The Energy Balance of Ethanol versus Gasoline
Posted by Robert Rapier on August 28, 2006 - 1:04am
Topic: Alternative energy
Tags: eroei, eroi, ethanol, gasoline, politics, vinod khosla [list all tags]
I am trying to spend more time writing on topics other than ethanol. But I get a lot of e-mails on that subject, and often have 3 or 4 mini-debates going on at a time via e-mail. I just finished a debate involving a government official and some big names over the energy balance of gasoline versus ethanol. There still seems to be a lot of confusion surrounding this issue, so I asked for permission to publish the exchanges. I was reluctantly given permission, provided I deleted the personal information from the government official (name and government agency). The exchange involved myself, a government official that I will refer to as "Tom", Michael Wang from Argonne, and Vinod Khosla.
Mr. Rapier,If your assessment of the ethanol fuel cycle energy balance (and its comparison with the petroleum fuel cycle energy balance) is right, then not only is Vinod Khosla wrong, but many others of us in the energy community -- including the U.S. Department of Energy and Argonne National Laboratory (see attached summary) must also be wrong.
Attached was a summary of an Argonne National Lab report written by Michael Wang, who initiated the following claim (from the report):
As you can see, the fossil energy input per unit of ethanol is lower--0.74 million Btu fossil energy consumed for each 1 million Btu of ethanol delivered, compared to 1.23 million Btu of fossil energy consumed for each million Btu of gasoline delivered.
I must admit that appeals to authority don't impress me much, especially when I know the person making the argument is completely wrong. Remember, this is coming from a government official involved in alternative energy. So, I responded:
Tom,They are wrong. I have read all of the Argonne studies. I have exchanged e-mails with Wang at Argonne and Shapouri at the USDA. They know they are being misleading in these claims, but most people don't dig into the details to see their sleight of hand.
Here is a very simple test that will demonstrate they are wrong. After people work through this, they always see the problem. Let's say my goal is to make 1 BTU of liquid fuel. Will I consume more energy if I produce ethanol, or will I consume more energy if I produce gasoline? The implication from the Argonne et al. would imply that it should take more energy to produce the gasoline. However, that is not remotely the case. If I presume an energy balance for ethanol of 1.3, then I will consume 1/1.3, or 0.77 BTUs to make 1 BTU. My net is a mere 0.23.
If, however, I make gasoline, the efficiency is 80%. That is where the 0.8 number comes from. In this case, I only consumed 20% of the BTUs to make 1 BTU of gasoline. My net is 0.8 BTUs. What they have done is convolute energy return and efficiency, and act like 1.3 for ethanol is the same metric as 0.8 for gasoline, when they are actually 2 different metrics.
As I like to say, there may be some legitimate reasons for using ethanol. Efficiency of production is one of the most misleading arguments out there. It just isn't true. And I will gladly debate Wang or anyone at the DOE in print regarding these misleading claims.
Tom responded, copying Michael Wang at Argonne and Vinod Khosla (they were copied on all messages from this point).
Robert,As I see it, the fallacy of your reasoning (similar to that of Pimentel's and Patzek's) originates, at least in part, from an "all Btus of energy are created equal" viewpoint. If continued /expanded use of petroleum was indeed feasible, sustainable, environmentally and politically acceptable, etc., then perhaps your conclusion, that petroleum is a more "efficient" energy option than ethanol, would be more valid -- i.e., just keep burning the petroleum Btus and continue to accept the bottom-line energy result (albeit a continually worsening one in any petroleum-depletion scenario) that the luxury of stored fossil fuel deposits afford us: by reinvesting a fraction (1/5 today but steadily increasing) of the recovered petroleum energy, we can continue to harvest what's left.
But the production of ethanol and other biofuels (which, by the way, should include a broader focus, encompassing other forms of pure and mixed alcohols, biodiesel-type fuels, bio-crude type fuels, etc.), along with other kinds of bioenergy, offers a means of harvesting Btus of solar energy and incorporating this contribution from solar energy into today's transportation energy supply -- an achievement that has thus far proved elusive via other means, such as electric vehicles or hydrogen.
The fact that today's investment of 1 Btu of fossil energy in the ethanol fuel cycle delivers "ONLY" 1.3 Btus of ethanol to the vehicle fuel tank (the added 0.3 Btu being solar energy incorporated into the fuel cycle) is actually a very beneficial energy result, especially given that this result only gets better with technology advances, potentially including production from cellulosic biomass. Meanwhile, the energy reinvestment necessary to capture remaining petroleum resources promises only to become greater. Ask yourself this question: If producing and operating hybrid electric vehicles (which I suspect have their own underestimated trade-offs besides the obvious higher cost factor), in order to make petroleum Btus go about one-third further, makes good sense in today's energy world, then why doesn't achieving essentially the same result via ethanol production and use (with at least incrementally, if not fundamentally better results in store) offer at least as attractive an option?
While I don't think I would personally try to argue that the ethanol fuel cycle is twice as efficent as the petroleum fuel cycle (i.e., by comparing a 1.3-1.6:1 ratio to a 0.8:1 ratio), neither do I find your analysis compelling from an energy standpoint; in fact, it appears even more misleading. I believe that most of us in the transportation energy community -- along with many in the automotive industry, the oil and other energy industries, the environmental and global climate change communities, etc -- have come to accept the results of Argonne National Laboratory (as summarized in the U.S. DOE webpage document I forwarded to you earlier) as the most authoritative and fair assessement thus far of ethanol's net energy (and greenhouse gas) implications.
Michael Wang also weighed in, to say he wasn't getting involved:
Dear Mr. Rapier,Instead of wasting everyone's time, let me just simply pointing out that I do not recall that I have extensive communication with you and I do not intend to do so, because of your statement "I have exchanged e-mails with Wang at Argonne and Shapouri at the USDA. They know they are being misleading in these claims, but most people don't dig into the details to see their sleight of hand."
You are entitled to have your opinion, but do not imply personal attack on my professional work.
Michael Wang
I answered both with my next response:
Tom,There is no fallacy in my reasoning, and my arguments have nothing to do with Pimentel's and Patzek's. To suggest they do indicates that perhaps you still don't understand my argument.
Unlike Pimentel and Patzek, I am using Argonne's numbers to make my point. Your argument, "If continued /expanded use of petroleum was indeed feasible, sustainable, environmentally and politically acceptable...." is a different argument than the one you originally started off with. You are suggesting that there are other reasons for using ethanol. Fine. But you are not addressing the point of my argument, which is simply that ethanol is far less efficient to produce than gasoline, despite the proponent's claims to the contrary. Argue the sustainability issues. Argue the environmental issues. But don't mislead people by suggesting that it takes more energy to produce gasoline than to produce ethanol. That is an incredibly ludicrous claim.
My argument is not misleading at all. It does not convolute efficiency and energy return. It is a measure of the amount of energy that must be consumed to produce two different fuels: gasoline or ethanol. That is a very simple metric, and is not in any way misleading. Wang's metric is misleading, and I am sure that he is well aware that people are misusing it. When people say "ethanol is 1.2, but gasoline is worse at 0.8", they have compared two different metrics. When you write that you accept the authority of Argonne/DOE with respect to the net energy and greenhouse implications of ethanol, you are once again addressing a different argument. Please do not address Red Herrings, since I have accepted their net energy results for ethanol in my analysis.
Regarding Wang's communication with me, I still have it if he would like for me to refresh his memory. I pointed out the same thing I have pointed out here, and his response was essentially "Yeah, but you are looking at the total energy inputs, and there are many different ways to look at this problem." I do not regard the debunking of misleading claims as a waste of anyone's time. I would think that Wang would want to defend his work against critics like myself, especially given that most of it has not been subjected to scientific peer review. Again, I will debate Wang, Shapouri, or anyone else who wishes to argue that it is more efficient to produce ethanol than gasoline. If you want to argue about something else, then you aren't addressing the argument I am making. Yet this is exactly what you did in your second response.
Finally, I want to make it clear that my comments are not meant to defend the status quo. I want to see us move away from fossil fuels as quickly as we can. I am merely using the gasoline versus ethanol issue to show why these claims of higher efficiency of ethanol production are fallacious.
This response covers my biggest gripe about people who want to debate this issue. If I rebut a specific claim, they gallop off to a different claim. That is exactly what Tom did.
At this point, I also asked if they minded me publishing the exchange:
Incidentally, do you have any problems with me publishing this exchange? I will publish it without changing a word, and will include Wang's statement that he doesn't recall having extensive communication with me. I think the public can benefit from these exchanges. I understand your position quite well, however I hope it is clear that you didn't actually address my arguments, but instead addressed other reasons for supporting ethanol.I am confident that my argument as written is completely accurate and not in any way misleading, and I have no problem being judged by public opinion on its merits. I am a strong supporter of publicly debating these technical issues, and I have no interest in misleading anyone. But I also have no interest in allowing people to be misled.
Vinod Khosla weighed in next:
Robert's argument would make solar cells a horrible source of energy at an efficiency of 0.15! And why would we ever use electricity?Most modern ethanol plants being built have an energy balance of around 1.5 -1.6 as they try and minimize their energy use for cost reasons. That coupled with the higher use efficiency of ethanol energy than petroleum energy (25% less mileage even with 33% less energy is the accepted EPA rating for most flex-fuel cars - the SAAB 9-5 Biopower with Turbo is only 18% less mileage) gives an ethanol "fossil fuel efficiency" of about 2X per mile driven. The current California plants we are building don't especially ship corn (they are built around cattle feedlots where the corn has been shipped in for years) and they don't dry the distillers grain since they use it locally at the feedlot, does better than the 2X number. The E3 Biofuels plant in Mead Nebraska achieves an "energy balance" of five for CORN ethanol according to a report I saw from the National Commission ion Energy Policy.
It is time to stop asking the wrong question of "energy balance" or even the somewhat less wrong question of "energy balance relative to petroleum" but rather ask the two right questions (a) how much petroleum use can we displace per gallon of an alternative liquid fuel and (b) what is the green house gas reduction per mile driven.
For nuance we might add (c) at what cost of production per mile driven (to take away the short term price manipulation going on and (d) in what vintage of plant? Modern, average, old, coal fired, gas fired, with and without dry distillers grain, all the way to the E3 Biofuels model. Today the economics of reducing energy cost work.
I responded to Mr. Khosla's argument:
The solar cell argument is not valid, as several people pointed out on The Oil Drum, because it confuses efficiency with energy return. The instantaneous efficiency may be 15%, but you can get that day after day. The total energy returned from a solar cell far exceeds the energy that went into creating it.The reason we use electricity is because we convert coal, something not especially useful for doing work in its natural form, into a form in which it can do useful work. That is not the case with most of the fossil fuels that go into making ethanol. We turn natural gas, gasoline, and diesel, all perfectly good transportation fuels, into ethanol. We capture a bit of solar energy in the process, but grain ethanol is primarily recycled fossil fuel. And while this argument has focused on the marginal energy return, not included in those assessments (as Wang can attest to) are the secondary inputs, nor effects from soil erosion from growing corn, or herbicide and pesticide runoff into our waterways.
For the record, I fully support, and have advocated the E3 Biofuels model. In fact, I spoke with their project manager this week for an hour on the phone. I was also recently quoted in National Geographic endorsing the E3 process:
New Ethanol Plants to Be Fueled by Cow Manure
However, a couple of things need to be clarified. Their plant has not yet started up, so claims of energy return from this process are premature. It is definitely a step in the right direction, and I would prefer to see all new ethanol plants built around a similar model.
Regarding "wrong questions" and "right questions", that misses the entire point of my arguments, which are quite simple. There is a horrendous level of misinformation out there surrounding ethanol. When someone claims that Brazil farmed their way to energy independence, or that it is more energy efficient to produce ethanol than gasoline, or that ethanol produces no greenhouse gases - those are claims that must be addressed. Ethanol policy should not be made based on misinformation like this. My agenda is simple, and that is truth in advertising. I am a skeptical scientist by nature, and I feel like these claims deserve critical technical scrutiny. It is not my goal to kill grain ethanol, unless it deserves to die. But we won't know that without an honest debate, and too little of that is taking place. My goal is to separate hype from what the science actually indicates, and pursue those solutions that make the most long-term sense. Corn ethanol, which has been the primary target of my criticism, is not a very efficient use of our resources as it is currently produced. On this, I know that Mr. Khosla agrees with me, because we have spoken at length about this.
Tom indicated that he really didn't want to have this debate in public:
I'm inclined toward Dr. Wang's (and Mr. Khosla's) viewpoints that it is somewhat of a distraction and probably unproductive to pursue this debate with you further or participate in your forum -- especially in light of your unfortunate characterizations of individuals' and organizations' work ("sleight of hand"?). In any case, since you say you accept Argonne's basic analytical results, then this entire debate is all about the interpretation and implications of these results (and who is "right" trying to answer the academic question "Which is the more "efficient" fuel, ethanol or gasoline"), which I don't foresee being resolved in this forum.
I once again tried to convince Tom to take this debate into the public arena:
How else do you characterize the comparison of an EROI for ethanol to an efficiency of gasoline, other than sleight of hand? A straightforward assessment would be to consider either EROI to EROI, or efficiency to efficiency. Perhaps it wasn't Dr. Wang's intention to have this issue so thoroughly muddled, but the public has certainly muddled it. I have lost count of how many times someone claimed that it is twice as efficient to produce ethanol as to produce gasoline.My impression then is that you do not want this exchange made public? If we posted this at The Oil Drum, it would be read by a tremendous number of people, and would have advocates on both sides. If your argument is correct, then you should have no concerns given that I will post this exchange verbatim. I think these are the kinds of open exchanges that need to take place so people can sort out hype from truth. My main objective is education, and I think it would certainly suit that purpose.
We exchanged 1 last pair of e-mails that I won't entirely reproduce (because I told Tom I wouldn't). Suffice to say that Tom agreed to publication, provided I removed some information on him and his organization. In his final response to me, Tom accused me of rancor (passion is not the same as rancor!), questioned whether my rancor explains my e-mail identity (tenaciousdna), and once again invoked the argument from authority, suggesting that my argument was subjective and merely my opinion, and he and all those other authorities couldn't be wrong. Needless to say, my reply was "pointed", but I offered to take up the matter with him at any time.
This exchange may help explain why I haven't been posting as much lately, which some have asked about. These things take up a bit of my time every day, so I decided to kill two birds with one stone and make a post out of this debate. Let this also serve as a warning to those who want to bang heads with me. :-) If you want to win a debate with me, make sure you are arguing from a factual position.



Clearly the ethanol advocates are not concerned about net energy. Mr Khoslas comment
entirely misses the point that replacing one gallon of oil that society receives leverage of 10-15 times with one gallon of ethanol which society gets .3-.6 'leverage' implies borrowing resources from other areas of the non-energy economy in order to produce the ethanol. This does not imply that ethanol in itself is a bad product, but misses the larger issue that the commodity its trying to replace is truly awesome in its impact on our world, and cannot be replaced easily. See A Net Energy Parable for a primer on net energy.Also, (although you take Argonnes results as given), I disagree with their boundaries of analysis, especially for long term sustainability purposes. When doing energy (or financial) analysis, we need to include the widest boundaries possible. Oil is so ubiquitous in our societies transportation, that to count all the energy inputs is nearly impossible. If oil triples in price, can we assume all products necessary to make ethanol will be available, irrespective of price? (like steel for pipelines, new trucks, highway maintenance, tractors, fertilizer, farm tools, labor, insurance, etc). Furthermore, Argonne models assumed the best yields and states for growing corn. To use corn ethanol nationally, it needs to be trucked because it picks up water in normal oil pipelines. This energy cost isnt factored into the models. Also, a tankful of ethanol can transport a car only 70% as far as a tankful of gasoline, so requires more fillups and driving 'downtime'.
Most importantly, the ethanol debate is ignoring multicriteria analysis and your critics are focusing exclusively on the irrelvance of the energy balance. Energy may or may not ultimately be the limiting factor in corn ethanol infrastructure. What is the Energy Return on Soil Invested? or Energy Return on Water Invested? These questions are not being addressed because currently we have bumper crops and the ecological deficits are not being calculated in financial ethanol models.
If government subsidies were removed and full ecological and societal boundaries were used in the analysis, corn ethanol would take the same path it did in the 1970s.
Is there a reliable evaluation available for the amount of water required to produce a gallon of Corn Ethanol, including Ag inputs and whatever would be involved in refining, if any? I think that this argument, which is already very valuable, needs to start adding some of the other very real costs of building a dependency on Ethanol, to add to the Eroei question. Whether Khosla or 'Tom' or Wang is convinced of that particular Value Judgement, I think the costs of this 'alternative' need to include some of the other costs that laypeople will recognize as a vital part of the equation.
(Those who think regular people can't add might not agree with this. I think people are smart when given good information and a chance to process it)
Bob Fiske
(should your discussions start up with the gentlement again, you can use New Orleans as a good example of how authority always gets it right. er, wrong)
PS: Can you recommend a good summary document that lays out the Ethanol debate succinctly? I need something that I can pass by people to engage them before losing them...
However, I find your case regarding the enrgy balance unconvincing. It seems to me that in the case of gasoline, you start with one unit of crude (in BTU terms) and wind up with .8 units, albiet far more useable ones.
In the case of ethanol, the inputs are much more diverse, but may or may not be more useable. You have one unit of mixed inputs mainly coal (to create the steel and electricy inputs), and natural gas (fertilizer, electricity). I don't think the gasoline and diesel inputs really count. They could be offset by using ethanol and eventually will be to some degree. However, we don't produce trucks, etc. that run on ethanol. In this case all that happens is a quantity of liquid fuel is added to both the numerator and the denominator. This reduces the ratio, but doesn't involve the waste of any energy.
So you do put in one unit of scattered energy sources and get back 1.2 (or more) units of ethanol.
I agree that crude oil on its own is not useful and coal/natural gas are. I also think the measure is somewhat arbitrary as crude to gas is only one stage in a process. Comparing the entire cycle from stuff in the ground to useful product is more meaningful.
I don't think it is useful to compare crude to gasoline with coal/natural gas/corn to ethanol. But I am not sure that the argument is actually wrong.
That is one of Roberts main points. He is rightly pointing out that the efficiency of gasoline is being compared to the (slightly positive) energy balance of ethanol. To start from the stuff in the ground, oil/gasoline beats ethanol by a factor of 20 (or more)times, depending on boundaries.
Ethanol does in fact transform some solar energy into usable fuel. But its replacing something that is millions of years of stored solar energy that is more energy dense and of higher quality. To reiterate, if ethanol has an EROI of 1.3:1 and the entire find/refine/distribute oil/gasoline cycle has an EROI of 8:1, then gasoline, from a societal perspective, has 7/.3 =23.33 times more energy return than corn ethanol.
If some of the produced ethanol is used to replace the gasoline and diesel inputs, then that ethanol is no longer available to society, which means smaller input and smaller output. While this might lead to higher net energy, it would require a larger scaling of non-energy inputs.
We have time to aim, fire and shoot only a few alternative energy bullets (along with reducing our energy footprint as a culture). Corn ethanol is a misguided shoot from the hip national waste of one of these precious bullets. I too am tired of rehashing these arguments, but smart well intentioned people are confused. 3 ethanol plants are being built every month, and a year from now there will be 8 built every month, largely coal fired. When the grain ethanol bullet is fired, it will take a decade before the bullet stops. Which is why its important to not go down this path, at least not nationally.
However, I see the arguments for and against as being equally confusing. My objective isn't to promote ethanol, particularly grain-based. I have no opinion as yet on cellulosic, but have no reason to believe it is any better at this point.
However, I do think that sugar cane-based ethanol makes sense in a certain regions and only to a scale not greater than 10% of current global consumption.
I think the lack of care in referring to corn-based ethanol as if it is all ethanol is no less confusing than the pro-ethanol falsehoods. I think that failure to be clear that the accusations are only accurate in referring to a specific process (grain) is as willful and wroimg as any from the other side. The same goes for damning ethanol (or any other potential solution) just because it can not replace every bit of oil product we now use.
YOUR problem!!!
Why is it that we have to rehash these arguments again and again among TOD posters?
You should have made up your mind one way or another and be able to support your position by at least PLAUSIBLE arguments even if challengeable and challenged.
If you don't know what you are talking about keep reading and STFU instead of spreading your confusion.
Even without the 'TF' in the middle of it, 'Shut Up' is beneath you or any of us.
Bob Fiske
40 more being built.
7 existing facilites are being expanded.
Not only has the path been paved but they're putting up lights.
Thus:
gasoline: 1 BTU (petroleum) input -> 0.8 BTU output
ethanol: 1 BTU (mix hydrocarbon) input -> 1.3 BTU output
In this context, inputs are just inputs; they may be, but are not necessarily, consumed. It seems inappropriate to ignore the "input" of oil that becomes gasoline, just because it isn't literally consumed (i.e. burned) in the process. You still have to put it in the front end, in order to get product out the back end.
Calculated this way, ethanol does beat gasoline. Fine, so be it. But it's a very simplified metric, and the net benefit, while positive, is small.
I think that this entire arguement is really a distraction from the bigger question of appropriate energy policy. The detractors of corn ethanol are wasting their time splitting hairs over the definition of efficiency or EROIE, at least in the context of public debate. The points that need to be made, loudly and clearly to the public, are these:
- If you're concerned about peak oil, ethanol is no solution. It's positive, but it's not positive enough to offset rising demand coupled with declines in production.
- If you're not concerned with peak oil, but just want to reduce oil use (e.g. for national security reasons), then ethanol is still a waste of time. The externalities are very high, and the return on investment is low compared to energy efficiency measures.
The pro-ethanol lobby has completely bollixed those who are interested in actual sane, sustainable energy policy by focusing excessive attention on the energy return question. And the ethanol detractors have, for the most part, fallen for it. We need to stop dancing to their tune, and talking from their frame. Instead, accept their arguements as being "close enough" to correct, and demonstrate why those arguements are not sufficient to support a national move towards ethanol.Disclaimer: all the above statements are specifically about corn ethanol. Sugarcane ethanol is a different story, and cellulotic ethanol is a largely unknown story (and is therefor not a proper basis for making energy policy, IMO).
Tony
What is the difference between the coal that goes into ethanol and the oil that goes into gasoline?
In either case you start out with one of them (coal or oil) and at the end you don't have them anymore, but you do have a liquid fuel.
I understand and agree that the energy input to crude is something along the lines of the figures you cite. I acknowledged this in my initial comment.
But isn't the same true for coal. The energy input to get the coal is much less than the BTU content. It seems to me that you count one way or other, but make it consistent for both.
NO!
It it very precisely stated by sofistek and you just reject it with NO backing argument, hand-waving isn't an argument.
So let's say you expend 1 unit of energy. For oil production, you get, say, 5 units of raw material for producing your gasoline. If those 5 units are converted at 80%, then you end up with 4 units of energy available for every unit of energy expended. With ethanol, the 1 unit of energy expended results in some biomass that is then converted to 1.2 units of available energy. So the available energy with gasoline production is far higher than ethanol (4 units, versus 1.2 units), for the 1 unit of energy expended in producing those fuels.
You can do the same calculations with coal. I think it's only confusing for those who want a different outcome from those calculations.
Tony
I'm sorry if I am seeming oppositional. I don't want to believe one outcome or the other. I have said separately that I do not think corn-based ethanol is viable. I appreciate your patience.
However, I am still not convinced. Here is how I see it (oversimplified):
Ethanol:
Start with one BTU of coal
End up with 0 units of coal and 1.25 BTUs in the form of ethanol
Gasoline:
Start with one BTU of oil
End up with 0 BTUs of oil and .8 BTUs in the form of gasoline
I still see the distiction between converted and consumed as meaningless. Energy can not be created or destroyed, so really both are converted.
Actually, I also agree that this conversation is a side issue and not that important. I think the process of growing corn and running an ethanol refinery is more destructive and expensive than running a refinery. Again, corn ethanol is not worth the effort and the oil to gas / energy to ethanol comparison is trivia rather than analysis. However, I do not think you can say Robert is right and other are wrong.
If the process produced more energy (like sugar cane) or used less resources (water, land, etc), ethanol can make sense.
- Corn: You consume 1.0 BTU of coal to convert one unit of raw material (corn) into 1.2 BTU of ethanol.
- Crude: You consume 0.2 BTU of coal to convert one unit of raw material (crude) into 1.0 BTU of gasoline.
IMHO, the energy content of the raw material is irrelevant.Jack
Think of the problem as follows.
1 bushel of corn contains X Kcal of raw energy. Produced from an input of sunlight, water, fertilizers, natural gas (or coal,) inputs from liquid fuels that go into cultivation and harvesting equipment. Of that raw energy (corn energy + other input energy) only E% gets converted to ethanol.
This E% is what you should be comparing to the 80% figure that is quoted for gasoline.
The solar energy in ethanol and the original energy content of the crude oil are 'found' energy sources and aren't properly included in the equation.
If you want to speak of closed systems and account for all externalities, then every single chemical process has a negative ROIE.
Vinod is arguing that taking all our fossil fuels, putting it 1 BTU at a time into the "black box farm" equipment + fertilizer, and getting 1.3 BTU of ethanol out, is better than taking 1 BTU of oil, putting it into a "black box refinery", and getting 0.8 BTU of gasoline out. I think I'd agree with him on that narrow point, IF it's completely sustainable, esp because it's more useful fuel than, for example, coal.
The reality is that
A) Capacity is almost as important as efficiency. If your average farmer can make an energy profit, but isn't making enough total to drive to walmart every weekend and buy groceries, you have a problem. Likewise, yields are low enough that we are highly farmland limited, meaning that we can't really offset a significant portion of the country on corn ethanol, no matter if someone works out the microeconomics (which I think Vinod is working on, entirely dependant on government subsidies) or the energy economics.
B) 1.3 ROI is horribly difficult to work with. Right now we have an oil infrastructure that supplies hundreds of thousands of people with margins on which to live, and those margins are taken out of a 10-20x energy balance. Do you think our current version of society can survive if it requires 30x as many people to be working the mines or the fields?
No. But two points:
The thing that strikes me here is starting with one BTU of coal. As ever, we're still depleting a fossil resource. Where is the renewability factor?
Again, with sugar cane-based ethanol, the non-renewable inputs are far smaller (10-15%) and could come from hydropower (which haas its own problems - but is "renewable"). Given this ratio the ethanol is far closer to renewable and the impact on the climate is far less.
I think I would be more comfortable with:
Start with one BTU of ethanol
End up with 0 units of ethanol and 1.25 BTUs in the form of ethanol
It's the same as RR's challenge to run an ethanol plant on its own energy stream. (like we routinely do in petroleum refineries). I mean this literally: run the farm equipment on ethanol, the transport trucks (to/from) the distillery on ethanol and the distillery on ethanol. Test a closed loop system.... measure everything... the irrigation water volume, the fertilizers, all ethanol inputs to equipment and distillery operations.
No sarcasm is intended here... this seems like a terrific project for the University of Iowa. Let's prove out the facts on the ground.
Investing in ethanol is investing in politics (and subsidies). Right now it is rewarding venture capitalists, farmers, and politicians at the expense of precious fertile land and water resources in an attempt for continuing our "nonnegotiable" lifestyle. A big issue in addition to debating EROI with these guys is how the time, resources, and government money could be better spent. One of the big absurdities of ethanol is its temporary nature. Each year the corn needs to be grown and transported and processed under a different set of circumstances (drought conditions, storms, etc.) Let's compare that to spending our efforts on expanding rail in this country, and wind and solar into our electrical grid. Those efforts would be much more long-lasting as well as meeting future needs in our "nonnegotiable" powerdown. Ethanol is leading us farther down the road to industrialized farming and an inability to feed ourselves if and when we face oil shocks. These ethanol supporters assignment should be to read "Omnivore's Dilemna". It is my own belief that these ethanol plants won't be operating in the near future because of increasing cost of fossil fuel inputs, constrained government budgets limiting subsidies, GW causing increased crop failures and increasing public acceptance of the fallicies of ethanol. As soon as politicians realize that more votes can be gained by opposing ethanol, their story will change. Robert, keep up the good work and thanks for all that you do.
The production of green fuels benefits each and every one of us, not just venture capitalists, farmers and politicians.
Moreover, as the US ethanol industry is in its infancy, I suggest that it will be around for some time to come as new technologies, best practices and 2nd generation production paths begin to take hold -elements all- of a rapidly expanding and exciting sector whose actors are well aware of the hurdles in front of them.
It's naive to assume that ingenuity does not have a place in the grain->ethanol world especially as ethanol producers such as E3 and others are right now proving otherwise by implementing cogen energy streams wherever possible.
Or build a windmill using just wind. Try that!
Actually in the case of ethanol it can be done, it is just impractical and expensive to create a custom, parallel infrastructure.
I could come close with the industrial structure of Iceland.
Electric arc smelting today creates ferro-silicon alloys and could be used for simpler alloys. Massive sources of aluminum (Al blades instead of fiberglass). Towers from Al.
Recycled copper from autos melted down by electric arc.
Ammonia plant closed down recently, could be used for many organic chemicals with modest changes.
Iceland has superb wind resources, but better hydro & geothermal resources.
But seriously, why do you feel that the closed loop operation "has to be done" for ethanol, but not for other renewable energy energy sources?
I just proposed that we compare wind to ethanol.
Maybe you should contribute the $100 million
Actually, if an existing Iowa ethanol plant could be used, as well as existing wind generators already near Ames, and EROEI data were collected for 1 year's time by Iowa State, it could and probably would end up saving taxpayers millions in ended ethanol subsidies, both on a federal and a state level.
Why do you not want to see this done??
If Iowa or any other state would retrofit farm equipment and tankers to run on pure ethanol and produced all of the fertilizer from ethanol and waste, it would improve the EROEI greatly by subtracting from the numerator and denominator. Building the hardware for a windmill or distillery is going to be tough.
I think what you would find is that ethanol does have a positive EROEI, but that wind is much better. If the analysis also included other externalities, such as water use and environmental/climate impact, the gap would be greater. If you were to extend the comparison to end use at the cars tires, even better.
I am pro-wind and unenthusiastic at best about corn-based ethanol. I just want to be fair.
So if you are going to do it, let me know. I'll even contribute.
A combine can cost a farmer $250,000 and not even include the header(the big part in front).
Most all equipment runs on diesel. Long life is one reason. They are built tough. Storage of fuel is not a big problem. It also used to be cheaper than gas.
Asking them to shuck all their diesel equipment and invest in new E85 or ethanol running engines is just not going to happen IMO. At least not in any short time frame.
Refit? I doubt that diesel engines would be 'convertible'. The injection pumps and the compression ratios would likely not be prone to such modifications. Gas in a diesel engine spells destruction.
Farmers run on a very tight budget. Sometimes a crop year is just break even and I am not talking 'corporate farms' nor am I talking 'family farms'.
I am talking the 'operator' who owns manybe 200 - 500 acres and rents or sharecrops another 1500-2000. This is enough acreage (in the midwest) to give him a reasonable ability to make some large expenditures and expect a reasonable return.
They tend to always be in debt also. Without the lender signing off on such purchases that also will not happen.
The deep south,plains and other areas may differ.
Also I do not see them jumping thru hoops to trash all their seeders and combines/headers just to go to 'switch grass' or some other exotic. They have been into corn,wheat and soybeans for a long enough period that they can be sucessful with a background of knowledge. Throw milo in as well.
Most here who speak of 'we'll grow sugar cane or whatever' just don't seem to grasp the real concepts of agriculture/farming. Like they can and will just switchover with no problems.
Proposing ethanol and assuming that farmers would just switch over is not a viable assumption IMO. I think they would just stick with what they have or sell out.
I see very few of the younger generation out here in the fields. Most who try it don't care for it. The ones that are hired to do the work are your basic 'day labor' types. They do not understand much beyond what they are told to do. Putting them on a $80,000 tractor is senseless in my opinion but thats exactly what happens.Myself I wouldn't trust most on a go-cart.
Late model tractors and other equipment is quite hi-tech these days. Lots of sensor based equipment. Lots of controls and actuators that are driven by embedded modules.
Try explaining then how to pull up the DTC's and understand what they say is nigh impossible. They use these men/boys because they can't afford to pay much in wages and thats all thats available.
In fact, hydro is limited and its use already has knock on effects that were not envisaged. All energy sources are limited, because it takes limited resources to harness them.
The key is to get to a state where we are using resources sustainably (or effectively sustainably). Let's not distinguish between renewable and so-called non-renewable resources, since renewable can become non-renewable if consumed too rapidly.
Tony
Start with one BTU of coal
End up with 0 units of coal and 1.25 BTUs in the form of ethanol
Gasoline:
Start with one BTU of oil
End up with 0 BTUs of oil and .8 BTUs in the form of gasoline
In chemical engineering terms, your numbers are correct, but meaningless. Those numbers are apples and oranges; they represent two different energy balances. The ethanol numbers are an approximation of the total overall energy balance for ethanol production, including farming, transportation, etc. The gasoline numbers are a refinery energy balance. Expand the gasoline energy balance to be on the same basis as the ethanol one and there is no 1 BTU of oil input; there is .2 BTU of energy input to get the oil. The oil, unlike the coal, no longer crosses the boundary of the energy balance.
Setting correct boundaries for mass and energy balances is ChemE 101. I find I agree with RR; to get something so elementary wrong is deliberate obfuscation.
I know oil has a positive EROI because there is gas at the gas station. I'm with Will upthread. Lets see it done completely independent of any other energy source.
Call it the original car .
Now get to 600 million descendants with corn. It's just preposterous.
Take a barrel or a BTU or crude oil, use a fraction of it to heat it up and it will fractionate for you. No simple McCabe-Theile diagram, to be sure, but the principles are still the same. For many light and medium crudes you end up with a straight-run gasoline/naptha cut that is a blend of alkanes and aromatics. It does not burn well in ICE's except at high altitude where lower octane ratings are acceptable, but with a little more processing (energy), you get mixtures that are acceptable as gasoline with the proper vapor pressure and and resistance to predetonation (knock).
Moreover, there are many products you get from the processing and all can be derived from the original heat content of that barrel (or BTU) of crude (I know this is a simplification of the many refining process steps and internal loops within a refinery, but it can be argued that the energy required to make all the refineries products is self-contained within the feed itself. On this point, the fact that any products actually leave as a result of the crude feed is evidence of the "relatively small" amount of energy required to refine oil to useful products including gasoline).
What is missing from this ethanol discussion, however, is the energy content of the stuff (cellulose, corn, whatever) used to derive ethanol as part of the original heat input. To be "competitive" with crude oil used in making a gasoline product, biomass derived ethanol (including corn) would have to derive all the energy for processing from the biomass itself. This has been a great sticking point for ethanol production for many years. Adding coal (and then forgetting the required mass and heat content of the biomass) leads to the incorrect conclusion that you and others have summarized....use a BTU of coal get 1.25 BTU of ethanol.
CHE 101 should tell you there is something fundamentally wrong with that part of the energy equation, particularly since you are totally relying on a chemical reaction to derive ethanol. A CHE 300 course (or higher) would tell you why that is so (thermodynamics and PChem).
Remember with most conventional oil, the gasoline fraction is already there "dissolved" in the mixture. We might use cracking and reforming to derive a larger fraction of gasoline from the original crude, but the gasoline cut is almost always "there" and all the energy required to derive it is there also.
Corn has an advantage over most cellulosic biomass in that it has containers sugars that are amenable to fermentation processes to create ethanol. Note that this requires a "weak mash" to have the yeast fermentation process work with subsequent separation/distillation required to bring the ethanol up to usable strength. Also not that about half of your mass (and energy) leaves as carbon dioxide.
Cellulosic ethanol has other added disadvantages. First, most biomass under consideration (on a dry weight basis) contains only about half that weight as cellulose. The other 50% is split pretty evenly between hemi-cellulose and lignins. About half of your available energy for chemical conversion is "lost" right here in the separation of cellulose from the dry biomass. You can concentrate and burn most of those lignin/hemicellulose based materials to provide energy for the process (much as an acid sulfite pulp mill does, and other pulping processes which have their own chemical recovery processes).
The trick in recovering the cellulose from the biomass is not to dissolve the cellulose into an unrecoverable form. However, once you've separated the cellulose, it's easy to see (from it's chemical structure) why it prefers to degrade to methanol. The steps of hydrolyzing the cellulose to glucose and then fermenting to ethanol are the next hurtles to get over. Just as with corn ethanol, even if your conversion of cellulose is very efficient, you have the same loss of mass/energy associated with the carbon dioxide fermentationation process.
The point is that before you've gotten very far, nearly 75% of your energy potential (as ethanol) is gone. This does not include any additional steps such as distilling/concentration that are futher energy drains on the original heat content of the raw material. So, if you've consumed 0.75 BTU of the original biomass content just to get to 0.25 BTU of ethanol, there is no easy way to 1.25 BTU out of the process alluded to in several posts throughout this thread. Rather, it might take you 5 BTU of biomass and 1 BTU of coal to produce 1.25 BTU of ethanol.
You cannot forget what already crossed that imaginary boundary to act as the source of ethanol when you draw the energy box. And this does not consider any of the energy required to get it there in the first place.
Besides, if the numbers were that good, we'd skip this biomass stuff and just go to direct conversion of coal to ethanol and figure out the energybalance later.
One can develop an energy cycle not dependent upon coal but it requires a substantially greater amount of biomass AND a certain amount of that biomass bypassing the ethanol process just for it's energy content.
Please feel free to visit www.syntecbiofuel.com.
Here you will learn that there are many ways to produce ethanol and more than one way to make cellulosic ethanol.
Cheers.
I suggest some references to see that another feedstock are possible to make ethanol, for example :
http://www.bluefireethanol.com/technology.htm
http://www.brienergy.com/pages/resources01.html
I can suggest a lot of projects which are studying celluslosic ethanol from wastes if you are interested.
Xatt from Barcelona
As mentioned in another reply, my comment was not meant to suggest that there are not other routes. Only that "gasoline" already exists as a cut from the distillation of crude oil.
In the Four Corners region of New Mexico, you can pump oil out of the ground, run it through a distillation column, take the gasoline "cut", distill it a little more to clean it up, and put it into your gas tank and it will run most spark ignited internal combustion engines (ICEs). The octane rating sucks, but at 6,000+ feet above sea level anything above an octane rating of 78 is pretty much a waste (unless you really do have a gasoline guzzling high performance engine). You couldn't burn it sea-level.
The Blue Fire link, very much mirrors the description I gave. Note that converting the cellolose to glucose is one additional step beyond what is used in acid-sulfite pulp and paper mills. If you've ever used vanillin (artificial vanilla), one source is the acid sulfite digestion of cellulosic materials that ultimately ends up as paper and other cellulose materials. The chemistry of cellulose -> glucose -> EtOH and CO2 is fairly basic. Getting it to go that way with acceptable yields is the issue.
As for the other "sources" for conversion, as mentioned elsewhere, you eventually have to end up with enough energy and the right mass ratio to produce a liquid that is 52.17% carbon, 13.04% hydrogen, and 34.79% oxygen. Otherwise you do not have EtOH.
My point was that "gasoline" already exists in solution with crude oil and it's a matter of distillation to recover at least the first cut. A small portion of the heat content of the oil is all that's needed to start and sustain the process. Additional chemical processing steps (that require more energy) can be used to increase the yield of components that make up gasoline.
One cannot argue that "ethanol" already exists in solution with any of these other feedstocks (not even crude oil). You might have carbon, hydrogen, and oxygen to be able to tease out ethanol through a number of chemical reaction steps. As for cellulose, when one looks at the structure, it's pretty easy to see why "wood alcohol" is a result of fermentation of cellulosic materials.
This does not deny that there are other approaches such as gasification and the various synthesis reactions from "simpler" compounds that can be put forward. In the end, you must balance the mass and energy equations so that you end up with a liquid that is 52.17% carbon, 13.04% hydrogen, and 34.79% oxygen.
But to throw in one pound of dry, ash-free, sulfur and nitrogen-free coal with a HHV of 14925 BTUs and have it yield 18,656 BTU (or the equivalent of 1.42 pounds of ethanol) as suggested by the 1 BTU of coal=1.25 BTU of ethanol just does not work.
In theory, a typical low sulfur coal (after processing away sulfur, nitrogen and ash) would have enough oxygen (the limiting factor) to produce about 0.3 pounds of EtOH. Obviously you could use the left over carbon and hydrogen in a standard reduction reaction with water to produce syngas for addition reaction. However, this is mass (and energy) that the 1 BTU coal = 1.25 BTU of EtOH, mentioned above,ignores.
Gasifying biomass for syngas puts you in a better chemical balance for EtOH production (C/H/O ratios) but it does not solve the energy balance problem (since you gasification step requires energy from somewhere) and the demand that various shift reactions require to work properly. For example, you would not want to produce acetaldehyde instead of EtOH.
It may be debatable whether it's "better livng" or not, but it certainly is and would be living through chemistry.
Both scenarios eliminate the energy balance problem you highlight.
Still, one must also balance the chemical equations and neither of us can do anything to change that.
As for landfill gas, it contains (as do most anaerobically derived gases) a signifcant proportion of CO2 (we typically see around 40% from our landfills and various other anaerobic digesters). And the system(s) to extract the LFG must be designed to accomodate varying flow rates over the life of the landfill cells while maintaining anaerobic conditions within the cell. Separating the CO2 from the methane (and other contaminants) is an important step for any further shift reaction that may be contemplated. Many the LFG projects projects use the gas as fuel for something else (say to "run" a gasifier).
There is one anaerobic digester project I am familiar with that is using the biogas (from pig manure) to create methanol. It's working (not necessarily working well) and the methanol is used elsewhere in the production of a biodiesel product.
As for MSW gasification, we could do that with the same limitations that current MSW mass-burn or RDF facilties face to get the "fuel" to remain in a satisfactory operating range. The second law of thermodynamics gives us some insight into the energy costs associated with that "fuel mixture."
Bu, at fact making ethanol from wastes (they could be MSW, which are thrown to a landfill, or crop which are burned or thrown) is to live in a bit more sustainable world. So, if the process is ecomically viable (we must not forget that money move the world), Could the energetic efficiency be our first objective? In the energetic balance, BTU inputs of biomass are count, if it is thrown to the landfill?
Technological progress and efficiency have mostly come about because we have had an energy reserve to make the next transition. Unfortunately, we don't often see the the initial energy costs associated with that transition. An example of this is in the PV solar cell arena. But that's a whole separate discussion.
Much of the point of the discussion, of course, is how self-sustainable these alternative processes really are as an alternative to oil. If biomass or other derivatives of past wastes really had to sustain themselves independent of other finite resources, we might find that it realy does take 5-10 BTU (or KJ) of biomass to create 1 BTU (or KJ) of usable ETOH. That a portion is lost as a result of chemical reactions required to get a usable product and/or as energy to drive the process.
In that case, you must have enough biomass and enough land to keep producing biomass at an adequate rate. We might find this tradeoff acceptable. But the correct way of looking at it is that there is, for example, 6 KJ of energy total and it's going to take 5 of them to leave us with 1 KJ to do something else.
What you are doing is moving the starting point to the refinery, where 1 BTU in gets you 0.8 BTUs out, but that's only the back-end of the calculation and so not a true comparison with the energy return on ethanol production. Now, start at the beginning with ethanol - no plant, no energy expended. At the end of the chain (after planting the seed, tending the crop, harvesting and converting), you get 1.25 BTUs of ethanol but have expended 1 BTU of energy getting there (if Argonne's figures are accurate). Starting at the beginning with oil, you end up with 4 BTUs (or more, for most conventional oil) for that 1 BTU expended.
Is that any clearer, Jack? As RR said, some people compare apples and oranges, which is what you've been doing in your posts. When you compare apples and apples, the picture (hopefully) becomes clear.
Tony
your converted and consumed argument is false
arguing that all energy is converted is the same as consumed is wrong
it is more helpful to think in terms that the resulting energy in the gasoline remains "untouched" in a "potential state" throughout the process
your use of energy is never lost and appeal to the laws of thermodynamics is a misunderstanding on the nature of stored energy available in the present .. not to mention a misuse of terms.
if your reasoning was correct no process of acquiring energy density for any end user use would be inefficient in practical terms
HTH
Boris
London
From the site
http://bioenergy.ornl.gov/papers/misc/biochar_factsheet.html
We see that oil has approximately 2.5x the raw energy content of switchgrass or sugarcane. So if we 'find' a tonne of oil, ignoring the cost of discovery and extraction for the moment, we will be 2.5 times better off at this stage of the energy 'creation' process than if we 'find' a tonne of switchgrass. Then, for each 'finding' process we need to calculate the energy input. For oil it is primarily exploration and extraction (yes, getting higher all the time but try to grasp the EROEI of an oil well spouting 5000 bbl/day of crude oil). For cellulosic biomass it is planting, irrigation, harvesting. Only then do you get to the refining step that is being talked about with the oil/gasoline and corn/ethanol. I haven't done figures on these, but I strongly suspect that by the time you get to the refining step, oil is more than 2.5x ahead of the biomass in terms of energy content and that the ratio becomes even more skewed after that.
It is just hard for me to understand how anyone can conceive the notion that energy 'creation' via ethanol can be more efficient than energy 'creation' via crude oil. Unfortunately it is a dead horse that some influential people seem to think is still alive and kicking.
Please see my post above for Trooper RE: there are many ways to make ethanol and more than one way to make cellulosic ethanol.
Situation before, must assumed equal for both cases.
One BTU Biomass
One BTU crude in ground
One BTU Coal in ground
Zero BTU transportation fuel.
Raw energy before: 3 BTU
--------------------
Ethanol, after:
Zero BTU Biomass
One BTU crude in ground
Zero BTU coal in ground
1.25 BTU ethanol in car
Raw energy after: 2.25 BTU. Processing loss = 0.75 BTU
Fuel gain: 1.25 BTU
Processing loss / Fuel gain = 0.75 / 1.25 BTU = 0.5
----------------------------
Gasoline, After:
One BTU Biomass
Zero BTU crude in ground
One BTU coal in ground
0.8 BTU gasoline in car
Raw energy After: 2.8 BTU. Processing loss 0.2 BTU
Processing loss / Fuel gain = 0.2 / 0.8 = 0.25
I suspect that the human labor in making one BTU of coal plus one BTU of biomass is larger than that making one BTU of gasoline.
There is an energy disadvantage for ethanol, except for the critical fact that we will be depleting crude faster than coal, and the cost in energy and labor to extract the next barrel of crude will be increasing with time.
Ethanol:
Start with one BTU of coal
End up with 0 units of coal and 1.25 BTUs in the form of ethanol
Gasoline:
Start with one BTU of oil
End up with 0 BTUs of oil and .8 BTUs in the form of gasoline"
Jack;
Here's the problem I see with your summary above. (regardless of what form the original btu's are coming in)
That One, original BTU of 'fuel' is not heading into the refinery, but running the Oilfields, at which point, it gives us some 10 BTUs of oil from the ground (assuming the 10:1 EROEI of crudeoil production), THEN, you take that to the refinery with it's 80% yield, and end up with 8:1, as opposed to Ethanol's 1.2:1. This is why the '.8 efficiency' of the gas refining process cannot be evaluated without the original input of drilling, pumping and shipping the crude, which carries all the 'energy profits' of the deal.
(I hope I got the numbers reasonably close, but I think the concept is sound)
Bob Fiske
But why does an oil refinery have a greater claim on raw materials than an ethanol refinery? Why does one use "original energy" and the other doesn't?
At the end of the day, I think this discussion is silly and close to meaningless. Trying to compare these things head to head requires so many simplifying assumptions that you can steer it where ever you want. I see Robert's arguument with Wang, etc. as a fight over whose assumptions are right. I see why Wang backed out. I am sure he has better things to do.
I don't think corn-based ethanol is a viable solution. I have mentioned elsewhere that it is a pure subsidy play and folly for the US.
By the way, the World Resources Institute/German government study below lays this out a bit in terms of energy efficiency and energy balance (see page 16)
http://www.worldwatch.org/node/4078
Again, this discussion is energy balance trivia and we are not getting anywhere, so I will sign off on this topic now. Other parts of this thread are more productive.
That's where you are wrong. It's a fight over whether I will allow the country to be led down the wrong path based on false arguments, when we should be directing our resources elsewhere. To assume this is just some turf war tells me you don't quite get it.
However the fixation over whether one method of calculating an equation is gospel and the other a fraud is certainly turf war like. The emotional arguments against me in this thread underline that.
People rage against ethanol subsidies, are fine when they are directed towards wind or solar. They insist that ethanol plants must be run as a closed loop with ethanol alone, but don't apply that to any other technology. Have you ever heard someone say a solar cell factory must only use solar energy as an input? They say I am willfully distorting facts to support corn-based ethanol, when I have clearly stated over and over that I do not.
Robert, I commend you for you efforts to bring light to the ethanol debate. However, I wish you were as rigorous with your facts as you demand others to be with theirs. But if your war is righteous, this little battle is trivial at best and a losing distraction in reality. Wang may be midleading the public by drawing their attention to a meaningless statistic. In a multi-step process, it doesn't avail us to look only at one step. However, I do not think that on this one minute, trivial issue he is wrong.
Wang is an ethanol boosetr, Pimentel an enemy. But let's listen to their arguments and not dismiss one or the other on anything but the facts.
A specific example is always preferable to painting with a broad brush.
However the fixation over whether one method of calculating an equation is gospel and the other a fraud is certainly turf war like.
That's not it. It is about rebutting a specific argument that ethanol proponents often use. And the incredible part is that some people here still don't seem to get it, although most do. It is not about calculating via one method versus another. It is about whether it is more efficient to use BTUs to produce gasoline or ethanol. That's a no-brainer, it's not even close, and yet ethanol proponents claim exactly the opposite of reality.
In calculating Return on Investment in finance, practitioners often disaggregate the process using a Dupont analysis. In that case also, one could point to a single ratio out of five and claim that it shows a business is profitable. For example a company with huge debt would have a very high financial leverage and on this measure alone could look better than another company.
In reality, there are problems associated with high debt levels and debt alone does not a business make. This is the error that I see Wang committing. I think his point is useful, but it does not justify grain-based ethanol production.
I regret getting involved in this discussion, but I am about 70% as stubborn as you are and so neither of us can withdraw. In the greater scheme of things, I don't think we disagree on any of the crucial elements of the merits of grain-based ethanol.
I have pointed this out on numerous occasions.
Insisting that your method of calculating it is inviolable and theirs worthless is a distraction.
It's not worthless, if comparing apples to oranges is your thing. I prefer my metrics to be consistent. In your analogy on finance, I have no problem with that if we compare the next business in exactly the same manner. The problem comes when we compare Business A with one ratio and Business B with another. It's like looking at the gross for one business, and claiming that since it's higher than the net for the second busines, that the first business is better. There's your relevant analogy.
They start with a post production energy source be it crude oil, coal, or natural gas and wind up with a liquid fuel, ethanol or gasoline.
The apples and oranges aspects I see are that coal and NG are useful as they are and crude oil is not. Crude needs to be refined to be useful while coal and NG don't. Also natural gas has actually already undergone some refining.
Again, I don't think you are wrong in pointing out that this metric on its own does not mean much. However, it is a legitimate way of showing that conversions of energy to other forms has costs.
On its own, a 1:1.2 energy balance for ethanol is not a death sentence. The fact that it has such a high cost that is needs to be permanently subsidized and has so many damaging externalities is.
Reading what you wrote and trying to understand what you were meaning and assuming you were able to understand some of the scientific argument being talked here, I came up with an idea.
I think the main problem is only a pedagogy problem, I do think that if you are having some difficulties in understanding what we try to explain to you, there can be only 2 explanations.
- You are not able to understand the difference in metrics.
- We are not able to explain to you and to others in a meaningful way the metrics.
Let's assume that we are just too bad pedagogue and that we need to put it more elegantly.Here is a graph of the yield of ethanol vs the yield of gasoline.
Notice the use of the word energy, I did it on purpose so to not let you mislead by energy container (in the form of ethanol, coal, oil, etc).
What the ethanol is made from and what kind of energy is used is irrelevant here. Here I assume that the eroei is positive.
For the ethanol, we spend 1 BTU to get back 1,23 BTU. Efficiency in the process is irrelevant. Notice here that the increase in BTU available need to take into account the left over that will be used as feed for cattle (hog can't digest it). That part of the equation is available for the cattle but certainly not for you car :).
Because you love so much the 80% efficiency, I have put were it does apply in the oil to gasoline process. It applies when you are refining the crude to gasoline.
Heading out has writen a lot about refining processes and how some of the oil extracted is used in the process to actualy transform the crude into different usable products. Notice that crude not only produce gasoline but also a slew of products.
The laws of thermodynamics also tell us that no process is more than 100% efficient, heck a whole lot are less than 80%.
I realy do hope that this little figure can remove much of the mysteries in the different argument debated here.
For ethanol, you are just looking at the refining stage, while for oil, you are combining two stages: production and refining.
This explanation seems to be the clearest one.
http://www.theoildrum.com/story/2006/8/25/221617/881#236
I think the problem is:
3. The metrics are inconsistent (or at least the processes aren't parallel, so that what you are comparing is two different things)
Energy Return On Energy Invested.
It is not a mysterious or a magical thing. It's only a concept of physics. Physics dont care about boundaries that you put artificialy. When you look at the sytem, you have to look it at whole.
For ethanol, I do include the farming and the capital cost.
You do have to grow any kind of biomass.
You also have to build plants, use machinery (otherwire used for something else) thus the capital cost. Building machinery and plants use energy like any process use energy.
Then you take the biomass and transform it into ethanol, using heat produced either by coal or natural gas.
Energy invested is the sum of :
farming energy requierements + capital + distillation
Energy return is the sum of :
ethanol + distiller grain
For making gasoline, you do know that it takes crude oil? Crude oil is already formed, was formed millions years ago. We are mining this form of energy. We do not produce crude oil. Think about it, no one produce oil. We only extract it.
You then have to take into account the pumping and transport of crude up to a refinery. Then you use some of the energy content available in the crude to power the process.
Energy invested is the sum of :
Finding + extracting + transporting + refining + distributing
Energy return is the sum of :
energy content of all petroleum product produced.
That's why I made you this graph, so you could understand that
EROEI is not efficiency
Like speed is not acceleration. Like time is not a distance.
Because a small background in science is needed to talk about scientific issue, I assume that you are able to notice the difference every one tries to teach you in this thread.
What in those fairly easy concept of eroei you do not understand. Please forget about the ethanol issue, I want to know what could make you understand the difference between efficiency and EROEI.
Can you help me making you this clearer?
"OK, so I have 100 BTUs of oil. I divide it into 2 lots of 50 BTUs.
In the first case I refine it to gasoline and end up with 40 BTUs of gasoline.
In the second case I use it to make fertilzers, pesticides, diesel for the tractor, etc, grow some sugar crop, ferment it, distill it and end up with 67.5 BTUs of ethanol.
What am I missing here? "
It is not a matter of science. It is logic and economics. You have resources in the form of coal, oil, natural gas and biomass. You want to convert them to useful products.
Try to keep them in these categories and maybe you will be able to understand.
It is flawed from the start.
Go see the reply.
That is the most you can argue for. Large amounts of ethanol can't be produced without fossil fuels, but large amounts of gasoline can be produced without ethanol. In this regard, ethanol is a loser, as well as contributing to damaging crop land and depleting fresh water.
If you don't support ethanol, then why continue with the false arguments that you have? The valid comparison is full lifecycle comparison, not comparing partial lifecycle with full lifecycle. And the lifecycle should also be practical (i.e. all of the fossil fuels could not practically be converted to ethanol).
Tony
I refer you to Vinod Khosla's text which you can find there. Here you can read about USA resources of biomass.
Xatt
Tony
Actually, his analysis was correct. He considered the BTU inputs and outputs for the entire process. The level of confusion over this issue has been surprising to me. The problem is straightforward.
I can treat BTUs as an investment. Where can I invest my BTUs so that I end up with the highest BTU return? If I invest 1 into ethanol production, I end up with 1.3 BTUs. If I invest the BTU into oil and gas, I end up with 4-5 BTUs of gasoline, diesel, etc.
Or, let's say my objective is to make 1 BTU of liquid fuel. Will I burn up more fossil fuel energy in making ethanol, or in making gasoline? Again, I will burn up 3-4 times the fossil fuel energy in making 1 net BTU of ethanol as opposed to 1 net BTU of gasoline.
That's it for my contribution today. This consumed far too much of my day yesterday, and I am working 12 hour days this week as it is.
I will have to come with a better graphic that could show complete process (somewhat complete) so the lay man can understand it easily.
Thanks for the commentary :)
The energy balances of wind and solar far exceed that of ethanol. Plus, as far as I know, the government wind subsidy has had to have been renewed yearly since its inception, not allowing wind development companies long range planning benefits.
In Brazil, ethanol operated with minimal government support and is unsubsidized.
I would gladly support a shift that would provide balanced subsidies to all technologies (partially as a carbon tax) that would provide an equal footing for all. I suspect in this context grain-based ethanol would not thrive, but sugar would.
I applaud your stance on showing the truth.
As a Chem Engr, I am appalled that they are trying to portray those number jumbles as science.
It is a sleigh of hand trick that any 19 yr old engineering student should be able to catch.
The sad thing is that I fear that 99% of the non-technical community will only hear "Ethanol will save the day. The fuel prices will be back to 1998 levels soon enough."
I'm not sure what you mean by this. What claim? The energy inputs required in getting oil from the ground to your tank as gasoline are economical simply because of the great positive ratio (once far greater) of Energy gained from pumping it out of the ground. The costs of pumping and refining it are not yet bad enough to make the process obsolete. It sure sounds like Ethanol (from Corn) is so marginally positive as to be unworthwhile.
What is the Original Energy?
I don't count the Rain or Sunlight that fuels the Corn's growth, any more than I count the years, pressure or heat that may have been responsible for making that hi-protien crude. But for both processes, I think we should count all that we have to expend to get either one out of the ground and into the tank. Unless you mean by original energy that Ethanol is only considered justified if it can be made with more ethanol, and not a petrol byproduct..
Sorry if you feel like the target today, Jack. I don't agree with some of your position on this, but I didn't write anything intending sarcasm or personal attacks. Hope none of it came off that way. I appreciate your standing your ground, and I know you're only here like any of us, trying to figure out where to go with a huge set of challenges.
Regards,
Bob Fiske
You say "The energy inputs required in getting oil from the ground to your tank as gasoline are economical simply because of the great positive ratio (once far greater) of Energy gained from pumping it out of the ground."
Couldn't you also say that "The energy inputs required in getting <<coal, natural gas and biomass>> from the ground to your tank as << a gasoline substitute>> are economical simply because of the great positive ratio (once far greater) of Energy gained from <<digging and>> pumping it out of the ground."?
If we were comparing CTL to oil production, surely you would start with both in the ground. My claim is that this has to apply equally to all processes including ethanol production.
However, I admit that you can no longer reasonably call the process "renewable" and perhaps it should not be called grain-based, but rather grain, coal and natural gas based ethanol production.
Hi Jack;
I do agree that the energy benefits of the oil's extraction from the ground count for both if they count for either. I guess I see ethanol as simply 'making Toast by retoasting toast', instead of making it from bread. In other words, the crude is already getting refined into transp fuels to run the farms, the NG is already usable in its extracted state as a fuel source before you apply it to this additional process. The 1.3:1 margin, (if it is that much) would be great on my MoneyMarket account, but it is hardly enough 'value added' to justify this elaborate process, only to end up at about where you were beforehand. I don't think it works to look at that pinch of positive EROEI in comparison to interest or investment yields. Energy can be compared in some ways to money, but I don't think that comparison works.
It's not like you're making $130/week and your expenses are the $100, the last $30 being available for savings or reinvestment. It's more as if it costs you that $100 just to have that job (your commute?).. and the rest is what you have to live on. It's the net energy profit that makes it worthwhile or not.. the fuel consumed to get it there is just 'the cost of doing business'
Food energy has a pretty marginal EROEI, but the process of working to get it is also beneficial to People and Animals. Our bodies need to do that work in one form or another to stay healthy, and the natural systems have developed to maximize the work we get out of every calorie.
http://www.theoildrum.com/story/2006/8/25/221617/881#236
This is the crux of your problem understanding this. In the case of gasoline, you have not burned or used up that original gallon of oil to get that gasoline. You have only used up part of the oil to the get the gasoline. Think of it as wastage.
In the case of ethanol, the fossil fuel inputs are completely burned up in the process of getting the ethanol.
Politicians misuse data and arguments all the time. Let them get away with it for too long and it becomes impossible to set the train back on the track.
EXACTLY! Because a wrong argument backed by authority wins conviction among all the misinformed or plain stupid.
Alas, there are so many more wrong arguments than right arguments that it is a work of Sisyphus to "challenge all the common arguments".
I don't think ethanol will ever provide more than 10% of current consumption. I also don't think it is a permanent solution as electricity seem to be a better bet for the long term. However, ethanol, particularly produced by sugar cane in warm climates does make sense within this context.
The IEA says that the Europe could produce 5% of current liquid fuel with 20% of current agricultural land. For the US it would be 21%. If agricultural land expanded a bit (maybe back to levels where it was 10 years ago) and production became for efficient, this could have little impact. I am sure that converting farm land to beef or pork is more wasteful in terms of land, chemicals and environmental impacts.
From a business tandpoint (Vinod) 10% of the global oil market is a business bigger than Exxon. From a energy security aspect 10% is a big step in the right direction.
However, most importantly, from a climate perspective, ethanol is a huge positive. Click on any of the studies I have linked to in my earlier comment. These are easy to find and very well documented.
If you are worried about people eating, climate change, animal meat, and loss of farm land to non-agricultural activities are a far greater threat than 10% of fuel from ethanol.
From the USDA:
http://www.ers.usda.gov/Briefing/LandUse/majorlandusechapter.htm
Cropland, 442 million acres (20 percent of the land area)
We plant all of the US cropland to corn. 100%
1 bushel of corn yields 2.5 gallons of ethanol. USDA
1 acre yields 160 bushels. (All-time record in 2004.)
1 acre yields 400 gallons of ethanol (2.5 × 160).
One gallon net takes 3 to produce EROEI 1.34 to 1
400/4 = 100
442 million acres x 100 = 44.2 billion gallons net return
Ethanol has less energy density 44.2/1.5 = 29.5 billion gallons net ethanol
We use 144 billion gallons of gasoline per year
29.5 is 19% of 157 billion demand.
You just (willingly?) keep muddling the issue.
Even if we were to produce that 10% in Ethanol you mentioned before, it would still involve devoting about another 8.4% of another form of fossil fuel to create it, given the 1.2 EROEI. THAT's why this ROI argument keeps coming back. If 10 out of every 100 gallons of our transportation fuel was Ethanol, we would only be getting 1.6 gallons of 'new' fuel in the deal, and that would also come to us with a heavy price in water-use, land use (over-use, really), and human labor, too.
If your ATM charged even 20% of your withdrawal amount, you'd quickly see the return was not worth the effort. That would be a 4:1 EROEI, right? (If you counted Money as Energy) You'd say 'There has to be a better way'.. which is what I believe RR is saying about ethanol, which charges 84% of your total withdrawal for the benefit of some 16% back in pocket-change.
Instead of banking on a 'Steady Climate-dependant' energy source, why not put that energy into capturing Wind, which looks like it might be plentiful in a time of growing weather 'events'.. Take the lemons of future Hurricanes, and make Lemonade.
If it also required you to put in water and environmnetal costs that exceeded $.24, you would not do it. I think this represents the ethanol case.
With oil and gasoline rigth now you invest 1$ for getting 8$
30 or 40 years ago, it was 1$ investing for 35$ investing.
Replace dollars with btu and you get the picture.
Please go visit eroei concept introduction.
This is a fairly basic concept that I learned about just days or weeks after finding about peak oil. Eroei is very well understood by all the people trying to counter your arguments.
Notice that you will not find anything about ethanol in that website. What they are interested here is Energy Returned On Energy Invested.
It's also interesting to note that in the example you gave, you invest 1 BTU to get somewhat 1 BTU of ethanol and a small amount of low quality grain that you can only give to the cattle. I dont think we can run your car on ethanol/cow powering system :).
I looked at your link and agree it is fairly basic. It says you start with extraction. So why are you starting with post-extraction BTU inputs for ethanol, but not for gasoline.
I think you are drawing the boundaries in two different places in your comparison. Look at the link I posted in response to your helpful diagram above.
BTU inputs for ethanol include growing + capital cost + distilling.
BTU inputs for gasoline include extracting + capital cost + refining.
The energy system does not care about boundaries you want to put. No real boundaries exist in the physical domain. Every kind of energy needs energy in order to get it.
Forget the ethanol, it's not a matter of ethanol or boundaries. It's a matter of two different metrics.
Can you make the difference between efficiency and EROEI?
Please tell me you do and explain me how it is different. Try not to use ethanol of crude oil processing if it confuse you.
BTU inputs for crude oil include extraction.
BTU inputs for ethanol include coal.
BTU inputs for CTL include coal.
BTU inputs for coal include extraction.
Producing coal or crude is one step. making it into a liquid vehicle fuel is a second step.
I am now officially giving up. This entire discussion is silly and meaningless. It all revolves around where you draw the lines and pretending that there are equivalent apples to compare in two different processes.
You can simplify this enough to do a cute little chemistry 101 exam question, but that doesn't mean it is right.
You need biomass (any) to get ethanol.
When computing EROEI of ethanol, the growing part is included in the calculation, not just the actual distilling.
Like when you compute EROEI of gasoline, you need to start from the crude oil extraction because that's really when you use the initial energy.
System 1
You use a small amount of energy (1 unit) to get a big amount of energy (10 times the initial amount) and then you process it for actual use in the car at 80% efficiency, getting 8 energy unit.
EROEI 8:1
System 2
You use a small amount of energy (1 unit) to get some biomass feedstock (giving 1,40 unit) and then you process it for actual use in the car at 90% efficiency, getting 1,26 energy unit.
EROEI 1,26:1
Efficiency of processing a form of energy into an another cannot exceed 100%. It is forbiden by the laws of thermodynamics. Thus while you want to compare two things, you need to compare things that are comparable. I gave a better (theorical) efficiency for processing the biomass into ethanol but still the whole process only added 0,26 unit of energy.
That the ethanol production is a positive or a negative return is irrelevant here. What you need to grasp is that the energy invested in the system for making gasoline is a small part of what is returned as usable energy.
That's precisely that high EROEI that enabled the developpement of our society.
If the crude oil to gasoline process would have yield lower increment in the available energy, it would not have been as profitable and it would not have been developped as a form of energy. Maybe it would have been used only for chemistry purpose.
Trying to remove the high yield of crude oil to gasoline process is like trying to judge if tasty tatters would be a great source of energy for making ethanol. If you start with the tasty tatters as the raw source of energy, you know it's flawed from the start. Because you need to take into account every steps of growing potatoes, manufacturing and transport in the overall EROEI computation.
When I was young, some old people talked about a flour mine, but I could not find it. I guess that tasty tates mines are as difficult to find :).
Comparing one refining process with the other's extraction and refining process is neither consistent or useful.
I do understand where you are coming from. In ethanol, you only count corn as the source of energy that should be credited with a lifecycle perspective. Coal and natural gas are inputs that are counted at their BTU values.
For gasoline, you count oil as the source of energy and crediot it with the full lifecycle cost. You refining equation counts electricity as an input and charges it to the equation at BTU value.
However, if you have to view the two processes from a lifecycle perspective, which I have agreed makes sense, you have to credit all of the major inputs from a lifecycle perspective. So, I shift coal and natural gas in the ethanol equation into the source category and credit them with extraction EROEI as well. If these account for a greater portion of the energy input than biomass, they are raw materials as much as the biomass is.
So there are two legitimate options. The one I linked to that starts with 50 BTUs at the start of the liquid production process, or one that starts with 50 BTUs at the extraction process for BOTH gasoline and ethanol.
Gasoline
- 50 Btus of input produces X amount of oil
- This is converted at a rate of 1:.8
- or -Ethanol
- 50 BYUs of input produces X amount of coal, natural gas and biomass.
- This is converted at a rate of 1:1.2
I also agree that the high EROEI of oil is what has made it useful to society. However, this also applies to coal and natural gas.The death sentence of ethanol is related to high operating expenses, environmental damage, inferiority of ethanol as a gasoline substitute, resource extraction, etc. Not a poor balance in converting coal, gas and biomass to liquid fuel.
The above affirmations are misleading at many accounts.
1st
Energy is never created, it is just transformed
2nd
When converting a form of energy into an another form always incurr in loss of energy.
- BTUs to convert oil into gasoline is already in the crude oil, thus the 80% efficiency.
- It is not a EROEI rate, it is an efficiency rate.
- You have to start from the extraction.
- Actual EROEI was 1:100 at the dawn of the oil age, 1:35 30 years ago and still 1:8 up now.
EROEI computed for all inputs (capital+energy for getting gasoline.For getting 8 unit of gasoline energy, you need only 1 unit of energy.
2nd
For Ethanol
- BTUs used comes from coal, nat gas, oil, biomass
- BTUs yield is in the form of ethanol and distiller grain but ONLY the ethanol is useful energy.
- Computed EROEI of 1:1.2 include all the inputs for growing any biomass (wether it is corn, algae, or other) the inputs in coal and/or nat gas for distilling and include in outputs the distiller grain.
In both cases capital expenditures for making the processins plants, harvesters, pipeline, etc are calculated.I did not compute myself the EROEI for Ethanol, I only used the number stated in this thread, actual EROEI is a disputed thing.
If the EROEI would be higher, say 1:5, there would be no need for subsides and expenses would be compensated by the great positive yield.
My point remains accurate and uncontested. Your are crediting gasoline with BTUs already in oil, but are not giving the same credit to the coal and gas inputs to ethanol.
I presume you would do the second. Then why won't you for ethanol production. Your measures are inconsistent.
Energy is needed to get coal from the ground (can you figure that?)
Energy is used in the process to get liquid fuel from coal. That energy comes from the coal, part of the coal used to make the actual liquid fuel.
Say you extract 100 BTU of coal, you need lets say 20 BTU. After processing the 100 BTU extracted, the yield is 60 BTU, (60% efficiency)
So you get
extraction
input 20 BTU (including capital cost)
output 100 BTU
transformation
input 40 BTU (From the coal, not from an external source)
output 60 BTU
So the EROIE is 1:3 where you get 3 unit of net energy from investing 1 unit in extracting the coal.
The same goes for shale bitumen or tar sands.
For ethanol, it is the same thing also. Below numbers are hypothetical, used for demonstration purpose only.
Extraction of coal
input 10 BTU
output 50 BTU
Extraction of nat gas
input 10 BTU
output 50 BTU
Growing of biomass (including capital cost)
input 80 BTU
output 0 BTU (BTU not accessible whitout transformation)
Thus you invest 100 BTU to get 100 BTU raw
Transformation
input 100 BTU
output 120 BTU
You have in input the coal, the nat gas and the biomass (we are really simplifying here) amounting to 100 BTU (initial energy investment) The energy contained in the coal and the Nat gas is used to transform the grain into ethanol. The ethanol produced yield 120 BTU.
Thus an EROEI of 1:1,20
For calculating an EROEI, extraction and the imbeded energy content need to be taken into account.
So what you just bring is not a matter of choice, it is a matter of what is done and how it is computed right now. This is not like buisiness books where you know what's in and what's out. The boundaries of a company are well defined but the boundaries of an energy system just are not.
You have set up your hypothetical numbers to match the EROEI of ethanol, but in reality the balance is much better. The EROEI calculation for ethanol is only at the point of conversion. If you accept a more positive extraction ratio, the total EROEI will be much higher.
But yeah, the whole system need to be taken into account
Well, I have to leave for a meeting now :)
If you agree to the laws of thermodynamics, please state what if the Efficiency rate for ethanol conversion. This number NEED to be under 1 (i.e a percentage below 100%)
Well, as for the uncontestability of you argument, you are sliping I dont know where. Trying to remove the energy imbeded in oil in order to process it into gasoline is complete giberish. The energy in oil is USED as we speak when refining crude into gasoline (and many other products)
The part of the distillate is used to heat the crude oil, in order to refine it.
For ethanol, you need 1 BTU unit (wether it comes from coal, or nat gas, electricity, anything) to get ONLY 1,2 unit of liquid fuel.
The EROEI number of 1:1.2 is different (by it's own nature) than the 80% efficiency in the refining process. EROIE for oil is 1:8 (for heavier kinds of crude)
The only purpose of subsides, tax break, incentive are to compensate for the very low yield of ethanol. Ethanol will die as the hydrogen car has died and it will die has peak oil will only come by and confirm that when oil prices increase, cost for ethanol increase accordingly.
As I stated from the begining, you try to compare 2 different units of measurements. You are trying to measure time using a sliding gauge. Have fun while you try it, I will still put my time debating with more scientific litterate people.
My students learned stuff much more harder to grasp.
Ethanol is Brazil has been produced for thirty years and production is increasing. The fossil inputs to it are very small. Face facts, it works. Maybe one of your students can explain it to you.
Good luck in your debates with smarter people. You backed down and accepted that the process has to incluse extraction costs in both cases after I explained it to you several times. If you hadn't rigged the numbers, you would see that the balance from this standpoint is greater than 1:1.2. The reason is energy in the biomass, not violation of the laws of thermodynamics.
Who knows. I'm guessing he'll want a rematch. Let's go get a burger.
We cannot do anything to open you mind but we will keep trying anyway.
We start with 1 BTU (doesnt matter where it comes from)
1. Ethanol
ERoEI = 1:1,2
we need biomass to get ethanol, so we have to include growing. The process include any input in energy to distillate the ethanol.
1 BTU -> growing, process, etc -> 1,2 BTU
1,2 BTU -> growing, process, etc -> 1,44 BTU
1,44 BTU -> growing, process, etc -> 1,728 BTU
1,728 BTU -> growing, process, etc -> 2,07 BTU
2 Gasoline
ERoEI = 1:8
We need crude to get gasoline, I mean we need that RAW material which per itself contain energy. Refining include any use of energy to get it into gasoline (and diesel, naphta, propane, asphalt, plastic, etc.)
1 BTU -> extracting, refining, etc -> 8 BTU
8 BTU -> extracting, refining, etc -> 64 BTU
64 BTU -> extracting, refining, etc -> 512 BTU
512 BTU -> extracting, refining, etc -> 4096 BTU
If we want to use the first cycle to get gasoline, than the second to get ethanol, like you and Base are trying to cope with here is the result :
1 BTU -> extracting, refining, etc -> 8 BTU
8 BTU -> growing, processing, etc -> 9,6 BTU
and I do think that 9,6 < 64 (being well advanced in math, say more than second year primary)
Say you are a company (you know, for making money) where the do you want to invest your BTU?
Ethanol, getting 1,2 BTU
or
Gasoline, getting 8 BTU
I dont see in anyway how could any company chose the former. Except if grower has lots of subsides, use diesel powered machines, the processer has also tax break or something else. Maybe then, they can cut a small profit. Otherwise, I just dont see it happenning.
I still dont see how can someone sane in the brain can tell that 1,2 is better than 8. I still dont know how can you and base that it is better than 8.
Maybe you have to take apples, get 1 apple and a slice in one side. Then on the other side take 8 apples. You can throw in a balance if you are not confident that 8 apples are more than you 1 and a slice apple.
In fact that may be one of the solution.
What I was trying to state here, is the fact that gasoline as a better ERoEI than ethanol.
I do think that we need a fuel replacement but I dont think that ethanol will make it. In anyway, I'm sure that they will try to make it work up to realising that when the oil will cost more and more, ethanol will cost more and more.
The Car is a species on the verge of extinction.
And I mean anycar.
I still use mine, and will do so, up until I cant afford it.
What is making sense is trying to make an other living arrangement. There is only two way towards it. Either we go ther on our own or we will anyway.
So as for the question of wether ethanol is better than gasoline, I think I made my point. It is better, while we can, to produce gasoline than it is to produce ethanol.
Ethanol may be a good product, it may even result in a small increase in the energy system. What Robert and I are saying is that the amount of energy added is marginal compared to crude oil and gasoline.
The only reason why we were able to get the society where it is right now, it's because oil contain lots of energy. The low content of energy in ethanol and the high energy investment needed to produce it will not allow us to go on the way we live now.
I just found a good comparison in the way we eat.
Say you want to eat and what is available to you is a good steak or a bunch of edible tree mushrooms.
The steak contain lots of energy, it is more concentrated than the muchrooms.
To get the steak you have expended some kind of energy (hunting for it, in this example) but the energy you will get from it is high. You will then be able to do something else with your time, having needed only a fraction of the meat energy to get more meat.
On the other way you have the edible tree mushrooms. I have eated some while a was a boy scout. Yes, they can be edible but to state one of my friend, they are untasty. Just to collect a bunch for a meal will take you 2-3 hours. Eating them is hard, you have to chew really long and it taste like wooden flour. The digestive system in your body will take lots of energy to digest it. When you have finished, you are allready near gathering some more for your next meal. You are getting some kind of energy but at a great expense for you.
So when you society has a lot of steak, it can have a lot of free time, doing some cultural, technical or scientific discoveries. But when the steak is less available, they have to start harvesting for the mushrooms but they will restrain their cultural, technical or scientific activities.
The ethanol vs gasoline is the same than the steak vs mushrooms. You will eat steak, but mushrooms will take a greater and greater place and you will loose some time to do stuff.
Ethanol may be a "fluid container" of energy but it is not as tasty as the gasoline.
Have a good day.
Completly agree!
I think EROEI have been to much discused, and doing simple maths it can be checked.
I enjoyed a lot with your meat account. Thanks! I have no dinner today, despite I live in a very good quality mushroom's and steak's zone! ;)
But, despite of the "energy balance", ethanol could be a "provisional" solution to reduce GHG emissions, if not a fuel transport, as a good enviromental additive to gasoline.
Probably ethanol won't be the best solution, probably won't be definitive, I don't know, but I'm convinced we must develop or explore all possibilities.
- Diminishing returns on exploration
- No access to exploration process. (Saudi Arabia can use oil energy to explore for oil, but Thailand can't)
- Higher EROEI for non-corn ethanol
Brazilian sugar cane has a reported EROEI for 1:8.5 or more. This is believable since there are few external inputs to the process. It is documented in the studies that I have linked to elsewhere in this thread, one by the German government. Based on this the climate impacts are hugely positive - 87-95% reduction in lifecycle carbon emissions from cars. There are also benefits in terms of employment, economy, security, and risk management.Brazil has run a huge ethanol industry for many years. It is currently unsubsidized and producers are willing divert over half of all sugar produced to ethanol.
I think this is going to be a small solution and one that is most useful to oil exposed, developing tropical countries. But I do think it can be a bounty for them. And I live in one. I also think they are sane in the brain, even if you doubt that I am.
THIS IS PATENTLY NOT TRUE
Subsidies have several effects which add to ethanol's value.
First, national security. We are importing 60% of our oil, and many of the regions are politicially unstable if not outright hostile to the US. Ending these imports will cripple our economy and military.
Second, global warming. Ethanol is nearly carbon nuetral, while oil and coal are dirty as hell.
Third, votes in the Iowa Caucus. Our congressional leaders are all running for president, and the earliest poll is in a corn producing region.
Fourth, It is more important to start towards a sustainable energy policy than to do nothing. Ethanol will probably not be the ultimate solution, but it will darn sure be a step in the right direction.
Fith, Economic benefits from not exporting dollars to people who won't buy products in the US. Our balance of payments is wrecking our economy.
So let's add these benefits in to the equation, and save our energy for battleing for a winable fight.
Even if we can make ethanol work from an "energy efficiency" point of view is it part of the long term solution?
I just don't know the answer right now.
Sure, but a NON SOLUTION is not.
Given that there is NO WAY to make ethanol work from an "energy efficiency" point of view, now or ever, the question is moot.
So I think the question of whether we want to go to the trouble and time of developing/perfecting the technology oe ethanol production, rather than more electric, or "clean coal", or something else has to be the first question.
We have a limited amount of time and resources. I think a little time really thinking about how to approach the more general energy problem will serve us well. My inclination is that we would be better of thinking about electrification.
However, Brazil has already developed a production system that is considered mature. Thailand and other tropical countries could develop decent production scale in 2-3 years. They are miles behind on power production and if the US and EU go electric, the developing countries will get cheap second hand vehicles. Besides we are all waiting on battery technology and I see no reason to think it will have the penetration in developing countries in the next few years to make liquid fuels useless.
I understand this is not the holy grail, but do see it as a positive in an area where there are not a lot of success stories.
- CTL
- Electrification with ramp up of Nuclear, Wind Solar.
and I really would prefer option 2 from almost any consideration other than cost. I think this is where we need to focus our thinking.I see up to 10% of current levels of liquid fuel being provided by biofuels. Currently production of ethanol is a bout seven times that of biodiesel. In Brazil the EROEI od sugar cane derived ethanol is 1:8 or more. The climate benefits are huge. This could be replicated in Thailand, much of tropical Asia and Africa. I would much, much rather see this than CTL.
I do agree that in the long-term electricity will be the answer. I don't see die off happening either, but I do think that energy constraints could hurt the world economy badly.ot only would this impact the poor severely, i imagibne it could have ramnifications towards most people trading most things in Hong Kong.
I don't see why developing countries in tropical regions producing their own energy detracts from the pursuit of electrification elsewhere. However, i do agree that in the US it is a waste and resources would be better spent on improving batteries and making the grid support an electric vehicle infrastructure.
As I noted earlier, I think the US policy is a farm support program, not an energy program. As someone else noted, the loosening CAFE restrictions offsets any potential gain from ethanol.
But none of that has any bearing on suagr in the tropics. I am fighting to delink the two issues and analyse them on their spearate merits or lack thereof.
You don't have to, it's not a choice.
That sounds like a per-captia reduction over time, and at least a mild powerdown.
Actually, I think the answer is both. He will feel beaten up, but he will move his entertainment dollar to an activity where the reward is greater for a given input.
Your example is excellent. This is in fact exactly what I think will happen. Individuals will suffer, be pissed off, maybe lose their jobs, maybe die. But at a system level, we will learn to do the same, and maybe more, with less.
So, if these are the only 2 solutions that you see, I can't see how you can not "believe" in powerdown.
Uranium has not been prospected for in remotely the same intensity and geographic diversity than petroleum. And uranium was deposited in the formation of the solar system and is prevalent throughout the crust, unlike petroleum which needs a very specific biological and geophyiscal history to form. Consider that the big uranium states are also the ones with physically largest land mass.
Rock mining economics is quite different from petroleum.
To declare new reserves, miners have to drill new holes, usually right near the old ones, and assay in order to officially allocate new reserves.
They don't do this if they have more than a few years worth of production to go, but the chance that they will find new bookable reserves right nearby is very high compared to petroleum.
Petroleum you can prospect enormous areas with indirect seismic measurements, and suck it up, over enormous areas.
The physical size of the rocks mined for uranium is quite miniscule compared to the size of the oil fields and areas prospected for oil.
And then there are modifications to fuel cycles, completely within known laws of physics, which can greatly amplify the Energy Returned On Uranium Invested. And then there's thorium.
And maybe by then we'll be able to burn deuterium which has essentially no resource limitations.
It is destructively foolish to giving up on civilization without trying nuclear, under the assumption its future is another clone of petroleum.
Powerdown doesn't mean happy socialist kibbutzim making organic asparagus. It means warlords and death by bullet or machete or pestilence.
Tony
I followed your link from "now or never" and found virtually every one of your assumptions to be inaccurate. The inputs to ethanol are not pure crude oil and you don't add fertilizer, etc to get to the 1:1.25 ratio - it is already included. Neither do you need to convert from volume to BTU as the ratio is done on a BTU basis. Finally, while you say ethanol, the 1:1:25 ratio is from the more pessimistic one covering corn ethanol. Sugar cane does seem to achieve 1:8 and maybe even 1:10.
I'm sure if I had spent more than 10 seconds looking at your post, I would have found more mistakes, but honestly it is hard to spend that much time looking at your posts.
He's totally wrong.
Tony
First, ethanol is energy efficient.
Second, ethanol is already part of the long term solution.
There's your answer.
a)10% of 140 billion gallons p/a in 10 years?
b)20% of 140 billion gallons p/a in 20 years?
c)30% of 140 billion gallons p/a in 30 years?
Please note: there are other ways to make ethanol not just from the fermentation of food-chain feedstocks.
Here are five studies that all cite figures of positive 8-10 EROEI for ethanol from sugar cane. I have given page references for three of them and will find and post the others later.
1) FO Licht presentation to METI,
http://www.meti.go.jp/report/downloadfiles/g30819b40j.pdf
EROEI Calcs: Page 20
2) IEA Automotive Fuels for the Future
http://www.iea.org/textbase/nppdf/free/1990/autofuel99.pdf
3) IEA: Biofuels for Transport
http://www.iea.org/textbase/nppdf/free/2004/biofuels2004.pdf
EROEI calcs: page 60
4) Worldwatch Institute & Government of Germany: Biofuels for Transport (Link to register - study is free)
http://www.worldwatch.org/node/4078
EROEI Calcs (for 12 fuel types): Page 17
5) Potential for Biofuels for Transport in Developing Countries
http://www-wds.worldbank.org/external/default/WDSContentServer/IW3P/IB/2006/01/05/000090341_20060105 161036/Rendered/PDF/ESM3120PAPER0Biofuels.pdf
Furthermore
- Brazil is a net producer of petroleum and uses over-production to subsidize it ethanol business.
- is tragically tapping (and is destroying) a great and diverse fresh-water surface aquifer (the pantanal marsh) to grow the sugar cane.
- has great income disparity and uses this 'spare' agricultural land as a public-works program.
- Sugar cane production can destroy soil structure and is often abandoned after 3-4 years.
It is thermodynamic lunacy to believe that the fermented waste product of a highly entropic industrial agriculture system could power that system and still leak enough energy to drive mom and the kids to the soccer game.Your points 1, 2 and 3 are just surmise and seem inaccurate. How does Brazil use petroleum production to subsize ethanol? Ethanol is not irrigated, so how is it destroying an aquifer? I asked earlier for a citation on the abandoned field assertion, which I have never heard elsewhere. Point 3 seems like an addittional benefit.
It seem like lunacy to deny reality, which Brazilian ethanol is.
Good! an excellent "opportunity" for ENDLESS bickering .
It seem like lunacy to deny reality, which Brazilian ethanol is.
Brazilian ethanol "works" for the very reason you are rejecting : "additional energy that the humans use to harvest sugar cane" is NOT accounted for because it is not fungible in the current market context.
That is, if this energy were not employed here it would not be tradable in the current Global Market, so much for Globalization, another perverse effect.
if the USA was as energy independent as Brazil the US consumers would be cutting effective end user consumption by nearly a order of magnitude..
thats conceding your position on the reality of Brazilian ethanol..
ethanol replacement/substitution=economic contraction because the consumption levels are already high...
Boris
london
Ethanol production is less than 20% of their liquid fuel needs.
It does not care about the source of energy, but yes, you do have to take into account the labor for sugar cane.
Also EROEI can be explained this way :
ENERGY INVESTED is this -
In order to ACQUIRE energy, it TAKES ENERGY.
In order to TRANSPORT a form of energy, TAKES ENERGY.
In order to STORE energy, TAKES ENERGY.
In order to USE energy, also TAKES ENERGY.
ENERGY RETURNED is this -
After you have taken into account all the energy used above...how MUCH ENERGY do you have left? OR How much energy does it actually COST in order to USE a particular form of energy?
I hope you and others can get to read more about it. Great stuff has been written about it elsewhere. It is important to get more aquainted with this concept in order to be able to debate on this issue in a sound way.
8 workers at 3000/day calories is the cost in nutrition. Multiply this by 25-50(a reasonable multiplier that describe the true energy cost of modern support infrastructure.) and the energy equation is flipped
They're not jiving with my references.
I think I'm with Khosla on this one. Our nation is on the verge of bankruptcy because of our terrible oil import bill and our security is at risk because our oil payments subsidise a bunch of religeous nuts in Saudi and Kuwait and we need to make a start towards alternative energy. I hope his investments in battery research quickly bear fruit as I see renewable sources of electricity as being the ultimate good answer.
In 2005, US acreage planted=922,600 acres for a total harvest of 24.726 million tons at a national average of 28.8 tons per.
And for those of you in Nebraska, you can and do grow sugar beet quite well.
In 2005, US acreage planted=1.3 million acres for a total harvest of 27.537 million tons at a national average of 22.2 tons per.
Ethanol yields for each are as follows:
1 ton of sugarcane = approx. 20 gallons
1 ton of sugarbeet = approx. 24 gallons
All data derived from USDA.
I think it was about time the first world starts to pay back some of the wealth we stole from developing countries. Too bad it still ends up in the wrong hands...
There is plenty to be learned from the Brazilian experience and it's great to see someone actually differentiate between corn-ethanol, sugarcane ethanol, cellulosic and all the rest.
#5 above has HUGE implications for developing countries especially in the subtropic areas where sugarcane and similar biomass->biofuel feedstocks can be grown in abundance.
Gotta love the logic of the benighted...
I'll post a direct quote from the book as soon as I can, perhaps it can give something to this debate.
NO!
YOU are confuse!
See my arguments below.
To the people you were emailing, the subtle difference between how much energy is used verses how much fossil resource is used doesn't really matter.
- It's not clear that all fossil inputs and environmental issues are taken into account. (soil depletion, fertilizer production and contamination, difficulty of delivery, etc) Perhaps the problems of ethanol will outweigh the benefits.
- What happens to the 1.23/0.74 figure when ethanol production is scaled up so much that less-than-optimal farmland needs to be used? Marginal land will require more fertilizer, more water pumping, etc, and will lead to a much lower return. Perhaps even a negative return.
- With the backing of farmers, speculative investors trying to make a buck, and our "silver bullet" politicians, ethanol is being pushed way beyond practical levels. A better use of the public funds, public mindshare, and political capital would be to research a wide variety of technologies and push an agenda of personal and business conservation.
Here's something sad to think about... even with some miracle cellulosic production breakthrough, estimates are for only 10% displacement of gasoline. However, car companies can get 2 MPG "bonus points" from the CAFE standards by making cars that can run E85. So, the average light-vehicle fleet can be 20 MPG instead of 22 MPG because of the ethanol loophole (a 10% reduction in MPG). So... the pie-in-the-sky cellulosic ethanol benefit that might or might not happen only just barely overcomes the fuel-economey wast right now allowed by the CAFE loophole; if the country outlawed all use of ethanol (like in 1920), we would burn less gasoline as a result!Just thought I would let you know that the miracle workers in our lab are aiming for much higher than a measly 10% displacement of gasoline.
Oh and FYI... it's really not pie-in-the-sky cellulosic ethanol at all. It's called thermo-chemical conversion - a process that's been around now for quite some time.
Please feel free to learn more at www.syntecbiofuel.com
Why do you use the term bioreactor.
And next I though methanol has higher yields for syngas.
And finally if your process is competitive you should be able to sell your methanol today for a profit. Same for ethanol.
Better yet make something else out of the syngas.
Being yourself either an idiot or a "PR Troll" does not give credence to your statement, it comforts RR position.
I will try to restate the argument in the simplest form I can, not for your benefit but to counter your IDIOCY for the benefit of other readers and especially newcomers.
Say you have at hand 5 gallons of crude.
What do you choose to do with them?
- Refine them, burn 1 gallon for this and get 4 gallons of gasoline : 4 x 111,500 Btu = 446,000 Btu.
- Make ethanol, burn all 5 gallons PLUS all the raw materials and ressources land, water, fertilisers AT SOME EXTRA ENERGY COST to get 6.25 gallons of ethanol:
6.25 x 84,000 Btu = 525,000 Btu.
Ethanol wins...Yeah! ASSUMING ZERO COST/ENERGY for land, water, fertilisers or at least less than 79000 Btu for ALL raw ressources needed for 6.25 gallons of ethanol, BESIDE the energy needed for conversion.
How realistic is that?
Depending whether you are cost minded or EROEI minded you "just have" to PROVE that:
- The TOTAL energy needed to sustainably supply raw ressources for making 6.25 gallons of ethanol is less than 79000 Btu.
- Or, the COST of sustainably supplied raw ressources for making 6.25 gallons of ethanol is less than the cost of 79000 Btu of whatever sourcing at the CURRENT MARKET VALUE at the time of production.
It is this last cost argument which entertains the fallacy that ethanol is worthwhile because the way it runs is :If the cost of energy goes thru the roof, the raw materials costs will be cheaper than the cost of 79000 Btu.
NOT SO!
Because THIS cost of raw materials IS dependent on the cost of energy: energy is spent growing, collecting, maintaining the production infrastructure for these raw materials.
Since this complex supply chain cannot be exactly modelled with respect to its energy consumption, even less so for future structures of the supply chain, this is an "opportunity" for ENDLESS bickering about its financial bottom line.
It should be clear however that, NO MATTER the economic context, if the TOTAL energy consumed is above 79000 Btu to sustainably provide the raw materials needed to produce 6.25 gallons of ethanol, the economic outcome is a LOSS pure and simple!!!
This is the MARKET itself at play.
This is why EROEI matters and is the simplest and best way to gauge economic viability of ethanol production.
Sorry for this lengthy explanation, I hope it is clear enough.
Since the Ethanol Lobby seems to be sending the "cavalry" here at TOD we should all defend "the cause of rationality".
The bottom line is that once I have a barrel of oil, I can make ethanol or gasoline. From RR's numbers, it looks like you get more energy out of the barrel of oil by producing ethanol than you get by producing gasoline. From some of the things I read in this thread, it looks like with the right feed stock you can get much more energy from making ethanol.
I hear that sometimes. First, they claim that the efficiency of producing ethanol is greater. Then, when I rebut it, they claim it doesn't matter.
But it does matter. These water-muddying definitions that Argonne has utilized do a great public disservice. People hear that it is more efficient to produce ethanol than gasoline, so it seems like insanity that we aren't abandoning gasoline for ethanol. From a Peak Oil perspective, it is very dangerous because people presume we can just switch to ethanol, since it can be made with a higher efficiency than gasoline anyway. People need to understand that our energy situation is a lot more serious than these Argonne-style arguments would have you believe. We will not be able to transition our society to one run on biofuels, unless the EROI substantially improves. But Argonne is already misleading people into thinking everything is peachy, if we just adopt ethanol.
The bottom line is that once I have a barrel of oil, I can make ethanol or gasoline.
A barrel of oil is only a metaphor for the BTU content. You aren't really talking about literal barrels of oil. You don't make ethanol out of oil, and you don't extract oil from the ground using oil. We use various forms of energy, that can be represented as BTUs. If I have X BTUs, then I can invest it to make 5 BTUs of gasoline, or 1.3 BTUs of ethanol.
If it were so efficient to produce ethanol versus gasoline, then obviously we must cancel all corn and ethanol subsidies ASAP.
It is not only the efficiency of conversion, but also the rate of conversion that is important.
Tony
In the first case I refine it to gasoline and end up with 40 BTUs of gasoline.
In the second case I use it to make fertilzers, pesticides, diesel for the tractor, etc, grow some sugar crop, ferment it, distill it and end up with 67.5 BTUs of ethanol.
What am I missing here?
Sugar cane-based ethanol has a EROEI of 1:8.5 or more. So you could wind up with 425 BTUs.
Otherwise, I don't see any flaws in your logic and am delighted that you made the case more clearly than I seem to have done.
I haven't made any math errors. Perhaps you could point them out if you think I have. I happen to have a degree in math, so I am sure I can follow along.
VTPeakNik is a very gentile fellow and tried to explain it to RR, but RR was too focused to hear what VTPeakNik was saying.
No. He said first of all that he agrees with me that the claims are wrong (efficiency for corn ethanol better than for gasoline). That right there covers the main point of the essay. But the confusion comes in when people think we are talking about literal barrels of oil, when we are really talking about just energy; energy that could be invested in various projects. If I invest my BTUs into ethanol, I end up with far less energy than if I invest my BTUs into gasoline. Simple as that. The other arguments about sustainability, environmental impact, etc. are separate and should be considered on their own merits.
now I wonder... Will RR offer a public apology?
For what? Will you offer a public apology for wasting everyone's time and for making false accusations about math errors and such?
"To net 1 BTU of gasoline, I am only going to have to physically consume 0.26 BTUs of fossil fuel to get the oil out of the ground, refine it, and get it to your tank. I had to pull 1.26 BTUs of fossil fuel out of the ground to net 1.0 BTUs of gasoline. To net 1.0 BTUs of ethanol, I had to pull 3.84 BTUs of fossil fuel out of the ground"
But this is riddiculus. You don't gain anything when making gasoline. It is a net loss.
1 BTU gasoline out - 1.26 BTUs of oil in gives a net energy loss of -0.26 BTUs.
versus
1 BTU ethanol out - .74 BTUs of oil in gives a net energy gain of +0.26 BTUs.
You've misunderstood this "word problem", Mr "I have Math Degree". You don't net 1 BTU of energy when making gasoline. YOU HAVE A NET LOSS. And yes, you do owe an apology to Vinod, Wang and Tom for wasting their time. And you also owe a public apology to your readers for this riddiculs confusion you have brought to an otherwise straight forward discussion.
At best this is a math error on your part. At worst, it is sophistry. Are you man enough to publicly apologize, or are you going to continue to befuddle your your crowd of syccophants with this slight of hand you call math and logic that you claim escapes the feebleminded?
The elephant in the room is this: if we start with nothing other than one BTU of energy, we can choose to create gasoline or ethanol - if we choose gasoline, the first step is to get the oil, then refine it. If we choose ethanol, we have to get the corn, the natural gas, the oil, the coal, etc. From start to finish gasoline is a MUCH better energy investment, because the BTUs embodied in oil-in-place are so huge. Robert is not advocating anything other than those who advocate ethanol tell it straight of what they are comparing.
Some people get it, and some don't. Worse are those who don't get it, but think they do. Worst of all are those who don't get it, think they do, and proceed to make a fool out of themselves by insulting those who do get it.
One more time, because I know deep down you can get it if you really try hard. Put on your thinking cap:
1 BTU gasoline out - 1.26 BTUs of oil in gives a net energy loss of -0.26 BTUs.
versus
1 BTU ethanol out - .74 BTUs of oil in gives a net energy gain of +0.26 BTUs.
You are comparing the cradle to grave process for ethanol, to just the refining step for gasoline. Apples and oranges. You don't make ethanol out of oil. You make it mostly from natural gas. So, the portion that may be confusing you is thinking about a literal BTU of oil, and wondering whether it is better to turn it into 1.3 BTUs of ethanol, or 0.8 BTUs of gasoline. But that problem is a strawman, because you don't have a literal BTU of oil waiting to be turned into ethanol. Even if you did, that BTU first has to be refined into gasoline, diesel, etc., so your actual investment into ethanol would be less than the 1 BTU you had (based on the argument you are making).
But your worst mistake is not realizing that you are really talking about BTUs, and not literal oil. BTUs that I invested into ethanol production are fungible. I have alternative uses for them. Your BTUs are more efficiently invested into gasoline. If I have a BTU in hand, and I invest it into gasoline, I am going to end up with 4-5 BTUs of gasoline. You are going to end up with 1.3 BTUs of ethanol. That, my good man, is the bottom line.
No math errors on my part, just poor assumptions on your part leading to incorrect conclusions. Some people enjoy comparing apples to oranges. I prefer comparing apples to apples, so we can reach objective conclusions.
Now, I am going to take the advice I received from a couple of people by e-mail, and presume that you either can't or won't follow along, and to stop wasting my time with you. My parting advice for you is to carefully read thelastsasquatch's post above, and stop making a fool of yourself.
I could include the same cycle that produces the oil as part of the ethanol process. Then rather than getting .8 BTUs of gasoline which I could use to pump another 4 BTUs of oil, I get 1.35 BTUs of ethanol that could be use to pump another 6.75 BTUs of oil. There is nothing to say that the energy to pump oil had to come from gasoline. So at the end of the day I could have 6.75 BTUs versus 4 BTUs by incorporating the ethanol process.
So look at the process again:
Start with zero and by some means produce a BTU of oil.
You say that by making gasoline and losing .2 BTUs you end up with .8 BTU's that you reinvest in the pumping process and end up with 5 BTUs of oil that give 4 BTUs of gasoline.
Then you say if I make ethanol with that oil instead I get gasoline I end up with 1.35 BTUs of ethanol and that is all.
But why can't I reinvest those BTUs from ethanol to pump and additional 6.75 BTUs of oil just like you did with the gasoline. Then if I produce ethanol with those 6.75 BTUs I get 9.1 BTUs.
So then at the end of this mythical day I have 9.1 BTUs from ethanol compared to your measly 4 BTUs from gasoline.
Another way of looking at it is That to get those 4 BTUs of gasoline you have consumed 6 BTUs of oil.
But by incorporating ethanol production I got 9.1 BTUs and only consumed 7.75 BTUs of oil.
This is apples to apples. Your argument is shananagans, because you insist that because I have made BTUs from ethanol I can't reinvest those BTUs that way you have when making gasoline.
You will continually operate at a loss wasting oil 4:6. Whereas I get the benefit of captured solar energy and the process has a net gain 9.1:7.75
In fact it is silly to think that you can only reinvest energy you got from gasoline and not from ethanol.
I don't think that. What I insist upon is that you don't compare half of one process to the full life-cycle of another.
But why can't I reinvest those BTUs from ethanol to pump and additional 6.75 BTUs of oil just like you did with the gasoline. Then if I produce ethanol with those 6.75 BTUs I get 9.1 BTUs.
The most important thing here is draw your boundaries around exactly the same point. The issue under contention is whether it is more energy efficient to produce ethanol or gasoline. The only way to make that determination is to compare the two processes side by side by using consistent assumptions. In your example above, you are not doing that. All you are showing is that you can extend your BTUs by investing into ethanol. That is not in dispute.
The argument you are making is silly, because you aren't using consistent boundaries. If you want to reinvest those BTUs into a full life-cycle for ethanol, then the apples to apples comparison is to see how much you would get back by investing into the full life-cycle for gasoline. This is what you still aren't getting. You are restricting oil investments to the refining of oil (an apple), but you are looking at the cradle to grave process for ethanol (an orange).
This is apples to apples.
Horse apples to crabapples, maybe.
Your argument is shananagans, because you insist that because I have made BTUs from ethanol I can't reinvest those BTUs that way you have when making gasoline.
I insist on no such thing. I insist that when you reinvest those BTUs, you do so consistently for both processes. To this point, you haven't done so.
You will continually operate at a loss wasting oil 4:6. Whereas I get the benefit of captured solar energy and the process has a net gain 9.1:7.75
Right. By comparing a refining step for oil to a full life-cycle for ethanol. Invalid comparison.
Maybe this will help you out, if you want to start with 1 BTU of oil. What do I have to actually invest in the process to turn this oil into gasoline? I only have to physically consume 0.2 BTUs to turn 1 BTU of oil into 1 BTU of gasoline, diesel, etc. The 0.2 is the input. It is what was physically consumed. Likewise, I can physically consumed that 0.2 BTUs in the ethanol life-cycle to make 0.2*1.3 = 0.26 BTUs of ethanol.
The concept you are missing here is that of net energy. How much energy do you have to physically consume, and how much do you have left over? This is really not difficult. You are making it difficult by drawing your process boundaries differently for the two processes.
Efficiency is producing more with less. Clearly the example above (9.1 vs 4) says that one process making ethanol is more effecient than another process making gasoline. So your argument is that the life cycle for making ethanol can't be compared to the refining step for turning oil into gasoline. Hhmmm.
How is that an invalid comparison? The life cycle of ethanol is a refining step. It is very complex and slow perhaps, compared to refining gasoline, but you still put in energy (of several diverse forms) in one side and get energy (in another form) out the other side. In an abstract sense, how is that different that a process that refines oil to make gasoline? It is still energy of one form in, giving energy of another form out.
This is why I think you're playing word games.
By the way, I have been trying not to rachet my insults up any quicker than yours. If I got ahead of you, then I am sorry.
EROEI
gasoline = 1:8
ethanol = 1:1,2
8 > 1,2
gasoline > ethanol
Are you missing something?
They don't. They just have to be consistent for both processes. We can compare the refining step of both processes. We can compare the point up to the refining step for both processes. Or, we can compare the entire life-cycle. Where we get an invalid comparison is where we compare a life-cycle to a step. That is what you are doing.
I don't understand why these process boundaries have to be drawn as you are drawing them.
How is that an invalid comparison? The life cycle of ethanol is a refining step.
No, it isn't. The life cycle starts with nothing in hand, and calculates how many BTUs you have to spend to end up with product. It is cradle to grave. The refining step for ethanol would be starting with a barrel of crude ethanol (which is mostly water) and calculating how much energy it takes to extract the ethanol. That's an apples to apples comparison for how much energy it takes to refine a barrel of oil. When your starting point is a barrel of crude and the end point is gasoline, you aren't talking about a full life cycle. But the number for gasoline, 0.8, comes from just that refining step. The number for ethanol, 1.3, comes from the full life-cycle. That's why the comparison is invalid, and those who claim that this shows that ethanol has a higher efficiency are wrong.
This is why I think you're playing word games.
No, I am not playing word games. I am debunking a myth.
By the way, I have been trying not to rachet my insults up any quicker than yours. If I got ahead of you, then I am sorry.
While I don't consider "sleight of hand" insulting, I do consider "RR's rant" and "RR's mumbo jumbo" to be insulting, which occurred before I had responded to you. This is neither a rant, nor mumbo jumbo. In fact, it is quite simple if you just get it in your head to draw the boundaries in the same place for both processes. Any chemical engineer will tell you that it is absolutely critical when comparing processes to do so. Where you draw your boundaries matters, and if you draw them in different places when looking at different processes, you come up with nonsensical answers.
As long as you have oil to pump, you'll make a better use of it if you invest your BTUs in gasoline.
It's true that ethanol "captures solar energy" but, as far as you have the oil, it's better to transform oil into gasoline that to transform oil into ethanol.
"as far as you have oil" is the key here.
You do obtain "direct solar energy" in the ethanol process but you'll obtain far more "stored solar energy" if you just pump the oil and convert it into gasoline. Fossil fuels are stored solar energy.
Best
Fernando
What about for a country that has sugar production and can produce ethanol at an EROEI of 1:8.5, but has no oil? Sometimes you don't get to be the one that draws the boundaries and you can't move them just because they are inconsistent.
Yes, but not for now, and RR's main point still holds. In the future? Maybe, but not now as Wang and others are saying.
What about for a country that has sugar production and can produce ethanol at an EROEI of 1:8.5, but has no oil? Sometimes you don't get to be the one that draws the boundaries and you can't move them just because they are inconsistent.
"As long as you have oil" no longer holds, so, yes, it's better to use ethanol (I think).
I think RR's is just disputing one claim: that ethanol is currently "more efficient" than gasoline.
Best
Fernando
Best
Fernando
No, I only "hate" idiots and even much more so THOSE PANDERING TO THE IDIOTS.
Robert couldn't fit.
Oil comes from the ground. A fairly low amount of energy is needed to extract it.
The 100 BTUs of oil has to come from somewhere, it does not appear from thin air.
You do need to grow the biomass to get to the ethanol.
You need to extract crude oil to get gasoline.
Extracting the crude oil is the needed step in order to get gasoline. You do have to start from crude oil extraction.
So if I state it more correctly it becomes :
100 BTUs of oil.
50 BTUs fo get crude oil (500 BTU extracted) ends up with 400 BTUs of gasoline.
50 BTUs to make fertilzers, pesticides, diesel for the tractor, etc, grow some sugar crop, ferment it, distill it and end up with 67.5 BTUs of ethanol.
Can you see the difference?
You do know there is a difference.
Your talking nonsense.
No, he is pointing out your error. You looked at only the refining step for your 50 BTUs of oil, but you looked at the entire life-cycle for ethanol. Garbage in, garbage out. You have to compare apples to apples. Either compare the refining cycle for each, in which case gasoline comes out on top, or compare the full life-cycle for each, in which case gasoline comes out on top (efficiency-wise).
The very simplest way to envision this is to start with zero, and now invest 1 BTU. Where do you end up with the most energy?
Refining and ethanol production are equivalent steps. They both come after extraction of oil. You want to charge refining only the extraction rate and charge ethanol at post extraction rate. It is trickery.
Well, that's the whole point. They either need the high EROEI of the crude oil extraction.
From the begining you just want to compare Efficiency with EROEI. They are not the same thing. This is not a matter of boundaries of the systems.
And if you dont have the crude oil for extraction, you cannot use the ethanol for extracting the crude oil (this is the main point of peak oil)
And again, I'm not combining two processes. In the two systems, energy is needed to harvest (extract) the available energy.
The same way you cannot calculate the EROEI of ethanol starting from the fermented mixture, you cannot calculate the EROEI of gasoline without starting from the extraction.
Still a EROEI is NOT the same thing as efficiency in the refining process.
You dont need to use ethanol and gasoline for understanding that concept.
It's like :
meters is not seconds
percentage is not volume
pound is not velocity
speed is not acceleration
and
EROEI is not efficiency
How clearer can we be?
BTW it's not a matter of ethanol or gasoline, it's a matter of you not understanding a difference between two measures.
The last time I argued about someting as unscientific was when my father and I were arguing about gravity (he tought it was different for different objects on earth) anyway, try to just grasp the concept of difference between the unit of measure.
BTU, coal, ethanol, gasoline, electricity, system boundaries, etc are irrelevant in your example. You really need to figure the difference between efficiency and EROEI.
If anyone can help me on this, I was a college science teacher but I lack direct communication (verbal, non-verbal and para-verbal) to communicate effectively what is needed to understand.
I was willing to give some people the benefit of the doubt in the beginning, and I admit that some of this can be confusing. But I think the explanations that have been offered have been clear, and they have not been rebutted.
So, I don't think your communication skills are at fault. I think the problem is the comprehension skills of those you are communicating with. That's not an ad hominem; that's just the way I am beginning to see it. There is such a think as willful ignorance.
Well actually EROEI is almost exactly the Meriam-Webster definition for efficiency.
I am unable to change RRs view of his definitions of process boundaries, but I definately disagree with them. Not only that, I think I understand what he is saying, I just think he is making symantic distinctions, which in my opinion is artificial.
Honestly, the argument mostly seems to be that BTUs from oil are somehow better than BTUs from ethanol, with idiot thrown in to punctuate.
And the choir echos fragments and half truths. The choir claims that they can take their 0.8 BTUs of refined gasoline and pump 5 more BTUs of oil. But some how after producing 1.35 BTUs of ethanol, that's all I can have. And when I suggest that I can easily reinvest my 1.35 to pump an additional 6.75 BTUs of oil. But now I am supposedly violating some process boundary. It seems like "slight of hand" to me. And it is insulting, because in my opinion, RR has defined a process and way of comparison that is not inately obvious, and that after much thought is in my opinion wrong.
I think the arguments are so convoluted that most people grasp onto the piece that they can without walking through the whole thought process. And it is a shifting argument. In one place RR says that with 1 BTU of input energy he can end up with 4 BTUs of gasoline whereas with ethanol I would only get 1.35 BTUs. Then when I point out that I can also reinest those ethanol BTUs just as he did gasoline BTUs to pump 6.75 BTUs of oil and by using those BTUs to make more ethanol, I would end up with 9.1 BTUs. So he doesn't address that, but then tells me I have a process boundary problem and am comparing apples to oranges. But I can define the process boundary so that I am comfortable that it is apples to apples. And guess what. At the end of the day, I really do get 9.1 BTUs when making ethanol as compared to his 4 BTUs from gasoline. And that, again, is the Merriam-Webster definition of a more efficient process.
I think the post is confusing and ultimately wrong. And I think it is a shame that so many people here are willing to right off ethanol on the basis of this post. I think the incorporation of ethanol production into a small portion of the energy cycle would provide a substantial savings of a precious resource, and RR's bickering over terminology has been a great disservice to the public; the exact charge RR has leveled at the ethanol groups.
I am unable to change RRs view of his definitions of process boundaries, but I definately disagree with them.
You disagree because you are unable/unwilling to comprehend that in order to compare 2 processes, you must draw the boundaries consistently for both processes. If you argue that a mouse is bigger than a cat, and you "prove" this by comparing the cat's eye to the whole mouse, that is no different than what you have done here. Such a comparison is completely invalid, yet these are the comparisons you insist on making to demonstrate your point. Furthermore, this has been explained to you enough times that a high school student could understand it, provided they actually wanted to understand it.
Not only that, I think I understand what he is saying...
If you understand what I am saying, then you really are wasting everyone's time.
Honestly, the argument mostly seems to be that BTUs from oil are somehow better than BTUs from ethanol, with idiot thrown in to punctuate.
If this is what you got out of this discussion, then you got nothing at all out of it.
The choir claims that they can take their 0.8 BTUs of refined gasoline and pump 5 more BTUs of oil.
Sometimes you need to consider that when the choir is singing one song, and you are singing another, perhaps it is you who are singing the wrong song.
But now I am supposedly violating some process boundary. It seems like "slight of hand" to me.
You can draw your boundary for Process A wherever you like, provided you draw your boundary for Process B in the same location. If you don't take anything else away from this discussion, then you should remember this one.
So he doesn't address that, but then tells me I have a process boundary problem and am comparing apples to oranges.
This is an example of your insincerity. You say I don't address it, but then in the next breath admit that I did. I addressed it by pointing out that you got the answer you did because you drew your process boundaries differently for the 2 processes.
But I can define the process boundary so that I am comfortable that it is apples to apples.
It doesn't really matter if you are comfortable with it. If I draw process boundaries in different locations for 2 different processes, I can come up with any answer that I want. But it's garbage. It's like making up your own rules for algebra.
At the end of the day, I really do get 9.1 BTUs when making ethanol as compared to his 4 BTUs from gasoline. And that, again, is the Merriam-Webster definition of a more efficient process.
I hate to break this news to you, but Michael Wang e-mailed me last night, and he acknowledged that it is more efficient to produce gasoline than ethanol. He just said we need to broaden the argument (which I don't disagree with; this essay was specific to the efficiency claims). More on that in a few days, after I finish up some other items I am working on.
And I think it is a shame that so many people here are willing to right off ethanol on the basis of this post.
I don't think anyone has written off ethanol on the basis of this post. They are writing off claims that producing ethanol is a more efficient usage of our BTUs. This is about honestly debating the issues, not killing ethanol with 1 silver bullet.
I think the incorporation of ethanol production into a small portion of the energy cycle would provide a substantial savings of a precious resource...
You can think that the moon is made of green cheese, but at some point you have to support your arguments. I have shown that "substantial savings" is a complete nonstarter. At best, it is a very small savings. At worst, once all of the externalities are considered (soil erosion, etc.) it is a loss. As I see it, it is a lost opportunity with which we could be formulating better solutions.
That's it. I spent far more time on you than your posts warranted, but to be honest I wasn't really doing it for you.
Jack, I think that's your problem in a nutshell. You see literal barrels, when we are really talking about BTUs. We don't literally make ethanol out of oil. We make it primarily out of natural gas that went into fertilizer and was used in the distillation.
I understand your point very well. Once we have a BTU of oil out of the ground, aren't be better off turning it into 1.3 BTUs of ethanol than 0.8 BTUs of gasoline? But there are two mistakes there. First, you invested into the full life-cycle for ethanol. You had to make the fertilizer (from natural gas), you had to plant and harvest the corn, and you had to turn it into ethanol to get your 1.3 BTUs. This is no different than investing those BTUs into the full life-cycle for oil. The biomass has already been grown. Nature has done the heavy lifting for you. So instead of using your BTUs to grow the biomass, now you just use them to extract and process the biomass. Apples to apples.
The second mistake is in presuming we are dealing with literal barrels of oil to be turned into ethanol. The proper way to set up the problem is BTUs in and out. In fact, that is the way Argonne set up the problem. But their fatal flaw is to presume literal barrels in the case of gasoline, and fungible BTUs in the base of ethanol. If I have fungible BTUs, then investing in ethanol doesn't make much sense from an efficiency POV.
Would we be better off burning corn for home heating and using compressed natural gas for some transportation (say 5% or 10%) ?
Of course, your question was from an energy standpoint -there are other criteria (perhaps using NG for transport would result in more fatalities, etc?)
Tony
The gasification/fermentation process, for example, utilizes agricultural residues and wastes that would otherwise be placed in landfills, generates all its own energy and exports electricity and steam.
It essentially uses zero new BTUs to produce a gallon of ethanol (Transportation BTU are surely lower than oil transportation). This renders the discussion about the energy efficiency of ethanol obsolete.
What do you think we need to grow stuff right now?
diesel + fertilizers
What do you think is needed to ferment and distillate the ethanol?
Coal/nat gas
What is your assumption that it need zero BTU to produce a gallon of ethanol?
Thermodynamic laws is clear and notting like that can happen.
"Transpostation BTU are surely lower than oil transportation"
What do you mean by that sentence? BTU is BTU.
Man, you need to quit smoking suff.
What do you think we need to grow stuff right now?
If you use municipal wastes or crops, there is no additional energy cost. We plant for eat. Straw is waste!(I know that's not exactly true)
What do you think is needed to ferment and distillate the ethanol?
The gasification/fermentation process, doesn't need additional energy source (only to start the process up). Syntec told you before
What is your assumption that it need zero BTU to produce a gallon of ethanol?
Not truly zero BTU, but no additional BTU. (That's my fail)
Transpostation BTU are surely lower than oil transportation
I was talking about energy tranportation, excuse my fail, again!
Yes, reinvesting the crude oil energy into further crude oil production gives a better return on investment, but clearly we mainly produce oil to use it for all sorts of purposes in our societies. So why not leverage the oil energy to support the capture of additional 20+ percent solar energy for liquid fuels?
Someone pointed out that you can't easily turn oil/gasoline into ethanol, because coal and gas are usually used to support the ethanol process. However, this is mostly a technicality. I see only marginal technical reasons not to use oil to provide process heat to the distillation process, for example. (Of course, from an economic standpoint, as long as coal/gas is cheaper, you wouldn't use oil.)
A practical point in the opposite direction, which BaSe and others were missing is that using the oil to create ethanol would mean to decide between producing gasoline now and in huge quantities in existing refineries or - almost literally - breeding ethanol in a probably more time-consuming, more complex, multi-threaded process requiring the use of yet-to-cultivate field and yet-to-build conversion plants.
Apart from that, you could of course theoretically use ethanol to fuel the cruse oil extraction and following processes. The answer to the question if this is worthwhile energetically and economically would require a very detailed analysis, IMHO. (One of the aspects: lesser energy density of ethanol if compared to oil/gasoline requires more transport volume to get the ethanol to the oil extraction and processing sites)
Cheers,
Davidyson
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Hoping just means you don't have a good enough plan
Not really. To make your ethanol, that oil would be refined into Gas and Diesel (with known efficiency losses), and then burned to run tractors, pumps, etc, added to the other energies and materials required to end up with ethanol. (Land/Water/Labor..)
If you took that same energy from your refined oil, and put its gas back into running the oilfield, you'd still get some 5:1, 10:1 EROEI from that energy in new oil, whereas you'd only get that oft-cited 1.2:1 from your ethanol. Do you invest your money where you'll make 20% interest, or 500%? (and 400% after refining back to gas again)
Not worth the trouble. Stick to the same units and the message is painfully clear.
Not if you account for ALL energy inputs.
See the studies that I have linked to earlier.
Other studies have "been linked" which contradict this.
OK. Here's your chance: Show me one
Please provide your sources linked or otherwise.
Thank you for this clear and concise description.
Basically, instead of converting Crude to Gasoline, we can use crude to convert Corn to Ethanol, and we end up with ~60% more ethanol in terms of a burnable fuel.
And we don't even need Crude - we can use coal in place of the crude.
Of course this largely ignores the ecological costs in terms of water and soil depletion, as well as C02 generation by the coal input.
Also, if you think the Volatility in gasoline is bad now due to political reasons - just wait untill it's based on a crop!
Does someone have an estimate on how much gasoline 1 BTU of coal will produce in the CTL process?
After reading further in this thread, I want to make it clear, that the above numbers do nothing to make Ethanol a sustainable (solar based) fuel source. It could however make a big difference in helping us deal with peak oil. Transportation fuels will be needed.
The more I've read on The Oil drum, the more convinced I am that the only long term solution is depowering. Where I disagree with a lot of people on this board though is that I believe technology will allow us to keep a similar lifestyle at much lower energy levels.
Have there been any discussions about this in the past on the Oil Drum?
Current lifestyles are unsustainable, at any energy intensity, and so will have to change.
Tony