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Unforgiven 10-01-2008 02:16 AM

Ethanol-corn vs sawgrass
 
Taken from: http//:wholesalebiofuel.com

"When considering the total energy consumed by farm equipment, cultivation, planting, fertilizers, pesticides, herbicides, and fungicides made from petroleum, irrigation systems, harvesting, transport of feedstock to processing plants, fermentation, distillation, drying, transport to fuel terminals and retail pumps, and lower ethanol fuel energy content, the net energy content value added and delivered to consumers is very small. And, the net benefit (all things considered) does little to reduce un-sustainable imported oil and fossil fuels required to produce the ethanol."

Now somewhere in my past, I did a little hard searching and was finding some information that disturbed me. Corn ethanol production is what the government is wanting America to subscribe in, yet facts from various articles I could find suggested that corn ethanol was 9 times more costly in terms of development and production than petroleum gasoline. Saw grass ethanol was only 3 times more costly, before factoring in that saw grass has the potential to be harvested more than once a year. Even with the subsidy that the government offers on corn production, it just does not make sense to me why corn ethanol production should lead when the information I had seen clearly, to me, suggests that saw grass ethanol production will be a much better value and process.

Any ideas folks?

PS- and a last tidbit... why does the government want to make such a big deal out of a fuel that you have to use more of in order to get where you are going? Using more of it simply means more waste of energy in the first place.

trebuchet03 10-01-2008 03:08 AM

Ethanol tech is always advancing - I'm fairly confident current and future research will bring efficiency up. I'm also fairly confident that corn ethanol is not going to be a midterm or long term solution, but perhaps a short term.

As far as the costs, here's a more reliable source
petroleum.berkeley.edu/papers/patzek/CRPS416-Patzek-Web.pdf

Which shows a 7:1 ratio (energy in:energy out) with a max ideal ratio of 2.4:1.
------
As for why? I don't know... It's a good idea in theory - like the gold standard and magical perpetual motion machines, but it'll be awhile before the thought of returns are on the table. The US has a proud history of engineering it's way out of its troubles, I see no reason why energy solutions will be any different.

No offense to farmers.... but farmers have been fairly stupid over the past decades... "Oh noes, the price of corn dropped. It's okay, we'll just plant more corn next season to make up for it." (also applies to soy beans etc. etc.)

And seriously, I'm waiting for the great corn famine of 2015 (or whatever date) reminiscent of the days when a society put all their potatoes in one basket o.0

And the last bit of my rant... Has anyone else noticed TV commercials for HFCS? Yikes! Has anyone compared a coke from Mexico to a coke from the US? Coke uses cane sugar in it's Mexican recipe and HFCS in it's US recipe... The mexi-coke doesn't leave that nasty HFCS sticky coating on the back of your throat (yes, the taste is the same - but the texture is very different) ;)

Unforgiven 10-01-2008 03:29 AM

Ugh, sadly I fear you may be right on the corn famine issue. It will not be a pretty picture when it happens.
As far as energy efficiency developing, well darn it, work faster! Heh, all things compared, I find it a wonder that we were not focusing more on diesel engines long before this. Consider that early diesel engines were actually designed with plant oils in mind. Yay peanut oil and other used vegetable oils. Now if I only had one of those kits for filtration and use...

ConnClark 10-01-2008 04:25 AM

The big problem with corn ethanol is the amount of energy it takes to distill it to fuel grade. Another more pressing problem is dealing with the Acrolein gas given off during distillation. (Note Acrolein gas was used as a chemical weapon in WW1)

Since biodiesel is based off of oils it doesn't need to be distilled which give it a decisive advantage on energy return.

NeilBlanchard 10-01-2008 11:27 AM

Hi,

I think the OP meant to say switchgrass. It also might be possible to use the cornstalks, or fast growing willow trees.

Energy crop - Wikipedia, the free encyclopedia
Jatropha - Wikipedia, the free encyclopedia

Unforgiven 10-01-2008 01:28 PM

Nope, actually meant saw grass. And yes, the roughage or stalks from corn, and a couple of other crops can be used.

Nuclear Energy Can Save US: Insanity-The Only Word That Fits

Cladium - Wikipedia, the free encyclopedia

Is ethanol ready for its big break? - Autoblog

Ethanol a boondoggle, says Milken | Cleantech Group

Now, having said that, I did a little digging into switchgrass, and it does seem to hold promise like the aforementioned sawgrass.

Switchgrass gets high marks in new study | Cleantech Group

jamesqf 10-01-2008 02:13 PM

Quote:

Originally Posted by Unforgiven (Post 64484)
Corn ethanol production is what the government is wanting America to subscribe in, yet facts from various articles I could find suggested that corn ethanol was 9 times more costly in terms of development and production than petroleum gasoline.

As mentioned, you can juggle the figures to come up with whatever answer you want. Assume the worst case: that farmers will use the most energy-intensive techniques for growing & processing the corn, and you get more energy going in than coming out. Make different assumptions, and you get different answers. For example, if you're distilling the alcohol with oil-fired heaters, that obviously uses lots of oil. If you use waste heat from your local power plant, you get an entirely different answer.

As for why corn ethanol, maybe because we already have lots of farmers growing corn (so much that there was a surplus), plus practical experience of converting that corn into ethanol. So you start with what you have and know to create a market at least risk. Once that market exists - you know people will buy large amounts of ethanol at $2/gal or whatever - it becomes much less of a risk to invest in developing a cheaper feedstock or more efficient production methods.

Quote:

PS- and a last tidbit... why does the government want to make such a big deal out of a fuel that you have to use more of in order to get where you are going? Using more of it simply means more waste of energy in the first place.
Not sure quite what you mean there. Are you complaining that you get fewer miles from a gallon of ethanol than from a gallon of gasoline? But those are miles that didn't put fossil CO2 into the atmosphere or money in the jihadists' coffers. And they're miles that you can keep on driving even after all the oil wells are pumped dry :-)

Duffman 10-01-2008 02:42 PM

Quote:

Originally Posted by Unforgiven (Post 64484)
PS- and a last tidbit... why does the government want to make such a big deal out of a fuel that you have to use more of in order to get where you are going? Using more of it simply means more waste of energy in the first place.

The increase in fuel consumed (ethanol) is irrelevant because these studies are conducted on a energy balance method. It is generally accepted that corn ethanol has a balance of roughly 1.3:1. I dont know the value off the top of my head but if ethanol has 20% less energy than gasoline then you would have 25% (1/.8=1.25) more volume of fuel to have the same energy. So we get 25% more liters of ethanol than we would get if corn could be turned to gasoline instead, under the exact same processing conditions returning 1.3:1.

Unforgiven 10-01-2008 02:45 PM

I agree that the corn market was preexisting, although numbers that I hear about suggest that the surplus was not as great as they wish to let on. Practical experience heh, well corn and other grain alcohols have been around for decades for sure. It just seems to me that with all the development and research already in place that the cellulose ethanol extraction should be getting more attention instead of crop ethanol. Mind please that this is my perspective, and wont fit with many folks ideas.
As far as the carbon footprint issue perhaps you might want to relook at what equipment is used to farm the corn/grass/sileage that goes into ethanol. To me, a corn crop that needs to have a round of pesticide, and a round of herbacide (both needing a pass with the tractor or in some cases a plane) is not as good as sawgrass, which does not need the passes of herbacide or pestacide. I do hope that something is developed which can replace the fossil fuel. Until then, I look forward to hybrids, and the development of diesel-hybrid technology.

Unforgiven 10-01-2008 02:50 PM

Ok Duffman does not 25% more of something normally also mean 25% more processing costs? Granted that is not exactly true, but for this purpose, I am simply refering to the fact that it takes more ethanol fuel to travel the same distance in a vehicle. If it takes more energy to make the fuel to begin with, how much more energy are we losing with the fact that we have to burn more of the ethanol in order to go the distance we are used to with gasoline?

Duffman 10-01-2008 03:16 PM

No it doesnt because because again it is an energy analysis.

If a farm uses 1000 gal of gasoline (or energy equivalent other processes) to produce ethanol, it doesnt produce 1300 gal of ethanol, it produces 1300x1.25=1625 gal of ethanol. What we are doing is taking a concentrated energy source and turning it into a lower concentrated energy source but more of it (as well as running it through the 1.3 energy multiplier).

If you are having a hard time wrapping your head around it then think of ethanol as gasoline with 25% water added so they now have the same volume and energy content. And since water is practically free there is no cost associated.

Duffman 10-01-2008 03:32 PM

I think that a lot of empahsis has been placed on corn was to get the infrastructure off the ground. I am not a Chem Eng. but I would assume that converting a plant that makes ethanol from corn to a plant that makes ethanol from other sources is not a huge change or upgrade. I think the U.S. govt was/is trying to make conditions that when we figure out better sources for ethanol, the plants will be in place and the cars will be on the road already so the transition is a 1 year time frame instead of 10 years.

This is really why H2 cars will not take off, there is no infrastructure in place for people to buy the cars and nobody wants to build the infrastructure because there are no cars to use the fuel.

dremd 10-01-2008 03:51 PM

So; Just because the first tax credits were for inferior technology, then it is all bad?

I don't entirely believe these studies (I'd suspect that they are funded in part by oil). I do believe that you can make ethanol from corn using only farm energy sources just like Henry Ford intended the Mode T to be run off of in the first place.

Now I need to go dig some sources . . . .

Duffman 10-01-2008 04:07 PM

Dremd, here is a good article for you:

http://www.ethanol.org/pdf/contentmg...gy_Balance.pdf

jim-frank 10-01-2008 04:59 PM

Interesting discussion. I read lots of news about new tech issues, and one thing that is very interesting is using algae grown in vertical 'beds' (for lack of a better term). This process produces vastly more vegetable matter per acre than any other agricultural method. In addition, algae is very high in vegetable oil, and after extracting the oil, the remains can be fermented into ethanol (or other alcohols, with gene modified bacteria).

Vertigro video


One other thing- ethanol isn't the best alcohol by any means. Butanol has higher energy density and lower solubility with water.

If the processes to get alternative fuels can be made profitable, they will continue to proliferate.

dremd 10-01-2008 05:33 PM

Quote:

Originally Posted by Duffman (Post 64609)
Dremd, here is a good article for you:

http://www.ethanol.org/pdf/contentmg...gy_Balance.pdf

Thank you sir!

Just to clarify; I do not think that Ethanol is gods gift to man, just one of many small changes that can add up to a big change.

Unforgiven 10-01-2008 09:49 PM

Quote:

Originally Posted by Duffman (Post 64594)
No it doesnt because because again it is an energy analysis.

If a farm uses 1000 gal of gasoline (or energy equivalent other processes) to produce ethanol, it doesnt produce 1300 gal of ethanol, it produces 1300x1.25=1625 gal of ethanol. What we are doing is taking a concentrated energy source and turning it into a lower concentrated energy source but more of it (as well as running it through the 1.3 energy multiplier).

If you are having a hard time wrapping your head around it then think of ethanol as gasoline with 25% water added so they now have the same volume and energy content. And since water is practically free there is no cost associated.


Actually, the relation you show here for gasoline to ethanol is impossible. We dont make ethanol from gasoline...
What I am trying to get across here is that in the making of ethanol, from step one, we use gasoline in the tractors that are used to plant the corn, then spray the corn with a round of herbacide (more fuel used) a round of pestacide (again, more fuel used) and sometimes another round of the same if the bugs are really bad. Then harvesting costs, transportation, then the fuel and electricity costs to process the feedstock corn into ethanol. One small side benefit I hear is that the corn byproduct can be dried and ground into feed for the cattle and still be useful. Processing the sawgrass is not as fuel intensive like I mentioned before.

Oh, and the bit about algae I had forgotten about, thanks for the reminder!

jamesqf 10-02-2008 12:04 AM

Quote:

Originally Posted by Duffman (Post 64594)
If a farm uses 1000 gal of gasoline (or energy equivalent other processes) to produce ethanol, it doesnt produce 1300 gal of ethanol, it produces 1300x1.25=1625 gal of ethanol. What we are doing is taking a concentrated energy source and turning it into a lower concentrated energy source but more of it (as well as running it through the 1.3 energy multiplier).

Suppose we think about that a minute. First, using current tech you put in 1000 gallons of gas, and get out the equivalent of 1300 gallons. That seems like a net gain to me. Now if you only got 999 gallons out, and had no prospect of improvement, you'd have a good argument that the whole idea is a boondoggle.

Now remember that there are two things you want out of this process: 1) To get energy out of it; and 2) To get than energy in a concentrated liquid form that can run current engines. So thinking a bit, why does the energy in all have to be from gasoline? As mentioned, some/all of the processing could be done with waste heat from power plants. Or if you have farms that use center-pivot irrigation, it'd be fairly easy to adapt that to run electric tractors, harvesters, etc, with the electricity coming either from your farm wind turbines, or your friendly local nuclear plant.

Then there are probably better sources of feedstock than corn, or even switch/sawgrass. Using mixed native prairie plants produces more net energy, and wouldn't require lots of cultivation or chemicals: Prairie grasses emerge as rich energy source : UMNews : University of Minnesota And if the bottom falls out of the biofuel market, you could always graze a few buffalo :-)

NeilBlanchard 10-02-2008 01:11 PM

Hiya,

Corn is very fertilizer intensive (it is the "SUV" of farm crops!). And rather than pay for (expensive) crop insurance, many farmers use 2X the fertilizer recommended -- so, something like 200 pounds per acre?

Fertilizer is made from natural gas.

Do the GMF corn seeds take energy to grow? Probably, and most/all corn is hybrid anyway, so the farmer has to buy the seed, and the seed represents a fair bit of energy.

The chemical insecticides also come from petroleum, IIANM.

The tractor burns diesel usually, and it has to be used to prepare the soil (plow and harrow), and then to plant the seeds, and then again to spray insecticides (a couple of times?), and then again to harvest the corn. That is (at least) six passes around the field by the tractor.

If irrigation is needed, this takes electricity or some sort of pumps.

The corn then needs to be stored, transported, and then processed into methanol -- which takes more energy. Only the kernels are used, and I guess that the stalks are used for silage, usually?

Switchgrass is a native plant, and it doesn't need very much energy investment. Jatophra lives for about 50 years, and grows in marginal land that can't be farmed, and is drought resistant.

jamesqf 10-02-2008 02:34 PM

Quote:

Originally Posted by NeilBlanchard (Post 64819)
Corn is very fertilizer intensive (it is the "SUV" of farm crops!). And rather than pay for (expensive) crop insurance, many farmers use 2X the fertilizer recommended -- so, something like 200 pounds per acre?

That's a business decision. If the price of artificial fertilizers &c go up due to rising oil prices, the farmers will look at ways to use less. Consider recent interest in no-till farming methods, for instance.

Quote:

Fertilizer is made from natural gas.
Not necessarily. Mine's made by the neighbors' horses :-)

Quote:

Do the GMF corn seeds take energy to grow?
No more than any other seed. That's really the whole point of plants, you know. They grow by capturing energy from sunlight.

Quote:

The tractor burns diesel usually, and it has to be used to prepare the soil (plow and harrow)...
Again, these are business decisions. Diesel fuel, pesticides, and artifical fertilizers have been relatively cheap, as a consequence of cheap oil, and that economic fact has shaped the way farmers do things. But those technques aren't laws of nature: change the underlying economics (expensive oil), and the methods will change.

Quote:

Switchgrass is a native plant, and it doesn't need very much energy investment.
Corn is/was a native plant, too, before the Olmec/Maya/Aztec biotechnologists started tinkering with its genome. So what might happen with your native switchgrass or jatophra, once people start doing a bit of selective breeding? Then you have the whole spectrum of problems that arise when you try to grow monocultures of anything...

Once you actually start thinking about some of this stuff, it's nowhere near as clear-cut as some would like to think, but OTOH there are a lot more possibilities.

IndyIan 10-02-2008 02:48 PM

My main worry about bio fuels is that the micro nutrient cycle is being ignored. Copper, Iron, Selenium, etc are elements that are necessary for healthy plants and animals.
Eventually someone will figure out a way to convert cellulose to some sort of fuel and then any plant is fair game. If you mow things down for long enough and cart it all away eventually nothing will grow and we'll have bigger problems than figuring out how to drive around.

Corn is terrible for this and chemical fertillizers can mask the problem for a while but eventually the soil will be depleted.

Maybe the production of alcohol is so pure that it contains only carbon, hydrogen, and oxygen? Then the rest of the elements are salvagable and can be used for fertilizer again? I don't hear much about this but every farmer knows a field or two where someone grew corn for too many years and basically made it useless even with the standard fertillizers
Ian.

Unforgiven 10-02-2008 04:00 PM

Very true point on how a field can be burned out on a crop. I remember my paternal grandfather giving me that little instruction long ago which explained to me why he rotated fields to lay "fallow" as the term is used. Almost tempted to look into his old farm and see if the merits of raising sawgrass would be worth the effort...

jim-frank 10-02-2008 05:03 PM

Quote:

Originally Posted by Unforgiven (Post 64850)
Very true point on how a field can be burned out on a crop.

Modern farmers are quite aware of the need to rotate crops to avoid depletion of various nutrients.

I wonder how a cycle of [corn/sugar beets/something else] would work. Sugar beets are a good source of directly fermentable sugars, and the waste can be fed to animals or composted back into fertilizer.

There are lots of paths to any given end. It's mainly a matter of getting the government regulators cut out of the loop, and letting the farmers and ethanol producers decide for themselves what is the most economical and profitable route to take.

rmay635703 10-02-2008 09:32 PM

Quote:

Originally Posted by jim-frank (Post 64861)
Modern farmers are quite aware of the need to rotate crops to avoid depletion of various nutrients.

There are lots of paths to any given end. It's mainly a matter of getting the government regulators cut out of the loop, and letting the farmers and ethanol producers decide for themselves what is the most economical and profitable route to take.

Sadly most farmers aren't that modern. My relatives have been growing soy and corn only for over 25 years (my great uncle for 60yrs), no rotation to anything else. Current "hybrids" are designed to grow on water and nitrogen like a hydroponic. Our government stated that soil was devoid of mineral content in the 40's and warned of huge health effects from heart disease to anurism. Sadly they quit caring shortly after.

What is really needed in many parts of our country is a broad spectrum mineral based "Fertilizer" of some sort, best source would be ocean water if you could take out the sodium salt, though some studies say our soil needs some salt and in many areas there isn't even enough sodium content in the soil for it to be healthy. It would take many years though to start undoing the damage we have already done in our attempts to sterilize the soil.

We should also stop the practise of growing corn, the type of corn we grow is nutritionally devoid and not fit for human consumption without processing. Going to a traditional crop rotation with a variety of food crops would help break our dependance on foreign vegetables and fruits since we no longer grow much in the way of vegetables in mass.

We should also move from Beef to goats, sheep, deer, chickens, turkeys, pigs, etc. As they are all more efficient at converting food into meat and in some cases milk. Not that beef is bad just that it should not be our only real meat choice.

In terms of ethanol we should take the old slow method of malting, natural enzymes/yeast and WAITING. You can usually get away with not heating the mix in the summer months if you are willing to wait. We should not use fossil fuels to heat or distil. Sun dried Algae would make a great "heat" source burnt straight due to its oil content or any other biomass. No one seems much interested though in making a REAL green ethanol solution however as it means slower production or a larger footprint. Also waste foods should be used for ethanol or methane production, not viable food stores.

This all seems like common sense but when a lobby is involved nothing ever makes sense.

jim-frank 10-03-2008 10:18 AM

Quote:

Originally Posted by rmay635703 (Post 64919)
Sadly most farmers aren't that modern.

/snip/

In terms of ethanol we should take the old slow method of malting, natural enzymes/yeast and WAITING. You can usually get away with not heating the mix in the summer months if you are willing to wait. We should not use fossil fuels to heat or distil. Sun dried Algae would make a great "heat" source burnt straight due to its oil content or any other biomass.

Maybe Colorado farmers are at the cutting edge, then. :D

It's the heat to distill that really takes up energy. Water and ethanol make a mixture that's hard to distill, and only so much energy can be reclaimed by heat exchange between incoming and outgoing product streams.

I think the sun-dried algae idea sounds pretty good. I wonder how long it would take at the typical relative humidity in the midwest? Maybe they could spin dry the algae first in a centrifuge.

I've read about experiments to replace distillation with other processes like reverse osmosis and zeolite filtration, but no one has claimed any commercial applications so far.

I was reading about a higher temperature, catalyst based, biomass to alcohol conversion that looks promising. I'll see if I can find the reference.

An advantage to using bacteria rather than yeast is that tailored bacteria can produce butanol instead of ethanol. Since butanol is only mildly soluble in water, it simply floats to the top. I wonder is a tailored yeast could go from sugars to butanol?

jamesqf 10-03-2008 01:48 PM

Quote:

Originally Posted by jim-frank (Post 64978)
Maybe Colorado farmers are at the cutting edge, then. :D

Crop rotation is hardly cutting edge, considering that it was used in the Middle Ages: Farming in the Middle Ages

Or instead of a monoculture of any plant, consider mixed prairie. The plants are mostly perennials, so you just mow it now & then.

Quote:

It's the heat to distill that really takes up energy.
So use the waste heat from your local power plant.

jim-frank 10-03-2008 04:16 PM

Quote:

Crop rotation is hardly cutting edge, considering that it was used in the Middle Ages:
I was trying to be gentle. :rolleyes:

The waste heat from power plants is only relevant if you have a large steam driven power station in your ethanol plant's back yard.

Around here, the nearest large (coal fired) power plant is about 300 miles away. Everything local is hydroelectric except for some standby and emergency plants.


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