you tax and burn environmental liberals!

An interesting story from the NYT on a GM investment in an ethanol company:



Mary Beth Stanek, G.M.’s director for energy and environment, said the process showed “near-term readiness” and that no scientific work was involved to commercialize it.

So, given the pessimistic tone of most posts here, have at it; what is the catch/problem with this technology?

RE: What about Ethanol?

The catch/problem is scale.  Pumping crude from a well is quite a bit faster than fermenting sugar beet.

- Steve

RE: What about Ethanol?

Dried distillers grains and dried distillers grains solubles are only dried before entering the food process for animals.  The protein percentage is tripled because the starch is almost totally used in fermentation.  Over 3 million tons of DDG & DDGS are produced and fed to animals.

RE: What about Ethanol?

I hate taxes like everyone else.  But we are trained on a reward system from birth.  I do my homework, I get a a new game.  I work hard, I get a giant SUV, I deserve it.  They only thing we know is rewards for acting certain ways. Our past generations had the same thing, EXCEPT, satisfaction was a reward.

To break this reward must be a physical thing we have to strat re-training, but that take generations and we do not have generations.  The only recourse is via physical limits or taxes on bad things.  Look, we have sin taxes, it works.  

As for ethanol from the OP, when surplus corn is sent to the fuel market, its OK, but even with coproducts and other social-eco impacts it is not correct.  The E85 car is a sham to the public as it takes absolutely no upgrade from ethanol in its use.  The E85 cars go against all engineering principles of fitness for use.

RE: What about Ethanol?

Soo...the answer is to raise taxes on oil imports...then spend that extra money on what?  Hydrogen wells?  Solar powered cars?  Bicycles?

At least ethanol is a (potentially) renewable, energy-dense liquid fuel that we can use with current-technology motors to continue to transport people/things.  Name your substitute for this?

RE: What about Ethanol?

btrue, alternatives to ethanol which more or less meet your definition:

butanol http://www.technologyreview.com/Energy/18443/

Biodiesel http://en.wikipedia.org/wiki/Biodiesel (heard an article on radio the other day that the EU is re-considering it's possition on this)

Methanol http://en.wikipedia.org/wiki/Methanol_fuel

So there's a few for you.

Not quite a direct replacement but I did see this the other day which is perhaps a move to more practical electric vehicles http://www.msnbc.msn.com/id/22240865/

KENAT, probably the least qualified checker you'll ever meet...

RE: What about Ethanol?

My understanding is that some ethanol plants now delever wet processed grain to cattle feed yards, thus saving the cost of drying the mash.

I have no problems with biodiesel, but it can become in direct conflect for farm land with ethanol. Also, if I recall, in some biodiesel processes they use ethanol.

Have you heard that they can use lard, and beef fat to make biodiesel. Will sort of lower the cost of meat.

Looking at the cost of E85 cars, it will probally be several years before I purchase one.

RE: What about Ethanol?

If you want to gasify biomass to make syngas like GM's Coskata is doing, there's a heck of a lot better uses to put that syngas to than into making ethanol by fermentation!

Doesn't matter if you're fermenting starch or fermenting syngas:  you still get a water solution of ethanol that you have to dehydrate!

Conventional ethanol plants aren't burning corn stover to make the steam to run the stills- they're using natural gas.  Doesn't that tell you something?  COULD they burn corn stover, with or without bothering to gasify it first?  Certainly they could, but they choose not to for good reasons!

Are the fertilizer plants gasifying biomass to make the hydrogen to make fertilizer from?  Nope- they're using natural gas too...

TAX THE FOSSIL CARBON and the market will sort it out.  Until that happens, the technological/economic/governmental wierdness is guaranteed to continue.

Why is GM investing in Coskata?  Because people are starting to see the writing on the wall:  gasoline consumption has to decrease.  Given the business they're in, they'd rather you held out a (false) hope of having gasoline replaced with agricultural-sourced ethanol than by reducing the number and size of cars on the roads!

RE: What about Ethanol?

Costaka is touting a membrane seperation technology.  Membrane seperation technology is much more efficient than simple thermo dehydration.  Sure, they could burn the syngas in generator turbines, but there are many sources of fuel for stationary energy production.  The options for transportation fuel are much more limited.


gasoline consumption has to decrease.

How do you get to work?  How do you visit your family?  In my neck of the woods things tend to get spread out, we've got to get from point A to point B.  Ethanol is the only tech I'm aware of with a shot in hell of doing the two most important things while still getting us around: giving us a carbon friendly fuel and reducing our dependence on foreign oil.

On another topic,


Have you heard that they can use lard, and beef fat to make biodiesel. Will sort of lower the cost of meat.

I believe Switzerland is running two train lines on methane produced from meat byproducts from slaughterhouses.  I've also heard of an ethanol plant/pig farm in Iowa using methane from the pig waste for ethanol dehydration and the distillers grains for feed.  When co-located efficiencies gained are considerable.

RE: What about Ethanol?

So I guess our only salvation is to trust the same Government that is reducing the fuel mileage of our vehicles by mandating things such as zero emissions and Tire Pressure Monitoring and is subsidizing Airlines who promote flying to Vegas for the weekend to tax us into submission?

Sorry, the cynic in me sees the folly of taxation.

RE: What about Ethanol?

What happened to the ethanol plant in Nebraska that was to run on coal?

RE: What about Ethanol?

patdaly:  I greatly prefer taxation to regulation.  Regulations get subverted by lobbying too easily.

Attempting to regulate fuel economy in vehicles is foolhardy because it doesn't deal with the market pressures which underly the choice of vehicle in the first place.  People care insufficiently about fuel economy even now because, fundamentally, fuel is FAR too cheap.  Subsidizing ANY fuel, or any fuel user, is bad public policy.

I prefer either (regulation or taxation) to doing NOTHING about a known problem with the market:  the fact that dumping bad things into the atmosphere is not assigned a cost to those doing the dumping, but does represent a whole series of costs to all of us.  All fuels have environmental consequences.  

YoungTurk:  membranes, absorption or distillation, the fundamental thermodynamic limitations are the same.  Ethanol likes water a lot- and engines don't.  Hydrogen bonds are pretty strong.  Yes, membrane or mol sieve dehydration can be less energy intensive than extractive distillation to break the azeotrope, but the molecules don't just jump across the membranes or jump back off the mol sieves of their own accord- you're still climbing the same entropic gradient at the end of the day.

If you've got syngas as your starting point, you can make methanol without worrying about the bugs or the water.  Existing technology, used since the '60s.  You can also make FT wax which you can crack to make diesel (that one has been done since the '30s).  You can also simply burn it, or burn the fuel directly without bothering with the lossy, expensive syngas generation step if what you're after at the end of the day is heat.  And while 60+% of our energy needs are stationary and largely still supplied from fossil sources, going after transportation fuels remains foolhardy.

Tax the carbon appropriately and the market will sort it out.  Government can put the tax revenue in a pile and burn it and it will still work.

Kicking our gasoline addiction won't be easy, but it will be impossible while people continue to feed the false hope that there's a magical technological fix out there.

RE: What about Ethanol?

There are solutions to most of our stationary energy needs, except the there are these people in the way. (Maybe we should burn people?)
The issue is the polution generated by the least effecient energy usage, transportation. And I don't see a clear solution to the oil problem.
Drill more, yes that works, except there are these people in the way.
Ethonol, yes it helps, and it helps the oil burn better.
Electric, maybe for short distances.
Propane, Where do you fill it up?
Hydrogen, it's not a complete fuel, it needs a source.

If taxes is to help, try taxing tires, they seem to measure distance traveled better than oil taxes. And besides tires are a desposel problem also.

RE: What about Ethanol?

Perhaps instead of regulating or taxing, we could let the free market regulate the situation?

As oil becomes more expensive, without artificial manipulation via. regulation or taxation, we will find the next technology.

Sorry to say, this is one of those threads that cannot be solved, much as any political or religious issue.

Thanks for listening, I'm out of this hand boys.

RE: What about Ethanol?

Kenat, butanol is more expensive to make (right now) than ethanol, methanol is still corrosive to car parts I thought, and biodiesel works in something like <10% of existing engines.  But okay, the real question is, why discard biofuels, they have the possibility of replacing imported oil and the benefit of being a lower carbon footprint.

Molten, ok, ok.  Tax oil and coal?  Are you ready to pay triple for your domestically produced steel, do you tax steel imports to make sure foreign producers don't get away with not paying the carbon tax on their coke pile?  How far down the processing stream do we go with that, tax all raw plastic imports, tax toys, do we tax chewing gum with its petrol-derived flavor enhancers.  A globally-agreed-to carbon tax might work, thought we would see that as an outcome from Kyoto, but we got instead "US must stop driving cars so that the 3rd world can catch up".

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