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Ethanol Fuel from Corn Faulted as ‘Unsustainable Subsidized Food Burning’

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scott1
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Feb19-06, 01:01 PM
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David Pimental, a leading Cornell University agricultural expert, has calculated that powering the average U.S. automobile for one year on ethanol (blended with gasoline) derived from corn would require 11 acres of farmland, the same space needed to grow a year's supply of food for seven people. Adding up the energy costs of corn production and its conversion into ethanol, 131,000 BTUs are needed to make one gallon of ethanol. One gallon of ethanol has an energy value of only 77,000 BTUS. Thus, 70 percent more energy is required to produce ethanol than the energy that actually is in it. Every time you make one gallon of ethanol, there is a net energy loss of 54,000 BTUs
http://healthandenergy.com/ethanol.htm
I thought it was soppsed to be cheaper What ever happend to Hydorgen fuel cells powerd cars.
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russ_watters
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Feb19-06, 02:24 PM
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Cheaper and more efficient are not always the same thing. Those numbers do surprise me though.

Anyway, whether that is a bad thing or not depends on what the goal is: if the goal is simply getting off the foreign oil dependency, then cornahol can help do that. But the extra energy needed to manufacture it still needs to come from somewhere - and today that means either coal or nuclear power. The same issue exists for fuel cells (unless the hydrogen is manufactured from methane) - they are a net-loss of energy process as well because of the energy required to manufacture the hydrogen.

Fuel cell cars are still on the horizon, but the horizon is just pretty far away. Since to me the pollution issue is the larger issue (and nuclear->hydrogen fixes both problems), I don't see cornahol as being a big help - it is still a hydrocarbon and still pollutes.
baywax
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Jul6-08, 02:30 PM
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Quote Quote by russ_watters View Post
Cheaper and more efficient are not always the same thing. Those numbers do surprise me though.

Anyway, whether that is a bad thing or not depends on what the goal is: if the goal is simply getting off the foreign oil dependency, then cornahol can help do that. But the extra energy needed to manufacture it still needs to come from somewhere - and today that means either coal or nuclear power. The same issue exists for fuel cells (unless the hydrogen is manufactured from methane) - they are a net-loss of energy process as well because of the energy required to manufacture the hydrogen.

Fuel cell cars are still on the horizon, but the horizon is just pretty far away. Since to me the pollution issue is the larger issue (and nuclear->hydrogen fixes both problems), I don't see cornahol as being a big help - it is still a hydrocarbon and still pollutes.
Russ, how far away do you see nuclear cars happening?

Ivan Seeking
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Jul6-08, 03:11 PM
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Ethanol Fuel from Corn Faulted as ‘Unsustainable Subsidized Food Burning’

Quote Quote by scott1 View Post
http://healthandenergy.com/ethanol.htm
I thought it was soppsed to be cheaper What ever happend to Hydorgen fuel cells powerd cars.
Yes, it is well known that ethanol is a failed option and extremely inefficient. Whether ethanol is a net loser, or if we get a slight energy advantage from it, is hotly debated. But either way it is not a practical option.

Also, it takes not only electrical power to make ethanol, it also takes lots of diesel fuel.

We are light-years away from cost effective fuel cells. In order to buy a fuel cell today off-the-shelf, that would provide the same power that a small car engine does, it would cost something close to 1/2 million dollars. And then you still have to provide fuel. Something else not mentioned is that gasoline has something like 125,000 BTUs of energy per gallon. So in addition to the inefficiency of making ethanol, we get far less energy back per gallon than we do from gasoline or diesel.

Here are more related discussions.

http://www.physicsforums.com/showthread.php?t=227505
http://www.physicsforums.com/showthread.php?t=211274
http://www.physicsforums.com/showthread.php?t=242546
http://www.physicsforums.com/showthread.php?t=241122
http://www.physicsforums.com/showthread.php?t=171576
Averagesupernova
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Jul6-08, 03:37 PM
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How are they arriving at the amount of energy put into a gallon of ethanol? Are they considering that there are biproducts from the ethanol process that are still valuable? How do you subtract the amount of energy used to produce what is left after the carbohydrate is removed from the corn to make ethanol? It took energy to produce the protiens in the first place that are left over after ethanol extraction. I won't argue that ethanol is a fix-all because quite simply it is not.
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As for the 'subsidized food burning'? Fuel competes with food no matter what the fuel as long as we utilize it to produce crops and food. Until someone comes up with a fuel that can only be used to power the equipment used to produce the crops/food and nothing else, then fuel will compete with food. Fuel/cost hungry crops will not be grown until it is profitable, or any crop for that matter. In order for it to be profitable to grow these kinds of crops then the market price for them will have to be high. The reality is that fuel and food are already in competition.
Ivan Seeking
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Jul6-08, 04:38 PM
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Quote Quote by Averagesupernova View Post
How are they arriving at the amount of energy put into a gallon of ethanol? Are they considering that there are biproducts from the ethanol process that are still valuable? How do you subtract the amount of energy used to produce what is left after the carbohydrate is removed from the corn to make ethanol? It took energy to produce the protiens in the first place that are left over after ethanol extraction. I won't argue that ethanol is a fix-all because quite simply it is not.
What byproduct is produced making ethanol that would otherwise require the same, or nearly the same amount of energy?

As for the 'subsidized food burning'? Fuel competes with food no matter what the fuel as long as we utilize it to produce crops and food. Until someone comes up with a fuel that can only be used to power the equipment used to produce the crops/food and nothing else, then fuel will compete with food. Fuel/cost hungry crops will not be grown until it is profitable, or any crop for that matter. In order for it to be profitable to grow these kinds of crops then the market price for them will have to be high. The reality is that fuel and food are already in competition.
See the discussions linked above.
Averagesupernova
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Jul6-08, 11:35 PM
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Quote Quote by Ivan Seeking View Post
What byproduct is produced making ethanol that would otherwise require the same, or nearly the same amount of energy?
Distillers grain is the byproduct. The only thing that ethanol takes out of corn is carbohydrates. Distillers grain is a high source or protien. So my question to you is this: Should we continue to grow corn the same way we did before the ethanol boom and not get any energy out of it besides feed? Carbohydrates is not necessarily a desirable part of feed. Doing that guarantees no energy return with a significant amount of energy expended to produce the crop. Ethanol plants are coming on-line that produce ethanol with no external energy input. Simplified this means that they are burning part of what they produce to produce more. Same thing the petroleum refineries do.


Quote Quote by Ivan Seeking View Post
See the discussions linked above.
Ivan I'm not sure what you mean by bringing up these links again. I fail to see the relevance. I've read through them already and skimmed again. I think you are assuming I have beliefs that I do not. I know about the claims of algae and etc. That is not the point. My point is that until food is grown by using a fuel that NOTHING ELSE USES EVER, then food and fuel will be in competition. Obviously that will never happen so food and fuel are just about guaranteed to be in competition. Ethanol is not a fix-all. But it deserves more credit than it gets.
mheslep
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Jul7-08, 12:26 AM
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Quote Quote by Ivan Seeking View Post
...We are light-years away from cost effective fuel cells. In order to buy a fuel cell today off-the-shelf, that would provide the same power that a small car engine does, it would cost something close to 1/2 million dollars.
???
Thats a high estimate. Its more like $1k/kW now as has been discussed on PF. Cost per kW is not the big reach on fuel cells.
http://www.physicsforums.com/showpos...8&postcount=16
Durability and lifetime of fuel cells is still an issue. The big 'light years' away problem is the storage and production of the fuel (H)
Ivan Seeking
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Jul7-08, 01:49 AM
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Quote Quote by mheslep View Post
???
Thats a high estimate. Its more like $1k/kW now as has been discussed on PF. Cost per kW is not the big reach on fuel cells.
http://www.physicsforums.com/showpos...8&postcount=16
That is a new industrial application. I have seen nothing to indicate that this could work in an automobile. I was going by real prices, off-the-shelf.

Here
http://fuelcellstore.com/en/pc/viewP...idproduct=1107

We get 100 watts for $1600. That comes out to $16,000 per Kw.

Durability and lifetime of fuel cells is still an issue.
But even if we take your example at $1K per KW, we are still talking about $75,000 for 100 HP, which is the energy output from a small car engine. We are light-years away. It will make sense to burn hydrogen in combustion before it will make sense to use H2 fuel cells.

You need to let go of the idea that people can spend $50K-$75K for the equivalent of a gas tank. And that IS what we are talking about here; an empty gas tank. The same part of a standard auto costs a few hundred dollars.

Same goes for the Tesla car: It is nothing more than a novelty for rich kids. It is practical for nothing.
Ivan Seeking
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Jul7-08, 01:56 AM
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Quote Quote by Averagesupernova View Post
Distillers grain is the byproduct. The only thing that ethanol takes out of corn is carbohydrates. Distillers grain is a high source or protien. So my question to you is this: Should we continue to grow corn the same way we did before the ethanol boom and not get any energy out of it besides feed?
We can't get the feed without removing the carbohydrates? Just because we have a byproduct, we are still spending the energy to make ethanol unnecessarily.

Ethanol plants are coming on-line that produce ethanol with no external energy input.
Where?

Ivan I'm not sure what you mean by bringing up these links again. I fail to see the relevance. I've read through them already and skimmed again. I think you are assuming I have beliefs that I do not. I know about the claims of algae and etc. That is not the point. My point is that until food is grown by using a fuel that NOTHING ELSE USES EVER, then food and fuel will be in competition. Obviously that will never happen so food and fuel are just about guaranteed to be in competition. Ethanol is not a fix-all. But it deserves more credit than it gets.
You don't understand the difference between making fuel with fuel, and making food with fuel? The point is trivial: Every acre of corn used for fuel is an acre of corn [or other crops] for food that we don't have.
mheslep
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Jul7-08, 07:14 AM
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Quote Quote by Ivan Seeking View Post
That is a new industrial application. I have seen nothing to indicate that this could work in an automobile. I was going by real prices, off-the-shelf.

Here
http://fuelcellstore.com/en/pc/viewP...idproduct=1107

We get 100 watts for $1600. That comes out to $16,000 per Kw.


But even if we take your example at $1K per KW, we are still talking about $75,000 for 100 HP, which is the energy output from a small car engine.
Again we've been through all this before. You dont size the fuel cell to the max HP of the vehicle, you match it only to the _average_ HP required (30HP), and reach max with a buffer like batteries.

Fuel cell store is a hobby shop.
Averagesupernova
#12
Jul7-08, 01:23 PM
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Quote Quote by Ivan Seeking View Post
We can't get the feed without removing the carbohydrates? Just because we have a byproduct, we are still spending the energy to make ethanol unnecessarily.
No one said anything about not being able to get the feed without making alcohol. You have it backwards. We can STILL get the feed after taking out ethanol with a net energy gain on the ethanol starting at the time the corn hits the distillery. You HAVE to figure it this way since we are growing corn for other purposes than ethanol, which is my whole point.

Quote Quote by Ivan Seeking View Post
Where?
http://iowafarmertoday.com/articles/...th-methane.txt
Read the article. Several processes already being done are being combined to produce ethanol with no external fuel input.

Quote Quote by Ivan Seeking View Post
You don't understand the difference between making fuel with fuel, and making food with fuel? The point is trivial: Every acre of corn used for fuel is an acre of corn [or other crops] for food that we don't have.
Well if you are whining about using farmland to produce things other than food you better step back alot farther than ethanol. Soybeans are a very common crop and are utilized for plenty of things that have nothing to do with food. The bottom line is this: Everything in one way or another competes with everything else including investors driving up the price of farmland which in turn which raises the cost of production. The list goes on and on and on. As long as we have capitalism in this country with the amount of regulation that we have now this is the way it will be. I know, I know, people are starving and we here in the good old USA are making fuel out of food. If we take away the ethanol tarriffs and start importing it, someone somewhere else where it is much cheaper to produce it will be shipping it to us here in the USA and taking food away from those same starving people that we supposedly are starving by growing fuel. And what is really messed up about the whole thing is that it will most likely be an American company across the pond that is capitalizing on it with cheap labor.

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Edit: I'm done here. If you don't get my point by now you never will. I know you have your thing with algae and that is irrelevant to this discussion. I certainly won't say algae is not considerable, this is not the case.
baywax
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Jul7-08, 05:26 PM
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What's worse is we could be depriving people of air if the Air Car goes into mass-production.

Try 1000 miles on two tanks of compressed and re-compressed air.

http://www.popularmechanics.com/auto...html?series=19


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