Another nail in the ethanol coffin?

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Another nail in the ethanol coffin?

Postby DrCloud on May 31st, 2009, 1:10 pm 

Comment: Replacing fossil fuels used for transportation -- and this is primarily oil, of course -- with something less CO2 intensive and more sustainable is an increasingly compelling problem. Although the installed infrastructure based on liquid fuels will present considerable economic and technological inertia for some time to come, long-term alternatives are worth exploring as well. The analysis in this paper shows that when a full analysis is employed, using biomass for conversion to electricity (and, therefore, battery-powered transportation) rather than conversion to ethanol is more sustainable.

As one who appreciates high-performance automobiles, I'm not sure I like this result, but there it is. If the battery problem can be overcome, however, I'll gladly purchase something like the Tesla vehicles. Currently, though, the batteries are too much of a kludge for me. HPH
==============

Greater Transportation Energy and GHG Offsets from Bioelectricity Than Ethanol
J. E. Campbell, D. B. Lobell, C. B. Field

Abstract: The quantity of land available to grow biofuel crops without affecting food prices or greenhouse gas (GHG) emissions from land conversion is limited. Therefore, bioenergy should maximize land-use efficiency when addressing transportation and climate change goals. Biomass could power either internal combustion or electric vehicles, but the relative land-use efficiency of these two energy pathways is not well quantified. Here, we show that bioelectricity outperforms ethanol across a range of feedstocks, conversion technologies, and vehicle classes. Bioelectricity produces an average of 81% more transportation kilometers and 108% more emissions offsets per unit area of cropland than does cellulosic ethanol. These results suggest that alternative bioenergy pathways have large differences in how efficiently they use the available land to achieve transportation and climate goals.

Originally published in Science Express on 7 May 2009
Print version in Science 22 May 2009: Vol. 324. no. 5930, pp. 1055 - 1057 DOI: 10.1126/science.1168885


(Note that this full article requires a Science magazine subscription or qualifying library for access, and it's copyrighted by the AAAS.)
DrCloud
 


Re: Another nail in the ethanol coffin?

Postby wolfhnd on May 31st, 2009, 1:50 pm 

The role of ethanol as a source of energy for local use at the individual farm should not be overlooked. The ethanol debate often ignores the more subtle aspects and focuses exclusively on the energy conversion rates.

Dan Keefe, manager of international operations for the U.S. Grains Council, tells EPM he can’t recall ever reading an article on the topic of food versus fuel in which it is stated that for every 100 tons of corn used for ethanol production there are 33 tons of quality, high-protein animal feed sold back to livestock producers. “It’s been grossly understated in the general media,” Keefe says. According to him, the world will never be satisfied with American agricultural policy.


“The leftover grain is fed wet to the cattle at the nearby feedlot, whose manure in turn powers the plant and creates high-quality fertilizer as a byproduct. Traditional ethanol plants have to invest in expensive, energy-intensive equipment to dry this leftover grain to prevent spoilage, and then transport it to far-off farms to use as feed. The on-site cows are treated to fresh wet cake from the nearby plant, thus avoiding both the cost and fossil fuel pollution of drying and transporting the grain.”


http://jcwinnie.biz/wordpress/?p=2419
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wolfhnd
 


Re: Another nail in the ethanol coffin?

Postby wolfhnd on May 31st, 2009, 5:17 pm 

In the previous post the image from the EPA shows ethanol as superior to bio diesel as a replacement for fossil fuels in terms of reducing green house emissions. This may or may not be accurate. The complexity of the industrial process for ethanol and the way that they interact with the economy as a whole make these questions very difficult.

I'm not a big fan of the corn subsidies and I think they are key in understanding why industrial corn is a bad idea. Even subsidies have the experts confused however as you can see from the following quotes.

According the the Financial Times, billions of taxpayer dollars were used to subsidize the corn ethanol industry. Early investors, including people like Bill Gates, have lost billions more because the self-same subsidies that were supposed to spawn an industry have ended up killing it.


After adding all the pluses and minuses together (including the two factors mentioned above), the Iowa State researchers concluded that ethanol subsidies have had the effect of lowering overall farm subsidies by $2.65 billion in 2007. That’s a chunky bit of savings for the US taxpayer.


http://gas2.org/2008/10/24/are-corn-eth ... nderstand/

If the experts can't even agree on the economics how will the scientists ever define the environmental consequences in a comprehensive way.
wolfhnd
 


Re: Another nail in the ethanol coffin?

Postby wolfhnd on June 2nd, 2009, 9:08 pm 

I'm disappointed to see that this thread has not taken off. This is something I feel is worth debating. The conversion of corn to high protein livestock feed has been something I have felt has been generally ignored in the ethanol debate as well as the amount of investment that would be wasted if ethanol production stopped.
wolfhnd
 


Postby DrCloud on June 5th, 2009, 8:33 pm 

I'll stop talking about nails and coffins, but additional information about this topic still seems worth mentioning. Here's another new abstract of a refereed paper that I ran across, quite ironically via a local TV station news report. It highlights the limitations of using crop residue for ethanol production. HPH
_______________________

Published online 3 April 2009
Published in Agron J 101:529-537 (2009)
DOI: 10.2134/agronj2008.0118x
© 2009 American Society of Agronomy
677 S. Segoe Rd., Madison, WI 53711 USA

BIOFUELS
Quantifying Straw Removal through Baling and Measuring the Long-Term Impact on Soil Quality and Wheat Production
G. P. Lafonda,*, M. Stumborgb, R. Lemkec, W. E. Maya, C. B. Holzapfeld and C. A. Campbelle

a Agriculture and Agri-Food Canada, Box 760, Indian Head, SK, Canada, S0G 2K0
bAgriculture and Agri-Food Canada, P.O. Box 1030, Swift Current, SK, Canada, S9H3X2
cAgriculture and Agri-Food Canada, Rm 5C10, 51 Campus Drive, Saskatoon, SK, S7N5A8
d Indian Head Agricultural Research Foundation, Box 156, Indian Head, SK, Canada, S0G2K0
eAgriculture and Agri-Food Canada, K.W. Neatby Building, Room 4107, 960 Carling Ave., Ottawa ON, Canada, K1A 0C6

* Corresponding Author (guy.lafond@agr.gc.ca).

Crop residues are considered the feedstock of choice for the production of ethanol, but removing crop residues may negatively impact soil productivity. The objectives were to quantify the proportion of total aboveground crop residues removed through baling and to evaluate the effects of 50 yr of straw removal with baling on soil quality and wheat (Triticum aestivum L.) production. The first study evaluated three harvesting systems and their impact on straw removal with baling. The second study measured straw removal after 50 yr on soil quality and wheat production using a fallow-spring wheat-spring wheat rotation (F-W-W) with three different treatments imposed. One treatment was not fertilized with straw retained, and the other two were fertilized with N and P but one treatment retained the straw while the other had the straw baled every year during the cropping years. The proportion of total aboveground residues other than grain removed with baling ranged from 22 to 35% or 26 to 40% depending on the method of calculation based on the first study. Measurements of soil organic carbon (SOC) and nitrogen (SON) showed no differences after 50 yr of straw removal, and spring wheat grain yields and grain protein concentration were also not affected based on the second study. The potential therefore exists to use crop residues for ethanol production or other industrial purposes without adversely affecting the long-term productivity of medium- to heavy-textured soils providing that <40% of the total aboveground residues other than grain are removed and the frequency of removal is no more than 2 yr out of three.
DrCloud
 


Re: Another nail in the ethanol coffin?

Postby wolfhnd on June 6th, 2009, 2:15 am 

DrCloud that is definitely part of the information we needed.

The use of petroleum based fertilizers as part of ethanol production is something that we need to avoid. The bigger picture is of course that fertilizers have sterilized the ground and we are now dependent on them to some extent. The authors however failed to mention this as an important consideration and seem to be saying that it is possible to use plant residue 2 out of 3 years.

The potential therefore exists to use crop residues for ethanol production or other industrial purposes without adversely affecting the long-term productivity of medium- to heavy-textured soils providing that <40% of the total aboveground residues other than grain are removed and the frequency of removal is no more than 2 yr out of three.
wolfhnd
 


Re: Another nail in the ethanol coffin?

Postby DrCloud on June 6th, 2009, 7:19 am 

Well, I think that's their main point (although I haven't read the full article) -- that it's not possible to harvest everything every year and expect the soil to continue to be fertile without the use of artificial fertilizers. What they seem to have done is to have quantified that obvious conclusion.

My interpretation is that their results will allow improved full-cycle estimates of ethanol production efficiency-- including all the side issues that were hidden or ignored in early analyses, issue such as non-sustainable harvesting practices and so on. HPH
DrCloud
 


Re: Another nail in the ethanol coffin?

Postby wolfhnd on June 6th, 2009, 5:51 pm 

If the current ethanol plants can be converted to use plant residue instead of water and fertilizer intensive corn that is a step in the right direction. I will have to research the quality of plant residue byproduct as animal feed.
wolfhnd
 


Re: Another nail in the ethanol coffin?

Postby wolfhnd on June 6th, 2009, 8:58 pm 

At this time cellulose ethanol does not produce a marketable livestock feed. It may not be the final nail but it certainly looks like investing huge amounts of money in biofuels is unwise.
wolfhnd
 


Re: Another nail in the ethanol coffin?

Postby DrCloud on June 6th, 2009, 9:18 pm 

If the investment can be separated from the politics, we might make some headway. After all, back when people heated their homes by burning firewood, they were using biofuels. And they lit oil lamps that burned (gasp!) whale oil, another old biofuel example. The problem now is more one of scale -- there are too many people and too few trees (not to mention whales) to make that work any more (and, of course, there's the air pollution problem as well).

Here in Florida, the leftovers from the sugar cane harvest -- the stuff called bagasse -- is being looked into, as are orange rinds (left over from making orange juice -- there's a surprising amount). Other crops will have similar possibilities, as long as we don't get too greedy, which, I think, was one point of the Agronomy Journal paper. And then there's algae.

In the sense that renewable energy solutions could well be the sum of lots of small contributions, perhaps it will all add up some day. HPH
DrCloud
 



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