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By Robert Rapier on Dec 22, 2011 with 39 responses

R-Squared Energy TV: Episode 6 – EROEI Explained

In this week’s episode of R-Squared Energy TV I present the first of several mini-presentations on energy topics of interest. The presentations will be short, 5 to 8 minute presentations with 3 to 5 slides each. This week’s presentation is on Energy Return on Energy Invested (EROEI). I believe there are a lot of misunderstandings from both proponents and opponents of EROEI methodology, and I attempt to clear up some of the misconceptions. Some of the questions answered are:

  • What exactly is EROEI?
  • Where might it be useful, and where might it possibly provide misleading answers?
  • What are the societal implications of a declining EROEI?
  • When is a lower EROEI process better than a higher EROEI process?
  • What does EROEI suggest about the economics of a process?

Readers who have specific questions can send them to ask [at] consumerenergyreport [dot] com or leave the question after this post (at the original source). Consider subscribing to our YouTube channel where you’ll be able to view past and future videos.

Link to Original Article: R-Squared Energy TV: Episode 6 – EROEI Explained

By Robert Rapier

  1. By Wendell Mercantile on December 22, 2011 at 11:15 am

    Well done. You need to discuss process efficiency. You just touched on it at the end, and as you said, the corn ethanol people always distort that (deliberately I suspect, although it’s also possible they have no idea what they are talking about).

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  2. By perry1961 on December 22, 2011 at 12:05 pm

    Corn ethanol seems terribly inefficient until you compare it to the EROEI of corn to meat. Grain-fed beef returns something like 1000 calories for every 8000 invested. Chickens and eggs are almost three times as efficient at 1:3. It doesn’t seem sustainable, but that’s the miracle of government subsidies.

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  3. By Rufus on December 22, 2011 at 12:59 pm

    That has nothing to do with “government subsidies.” It has Everything to do with the fact that people would rather have a Steak than a can of corn.

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  4. By perry1961 on December 22, 2011 at 1:11 pm

    I disagree Rufus. Here’s a graph of farm subsidies for various crops in 2005, before the big ethanol push. Why do you think corn/feed required much more subsidizing than soybeans or wheat? Could it be because steak would be unaffordable otherwise?

    http://en.wikipedia.org/wiki/F…..ffice).svg

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  5. By paul-n on December 22, 2011 at 1:22 pm

    Perry, Rufus nailed it – go and ask ten people how many prefer a steak to can of corn, and you will probably get eleven of them saying steak!

    Corn didn;t need the subsidies to keep beef prices down, it had the subsidies becasue the corn lobby has been very politically active – more so than the cattlemen.

    Sure chickens are more efficient converters of corn, but so what?  Does there need to be a government edict banning cattle on that basis?  

    Do we take away the right of farmers to raise whatever crops/animals as they see fit?  Have government defined diets?  Didn’t the Soviets try that?

     

     

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  6. By Rufus on December 22, 2011 at 1:32 pm

    There are 2.6 lbs of corn in a pound of beef.

    So, if corn rises $1.00 bu (about what the subsidy was, I guess,) you’re talking approx $0.05 more for a pound of beef.

    I doubt that that extra nickel for a 16oz T-Bone had much effect.

    The whole idea of ag subsidies (which just about Every Country in the World has) is to keep the small farmers in business during the lean times, so they’ll be available to produce, and compete, during the fat times.

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  7. By rrapier on December 22, 2011 at 1:54 pm

    perry1961 said:

    Corn ethanol seems terribly inefficient until you compare it to the EROEI of corn to meat. Grain-fed beef returns something like 1000 calories for every 8000 invested. Chickens and eggs are almost three times as efficient at 1:3. It doesn’t seem sustainable, but that’s the miracle of government subsidies.


     

    This gets into two issues. First is that corn and meat are not fungible. Of course they are both edible, and can both sustain a person, but people definitely have different preferences. To make an EROEI comparison of these two you would need to be comparing something like beef-fed beef (like they did in the UK that led to mad cow disease) or corn-fed corn. In that case, you can make a real EROEI comparison.

    But the more important issue is that these are not fuel. I heard someone make this comparison about Twinkies a couple of years ago. They said something like “It takes 10 calories of energy to produce 1 calorie of Twinkie.” My response to that was that we aren’t putting Twinkies in our cars. So where EROEI really matters is when you are evaluating the use of one fuel to make another, fungible fuel.

    RR

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  8. By rrapier on December 22, 2011 at 2:17 pm

    Rufus said:

    I would say that corn, and meat are more fungible than nat gas, and liquid fuels (gasoline, diesel, ethanol, etc.)


     

    That is actually the example I was thinking of: Natural gas and liquid fuels. You do have to make modifications to the process though if you are going to feed people the corn, because it isn’t the same kind of corn. Plus, the nutritional aspects are different so it changes up the rest of the diet.

    RR

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  9. By Rufus on December 22, 2011 at 2:14 pm

    I would say that corn, and meat are more fungible than nat gas, and liquid fuels (gasoline, diesel, ethanol, etc.)

    A “meat-eater” can function on corn with No Modifications, whereas an ICE must be modified before it can run on CNG.

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  10. By Rufus on December 22, 2011 at 2:28 pm

    Yeah, trying to subsist on a “corn diet” would, definitely, mean raising skinny, unhealthy kids.

    We have those “ripping, and tearing” teeth for a reason.

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  11. By paul-n on December 22, 2011 at 2:37 pm

    To rip the packet off the Twinkies?

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  12. By perry1961 on December 22, 2011 at 2:38 pm

    “Yeah, trying to subsist on a “corn diet” would, definitely, mean raising skinny, unhealthy kids.”

    Make that fat, unhealthy kids Rufus. Everything has corn sweetener nowadays, instead of sugar. From cokes and sports drinks, down to jam and peanut butter. Because of sugar subsidies and tariffs, high fructose corn syrup became much cheaper than sugar. If the studies on mice are to be believed, HFCS made them fat, aggressive, gave them cancer and diabetes, and they lived half as long.

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  13. By perry1961 on December 22, 2011 at 2:49 pm

    “This gets into two issues. First is that corn and meat are not fungible.”

    It does speak to best use of resources though. Energy in, energy out. If corn fed beef has an EROEI of 1:8, and pasture fed beef has an EROEI of 1:5, then maybe it’s best to use the corn for ethanol and return those cattle to pastures. Better yet, burn the corn for electricity and use that electricity to power motors that are 3X as efficient as ICE’s. If 40% of the corn crop can replace 10% of gasoline usage through ethanol, how much gasoline could it replace through the widespread use of EV’s? My hunch is 50% or more.

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  14. By Rufus on December 22, 2011 at 2:55 pm

    Then again, what is the EROEI of an EV sitting on the side of the road with a dead battery, and a frustrated salesman/businessman?

    Or, what is the eroei of paying landowners NOT to Plant 30 Million Acres?

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  15. By paul-n on December 22, 2011 at 2:58 pm

    Fructose is the real culprit here – glucose is actually quite benign (and is brain food!)

     

    If you can take the time, this is a great presentation on the topic by Dr Robert Lustig (of Sugar – The Bitter Truth fame) – some great insights into how digestion of fructose causes so many problems.  

    http://www.youtube.com/watch?v…..re=related

     

    I’d much rather eat steak!

    In fact, using the corn to make ethanol is probably, overall, better for the nation’s health than eating it!

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  16. By Rufus on December 22, 2011 at 2:59 pm

    On the other hand, the eroei of unhooking a “trailer” from the back of a diesel-burning truck, and putting it on the back of an Electrified Train has to be enormous.

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  17. By Rufus on December 22, 2011 at 3:03 pm

    Especially, if most of the electricity for the train is supplied by Solar, Wind, and Geothermal.

    Maybe that’s what Warren Buffet is thinking, no?

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  18. By Rufus on December 22, 2011 at 4:22 pm

    Our economy seems to be in the “Sweet Spot” at around $0.10/mile.

    In 2011 gas prices averaged $3.50, and average mpg for the fleet was probably not much better than 20 mpg. $0.17 per mile. Tough sledding for the bottom two quintiles, for sure.

    It looks to me like a worthwhile goal in the medium term is somewhere around 30 mpg on $3.00/gal cellulosic ethanol. The 30 mpg won’t be so tough, but the $3.00 Cellulosic (retail) is still a jump ball.

    We’ll see (in a year, or two, anyway.) :)

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  19. By Wendell Mercantile on December 22, 2011 at 5:04 pm

    The 30 mpg won’t be so tough, but the $3.00 Cellulosic (retail) is still a jump ball.

    Negative Rufus, the logistics of making cellulosic ethanol will be the jump ball. (Or as I like to say, “The long pole in the tent.”)

    I know, I repeat myself, but you continually ignore the real-world example of the 40 MW power plant in my part of the country that two years ago converted to burning only biomass. 40 MW is small for an electrical-generation station, yet they have had to range out as far as 120-miles to find biomass to keep their turbines spinning. And is in a fertile part of the Midwest where one would think there would be more than enough biomass.

    That is a logistics problem, they didn’t anticipate, or probably even consider. They are finding that ranging out 120-miles to collect biomass may not be worth the cost of the electricity they are generating for their electrical co-op consumers.

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  20. By Rufus on December 22, 2011 at 5:18 pm

    I Did consider logistics, Wendell. Years ago, when I posited that the future of ethanol was SMALL Plants (10 – 15 Million Gal/Yr.)

    And, LOCALLY Situated.

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  21. By perry1961 on December 22, 2011 at 6:27 pm

    Rufus, we aren’t going to grow our way out of this hole with ethanol, cellulosic or not. A bushel of corn starts out with 352,000 btu’s. Converting it to ethanol reduces that to 160,000 btu’s, and uses over 50,000 btu’s of process steam along the way. Cellulosic from corn stover uses twice the process steam.

    Burning the corn at 70% efficiency would return 240,000 btu’s per bushel. Put that into a PHEV(if you never want to be stuck beside the highway) that uses a 90% efficient motor, and that bushel of corn will take you 5X as far. If the dual use of corn gives folks angst, grow switchgrass instead.

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  22. By Rufus on December 22, 2011 at 6:38 pm

    Perry, I will agree that PHEVs will contribute to our increasing our mpgs.

    The solution must be multi-faceted.

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  23. By perry1961 on December 22, 2011 at 6:56 pm

    By the time cellulosic ethanol makes a dent in the problem, gasoline will be $12 a gallon, assuming oil prices continue to double every 10 years. Sorry Rufus, but I doubt Americans will be that patient. I give it 10 years (tops) before EV’s go mainstream with the middle class. I have trouble picturing an ICE on a new car lot 20 years down the road.

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  24. By Rufus on December 22, 2011 at 7:20 pm

    I don’t think so, Perry. Plug-ins are expensive, and EVs don’t have the range that many people need. They will each find a market, but the ICE will, most likely, be with us for a long time.

    Right now, Cellulosic is being held up by the Uncertainties in, both, the politics, and in the availability, and price, of oil. An operating, and profitable, operating cellulosic plant, such as the one being constructed in Fl, right now, will provide a powerful jumpstart to the industry.

    This IS the United States of America. The same United States that threw 14 Billion gallons/yr of corn ethanol onto the market in just a couple of years. Things can move fast, here, once the time is right.

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  25. By Wendell Mercantile on December 22, 2011 at 8:51 pm

    Years ago, when I posited that the future of ethanol was SMALL Plants (10 – 15 Million Gal/Yr.)

    What? Then you lose the production advantages that scale gives.

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  26. By Rufus on December 22, 2011 at 9:09 pm

    They studied 50 mgy ethanol plants vs 100 mgy plants and found no efficiency gain per size.

    If there were a small difference it would be more than made up for by the reduced need for transporting feedstock, and then the finished product.

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  27. By Wendell Mercantile on December 22, 2011 at 11:22 pm

    They studied 50 mgy ethanol plants vs 100 mgy plants and found no efficiency gain per size.

    They? Who is they?

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  28. By rufus on December 22, 2011 at 11:27 pm

    Cain’t remember. I got CRS.

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  29. By rrapier on December 23, 2011 at 12:16 am

    Rufus said:

    They studied 50 mgy ethanol plants vs 100 mgy plants and found no efficiency gain per size.


     

    It isn’t a matter of efficiency. It is a matter of fixed and operating costs per gallon of product.

    RR

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  30. By OD on December 23, 2011 at 9:20 pm

    Well, it looks like some Philly, PA refineries are suffering from low EROEI as Sunoco halts production at 2 refineries and might add a 3rd, which will amount to 700,000mbd that the Northeast will have to import from somewhere else. I have to say as a new resident of the Northeast, this is a worrisome development.

    I really wish our landlord would change the boiler to natural gas. We already have natural gas for our stove and fireplace. We are paying around $490 for approx. 6-7 weeks of fuel oil, and that’s with having the furnace on 60 and supplementing with space heaters. I guess I should be glad this winter has been mild.

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  31. By Wendell Mercantile on December 25, 2011 at 11:54 am

    Cain’t remember. I got CRS.

    Rufus~

    You’ll have to do better than that when you walk into the Tunica Citizens Bank & Trust and ask for a line credit to develop your first 50 mpg local, Tunica County ethanol plant.

    Unless you and the bank president go way back as members of the Rotary or Sons of the Confederacy, I suspect he’ll turn down your request, or at the very list ask for some specifics beyond, “I did consider logistics. Years ago, when I posited that the future of ethanol was SMALL Plants (10 – 15 Million Gal/Yr.)

    Merry Christmas!

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  32. By rufus on December 25, 2011 at 12:21 pm

    I’m too old for that play, Wendell. And, even if I wasn’t, the timing isn’t, yet, right. Three things still have to happen.

    1) We need a couple of years of $4.00 Gasoline

    2) We need much better flexfuel cars, and

    3) The Big Boys need to refine the cellulosic process (from gathering, to distribution.)

    Also, even what we refer to as “small” biorefineries will probably be too large for the “hometown” banks. The smallest participants will, most likely, be the “Regionals,” and, then, only with “Large” partners, and Gov. guarantees.

    I have, btw, chatted about this with a couple of “home town” bankers, and the younger ones bounce up and down like kids anticipating Christmas when they talk about the possibilities.

    These things take time, and the present “Politics” are horrendous.

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  33. By Wendell Mercantile on December 26, 2011 at 12:01 am

    We need much better flexfuel cars, and…

    Roger that!

    We need passing of the Open Fuels Standards Act. Which however, would open the door for using methanal, dimethyl ether, ammonia, etc. In a true open fuels market, all would be serious kick to the head for the corn ethanol boys and hydrogen fuel cell dreamers.

    Development of an ammonia fuel cell would have all the advantages of a hydrogen fuel cell, with almost none of the daunting logistics and infrastructure problems of either a very high-pressure or cryogenic hydrogen infrastructure.

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  34. By Lance Tischhauser on December 26, 2011 at 6:19 pm

    Robert,
    How do you account for the co-product distillers grains in your energy calculations. I am quite a lazy activist so I don’t know the numbers of calories left in the DDGs after the fermentation process, but there is a value there. Shouldn’t it come close to replacing the corn that would otherwise be fed to cattle on an energy basis? Another way of asking, shouldn’t it count as a positive energy credit to ethanol production, at the same amount of energy needed to produce corn that is fed to livestock? Just curious how you look at it. Warning – my opinions are surely biased as I am a corn farmer and benefit from the ethanol industry.

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  35. By Lance Tischhauser on December 26, 2011 at 6:21 pm

    I found this, don’t know if it helps:

     

    “A third of the grain that goes into ethanol production comes out as DDGS. Each bushel of grain used in the ethanol-making process produces 2.7 gallons of ethanol; 18 pounds of DDGS and 18 pounds of carbon dioxide.”
     

    http://www.ksgrains.com/ethano…../ddgs.html

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  36. By rrapier on December 26, 2011 at 6:28 pm

    Lance Tischhauser said:

    Robert,

    How do you account for the co-product distillers grains in your energy calculations. I am quite a lazy activist so I don’t know the numbers of calories left in the DDGs after the fermentation process, but there is a value there. Shouldn’t it come close to replacing the corn that would otherwise be fed to cattle on an energy basis? Another way of asking, shouldn’t it count as a positive energy credit to ethanol production, at the same amount of energy needed to produce corn that is fed to livestock? Just curious how you look at it. Warning – my opinions are surely biased as I am a corn farmer and benefit from the ethanol industry.


     

    Hi Lance,

    I went into some detail on this in Fun with Numbers. The gist is that the USDA has tried several different ways of calculating it. I think the most accurate method is the replacement method; that is how much energy would it have taken to produce the alternative to the DDGS? The USDA has simply allocated a lot of the energy into the DDGS to inflate the EROEI of the corn ethanol piece, leading some to incorrectly state that for 1 BTU of input you get 2.4 BTUs of ethanol output. That is inaccurate (and again I go into great detail in the linked essay).

    RR

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  37. By Lance Tischhauser on December 26, 2011 at 7:11 pm

    Very interesting. All USDA number fudging aside, does this show an improvement in the energy efficiency for ethanol production over that eight year time? Also, why would you presume that the energy content of the DDGs would be the same in 2010 as it was in 2002? Isn’t it conceivable that the industry could/would improve the quality (energy) in a product coming from the same pound of corn? I don’t know that to be true as I am not a producer of ethanol, only a consumer. Since you have analyzed the data, and I have not, I will ask another question. Does the USDA account for changes (improvements) in the production of the corn in terms of lbs of inputs (fertilizer, diesel) used per lbs of corn produced?
    Thanks

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  38. By Wendell Mercantile on December 26, 2011 at 8:58 pm

    I am quite a lazy activist so I don’t know the numbers of calories left in the DDGs after the fermentation process, but there is a value there.

    Lance~

    One thing to understand about the calories (or Btus) in DDGS is that distilling ethanol from fermented corn mash doesn’t add them. Those Btus were already in the corn because of the synthetic nitrogen fertilizers, sunlight, and water used to grow that corn. Turning that corn into ethanol adds nada to the energy content in the DDGS. (I will stipulate the DDGS has energy in it, and it would be wasteful not to take advantage of it — but it doesn’t benefit the EROEI of making corn ethanol.)

    It’s just that the crafty corn ethanol lobby (aided by the research of Dr Michael Wang of the Argonne National Lab in Illinois corn country) decided to use it as a subtle accounting trick to “pump up” ethanol’s apparent EROEI to something more than unity — a trick most people other those such as RR overlook.

    Also, why would you presume that the energy content of the DDGs would be the same in 2010 as it was in 2002?

    Lucas~

    See above. That energy gets in the DDGS when the corn grows. Figure out a way to use less fertilizer, less Sun, less water, less diesel fuel, less embodied energy in transportation and ag equipment, and less electricity to grow the same amount of corn, and the EROEI will improve. But it’s not because of any improvement at corn ethanol distilleries.

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  39. By rrapier on December 26, 2011 at 9:40 pm

    Lance Tischhauser said:

    Very interesting. All USDA number fudging aside, does this show an improvement in the energy efficiency for ethanol production over that eight year time? Also, why would you presume that the energy content of the DDGs would be the same in 2010 as it was in 2002? 


     

    The efficiency of the process has improved, which one would expect as the industry matured. The DDGS — as Wendell points out — is a function of the corn that it is derived from and isn’t likely to be much different energy wise than it was.

    Does the USDA account for changes (improvements) in the production of
    the corn in terms of lbs of inputs (fertilizer, diesel) used per lbs of
    corn produced?

    Yes. They have done a series of reports on this, examining all of those energy inputs across major corn-producing states.

     

    RR

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