The ethanol deception

[Ivan Seeking]

I was just watching a review of ethanol energy on CNN. They report that Consumer Reports claims that cars using ethanol see no decrease in mileage or performance.

Now I'm not sure what Consumers Reports claimed and a source wasn't cited, but the point of the story was to consider the performance of ethanol compared to gasoline, which was left somewhat vague in the end.

Gasoline has about 125,000 BTUs per gallon, and ethanol has about 76,000 BTUs per gallon. The last time that I checked, the conservation of energy law was still in effect.

Sidebar: IMO, nothing that Consumer Reports claims can be believed. This is not the first time that I have run across this sort of nonsense. In fact, just about anytime that I see a report from them on something that I happen to know about, they're wrong.

[JasonRox]

If the consumer doesn't feel like it decreased in performance or mileage, who gives a ****. The consumer is happy period.

It's not like they're saying it's scientific. It's a Consumer Report.

[Ivan Seeking]

If the consumer doesn't feel like it decreased in performance or mileage, who gives a ****. The consumer is happy period.

It's not like they're saying it's scientific. It's a Consumer Report.

It is a report FOR consumers that is supposed to be based on testing. Many people rely on their information when making buying decisions. Also, people are hoping to save money by buying ethanol fuel, when in fact the decrease in mileage will likely end up costing more than the savings gained by purchasing a cheaper fuel.

In order to replace petroleum with corn-ethanol, it would require about twice the land area of the US to grow the corn.

…a bushel of corn (56 pounds) on the Chicago Board of Trade has jumped from $1.86 at the end of 2005 to over $4 today…

Beef and poultry prices are likely to rise as animal farmers rely on corn for feed. … the price rise has already bumped up wholesale chicken prices 6 cents per pound.

Corn derived products serve a range of users including the food and beverage, pharmaceutical, paper products [corrugated and laminated paper], the textile and brewing industries, as well as the global animal feed markets.

"It ripples right across the economy.“
Reuters, May 19th, 2007.

[BobG]

I was just watching a review of ethanol energy on CNN. They report that Consumer Reports claims that cars using ethanol see no decrease in mileage or performance.

Now I'm not sure what Consumers Reports claimed and a source wasn't cited, but the point of the story was to consider the performance of ethanol compared to gasoline, which was left somewhat vague in the end.

Gasoline has about 125,000 BTUs per gallon, and ethanol has about 76,000 BTUs per gallon. The last time that I checked, the conservation of energy law was still in effect.

Sidebar: IMO, nothing that Consumer Reports claims can be believed. This is not the first time that I have run across this sort of nonsense. In fact, just about anytime that I see a report from them on something that I happen to know about, they're wrong.

I'd say they might be right depending on exactly what they said. The fuel going in may have a difference in energy content, but a lot of energy is lost between the 'in' and the 'output' - how much energy is applied to turning the tires. You have to take into account how efficient the combustion process is.

If the engine is designed for high ethanol fuels (i.e. - the engine has a high compression ratio), ethanol's performance is supposed to be roughly equivalent to gasoline. The engine wouldn't run at all on gasoline, which would currently be a pretty big drawback.

This wouldn't apply to flex fuel engines that can run on ethanol or gasoline. To use gasoline, the engines have to run with a lower compression ratio and you get much worse mileage with ethanol than you do with gasoline. In other words, you're right - in the same engine, it's impossible to get the same mileage out of ethanol that you do with gasoline.

The 10% ethanol mix that can be used by all engines also gets less miles per gallon than straight gasoline (about 3% less?), but the increase in octane gives better performance in other ways - I'd say it was a push depending on the driver's priorities.

[Ivan Seeking]

What is roughly equivalent, and where are these cars? I don't know of anyone driving one. Is this verifiable or more Consumers Reports information?

I don't see how after all of years of improvements in auto engines, we could get the same energy from 76,000 BTUs, as we do 125,000 BTUs.

[MeJennifer]

I was just watching a review of ethanol energy on CNN. They report that Consumer Reports claims that cars using ethanol see no decrease in mileage or performance.
Well before what you call "this sort of nonsense" and "deception" it might be good to do some due dilligence.

If we go to CNN.com we can find the article We want better mileage - but power and size, too (http://www.cnn.com/2007/AUTOS/05/24/cr_mpg_survey/index.html) placed today on the CNN website.

Nothing in this article indicates that Consumer Report claims anything like that.

If we look a bit further and go to the Consumer Report website we can find several articles where Consumer Reports states that ethanol is not more fuel efficient.

I include two articles:

(1) Ethanol: Growing renewable fuels (http://www.consumerreports.org/cro/cars/pricing/alternative-autos-and-fuels-1105/renewable-fuels/index.htm)

From this report:
"Ethanol contains less energy per gallon than gasoline, so E85 gets roughly 30 percent fewer miles per tankful. Factoring in that loss, corn-based ethanol sells for about $4.09 for the energy equivalent of a gallon of gasoline, making it more expensive than gasoline at today's prices."

(2) The ethanol myth: Consumer Reports E85 tests show that you’ll get cleaner emissions but poorer fuel economy ... if you can find it (http://www.consumerreports.org/cro/cars/new-cars/ethanol-10-06/overview/1006_ethanol_ov1_1.htm)

Your suggestion that Consumer Report is deceiving people by claiming that ethanol is not less fuel efficient is simply untrue. In fact Consumer Report is saying the contrary.

[Ivan Seeking]

I just saw it on CNN. Also, I said that they didn't cite a source

Usually what happens is that I see the report and it becomes available later for a link.

Now I'm not sure what Consumers Reports claimed and a source wasn't cited, but the point of the story was to consider the performance of ethanol compared to gasoline, which was left somewhat vague in the end.

[MeJennifer]

I just saw it on CNN.

Well then, shame on CNN.

Here is the Consumer Report press release:
Car buyers seek fuel efficiency, but remain wary of trade-offs
(http://www.consumerreports.org/cro/cars/news/2007/05/gas-price-survey-5-07/overview/0507_gas_price_survey_ov.htm)

[Ivan Seeking]

Perhaps... we will see later what is linked.

[Ivan Seeking]

In any event, ethanol has a reputation that is not deserved. It is a solution to nothing and puts food into competition with energy.

[Astronuc]

Certainly CNN is not scientific, but I believe Consumer Reports tries to be with a very limited sample, particularly when it comes to expensive items.

One thing CR cannot do is vouch for qualit (or quality control) of any particular item. We have relied on them, but with mixed success, although the experience has been more positive than negative.

[Ivan Seeking]

I've seen too many false claims to believe anything they say.

I had a buddy who owned the vaccuum shop in town, and one day he showed me a CR on two Eureka vacuum cleaners. One passed with flying colors and the other failed. What Tony was so amused with is that the only difference between the two models was the paint and decals.

[Ivan Seeking]

In fact, I'll do a little digging and see if I can find it, but, IIRC, some years ago they got caught on something like this and blamed it on outsourcing - they don't do much of their own testing.

[MeJennifer]

Talking about false claims, did you read the two links from Consumer Reports that I included? If you did you will have to admit that the statements about deceptions in this matter are simply unfounded.

[russ_watters]

I was just watching a review of ethanol energy on CNN. They report that Consumer Reports claims that cars using ethanol see no decrease in mileage or performance.

Now I'm not sure what Consumers Reports claimed and a source wasn't cited, but the point of the story was to consider the performance of ethanol compared to gasoline, which was left somewhat vague in the end.

Gasoline has about 125,000 BTUs per gallon, and ethanol has about 76,000 BTUs per gallon. The last time that I checked, the conservation of energy law was still in effect. Without knowing the nuts and bolts of the claim, it is tough to evaluate, but thermodynamically, "miles per gallon" (and therefore btu per gallon) is a largely useless thing to compare between fuels. The reality is that if you want to use ethanol in a car, you should change-out the fuel injectors to inject more ethanol, giving you in the end almost exactly the same thermodynamic efficiency and performance, but with more per-gallon or per-lb consumption.

Along a similar veign, most natural gas home heating furnaces can be converted to run propane and the basic difference is the orifice regulating the flow is different. Change-out the orifice and the performance is identical.

What is more useful is probably the chemical efficiency of the fuel. It is related somewhat to energy density, but fuels with a higher ratio of carbon to hydrogen (such as ethanol) produce less energy and more CO2.

[brewnog]

Energy content is pretty meaningless for performance comparisons between fuels. Ethanol is much more knock resistant than gasoline, therefore higher compression ratios can be utilised. Even on an unmodified (or gasoline) engine, ignition timing can be advanced, and charge density is increased due to the heat of evaporation of ethanol.

I'm not saying performance on ethanol is identical to that on gasoline, but then a gasoline-optimised engine isn't identical to one designed (or modified) for ethanol.

[BobG]

What is roughly equivalent, and where are these cars? I don't know of anyone driving one. Is this verifiable or more Consumers Reports information?

I don't see how after all of years of improvements in auto engines, we could get the same energy from 76,000 BTUs, as we do 125,000 BTUs.

You don't see any 100% ethanol engines on the road. For one thing, there's no where to fuel them up. You can see 33 of them on Sunday in the Indianapolis 500.

About the closest you might see functionally would be MIT's ethanol-boosted engine that only injects ethanol directly into the combustion chamber when extra power is needed. (http://web.mit.edu/newsoffice/2006/engine.html and http://www.psfc.mit.edu/library1/catalog/reports/2000/06ja/06ja016/06ja016_full.pdf) That's far from being on the road, either.

[Ivan Seeking]

Talking about false claims, did you read the two links from Consumer Reports that I included? If you did you will have to admit that the statements about deceptions in this matter are simply unfounded.

If you read the op, the claim of deception was applied to the use of ethanol. This was not primarily about Consumer Reports. I just happen to know from experience that CR is sometimes full of it, so the report didn't surprise me.

I will post the story a little later as it should come up after a few hours.

[Ivan Seeking]

You can see 33 of them on Sunday in the Indianapolis 500..

Just for perspective, didn't I hear that the use of ethanol was not based on performance, but other motives?

[Ivan Seeking]

Okay, I wasn't aware of the higher compression ratios possible, but since these cars are not available and the reality is what we actually have, ethanol probably offers no financial advantage.

And for anyone who want to do the calculation, when you see the 400 gallon per acre yields for corn, after the processing requirements, multiply by 0.3 [best case for corn] as the net gain. Others claim that the real multiplier is more like 0.1 or 0.2, and some even argue that the multiplier is 0.0 - that ethanol energy is just hidden petroleum energy and it is only competitive due to subsidies.

[Evo]

This fits into this discussion.

With the model, they can make tiny changes to the timing of the opening of both valves and ultimately optimize how engines run on alternative fuels.

"The major issue right now is that we have all these vehicles on the road today that are 'flex fuel' vehicles," Shaver said. That just means the gas tanks won't corrode and are chemically compatible with alternative fuels like ethanol.

"Alternative fuels do not combust the same way as conventional fuels. So you can put ethanol in your engine, but your engine will not efficiently burn that," Shaver told LiveScience. "

http://www.livescience.com/technology/070510_green_engines.html

[BobG]

Just for perspective, didn't I hear that the use of ethanol was not based on performance, but other motives?

The push for E85 and flex fuel engines are definitely for other motives. I'd agree with the Consumer Reports article MeJennifer linked to when it comes to the flex fuel engines.

The choice of ethanol over gasoline in Indy cars may not be entirely because of increased power.

NASCAR uses leaded gasoline to provide the extra octane needed to increase performance in cars that have to adhere somewhat to stock specifications - i.e. they can modify the engines, but they can't design an entirely new engine to stick in their car. Given the possibility of increasing the octane of gasoline or using ethanol, Indy cars use ethanol. Considering the amount of time lost in the pits to refuel during a green flag and the strategic advantages of getting a few extra laps per tank, the choice of ethanol over gasoline in Indy cars suggests that the performance/fuel economy trade off of ethanol must have some advantages over gasoline.

It's a pretty big stretch to say the principles of racing at 200 mph apply to city driving and I consider claims that mileage performance is equal to or better than gasoline engines a little dubious until a few 100% ethanol engines actually hit the street, hence the 'roughly equivalent' comment in my other post. You definitely wouldn't have the 30 percent fewer miles per tankful that the flex fuel engines have.

My point was CNN's claim might not be totally off the mark unless they start mixing in comments about engines designed for 100% ethanol with flex fuel engines. There's a big difference between the two and I'm not even sure what the point of the flex fuel engines is. Flex fuel engines won't motivate gas stations to start selling ethanol if no one is actually willing to use ethanol in their flex fuel engines. In fact, the disadvantages to actually using ethanol in a flex fuel engine will probably just make the obstacles for 100% ethanol engines even larger.

[Ivan Seeking]

The push for E85 and flex fuel engines are definitely for other motives. I'd agree with the Consumer Reports article MeJennifer linked to when it comes to the flex fuel engines.

I meant for Indy, not for the public. My understanding was that the switch was motivated entirely for environmental reasons [or even for the Indiana corn farmers?]. Or, perhaps this was some other form of auto racing that recently changed?

[Ivan Seeking]

The most important thing to realize is that we can't possibly grow enough corn, and even if we could, which we can't, food prices would go through the roof if ethanol became competitive.

For starters, sugar beets are a much better option for ethanol production.

[BobG]

I meant for Indy, not for the public. My understanding was that the switch was motivated entirely for environmental reasons [or even for the Indiana corn farmers?]. Or, perhaps this was some other form of auto racing that recently changed?

Indy racing changed from methanol to ethanol. They haven't used gasoline since the 60's. The switch reduced horsepower but increased fuel efficiency. http://www.fortwayne.com/mld/newssentinel/news/local/17206801.htm

[Ivan Seeking]

I want to add that I am not against the use of ethanol as a short term stop-gap solution as it could help in a crisis, and it is certainly great for the corn farmers, but the last thing that we want is a country or world covered with ethanol powered cars. In fact, for now and the foreseable future, it is not even possible.

[Aether]

Okay, I wasn't aware of the higher compression ratios possible, but since these cars are not available and the reality is what we actually have, ethanol probably offers no financial advantage.Ethanol burns at about 107% the thermal efficiency of gasoline due to the higher allowable compression ratios.

And for anyone who want to do the calculation, when you see the 400 gallon per acre yields for corn, after the processing requirements, multiply by 0.3 [best case for corn] as the net gain. Others claim that the real multiplier is more like 0.1 or 0.2, and some even argue that the multiplier is 0.0 - that ethanol energy is just hidden petroleum energy and it is only competitive due to subsidies.Per unit of energy output, corn ethanol production uses only about 8% of the petroleum input that gasoline production uses; it does use roughly as much fossil energy but mostly in the form of domestic coal and natural gas. The U.S. government is now investing heavily in the development of cellulosic ethanol production technology which could result in future ethanol production processes where virtually no net fossil energy is used for its production.

In order to replace petroleum with corn-ethanol, it would require about twice the land area of the US to grow the corn.How do you figure this?

The land area of the U.S. is 3,537,418 sq mi (http://www.infoplease.com/ipa/A0108121.html) X 640 acres per mile X 400 gal. ethanol per acre (per year?) = 905,579,008,000 gal. ethanol per year.

In 2004, the United States consumed about 140 billion gallons of gasoline (http://genomicsgtl.energy.gov/biofuels/transportation.shtml)

So, it seems to me that only 0.225 X the land area of the U.S. would be required to replace gasoline with corn ethanol (assuming that 1.5 gallons of ethanol is required to replace 1 gallon of gasoline).

[Ivan Seeking]

I get that from a 0.3 multiplier for production efficiency [net gain of 120 gallons per acre], and including all oil products. Also, you have to include the reduced energy output from real cars and trucks. Diesel engines are 40% efficient at 139,000 BTUs per gallon.

I should have figured that someone would object to that one. I'll get some links up tonight.

And what we are going to do in the future doesn't count. I've been fed that line for thirty years now, and estimates are almost always far too optimistic. For example, one common [historical] fallacy was that nuclear power would be too cheap to meter.

[rcgldr]

The avantage of ethanol in a race car is you can use more of it, the fuel to air ratio can be 2.3 times that of gasoline. At this point you get more power from ethanol than gasoline (not milage wise, just peak power wise). Champ cars (and their predecessors, CART cars from the 90's), also use ethanol and turbo chargers. Nitro methane, as used in fuel dragsters, uses an even higher fuel to air ratio for extreme (but hazardous) power.

Regarding production of ethanol, it's better to use sugar cane. Brazil is currently doing this. Farmers in the USA quit growing sugar cane because it was cheaper to import than to grow it hear.

[Aether]

I get that from a 0.3 multiplier for production efficiency, and including all oil products.Is the average ethanol yield 400 gallons per acre, or 0.3X400 gallons per acre? I think that you (or your sources) are mistaken about the petroleum input per gallon of ethanol, and that this error may be affecting your land-area calculation here.

Also, you have to include the reduced energy output from real cars and trucks.Since it takes 1.5 gallons of ethanol to replace one gallon of gasoline, I have revised my previous estimate to read "0.225 X the land area of the U.S. would be required to replace gasoline with corn ethanol." This is due to the reduce lower heating value of the fuel, and not due to "reduced energy output from real cars and trucks".

I should have figured that someone would object to that one. I'll get some links up tonight.Okay.

[Ivan Seeking]

I am running out of time and didn't spot the link that I used the other night, but what I am seeing during a quick search is even worse.

Right now, about 16 percent of the U.S. corn crop is going into ethanol production, but the fuel makes up less than one percent of U.S. demand for liquid fuels, once you take into account the amount of energy needed to produce the ethanol, Stephanopoulos said. Even if all U.S. corn went into ethanol production, there would only be enough for 4 to 5 percent of U.S. annual liquid fuel consumption....
http://www.physorg.com/news90166168.html

There was one paper talking about 3 parts in 10,000 gain, but I must not have understood the context.

The link I am looking for and forgot to save [either .edu or .gov] listed the net energy density as about 25 or 26,000 BTUs per gallon after processing [as a net measure of the gain]. So I will find that or a similar link, and will also link to a recent panel discussion on PBS in which opponents claim the gain is zero if the entire picture is considered. Again, this all applies to corn-ethanol.

These are more in line with my other reference.
http://www.usask.ca/agriculture/caedac/Ethanol/ethtable1.html

They show some optimistic estimates, but the real values for industry are much lower - listed as net gain of 38%. Also, some of these numbers seem inflated compared to other sources.

[Aether]

The link I am looking for and forgot to save [either .edu or .gov] listed the net energy density as about 25 or 26,000 BTUs per gallon after processing [as a net measure of the gain]. So I will find that or a similar link, and will also link to a recent panel discussion on PBS in which opponents claim the gain is zero if the entire picture is considered.This doesn't have anything to do with the amount of land area required to replace gasoline with ethanol. Your estimate of 2X the land area of the U.S. is clearly wrong.

[Ivan Seeking]

Ah, I think I see your point - the gains by not refining petro? What is the basis for your assertion? I haven't had the chance to make my case, and you never addressed the energy needed for all petro.

How much refined product do we buy? Right now we are importing refined products because we don't have enough here, so this is not energy that we pay for with energy.

And I want to pursue this, but clearly it is impossible to convert to ethanol from corn.

Also, as long as there are opponents arguing that the net gain is zero, there is a possibility that no any amount of corn could replace petroleum.

[Aether]

What is the basis for your assertion?Please see: A.E. Farrell et al., "Ethanol Can Contribute to Energy and Envoronmental Goals", Science, Vol. 311, p. 506-508, 27 January 2006 (www.sciencemag.org).The published results, adjusted for commensurate system boundaries, indicate that with current production methods corn ethanol displaces petroleum use substantially; only 5 to 26% of the energy content is renewable. The rest is primarily natural gas and coal (Fig. 2)...producing one MJ of ethanol requires far less petroleum than is required to produce one MJ of gasoline (Fig. 2).http://rael.berkeley.edu/EBAMM/FarrellEthanolScience012706.pdf

[BobG]

am running out of time and didn't spot the link that I used the other night, but what I am seeing during a quick search is even worse.



Right now, about 16 percent of the U.S. corn crop is going into ethanol production, but the fuel makes up less than one percent of U.S. demand for liquid fuels, once you take into account the amount of energy needed to produce the ethanol, Stephanopoulos said. Even if all U.S. corn went into ethanol production, there would only be enough for 4 to 5 percent of U.S. annual liquid fuel consumption....

http://www.physorg.com/news90166168.html

There was one paper talking about 3 parts in 10,000 gain, but I must not have understood the context.

The link I am looking for and forgot to save [either .edu or .gov] listed the net energy density as about 25 or 26,000 BTUs per gallon after processing [as a net measure of the gain]. So I will find that or a similar link, and will also link to a recent panel discussion on PBS in which opponents claim the gain is zero if the entire picture is considered. Again, this all applies to corn-ethanol.

These are more in line with my other reference.
http://www.usask.ca/agriculture/caed...ethtable1.html

They show some optimistic estimates, but the real values for industry are much lower - listed as net gain of 38%. Also, some of these numbers seem inflated compared to other sources.

This doesn't have anything to do with the amount of land area required to replace gasoline with ethanol. Your estimate of 2X the land area of the U.S. is clearly wrong.

How much corn you could get if the entire US were devoted to corn growing is irrelevant. Only 3.6% of US land is devoted to growing corn (81.6 million acres out of 2,264 million acres). Corn wouldn't be a very suitable crop for many areas of the country, so you can't just expand how much land is devoted for corn (or sugar cane for that matter) - hence the pessimistic numbers Ivan quoted. With higher corn prices (which ethanol would drive), you'd expect the amount of land devoted to growing corn or sugar cane to increase (109 million acres were devoted to corn in 1931), but it will still be a small percentage of total land in the US.

On the other hand, corn production has increased from 24.5 bushels/acre in 1931 to 148.4 bushels/acre in 2005. Even though the amount of acreage devoted to growing corn has decreased, the total production is 5 times higher than it was in 1931, while the population is a little more than double what it was in 1931.

http://www.ncga.com/news/OurView/pdf/2006/FoodFuelCharts.pdf
http://www.ers.usda.gov/StateFacts/US.HTM

If you produced ethanol only engines in addition to gasoline engines, we'd still probably be a net importer of fuel products, but we'd be importing less and have a wider selection of sources.

If you had engines similar to the MIT design, you'd decrease overall gasoline use without forcing users to decide between 3 types of engines (gasoline, deisel, ethanol). You'd keep a lot of the standardization that makes gasoline easier to sell. I'm not sure how important that would be since deisel is a pretty viable fuel, even if not as popular as gasoline.

In other words, ethanol isn't the magical cure to US fuel woes, but it could make them a little less painful.

[Averagesupernova]

Okay, I wasn't aware of the higher compression ratios possible, but since these cars are not available and the reality is what we actually have, ethanol probably offers no financial advantage.

And for anyone who want to do the calculation, when you see the 400 gallon per acre yields for corn, after the processing requirements, multiply by 0.3 [best case for corn] as the net gain. Others claim that the real multiplier is more like 0.1 or 0.2, and some even argue that the multiplier is 0.0 - that ethanol energy is just hidden petroleum energy and it is only competitive due to subsidies.


I'm not quoting this to argue the numbers. I want to point out that after the alcohol is taken out of corn there is alot of useful product left. It cannot be dismissed. If we need products from corn to start with, or any other crop for that matter, then what is the problem with getting the alcohol out of it when it will be grown regardless?

[Ivan Seeking]

I will be back later today or tonight. I wasn't ready with my links and need time to sort things out. I've been puting together a presentation for something else [related], and much of my information is in my notes at this point.

[Ivan Seeking]

If we go to CNN.com we can find the article We want better mileage - but power and size, too (http://www.cnn.com/2007/AUTOS/05/24/cr_mpg_survey/index.html) placed today on the CNN website.

Okay, that is the story referenced in yesterday's report. Apparently the news anchor had bad info as I think it was he who actually said that according to the CS study, ethanol was comparable to gasoline, when in fact their own report tells a different story, but they didn't show the entire report. It seems that what I saw was a leader story for this report. So it was the fault of CNN and CR got it right.

[Ivan Seeking]

Please see: A.E. Farrell et al., "Ethanol Can Contribute to Energy and Envoronmental Goals", Science, Vol. 311, p. 506-508, 27 January 2006 (www.sciencemag.org).http://rael.berkeley.edu/EBAMM/FarrellEthanolScience012706.pdf

I still need to take some time to review this - till now I have been trying to find a great link that I forgot to log and can't find. But for now, this gives an overview of the debate.

...The stickiest question about ethanol is this: Does making alcohol from grain or plant waste really create any new energy?

The answer, of course, depends upon whom you ask. The ethanol lobby claims there's a 30 percent net gain in BTUs from ethanol made from corn. Other boosters, including Woolsey, claim there are huge energy gains (as much as 700 percent) to be had by making ethanol from grass.

But the ethanol critics have shown that the industry calculations are bogus. David Pimentel, a professor of ecology at Cornell University who has been studying grain alcohol for 20 years, and Tad Patzek, an engineering professor at the University of California, Berkeley, co-wrote a recent report that estimates that making ethanol from corn requires 29 percent more fossil energy than the ethanol fuel itself actually contains.

The two scientists calculated all the fuel inputs for ethanol production—from the diesel fuel for the tractor planting the corn, to the fertilizer put in the field, to the energy needed at the processing plant—and found that ethanol is a net energy-loser. According to their calculations, ethanol contains about 76,000 BTUs per gallon, but producing that ethanol from corn takes about 98,000 BTUs. For comparison, a gallon of gasoline contains about 116,000 BTUs per gallon. But making that gallon of gas—from drilling the well, to transportation, through refining—requires around 22,000 BTUs.

In addition to their findings on corn, they determined that making ethanol from switch grass requires 50 percent more fossil energy than the ethanol yields, wood biomass 57 percent more, and sunflowers 118 percent more. The best yield comes from soybeans, but they, too, are a net loser, requiring 27 percent more fossil energy than the biodiesel fuel produced. In other words, more ethanol production will increase America's total energy consumption, not decrease it. (Pimentel has not taken money from the oil or refining industries. Patzek runs the UC Oil Consortium, which does research on oil and is funded by oil companies. His ethanol research is not funded by the oil or refining industries.)[continued]
http://alt-e.blogspot.com/2005/07/alternative-fuel-ethanol-fuel.html

Also, sure, it is possible to divert the energy demand to other sources, but this does not make ethanol truly competitive as an alternative. It becomes more of an energy carrier rather than an energy source. So in this sense ethanol would be more like hydrogen, in which case we might as well just make hydrogen. And we don't need to load-up the grid driving alternative options. This is one point on which even Russ and I agree.

Also, BobG's quote
How much corn you could get if the entire US were devoted to corn growing is irrelevant. Only 3.6% of US land is devoted to growing corn

Combined with an optimistic estimate given earlier
Right now, about 16 percent of the U.S. corn crop is going into ethanol production, but the fuel makes up less than one percent of U.S. demand for liquid fuels, once you take into account the amount of energy needed to produce the ethanol, Stephanopoulos said. Even if all U.S. corn went into ethanol production, there would only be enough for 4 to 5 percent of U.S. annual liquid fuel consumption....

we come up with a demand of ~20 or 25 X 3.6% = 72% to 90% of the land area of the US, so already we are close to my statement of twice the land area without getting specific about where all of the petroleum energy goes, and at what efficiency. But it is true, when I figured this I was not assuming that we in effect cheat by diverting the energy of processing to other sources as this really doesn't solve the basic problem.

Oh yes, apparently that number of 3 parts in 10,000 gain [0.03%] was for cellulosic ethanol from corn, which I know nothing about at this point.

Also, note that the values will vary quite a bit from source to source, including the raw energy densities.

[Ivan Seeking]

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.

Here are some more good links including:
Ethanol fuel from corn faulted as 'unsustainable subsidized food burning' in analysis by Cornell scientist
http://www.news.cornell.edu/releases/Aug01/corn-basedethanol.hrs.html

http://journeytoforever.org/ethanol_energy.html

Overall, we use about 100 quads [quadrillion BTUs] of energy each year from all sources, and in 1998 [easiest reference], 38.8% of this energy came from petroleum.

We can consider the typical efficiencies of diesel to include most petroleum energy [when taken with the estimates earlier for the ethanol needed for gasoline], and then consider how much ethanol we need to replace this. In fact we might just be generous and assume that ethanol would be as efficient as diesel as a starting point.

The total demand for refined products is listed here
http://tonto.eia.doe.gov/dnav/pet/pet_cons_psup_dc_nus_mbbl_a.htm

For 2005, I count about 3 thousand million barrels of fuel oil at 42 gallons per barrel, and assuming 139,000 BTUs per gallon, we get a total of 1.75E16 BTUs. Now, if we assume the same efficiencies for ethanol at [76,000 BTUs per gallon] as we get from the fuel oil, we get 2.3E11 gallons of ethanol, and at 30% yields we need 7.8E11 gallons, or about 1.7E9 acres of corn to replace diesel fuel and oil used for heat. This would be in addition to the ethanol needed for gasoline, so as you can see, we can easily get to absurdly large numbers and about twice the land area of the US at 2.2E9 acres. But again, this assumes that we don't steal energy from other sources to make the ethanol. And of course the potential error is fairly large, but we are working in units of nuclear bombs anyway, and we can get close enough for perspective. Also, we assumed the ethanol would be as efficient as diesel, and today it's not, so we might add as much as another 30% to our 1.7 billion acres. And lastly, I don't know of any large trucks that run on ethanol.

Now should we consider aviation?

When I used the word deception, I didn't mean to imply that there is a conspiracy. No doubt most scientists and enthusiasts are sincere in supporting their position in this issue, whatever that may be, but the idea that ethanol is a real option is clearly a fallacy at this time. And we need to think about the options that exist today.

Ethanol from corn may be an alternative fuel, but it is not an alternative.

[Aether]

Also, sure, it is possible to divert the energy demand to other sources, but this does not make ethanol truly competitive as an alternative. It becomes more of an energy carrier rather than an energy source. So in this sense ethanol would be more like hydrogen, in which case we might as well just make hydrogen. And we don't need to load-up the grid driving alternative options. This is one point on which even Russ and I agree.Ethanol today could be considered largely an energy carrier rather than an energy source, but: Our best point estimate for average performance today is that corn ethanol reduces petroleum use by about 95% on an energetic basis and reduces GHG emissions only moderately, by about 13%.Ethanol today is effective at reducing U.S. dependence on foreign oil today. Ethanol may also have a future as a primary energy source.

...the idea that ethanol is a real option is clearly a fallacy at this time. And we need to think about the options that exist today.If you have an alternative in mind (biodiesel?) then please compare it to ethanol directly.Although biofuels offer a diverse range of promising alternatives, ethanol constitutes 99% of all biofuels in the United States.

[Averagesupernova]

Ivan you haven't commented on my first post. My point is that you cannot count all of the fuel it takes to raise a crop since that crop is used for other things even after the alcohol is taken out. If you intend to calculate the amount of fuel it takes to get a unit of ethanol in the manner that they are in your post #39 then you have to assume that no crop was raised prior to ethanol production which is completely false and that no other products come from the crop once the ethanol is taken out which is also completely false. I do not wish to argue for or against ethanol from crops I just want to point out that the methods arrived at figuring gains/or losses are bogus.

[Ivan Seeking]

Ethanol today could be considered largely an energy carrier rather than an energy source, but: Ethanol today is effective at reducing U.S. dependence on foreign oil today. Ethanol may also have a future as a primary energy source.

If you have an alternative in mind (biodiesel?) then please compare it to ethanol directly.

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.

From everything that I have seen on the web and in my own testing, it was just a matter of time and price. It appears that algae became competitive [hit the break even point] about mid 2004 at ~40 a barrel for crude. It should be a viable option at today's prices.

Also, keep in mind that much of the literature focuses on making algae competitive at much lower prices, which it isn't, but today this is likely not an issue.

[Ivan Seeking]

Ivan you haven't commented on my first post. My point is that you cannot count all of the fuel it takes to raise a crop since that crop is used for other things even after the alcohol is taken out. If you intend to calculate the amount of fuel it takes to get a unit of ethanol in the manner that they are in your post #39 then you have to assume that no crop was raised prior to ethanol production which is completely false and that no other products come from the crop once the ethanol is taken out which is also completely false. I do not wish to argue for or against ethanol from crops I just want to point out that the methods arrived at figuring gains/or losses are bogus.

We can't play shell games: We have to look at the real costs to produce what we need. We have to assume that we create new farmland to produce the fuel since we clearly don't have enough now [unless we plan to stop producing food]. And byproducts are great, but when we start talking about twice the land area of the US, they don't count for much. It is clearly not a viable option in the big picture. But as I stated earlier, it might be used to ease the crunch as it is today.

I also suggest that even if we could grow enough corn, due to the amount needed, most byproducts would not be valuable due to supply and demand. This has already happened in the biodiesel market. One byproduct is pure glycerin, which now has relatively little value due to the amount of biodiesel produced.

However, as a best case perhaps, a byproduct of algae is... algae. :biggrin: After getting the biodiesel, in principle it can be used to produce ethanol, and then hydrogen, but I don't know if this has ever been done in a practical way. Also, people are working with algae for hydrogen and ethanol production alone, so the picture is bigger than just biodiesel, but down the road - another "future" option. Still, one important concept wrt algae is the carbon all goes somewhere - either as sugars for ethanol, or hydrocarbons [fatty acids] for biodiesel. As it turns out, the most efficient path today is for hydrocarbon production.

The residual mash can be used as a high quality feed for cattle, or as fertilizer for other food or algae crops.

[Ivan Seeking]

Oh yes, 400 X 400 miles X 640 acres/ sq. mile X 10,000 gallons/acre X 118300 BTUs per gallon = 120 quads.

So maybe 80 quads in practice. Again, we use about 100 quads from all souces, and when you sort it out a bit, the efficiencies don't change the picture greatly. And to replace just petroleum, but all petroleum, which unlike ethanol, biodiesel could since it could be used in the trucking and other industries [and is currently being tested for aviation], we would only need about 39% of this, or about 250 X 250 miles of land or water [good farmland not needed]

But the point of this thread was to show that based on the technology that we have today, ethanol, and esp ethanol from corn, is not a long term solution to the energy problem. Some even argue that it is part of the problem [a net loser].

Late edits: Going to back a point made earlier, we can also reduce this requirement [land needed for algae] as we do use energy to transport crude from other counties, and then to refine it here. I think the avg chain efficiency for petro fuels is a little under 80%, so we can legitimately derate the requirements accordingly. I need to check on the exact number though; that is about what I think it was...

[Averagesupernova]

We can't play shell games: We have to look at the real costs to produce what we need. We have to assume that we create new farmland to produce the fuel since we clearly don't have enough now [unless we plan to stop producing food]. And byproducts are great, but when we start talking about twice the land area of the US, they don't count for much. It is clearly not a viable option in the big picture. But as I stated earlier, it might be used to ease the crunch as it is today.

I also suggest that even if we could grow enough corn, due to the amount needed, most byproducts would not be valuable due to supply and demand. This has already happened in the biodiesel market. One byproduct is pure glycerin, which now has relatively little value due to the amount of biodiesel produced.

However, as a best case perhaps, a byproduct of algae is... algae. :biggrin: After getting the biodiesel, in principle it can be used to produce ethanol, and then hydrogen, but I don't know if this has ever been done in a practical way. Also, people are working with algae for hydrogen and ethanol production alone, so the picture is bigger than just biodiesel, but down the road - another "future" option. Still, one important concept wrt algae is the carbon all goes somewhere - either as sugars for ethanol, or hydrocarbons [fatty acids] for biodiesel. As it turns out, the most efficient path today is for hydrocarbon production.

The residual mash can be used as a high quality feed for cattle, or as fertilizer for other food or algae crops.

I'm not sure what you mean by 'play shell games'. The simple fact is that X acres of crop will be raised regardless of whether we take ethanol out or not. So until ethanol usage shorts some other product that requires the carbohydrate, NOT taking alcohol out is the most inefficient way to go. Residual mash left from ethanol from corn is also a high quality source of feed for cattle. It's a good protien source commonly known as distillers grain. I'm betting that there is alot more residual left from corn after distillation than alcohol. We all need to remember that we need to eat too which has always been and hopefully always will be the main role of agriculture.
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I'm certainly not saying that ethanol from corn is a cure all. Obviously it's not. My point is that the method arrived at determining the net gain/loss is bogus and you can't/won't see it.

[Ivan Seeking]

The fact is, already the use of ethanol has doubled the corn prices - food and energy are in competition, and we see the result. And we have barely scratched the surface.

Where is that benefit again? Earlier I posted a Reuters quote showing that chichen prices have started to rise [up 6 cents a pound for wholesale at that time], and there is upward pressure on beef prices, all because of ethanol. There are already a million [figuratively speaking] uses for corn and corn products, and anything using these products will be affected.

And it is not true that demand for ethanol will have no impact on how much corn we grow - supply and demand says otherwise.

[Averagesupernova]

I would bet a years pay that corn prices will not stay at current levels for any length of time. And I'm not talking about a 5 to 10 year trend. If they do, everything else will inflate along with. In 1996 corn spiked well over $5.00 per bushel. It happens every so often. You are talking very short term. Take a look at corn prices over the last 30 years and you'll see what I mean. Food is already in competition with energy. It takes energy to get food and until everyone moves back to small farms and things go back to manual labor it will remain so.
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Anyways, that is not my argument, so please don't even bother. My point is (which you've ignored) the method used to determine the net gain/loss of energy in ethanol production. Crops will continue to be grown as they always have so the same amount of fuel will be expended to do so with or without taking the ethanol out. It makes me wonder what else is overlooked in all of the other energy source schemes being dreamed up.

[Ivan Seeking]

You seem to forget that we need the corn grown today. This is not a surplus grown for no reason.

The increased cost of corn is attributed directly to ethanol, but the other market forces still apply, so we would expect to see tremendously high spikes in the future if ethanol production increases significantly. When we apply the law of supply and demand, and we create a huge new demand, the prices will certainly rise accordingly. This is basic economics.

[Ivan Seeking]

Another advantage that biodiesel has today [without even growing algae yet] is that the feedstock base is highly diversified - we can and do use many different kinds of plants as a source- so the impact can be spread out over many different products. For example, in some areas the source is canola, others cotton seed, and in many areas we make it from soybeans. Rapeseed is another strong source of feedstock today.

I think the majority of biodiesel in the US is coming from soybeans right now, but this is driven by demand. As the demand increases, more crops will come online with greater capacity. In principle it could help ALL farmers, and not just corn farmers.

I know that Willie Nelson [BioWillie] drives a Mercedes that runs on cotton seed biodiesel.

He has a sticker on the front window: No War Required. :biggrin:

[Ivan Seeking]

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.

[Averagesupernova]

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.

[Ivan Seeking]

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.

[Averagesupernova]

Ivan where do you get the 1.5 times energy density of biodiesel compared to ethanol? How is that figured?

[Ivan Seeking]

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.

[Averagesupernova]

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?

[Ivan Seeking]

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?

[Aether]

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".

[Averagesupernova]

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.

[Aether]

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/.

[Ivan Seeking]

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.

[Aether]

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.

[Ivan Seeking]

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.

[Ivan Seeking]

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.

[Aether]

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%.

[Ivan Seeking]

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].

[Aether]

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.

[Ivan Seeking]

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.

[Ivan Seeking]

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.

[Aether]

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: 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

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.

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. Future options don't count. When they are viable, then they become part of the discussion....the technology faces many R&D hurdles before it can be practicable...

[Ivan Seeking]

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.

[Aether]

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.

[Ivan Seeking]

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.

[Ivan Seeking]

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.

[Ivan Seeking]

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.

[joema]

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

[turbo]

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.

[Ivan Seeking]

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:

[glondor]

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.

[joema]

Biodiesel from algae: http://www.unh.edu/p2/biodiesel/article_alge.html

U.S. Aquatic Species Program (research to produce biofuels from algae): http://en.wikipedia.org/wiki/Aquatic_Species_Program

Overview of algaculture (farming from algae): http://en.wikipedia.org/wiki/Algaculture

[Ivan Seeking]

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.

[K.J.Healey]

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.

[Ivan Seeking]

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.

[joema]

...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.

[Aether]

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.

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.

[chemisttree]

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.

http://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?

[Ivan Seeking]

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

[Aether]

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: http://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.

[Aether]

Most schemes utilize a number of systems, such as in this application.
http://xldairygroup.com/pressrelease.cfm?ContentKey=620This 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:

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.

[joema]

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..

....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.

[Aether]

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......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?

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.

...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:

[joema]

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.

[Aether]

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.

[joema]

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.

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.

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.

[Aether]

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.

[joema]

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.

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.

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.

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.

[Aether]

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?

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

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?

[Astronuc]

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

[Astronuc]

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.

[turbo]

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 any one 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:

[Astronuc]

http://www.npr.org/templates/story/story.php?storyId=18784732
All Things Considered, February 7, 2008 · At first blush, biofuels such as corn ethanol and soybean diesel seem like they would be great from the standpoint of global warming. The crops soak up carbon dioxide from the atmosphere as they grow, and that balances out the carbon dioxide they produce when they're burned. But until now, nobody has fully analyzed all the ripple effects of this industry. And Tim Searchinger, a visiting scholar at Princeton University, says those effects turn out to be huge.

"The simplest explanation is that when we divert our corn or soybeans to fuel, if people around the world are going to continue to eat the same amount that they're already eating, you have to replace that food somewhere else," Searchinger says.

Searchinger and his colleagues looked globally to figure out where the new cropland is coming from, as American farmers produce fuel crops where they used to grow food. The answer is that biofuel production here is driving agriculture to expand in other parts of the world.

"That's done in a significant part by burning down forests, plowing up grasslands. That releases a great deal of carbon dioxide," Searchinger says.

In fact, Searchinger's group's study, published online by Science magazine, shows those actions end up releasing huge amounts of carbon dioxide. The study finds that over a 30-year span, biofuels end up contributing twice as much carbon dioxide to the air as that amount of gasoline would, when you add in the global effects.

Unintended consequences.