Ethanol Deception - Is It Really Better Than Gasoline?

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A recent CNN review discussed claims from Consumer Reports that cars using ethanol do not experience decreased mileage or performance, though the source of this information was not cited. Ethanol contains significantly fewer BTUs per gallon compared to gasoline, raising questions about its efficiency and performance. Critics argue that Consumer Reports may not provide reliable data, citing past inaccuracies and suggesting that consumer satisfaction does not equate to actual performance metrics. The discussion also highlights the economic implications of ethanol production, including rising corn prices and potential impacts on food costs. Overall, the debate centers on the validity of ethanol as a viable alternative fuel and its actual performance compared to gasoline.
  • #51
Ivan Seeking said:
First, in spite of prior objections, I maintain that energy is a perfectly good way to compare fuels as long as the efficiency is known for each application. After all, in the end, sooner or later, we have to talk about the work done. This is ultimately what we have to compare. And the increased efficiency wrt ethanol in high compression engines does not apply to what we are actually driving, which was my point of reference. The CS/CNN report showed a 27% decrease in mileage in going from gasoline to ethanol, and if we take the ratio of the energy content of each as 125,000 and 76,000 BTUs per gallon respectively (76/125), we might expect about a 39% decrease, which isn't too bad as a ball park estimate given no other specifics. And of course we find significant differences in the raw energy estimates as well as differences in the fuel quality at the pump that could account for this, in addition to any efficiency variances between fuels. Not to mention that the test may have had a large margin of error.

A small correction: Since they were using E85 and not pure ethanol, considering just the reduced energy density we would expect to see about a 33% decrease in the mileage, which is getting very close to the 27% measured.
 
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  • #52
Ivan I'm NOT the one forgetting that we need the corn grown today, that's my whole point. It WILL BE GROWN REGARDLESS OF WHETHER WE TAKE ALCOHOL OUT. You seem to skip over the fact that the only thing taking the alcohol out does is remove the sugars from the corn. It is still quite useful after. I am not favoring ethanol over biodiesel at all. You speak of basic economics. Well here's some food for thought: Right now a corn/soybean crop rotation is fairly common. As there is more demand for corn more of these acres are switched over from soybeans to corn. We now raise corn on the same ground year after year on more acres than previously. This naturally affects the market price of soybeans and some other crops as there are less grown. The same thing will happen if the demand for ethanol goes down and the demand for biodiesel goes up. It will be more profitable to raise soybeans and other biodiesel crops so there will be less corn grown and this shortage will raise the price of corn. Take a look at the market price for both corn and soybeans over the last few years and you will find that they track each other.
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If you don't want fuel to directly compete with food then keep energy production out of agriculture and find some other source for it.
 
  • #53
Averagesupernova said:
Ivan I'm NOT the one forgetting that we need the corn grown today, that's my whole point. It WILL BE GROWN REGARDLESS OF WHETHER WE TAKE ALCOHOL OUT. You seem to skip over the fact that the only thing taking the alcohol out does is remove the sugars from the corn. It is still quite useful after.

Sure, it can be used for some applications, but what about those that need the corn intact? The fact is that we can't process all of the corn for ethanol which is already needed for other uses, but perhaps some could be.

I am not favoring ethanol over biodiesel at all.

I also want to be clear that I am not against ethanol because of biodiesel, rather, I became a biodiesel fan on its own merits, and have been very disappointed to learn about the reality of ethanol which I once saw as a promising option to petro.

You speak of basic economics. Well here's some food for thought: Right now a corn/soybean crop rotation is fairly common. As there is more demand for corn more of these acres are switched over from soybeans to corn. We now raise corn on the same ground year after year on more acres than previously. This naturally affects the market price of soybeans and some other crops as there are less grown. The same thing will happen if the demand for ethanol goes down and the demand for biodiesel goes up. It will be more profitable to raise soybeans and other biodiesel crops so there will be less corn grown and this shortage will raise the price of corn. Take a look at the market price for both corn and soybeans over the last few years and you will find that they track each other.

Absolutely a valid point. Parts of the solution are the other crops like cotton, canola etc which helps to spread out the pain, but...
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If you don't want fuel to directly compete with food then keep energy production out of agriculture and find some other source for it.

I see it like this: Biodiesel is superior to ethanol in many ways, not the least of which are: The diversified base of feedstock; 1.5 times the energy density; a more efficient [as a percent of yield] processing chain. Now, if we didn't have algae as a real option today, biodiesel would have the same problem as ethanol in that we couldn't possibly grow enough. But we do have the algae option, and macro plants are available today to help with the short term demand for biodiesel. In turn, biodiesel is the carrot to go diesel. So we go diesel, then biodiesel from all crops, then we begin to supplement the macro crops with algae until eventually it could supply the majority of the feedstock [of course, in reality these are concurrent events]. And most important of all, unlike ANY other option that I have ever seen, bio from algae offers a permanent solution - and one that need not compete with food.

If it wasn't for algae, there would be NO good options ready today that could actually solve the problem. [less nuclear, which I don't see as a practical reality in an age of terrorism even if we could build the plants fast enough, which we can't.]

Also, just to avoid any confusion, algae has been a practical option for some time, but it has not been competitive due to price...until now.
 
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  • #54
Ivan where do you get the 1.5 times energy density of biodiesel compared to ethanol? How is that figured?
 
  • #55
Biodiesel has 118330 BTUs per gallon. Ethanol has 76000 BTUs per gallon. This taken with the efficiency of the engine used for each fuel is a direct measure of the work that can be done with each gallon of that fuel. [118/76 ~= 1.5.]. Of course that 1.5 times ignores the greater efficiency of diesel over combustion engines, which makes the comparion even more drastic, as is seen below.

While we are still using regular diesel - as we convert to bio - we get 139,000 BTUs per gallon in engines that are more efficient than gasoline or ethanol powered engines. It begins to help even before we convert to bio. And the diesel cars are here or coming.

Diesel engines are already high compression engines, so the comparison is valid even if we consider engines not yet available for ethanol.

The higher energy density of bio, the greater efficiency of diesel engines, and the more efficient processing for bio suggests that Bio has about a 400% energy advantage over ethanol - every four gallons of ethanol produced can move a car down the road as far as every gallon of bio produced.
 
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  • #56
Ok. That is pretty much what I expected, but not everything I want to know. How many gallons per bushel of each? And how many bushels per acre of each?
 
  • #57
Note that I have a bunch of late edits in the last post [struggling for clarity]

Most common stats cited for gross yields:
Corn yields 400 gallons of ethanol per acre-year.
Algae yeilds about 10,000 gallons of biodiesel per acre-year.

Net yields [after we pay the energy price to grow and process the fuel]:
Corn = 120 gallons per acre-year
Algae = 7000 gallons per acre-year

I just saw that BBC World News is running a story that asks the question: Should we grow food to feed the world's starving, or grow crops for fuel?
 
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  • #58
Ivan Seeking said:
Most common stats cited for gross yields:
Corn yields 400 gallons of ethanol per acre-year...

Net yields [after we pay the energy price to grow and process the fuel]:
Corn = 120 gallons per acre-year...
As I quoted earlier, according to A.E. Farrell: "Our best point estimate for average performance today is that corn ethanol reduces petroleum use by about 95% on an energetic basis...". Therefore, in order to compute "net yields" you need to be using 0.95 instead of 0.3; and then your number above for net yields would be "...Corn = 380 gallons per acre-year".
 
  • #59
What about soybeans and other biodiesel crops? Also, what is figured in for inputs to the crop? On a corn/soybean rotation it is common to not use fertilizer at all for the soybeans. Plant food is derived from the residue of the previous years crop as well as some of the fertilizer applied for the corn crop. I guarantee you that soybeans on the same ground year after year will require some kind of fertilizer. I know next to nothing about algae but I have a very hard time believing that all it requires is air and sunlight. There must be other input to net the amount of biodiesel we are talking about.
 
  • #60
Averagesupernova said:
What about soybeans and other biodiesel crops? Also, what is figured in for inputs to the crop?
The EBAMM model (ERG Biofuel Analysis Meta-Model) provides a thorough analysis of all inputs, including the agricultural phase, of ethanol production. I don't know if they provide similar information on biodiesel.

http://rael.berkeley.edu/EBAMM/.
 
  • #61
Aether said:
As I quoted earlier, according to A.E. Farrell: "Our best point estimate for average performance today is that corn ethanol reduces petroleum use by about 95% on an energetic basis...". Therefore, in order to compute "net yields" you need to be using 0.95 instead of 0.3; and then your number above for net yields would be "...Corn = 380 gallons per acre-year".

This has nothing to do with it. We measure the yield and look at how much energy it took to produce that yield. The multiplier is ~0.3 for net yield...and based on the technology in use, that is a best case.
 
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  • #62
Ivan Seeking said:
This has nothing to do with it. We measure the yield and look at how much energy it took to produce that yield. The multiplier is ~0.3 for net yield...and based on the technology in use, that is a best case.
The multiplier is ~0.3 for net energy, but it is 0.95 for farm land. Ethanol plants use coal and natural gas as energy inputs which accounts for the difference. If these plants had to use all ethanol or petroleum as their only energy inputs then the number for farm land would be ~0.3; but they do not have to do that, nor do they choose to do that in practice.
 
  • #63
Averagesupernova said:
What about soybeans and other biodiesel crops? Also, what is figured in for inputs to the crop? On a corn/soybean rotation it is common to not use fertilizer at all for the soybeans. Plant food is derived from the residue of the previous years crop as well as some of the fertilizer applied for the corn crop. I guarantee you that soybeans on the same ground year after year will require some kind of fertilizer. I know next to nothing about algae but I have a very hard time believing that all it requires is air and sunlight. There must be other input to net the amount of biodiesel we are talking about.

Some crops are much better than others, and the amount of fertilizer needed is a critical part of the energy calculation no matter what crop we use. I don't know the specifics of soybeans but it is one of the best options after algae. I'm sure that plenty of information is found with a search as soybean is a major crop used today for biodiesel.

Nitrogen and other nutrients are needed for the algae. This was all considered in the aquatic species program and later research.

One nice thing about algae is that given the proper selection of algae strains, it can survive and even thrive in highly contaminated water. This is why it can be used to clean-up industrial, ag, and municipal waste. What is considered pollution can grow algae at tremendously high rates.

Another part of what makes algae so competitive is the percent yield as a function of oil by weight. There is one strain that has been measured as having as much as 86% oil by weight. Typical yields range between 30 and 50% oil by weight [oil weight compared to weight of dry algae before processing]. And it isn't that hard to understand when you think about it. Algae is a very simply organism that only does a few things. It is also very small - often in the range of about 5 to 10 microns in size - so it is very efficient in that it occupies 100% of the light incident area, and almost all of this is going towards fuel production rather than growing stalks, leaves, etc.
 
  • #64
Aether said:
The multiplier is ~0.3 for net energy, but it is 0.95 for farm land. Ethanol plants use coal and natural gas as energy inputs which accounts for the difference. If these plants had to use all ethanol or petroleum as their only energy inputs then the number for farm land would be ~0.3; but they do not have to do that, nor do they choose to do that in practice.

This is not what the multiplier means. It is a measure of total efficiency. What you are talking about is using other energy to make ethanol, and this is not a viable option as we don't have the power needed to make it. In effect, what you are saying is that we should convert to coal power. And either way, we still couldn't possibly grow enough corn.

In the case of an energy carrier, hydrogen is more efficient as it returns about 50% of the energy used to make it, not 30%. And we don't need corn, just water. Also, hydrogen can be burned in traditional engines.
 
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  • #65
Ivan Seeking said:
This is not what the multiplier means. It is a measure of total efficiency.
You are trying to use this multiplier to support your claim that farm land yields only 120 gallons of ethanol per acre-year instead of 380. This is clearly wrong.
What you are talking about is using other energy to make ethanol, and this is not a viable option as we don't have the power needed to make it. In effect, what you are saying is that we should convert to coal power.
No, what I am talking about at the moment is how many acre-years of farm land it takes to make 380 gallons of ethanol.
In the case of an energy carrier, hydrogen is more efficient as it returns about 50% of the energy used to make it, not 30%. And we don't need corn, just water.
Maybe so, but that doesn't have anything to do with how many acre-years of farm land it takes to make 380 gallons of ethanol.

Incidentally, if ethanol has 30% net energy, then that means that it returns 130% of the energy used to make it; not 30%.
 
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  • #66
If we use coal power to make ethanol, yes, it would take less land. Of course we still couldn't grow enough corn. You keep ignoring this point.

Where are we going to get the power? We don't have it, so we would have to either build a tremendous number of coal plants to produce ethanol, or use ethanol energy produced on-site to make the fuel. Either way we need to get the energy from somewhere.

When we talk about net energy returns, what we mean is how much of the available energy do we get to use. This is 30%. This is how we measure the net energy gain. You can play games all day, but the energy has to come from somewhere, and ethanol can't provide the energy, so ethanol is not an energy solution, which was the point of this thread.

Oh yes, your point about hydrogen is valid. I was using two different ways to compare. With ethanol we put in 66 BTUs and get 100, so we see a 50% gain in this sense. With hydrogen we put in 66 and get back 33 [or so].
 
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  • #67
Ivan Seeking said:
If we use coal power to make ethanol, yes, it would take less land.
Well, this is how we make ethanol today; using coal and natural gas.
Of course we still couldn't grow enough corn. You keep ignoring this point.
Maybe so, but this is a different issue. You don't mind if we discuss (and resolve) one issue at a time do you?
Where are we going to get the power? We don't have it, so we would have to either build a tremendous number of coal plants to produce ethanol, or use ethanol energy produced on-site to make the fuel. Either way we need to get the energy from somewhere.
We currently get the energy from domestic coal and natural gas; future plans are to use cellulosic ethanol where the energy comes entirely from lignin which is a part of the plants themselves.
When we talk about net energy returns, what we mean is how much of the available energy do we get to use. This is 30%. This is how we measure the net energy gain.
Wrong. If you look at the EBAMM spreadsheet you will see the detailed data from six separate published studies on the subject of the net energy of ethanol production. Here is a summary; output energy includes "coproduct credits":

Patzek: 27 MJ/L energy input vs. 25 MJ/L energy output = 93% return.
Pimentel: 26 MJ/L energy input vs. 23 MJ/L energy output = 88% return.
Shapouri: 21 MJ/L energy input vs. 29 MJ/L energy output = 138% return.
Graboski: 22 MJ/L energy input vs. 25 MJ/L energy output = 114% return.
de Oliviera: 20 MJ/L energy input vs. 25 MJ/L energy output = 125% return.
Wang: 19 MJ/L energy input vs. 25.2 MJ/L energy output = 133% return.
 
  • #68
Currently we have 600 coal plants producing a total of about 22.9 quads of energy annually. All petroleum used has about 38.8 quads of energy with a chain efficiency of about 80%. So we need about 31 quads of energy to replace petro, or 23 quads to make enough ethanol [with a 50% gain based on input power]. So, in order to produce enough ethanol using coal power, we would need about another 600 additional coal plants.

Late edits: I was assuming that we still need to allow for efficiencies already accounted for.
 
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  • #69
Aether said:
Well, this is how we make ethanol today; using coal and natural gas.Maybe so, but this is a different issue. You don't mind if we discuss (and resolve) one issue at a time do you? We currently get the energy from domestic coal and natural gas; future plans are to use cellulosic ethanol where the energy comes entirely from lignin which is a part of the plants themselves.

Future options don't count. When they are viable, then they become part of the discussion.

Wrong. If you look at the EBAMM spreadsheet you will see the detailed data from six separate published studies on the subject of the net energy of ethanol production. Here is a summary; output energy includes "coproduct credits":

Patzek: 27 MJ/L energy input vs. 25 MJ/L energy output = 93% return.
Pimentel: 26 MJ/L energy input vs. 23 MJ/L energy output = 88% return.
Shapouri: 21 MJ/L energy input vs. 29 MJ/L energy output = 138% return.
Graboski: 22 MJ/L energy input vs. 25 MJ/L energy output = 114% return.
de Oliviera: 20 MJ/L energy input vs. 25 MJ/L energy output = 125% return.
Wang: 19 MJ/L energy input vs. 25.2 MJ/L energy output = 133% return.

I will have to take some time later to look at what you have, but coproducts don't count unless we can show that first, we can use the byproducts, and next, that we would be saving energy already used today. When one considers the amount of production involved, it is extremely unlikely that we could use most of the byproducts [as a signficant percent of the total yield]. The example of glycerin from biodiesel given earlier is a perfect example. Even now, with only a trickle of biodiesel produced as a percent of total demand, the glycerin market is flooded and the price has dropped. When considering byproducts, we have to first consider the demand for that product, and then the energy used to produce that product today, otherwise the projections are meaningless and the coproduct may even end up as a liability - you will be paying to get rid of it as garbage.

The 0.3 multiplier is correct as an honest measure of the gain based on yield. You are talking about using power from other sources that don't exist.
 
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  • #70
Ivan Seeking said:
Estimates and three decades of testing indicates that by using algae, we can produce as much as a net 10,000 gallons of biodiesel per acre-year - say 7000 if we stay conservative and allow for a 30% processing demand. See the aquatic species program [in addition to plenty of more recent links found with a simple search] which predicted that algae could be competitive when diesel was at about $2 a gallon, or twice 1996 levels. [see part ii, page 4]
http://www1.eere.energy.gov/biomass/pdfs/biodiesel_from_algae.pdf

Not that we would want to, but a simple estimate suggests that we could replace all sources of energy - petro, coal, NG, hydro, nuclear, wind, solar - with about 400 X 400 miles of land and or water. In the process, algae can be grown while cleaning up CO2 or other industrial, agricultural, or municipal emissions or waste.
The report that you cited was generated in 1998 upon the close-out of the Aquatic Species Program, and here is what this agency has to say about biodiesel today:
www1.eere.energy.gov said:
Note: The Department of Energy's Office of Biomass Program has refocused its research and development portfolio and the technology on this page is no longer a research priority.
http://www1.eere.energy.gov/biomass/renewable_diesel.html

Ivan Seeking said:
Currently we have 600 coal plants producing a total of about 22.9 quads of energy annually. All petroleum used has about 38.8 quads of energy with a chain efficiency of about 80%. So we need about 31 quads of energy to replace petro, or 23 quads to make enough ethanol [with a 50% gain based on input power]. So, in order to produce enough ethanol using coal power, we would need about another 600 additional coal plants.
Biodiesel production seems to be dependent on CO2 from coal plants, and therefore it may not be practical on the scale that you envision.

Biodiesel from Algae said:
The main focus of the program, know as the Aquatic Species Program (or ASP) was the production of biodiesel from high lipid-content algae grown in ponds, utilizing waste CO2 from coal fired power plants...Algal biodiesel could easily supply several “quads” of biodiesel—substantially more than existing oilseed crops could provide. Microalgae systems use far less water than traditional oilseed crops. Land is hardly a limitation. Two hundred thousand hectares (less than 0.1% of climatically suitable land areas in the U.S.) could produce one quad of fuel.
Ivan Seeking said:
Future options don't count. When they are viable, then they become part of the discussion.
Biodiesel from Algae said:
...the technology faces many R&D hurdles before it can be practicable...
 
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  • #71
Ah, now we change the argument.

As I stated earlier, bio from algae was not competitive until we reached today's prices. At some price for fuel, it would be worth growing algae in your pool and scooping it out with a net. The CO2 requirements were to provide enough growth to be economically viable.
 
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  • #72
Ivan Seeking said:
Ah, now we change the argument.
Do you think that I am being unfair to you in some way? You acknowleded above that one acre-year of farm land is required to produce 380 gallons of ethanol if coal is also used as an input, so that issue is now resolved.

As I stated earlier, bio from algae was not competitive until we reached today's prices. At some price for fuel, it would be worth growing algae in your pool and scooping it out with a net. The CO2 requirements were to provide enough growth to be economically viable.
Okay, but I didn't see that stipulation anywhere in your argument before now. I don't doubt that you can produce a limited amount of biodiesel at a reasonable price using dense CO2 from coal plants as an input. However, this process is not scalable because there is a limited supply of dense CO2.
 
  • #73
Aether said:
Do you think that I am being unfair to you in some way? You acknowleded above that one acre-year of farm land is required to produce 380 gallons of ethanol if coal is also used as an input, so that issue is now resolved.

Sure, if we want to build 600 coal plants ethanol is viable at that rate of production. Have you figured out that your 150% is the same as my 30%?

Okay, but I didn't see that stipulation anywhere in your argument before now. I don't doubt that you can produce a limited amount of biodiesel at a reasonable price using dense CO2 from coal plants as an input. However, this process is not scalable because there is a limited supply of dense CO2.

I said early on that much of the literature focuses on making algae competitive at much lower prices, which it was not, but at today's prices the story is quite different. And just for the record, I have been getting viable yields under far less than ideal circumstances - only about 60% of the light that things should have, and no CO2 added at all, only aeration. Also keep in mind that we have lots of people working on this right now, and some estimates are as high as 20,000 gallons per acre-year - some people claim to be getting yields this high [which would only represent about a 10% conversion efficiency, same as solar cells]. But even the lowest estimates are viable at today's prices.

If I'm wrong, it will cost me dearly.
 
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  • #74
IMO, it is imperative that we select the best path available to us, and clearly bio from algae is the best option by far. Ethanol cannot solve the energy problem with technology that exists today, and I have learned to quit betting the farm on what we will be able to do in the future - the future is often not what is promised.
 
  • #75
Oh yes, one last thought and then I'm out of this one: We already have a tremendous demand for diesel from the trucking and other industries, so bio has a market before we even talk about cars. And no doubt ethanol will continue to help reduce the demand for petro for many years to come, so the corn farmers can relax for at least a decade or more.

Edit: Okay I lied, one more last thought: If one studies the algae option for a year and half as I have, it becomes apparent that some concerns mentioned earlier are not an issue. But at this point we are into proprietary information and I have to be selfish to protect my own interests.
 
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  • #76
The January 2007 issue of Scientific American had a detailed study on the viability of corn ethanol. It concluded if 100% of the U.S. corn crop was diverted to ethanol production, it would power only a small fraction of the nation's vehicles: http://www.nelson.wisc.edu/outreach/biofuels/readings/isethanolforthelonghaul.pdf

So aside from the net energy balance problem (whether it takes more energy to produce corn ethanol than the final product contains), there's simply not enough acreage at current yield rates to provide sufficient ethanol to make a significant difference. That's even if all corn food production ceased in favor of ethanol production.

Celulosic conversion in theory has higher yield and net energy efficiency, but it's unknown whether this can be done on the gigantic industrial scale required: http://en.wikipedia.org/wiki/Cellulosic_ethanol
 
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  • #77
Ethanol as fuel is a sop to ADM and others to subsidize their crop prices. I was an industrial training consultant in the 1990s and visited a plant owned by Quantum Chemicals in Iowa. The plant (IMO) would not and could not ever be self-sufficient and had to rely on US subsidies to remain in operation. The US taxpayers are being soaked by a lot of players in the alternate fuel market.
 
  • #78
joema said:
The January 2007 issue of Scientific American had a detailed study on the viability of corn ethanol. It concluded if 100% of the U.S. corn crop was diverted to ethanol production, it would power only a small fraction of the nation's vehicles: http://www.nelson.wisc.edu/outreach/biofuels/readings/isethanolforthelonghaul.pdf

So aside from the net energy balance problem (whether it takes more energy to produce corn ethanol than the final product contains), there's simply not enough acreage at current yield rates to provide sufficient ethanol to make a significant difference. That's even if all corn food production ceased in favor of ethanol production.

Celulosic conversion in theory has higher yield and net energy efficiency, but it's unknown whether this can be done on the gigantic industrial scale required: http://en.wikipedia.org/wiki/Cellulosic_ethanol

I want to thank you for introducing me to the Aquatic Species Program. Note my new avatar - you killed the alien!

I have started a new company that will produce biodiesel from algae, and things are coming along very nicely. :cool:
 
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  • #79
What is involved in the algae process? Do you need to own your own lake?? Or is the process a factory type operation? Just curious.
 
  • #81
We know very well how to produce fuel from algae, the key is to develope methods and systems to do this as cost effectively as possible. Since the cost of fuel is now high enough to justify pursuing the technology, we seem to be at the point where many people are keeping their bioreactor designs a secret - it is now a competitive industry and most people working on this won't say much. But I will say that there are thousands of strains of algae - we don't know much about many of the best candidates for fuel production - and probably several dozen critical design concepts.
 
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  • #82
A couple of questions:
Does anyone know how much energy is spent converting crude fuel to processed gasoline? What about corn, sugar beets, or algea to something that is in its final combustible form?

I'm just wondering how many alternate styles are more: "We produced 1 gas-gallon equivalent of fuel made from some high-yield crop and it only cost 2 gas-gallon equivalents from our local coal/gas power plant in energy."

I'm sure some of these methods have to be easier and more energy efficient than others to converto to a burnable fuel?



And as a side note, has hydrogen been completely removed from our thoughts? I always thought the best long-term solution was a "nuclear" powered car. Nuclear power plant's grids used for electrolysis to make hydrogen to be stored and distributed. I know they calimed for a while that the "biggest" issue was a way of storing it safely. But I remember back in college about 5-6 years ago (I went to Kettering / GMI Tech) we had a talk (I think I can talk about this...) from GM I believe, where they, or someone, had developed a way to store hydrogen in reusable carbon plates. It was basically you could reuse the material to soak in hydrogen, and then dissolve it in your drivetrain somewhere to release the gas hydrogen. I believe both the plates and the chemical used to dissolve were both reusable in some sort of way.
 
  • #83
Healey01 said:
A couple of questions:
Does anyone know how much energy is spent converting crude fuel to processed gasoline? What about corn, sugar beets, or algea to something that is in its final combustible form?

This is the fuel chain efficiency, and for petro I believe the efficiency is about 80% for gasoline. For corn ethanol the efficiency is usually cited as about 30%. I know sugar beets and cane are better but I don't know the numbers by memory. Processing of biodiesel from algae is commonly cited as about 70% efficient - for every 100 BTUs worth of fuel, about 30 BTUs was spent growing the algae and processing the fuel.

If you read the rest of this thread, you will see that we hash this out pretty well.

I'm just wondering how many alternate styles are more: "We produced 1 gas-gallon equivalent of fuel made from some high-yield crop and it only cost 2 gas-gallon equivalents from our local coal/gas power plant in energy."

Some people claim that corn ethanol has a net zero gain.

And as a side note, has hydrogen been completely removed from our thoughts? I always thought the best long-term solution was a "nuclear" powered car. Nuclear power plant's grids used for electrolysis to make hydrogen to be stored and distributed. I know they calimed for a while that the "biggest" issue was a way of storing it safely. But I remember back in college about 5-6 years ago (I went to Kettering / GMI Tech) we had a talk (I think I can talk about this...) from GM I believe, where they, or someone, had developed a way to store hydrogen in reusable carbon plates. It was basically you could reuse the material to soak in hydrogen, and then dissolve it in your drivetrain somewhere to release the gas hydrogen. I believe both the plates and the chemical used to dissolve were both reusable in some sort of way.

Hydrogen can be processed from algae, so I see biodiesel from algae as a step towards hydrogen. However, for now, and until the hydrogen from algae process is more fully developed, IMO the best solution is biodiesel.

I don't think we could build enough nuke plants to replace petro for about 200years, even if we started building them today, which we won't.
 
  • #84
Healey01 said:
...has hydrogen been completely removed from our thoughts? I always thought the best long-term solution was a "nuclear" powered car. Nuclear power plant's grids used for electrolysis to make hydrogen to be stored and distributed. I know they calimed for a while that the "biggest" issue was a way of storing it safely...
The biggest problem with hydrogen is NOT storing it safely. There are various solutions to that.

Rather the problem is hydrogen is not an energy source, like oil is. Rather it's an energy transport device, and it takes lots of energy to create hydrogen. We call our current situation an "energy crisis" because of the lack of clean energy, not because we're oversupplied with energy, just can't think of how to transport it.

If you had a vast supply of energy, whether fission, fusion or some other source, hydrogen would be one of several possible ways to use that for transportation. The problem is we don't have such a supply, and the inefficiencies and implementation costs of hydrogen make the core problem (lack of clean, renewable energy) worse.

As Ivan pointed out, it would take thousands of new fission plants to create enough hydrogen for the world transportation sector:

The world consumes 100 quadrillion BTUs of transportation energy per year, (2.9E16 watt hours). The hydrogen production, transport and fuel cell end-to-end efficiency is roughly 30%. A 1GW nuclear reactor produces 8.76E12 watt hours per year. So very roughly, you'd need (2.9E16 * 3.33) / 8.76E12 or 11,023 new 1GW fission reactors.

To provide 1/2 world transportation energy you'd need about 6,000 new reactors. To provide 1/2 of US transportation energy (roughly 4.39E15 watt hrs) you'd 1,670 new reactors. Currently there are about 100 reactors on line in the US, and they're all occupied producing utility energy.
 
  • #85
Ivan Seeking said:
And just for the record, I have been getting viable yields under far less than ideal circumstances - only about 60% of the light that things should have, and no CO2 added at all, only aeration.
By my calculations, at least 18,000 cubic meters of fresh air per gallon of biodiesel would be required to produce algae using aeration alone to supply the co2; e.g., 16 moles of c12h26 per gallon of biodiesel = 193 moles of CO2 required per gallon = 8.45kg co2/gal = 21,125kg of air per gallon @ 400ppm CO2 in air = 18k m^3 of air at 1.177kg/m^3.

What is your estimate for the energy cost of circulating 18,000 cubic meters of air through an algae bed per gallon of biodiesel produced? Ideally, forcing this much air under a layer of water of any given depth should cost about: 18k m^3 air X 10kPa/m pressure drop = 180MJ/m; so, what depth should we assume for the algae bed? You will need a very thin algae bed in order to minimize this cost, but so far you have only quoted biodiesel production in terms of acre-years (a three dimensional term); but what really seems to matter if you are planning to use aeration is the rate of biodiesel production per cc-year of an algae bed (a four dimensional term). Also, this raises an issue of how does this rate of production decline with depth; e.g., as you get farther (deeper) from the sunlight?

Of course there will be some evaporation of water (depending on the relative humidity of the fresh air) and hydrocarbon into the air, so:

What is your estimate for the average cost of hydrocarbon emissions to the forced air, and for cleaning this up once you are done with it? Do you plan to incinerate the HC emission, catalytically convert it, try to reclaim it somehow, or just vent it into the atmosphere?

And, what is your estimate for the average cost of replacing water lost to evaporation?

I have learned to quit betting the farm on what we will be able to do in the future - the future is often not what is promised...If one studies the algae option for a year and half as I have, it becomes apparent that some concerns mentioned earlier are not an issue. But at this point we are into proprietary information and I have to be selfish to protect my own interests...I have started a new company that will produce biodiesel from algae, and things are coming along very nicely.
I wish you the best of luck with your new company, but you really should not be raising issues here (especially issues that you have a personal financial interest in) unless you are prepared to defend your claims. If you aren't prepared to defend your claims, then you should withdraw them until such time as you are prepared to defend them.

Ivan Seeking said:
This is the fuel chain efficiency, and for petro I believe the efficiency is about 80% for gasoline.
This is roughly accurate for the average "Wells-to-Pump" (WTP) energy efficiency of gasoline production.

For corn ethanol the efficiency is usually cited as about 30%.
This is roughly accurate for the "Net Energy" of ethanol production. The WTP energy efficiency of ethanol production is 143% if the Net Energy is 30% then 143%=(100%/(100%-30%)).

Processing of biodiesel from algae is commonly cited as about 70% efficient - for every 100 BTUs worth of fuel, about 30 BTUs was spent growing the algae and processing the fuel.
If the Net Energy of biodiesel production is 70%, then the WTP energy efficiency of biodiesel production from algae is 333%=(100%/(100%-70%)).

Maybe that is a reasonable estimate for algae grown with CO2 from a coal-fired power plant under good climate conditions, I don't know; but I would doubt such a high estimate for algae grown under less favorable conditions such as with aeration.
 
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  • #86
Healey01 said:
And as a side note, has hydrogen been completely removed from our thoughts?...

...But I remember back in college about 5-6 years ago (I went to Kettering / GMI Tech) we had a talk (I think I can talk about this...) from GM I believe, where they, or someone, had developed a way to store hydrogen in reusable carbon plates. It was basically you could reuse the material to soak in hydrogen, and then dissolve it in your drivetrain somewhere to release the gas hydrogen. I believe both the plates and the chemical used to dissolve were both reusable in some sort of way.

You might want to glance at this thread.

https://www.physicsforums.com/showthread.php?t=170679

The algae to oil process is very interesting. The oil will no doubt be edible and, once refined, the price will naturally follow that of the other edible oils. In the event the oil is not of an edible nature, the price will follow that of the other fats (castor oil, jojoba, emu, etc...) that it is most closely related to from a chemical point of view. Can that price be justified without some government support?
 
  • #87
Aether said:
Maybe that is a reasonable estimate for algae grown with CO2 from a coal-fired power plant under good climate conditions, I don't know; but I would doubt such a high estimate for algae grown under less favorable conditions such as with aeration.

All worthy questions, but as I said, at this point the industry is competitive.

I don't feel compelled to give away 18 months worth of work in order to justify creating interest. A review of the industry will reveal that many approaches are considered and each has it own problems and benefits. You will also find that most people will not give away specific information. This is normal in any competitive industry. That's why I had to do 18 months of homework.

Most schemes utilize a number of systems, such as in this application.
http://xldairygroup.com/pressrelease.cfm?ContentKey=620
 
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  • #88
Ivan Seeking said:
All worthy questions, but as I said, at this point the industry is competitive.

I don't feel compelled to give away 18 months worth of work in order to justify creating interest.
Okay, that's why I didn't ask before; but then you referenced this thread here: https://www.physicsforums.com/showpost.php?p=1371139&postcount=67 and said
The problem is that there is only one crop that can produce enough biofuel per acre-year to satisfy the need for crude oil: Algae. Any other option will require more land for fuel crops than we have land...I have started a company to produce biodiesel from algae and am using 7500 gallons per acre-year as a standard.
If you want to present these as claims then you will have to defend them. If you aren't ready and/or willing to defend these claims, then you could preface your remarks with something like "I think...", or "I am investigating the possibility that maybe...", or something like that. Or, you could cite a credible reference that makes (and substantiates) the same claims.
 
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  • #89
Ivan Seeking said:
Most schemes utilize a number of systems, such as in this application.
http://xldairygroup.com/pressrelease.cfm?ContentKey=620
This is interesting, and I wish these people the best of luck with their project, but they seem to have some rather high expectations for their millk cows: 13,333 gallons of ethanol, 3,333 to 4,000 gallons of biodiesel, and 2,800 gallons of milk per cow-year!

That's 1.521 gallons of ethanol per cow per hour, 24hrs/day! How are they doing to do that?!? :bugeye:

Land Of Milk and Biofuel - Phoenix said:
When fully built, the $260 million ag-industrial complex planned by the XL Dairy Group will produce 100 million gallons of ethanol, 25 million to 30 million gallons of biodiesel fuel and 21 million gallons of milk a year...The firm will move in the first of 2,500 dairy cows in about three months to begin milk production, Corderman said. Also within three months, the company plans to begin construction on the second phase of the dairy, which will eventually house about 7,500 milk cows.
 
  • #90
Ivan Seeking said:
there is only one crop that can produce enough biofuel per acre-year to satisfy the need for crude oil: Algae. Any other option will require more land for fuel crops than we have land..

Aether said:
...If you want to present these as claims then you will have to defend them...

http://en.wikipedia.org/w/index.php?title=Biodiesel&oldid=142744380

It's basic math. The world consumes about 100 quadrillion BTU of transportation energy per year, much of which comes from crude oil. It's about 30 billion barrels per year (1.26 trillion gallons or 4.8E12 liters).

Corn ethanol yield is about 400 gallons/acre, sugar cane about 700 gal/acre, switchgrass about 800 gal/acre. Ethanol contains about 76,000 BTU/gal, so:

Acreage required to provide world transportation energy from corn ethanol: (100 quadrillion BTU / 76,000 BTU/gal) / 400 gallons/acre = 3.3 billion acres, or 13.3 million square km.

Acreage required to provide world transportation energy from sugar cane: 1.9 billion acres (7.7 million square km)

The entire North American continent is only about 26 million square km, so about 1/2 of the continent would be required using corn ethanol.

By contrast the biodiesel contains about 120000 BTU/gal, and yield/acre using algae feedstock is about 5000 gal/acre. So it has roughly 20x the energy yield per acre as corn ethanol, requiring about 1/20th the area.
 
  • #91
joema said:
Ivan Seeking said:
there is only one crop that can produce enough biofuel per acre-year to satisfy the need for crude oil: Algae. Any other option will require more land for fuel crops than we have land..
Aether said:
...If you want to present these as claims then you will have to defend them...
It's basic math...Acreage required to provide world transportation energy from corn ethanol: (100 quadrillion BTU / 76,000 BTU/gal) / 400 gallons/acre = 3.3 billion acres, or 13.3 million square km.

Acreage required to provide world transportation energy from sugar cane: 1.9 billion acres (7.7 million square km)

The entire North American continent is only about 26 million square km, so about 1/2 of the continent would be required using corn ethanol.
Then what basic math shows here is that we have more than enough land in North America alone to produce enough corn ethanol to satisfy world transportation energy demand, right?

joema said:
By contrast the biodiesel contains about 120000 BTU/gal, and yield/acre using algae feedstock is about 5000 gal/acre. So it has roughly 20x the energy yield per acre as corn ethanol, requiring about 1/20th the area.
Maybe so, but farm land is not the only input required for biofuel production. Concentrated CO2 is an essential input for economical biodiesel production from algae, and this is a scarce resource. Aeration can provide the CO2 required for biodiesel production from algae, but probably not cost effectively.

A.E. Farrell et said:
...ethanol constitutes 99% of all biofuels in the United States. -- http://rael.berkeley.edu/EBAMM/FarrellEthanolScience012706.pdf

It is interesting to note that corn crops not only utilize sunlight for photosynthesis, but they also utilize wind power for aeration. :cool:
 
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  • #92
Aether said:
Then what basic math shows here is that we have more than enough land in North America alone to produce enough corn ethanol to satisfy world transportation energy demand, right?
That's half the total land surface area, not all of which is arable. Much of the land area is mountainous or otherwise unsuited for crops.

Arable land in North America is about 1/8th the total land surface area, forests about 1/3.

If you mowed down all the forests to plant corn, and didn't use any corn for food production, plus diverted all other food crop acreage to corn, it still wouldn't produce enough ethanol.

This was discussed in the January 2007 Scientific American. They concluded if 100% of current U.S. corn production was diverted to ethanol production, it would supply only a tiny fraction of U.S. transportation energy. The same is true on a global scale.
 
  • #93
joema said:
That's half the total land surface area, not all of which is arable. Much of the land area is mountainous or otherwise unsuited for crops.

Arable land in North America is about 1/8th the total land surface area, forests about 1/3.

If you mowed down all the forests to plant corn, and didn't use any corn for food production, plus diverted all other food crop acreage to corn, it still wouldn't produce enough ethanol.
Maybe so, but that's not what you said before.

This was discussed in the January 2007 Scientific American. They concluded if 100% of current U.S. corn production was diverted to ethanol production, it would supply only a tiny fraction of U.S. transportation energy.
Your example above requires North America to supply world demand for transportation energy, but the Scientific American article is talking about U.S. corn production satisfying U.S. demand for transportation energy.

The same is true on a global scale.
Where does the Scientific American article say that?

It would be nice if corn ethanol alone could meet the current world demand for transportation energy, but I agree that it can't. U.S. energy security requires that we reduce our dependence on foreign oil. This can be done by a combination of conservation and alternative energy production. Corn ethanol is playing an increasingly significant role as an alternative energy source, and it already plays a far more significant role than biodiesel from algae (if aeration is required) will ever play.
 
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  • #94
Aether said:
Your example above requires North America to supply world demand for transportation energy, but the Scientific American article is talking about U.S. corn production satisfying U.S. demand for transportation energy.
My example does NOT require North America to supply world transportation energy, it was simply a familiar geographic illustration. E.g, the same acreage would occupy 134% of Europe, or 100% of Antarctica or 75% of South America. It doesn't mean you'd be growing corn in Antarctica. It simply illustrates the poor yield of current feedstocks requires continent-size acreage to produce enough biofuel to replace current sources.

Aether said:
Where does the Scientific American article say that?
Physics doesn't change when crossing a national border. The yield/acre may change modestly based on climate, but not sufficiently to alter applying the conclusions to a global scale. If the goal is actually solving the problem (vs making a marginal contribution) conventional biofuel feedstocks are very inadequate from a areal yield standpoint, no matter which ones are considered, or where they are grown.

Aether said:
U.S. energy security requires that we reduce our dependence on foreign oil. This can be done by a combination of conservation and alternative energy production. Corn ethanol is playing an increasingly significant role as an alternative energy source, and it already plays a far more significant role than biodiesel from algae...
The question is what alternative energy source is scalable to the vast industrial level to make a major difference.

Ivan's point was the yield-per-acre of all other current feedstocks (besides algae) is too low to achieve this. That doesn't mean corn, soy, etc. can't be a marginal contributor. But if you want to actually solve the problem, it requires much higher yield per acre.

It's possible there may be unforeseen problems with biodiesel production from algae that prevent scaling it up sufficiently, but at least the areal yield is there. By contrast other conventional feedstocks cannot possibly provide enough energy in the available acreage.
 
  • #95
joema said:
My example does NOT require North America to supply world transportation energy, it was simply a familiar geographic illustration. E.g, the same acreage would occupy 134% of Europe, or 100% of Antarctica or 75% of South America. It doesn't mean you'd be growing corn in Antarctica. It simply illustrates the poor yield of current feedstocks requires continent-size acreage to produce enough biofuel to replace current sources.
What I am saying is that your example and the Scientific American article aren't comparable. You should restate your example in the same context as the Scientific American article if you want to compare the two.

Physics doesn't change when crossing a national border. The yield/acre may change modestly based on climate, but not sufficiently to alter applying the conclusions to a global scale.
Per capita energy consumption for transportation does.

If the goal is actually solving the problem (vs making a marginal contribution) conventional biofuel feedstocks are very inadequate from a areal yield standpoint, no matter which ones are considered, or where they are grown.
Maybe so. In that case, energy conservation may have to make up the difference.

The question is what alternative energy source is scalable to the vast industrial level to make a major difference.

Ivan's point was the yield-per-acre of all other current feedstocks (besides algae) is too low to achieve this. That doesn't mean corn, soy, etc. can't be a marginal contributor. But if you want to actually solve the problem, it requires much higher yield per acre.
Either that, or effective energy conservation.

It's possible there may be unforeseen problems with biodiesel production from algae that prevent scaling it up sufficiently, but at least the areal yield is there.
The problems with biodiesel production from algae are not unforeseen. The aquatic biospecies program was closed down in 1998, and their website says that this subject is no longer a research priority. There has been no evidence presented here to show that there is any real yield (e.g., positive net energy) for biodiesel from algae grown using aeration.

By contrast other conventional feedstocks cannot possibly provide enough energy in the available acreage.
The real contrast here is that "...ethanol constitutes 99% of all biofuels in the United States", and biodiesel from algae grown using aeration contributes nothing.
 
  • #96
Aether said:
What I am saying is that your example and the Scientific American article aren't comparable. You should restate your example in the same context as the Scientific American article if you want to compare the two.
The issue which Scientific American highlighted (limited ethanol yield from current feedstocks making it impossible to supply a major % of U.S. transportation energy) also applies on a global basis for exactly the same reason.

Whether on a U.S. or global basis, there's a given need for transportation energy. Likewise on a U.S. or global basis, there's a given amount of available, arable land to produce this. For the exact same reason that ethanol cannot provide a major % of U.S. transportation energy, it likewise cannot provide a major % of world transportation energy: the yield per acre is too low for the available land and energy requirement.

Ivan's point was only a much higher yield feedstock is scalable to meet the necessary demand, and algae is one of the only (maybe THE only) feedstock with the necessary yield.

Aether said:
Per capita energy consumption for transportation does.
Per capita energy consumption is not relevant to the issue, which is whether any biofuel can be scaled upward sufficiently to supply a major % of U.S. or global transportation energy. It's not per-capita consumption that matters, it's total consumption.

Aether said:
In that case, energy conservation may have to make up the difference.
The difference is VASTLY too much for conservation to make up the difference. That doesn't mean conservation is wrong or shouldn't be used, only that it's inadequate to compensate for the insufficient yield from current biofuel feedstocks.

As the Scientific American article highlighted, ethanol (for example) can only supply a few % of U.S. transportation energy. On a global basis, the situation is similar. This means conservation would have to make up at least 80% of the current consumption, which is about 100 quadrillion BTU/year. It's simply not possible to reduce global transportation energy consumption by 80% via normal conservation measures within a timeframe meaningful to the problem. It would require a total restructuring of all society, akin to an asteroid hitting the earth, a nuclear war, or a global plague which decimates humankind.

Aether said:
The real contrast here is that "...ethanol constitutes 99% of all biofuels in the United States", and biodiesel from algae grown using aeration contributes nothing.

The issue is NOT what % of transportation energy is currently supplied by a given biofuel feedstock. Rather it's what biofuel feedstock (if any) can be scaled to the gigantic industrial level required to supply a major % of U.S. or world transportation energy. With ethanol from corn, soy, switchgrass, etc. it's clearly impossible. Algae at least is theoretically possible from a yield standpoint, plus can be grown on non-arable land so it doesn't displace existing crops.

That doesn't mean biodiesel from algae is the solution or is guaranteed to work. However ethanol from conventional feedstocks are guaranteed to NOT work, i.e, provide a major % of U.S. or global transportation energy.
 
  • #97
joema said:
Ivan's point was only a much higher yield feedstock is scalable to meet the necessary demand, and algae is one of the only (maybe THE only) feedstock with the necessary yield.
As far as I know algae has only been shown to produce a high yield per acre-year under laboratory conditions where it is was grown in a sealed container, in an ideal climate (good insolation), and supplied with concentrated CO2 from the exhaust of a coal-fired power plant. I expect that corn, and just about any other crop, would produce a spectacularly increased yield per acre-year under similar conditions. It seems reasonable to try and exploit available sources of concentrated CO2 for biofuel production, perhaps using algae, but this is not what Ivan is trying to do. He is trying to grow algae using aeration. Unless and until someone here explicitly claims, and then cites a credible reference (or makes a plausible argument) to substantiate that claim, that there is a positive net energy balance for biodiesel production from algae grown using aeration, then we should dismiss that claim. Don't you agree?

Per capita energy consumption is not relevant to the issue, which is whether any biofuel can be scaled upward sufficiently to supply a major % of U.S. or global transportation energy. It's not per-capita consumption that matters, it's total consumption.
The SA article presents an analysis of U.S. biofuel supply and demand, but not world biofuel supply and demand. This website presents data showing that there is a great variation in per capita energy consumption from one country to another: http://www.hubbertpeak.com/nations/percapita.htm. It is not reasonable to assume that the analysis presented in the SA article for U.S. biofuel supply and demand should also apply to the world as a whole.

The difference is VASTLY too much for conservation to make up the difference.
When the petroleum supply finally runs out, conservation can and will make up the difference. .

That doesn't mean conservation is wrong or shouldn't be used, only that it's inadequate to compensate for the insufficient yield from current biofuel feedstocks.
Ha ha...conservation is infinitely adequate for the task, I assure you.

As the Scientific American article highlighted, ethanol (for example) can only supply a few % of U.S. transportation energy. On a global basis, the situation is similar.
Per capita energy consumption in the U.S. is 697 times greater than it is in Afghanistan for example, and average per capita energy consumption in the rest of the world is several times lower than it is in the U.S.. So, again, it is not reasonable to assume that the analysis presented in the SA article for U.S. biofuel supply and demand should also apply to the world as a whole.

This means conservation would have to make up at least 80% of the current consumption, which is about 100 quadrillion BTU/year. It's simply not possible to reduce global transportation energy consumption by 80% via normal conservation measures within a timeframe meaningful to the problem.
Oh yes it is possible, and it will happen when the oil runs out. btw, I am not just talking about "normal" (I assume that you mean "voluntary") conservation measures, but also involuntary conservation measures and technological advances.

It would require a total restructuring of all society, akin to an asteroid hitting the earth, a nuclear war, or a global plague which decimates humankind.
Good. The sooner the better. I doubt that the advance of science in general and Moore's law in particular will be greatly hindered by such a restructuring. So what if we all wind up either riding bicycles or busses to work at some point in the future?

The issue is NOT what % of transportation energy is currently supplied by a given biofuel feedstock. Rather it's what biofuel feedstock (if any) can be scaled to the gigantic industrial level required to supply a major % of U.S. or world transportation energy. With ethanol from corn, soy, switchgrass, etc. it's clearly impossible.
I will not discuss "world transportation energy" with you using only the SA article as a basis. It is not reasonable to assume that the analysis presented in the SA article for U.S. biofuel supply and demand should also apply to the world as a whole.

Algae at least is theoretically possible from a yield standpoint, plus can be grown on non-arable land so it doesn't displace existing crops.
You keep talking in terms of "areal yield" and ignoring what I have said about the requirements for concentrated CO2 vs. aeration to produce biodiesel from algae. I am quite sure that fission has a vastly superior "areal yield" to biodiesel from algae in terms of kWh/acre-year. Don't you agree?

That doesn't mean biodiesel from algae is the solution or is guaranteed to work.
Ivan claims otherwise. He is claiming that algae can satisfy the need for crude oil. I have asked him to preface his remarks with "I think", or something like that, but so far he hasn't done that. So, I reject his claims as they stand. Don't you agree?

Ivan Seeking said:
there is only one crop that can produce enough biofuel per acre-year to satisfy the need for crude oil: Algae.

joema said:
However ethanol from conventional feedstocks are guaranteed to NOT work, i.e, provide a major % of U.S. or global transportation energy.
Ethanol displaces a marginal % of petroleum consumption which is useful, and this will become increasingly important as the supply of petroleum dwindles away. Who has claimed otherwise?
 
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  • #98
The anaerobic bacterium C. ljungdahlii, recently discovered in commercial chicken wastes, can produce ethanol from single-carbon sources including synthesis gas, a mixture of carbon monoxide and hydrogen that can be generated from the partial combustion of either fossil fuels or biomass. Use of these bacteria to produce ethanol from synthesis gas has progressed to the pilot plant stage at the BRI Energy facility in Fayetteville, Arkansas.
http://en.wikipedia.org/wiki/Clostridium#Commercial_uses

http://www.brienergy.com/pages/process01.html
 
  • #99
http://www.nytimes.com/2007/09/30/business/30ethanol.html
NEVADA, Iowa, Sept. 24 — The ethanol boom of recent years — which spurred a frenzy of distillery construction, record corn prices, rising food prices and hopes of a new future for rural America — may be fading.

Only last year, farmers here spoke of a biofuel gold rush, and they rejoiced as prices for ethanol and the corn used to produce it set records.

But companies and farm cooperatives have built so many distilleries so quickly that the ethanol market is suddenly plagued by a glut, in part because the means to distribute it have not kept pace. The average national ethanol price on the spot market has plunged 30 percent since May, with the decline escalating sharply in the last few weeks.

“The end of the ethanol boom is possibly in sight and may already be here,” said Neil E. Harl, an economics professor emeritus at Iowa State University who lectures on ethanol and is a consultant for producers. “This is a dangerous time for people who are making investments.”

While generous government support is expected to keep the output of ethanol fuel growing, the poorly planned overexpansion of the industry raises questions about its ability to fulfill the hopes of President Bush and other policy makers to serve as a serious antidote to the nation’s heavy reliance on foreign oil.

And if the bust becomes worse, candidates for president could be put on the spot to pledge even more federal support for the industry, particularly here in Iowa, whose caucus in January is the first contest in the presidential nominating process.

Two problems with corn-based ethanol - it's subject to fluctations in price, so price stability is an issue, and since more corn (one of two basic grains for animals raised for food) is used for ethanol, the price for foods based on corn increases.
 
  • #100
Astronuc said:
http://www.nytimes.com/2007/09/30/business/30ethanol.html


Two problems with corn-based ethanol - it's subject to fluctations in price, so price stability is an issue, and since more corn (one of two basic grains for animals raised for food) is used for ethanol, the price for foods based on corn increases.
There are people in this state pushing the sales of corn-fed stoves to heat homes. That's a pretty dumb thing to buy into, since corn has lots of better uses, and an increase in anyone of them can drive the price of corn (for heating) through the roof, as can a poor crop year. In a state that is almost completely forested, it's a no-brainer to get an efficient wood stove for heating, but still, people are buying corn-fueled stoves. Duh! People want to reduce their dependence on oil products price-controlled by OPEC and the domestic oil cartel, only to rush into the clutches of ConAgra, ADM, and other giant corporations controlling domestic agriculture. :confused:
 
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