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Switchgrass Ethanol Yields Large Net Energy Gain (mentioned by Tony Snow)
Environment News Service ^ | 01/08/2008

Posted on 01/09/2008 10:43:39 AM PST by cogitator

LINCOLN, Nebraska, January 8, 2008 - (ENS) - Switchgrass grown for biofuel production produced five times more energy than needed to grow, harvest and process it into cellulosic ethanol, finds a large farm study by researchers at the University of Nebraska-Lincoln published Monday.

The five year study also found greenhouse gas emissions from cellulosic ethanol made from switchgrass were 94 percent lower than estimated greenhouse gas emissions from gasoline production.

"This clearly demonstrates that switchgrass is not only energy efficient, but can be used in a renewable biofuel economy to reduce reliance of fossil fuels, reduce greenhouse gas emissions and enhance rural economies," said principal researcher Ken Vogel, a U.S. Department of Agriculture-Agricultural Research Service geneticist in the university's agronomy and horticulture department.

In a biorefinery, switchgrass biomass can be broken down into sugars including glucose and xylose that can be fermented into ethanol similar to corn. Grain from corn and other annual cereal grains, such as sorghum, are now primary sources for ethanol production in the U.S.

In the future, perennial crops, such as switchgrass, as well as crop residues and forestry biomass could be developed as major cellulosic ethanol sources that could potentially displace 30 percent of current U.S. petroleum consumption, Vogel said.

Technology to convert biomass into cellulosic ethanol is now at the development stage. Six small commercial scale biorefineries are being built with scale-up support from the U.S. Department of Energy.

Vogel's study involved switchgrass fields on farms in Nebraska, North Dakota and South Dakota. It is the largest study to date examining the net energy output, greenhouse gas emissions, biomass yields, agricultural inputs and estimated cellulosic ethanol production from switchgrass grown and managed for biomass fuel.

The study took place on 10 fields of 15 to 20 acres each with four in Nebraska near Atkinson, Crofton, Lawrence and Douglas; four in South Dakota near Highmore, Bristol, Huron and Ethan; and two in North Dakota near Streeter and Munich.

Trials began in 2000 and 2001 and continued for five years. Farmers were paid for their work under contract with the university and documented all production operations, agricultural inputs and biomass yields. The researchers used this information to determine the net energy estimates.

Switchgrass grown in this study yielded 93 percent more biomass per acre and an estimated 93 percent more net energy yield than previously estimated in a study done elsewhere of planted prairies in Minnesota that received low agricultural inputs, Vogel said.

Less land will be needed for energy crops if higher yields can be obtained.

Researchers point out in the study that plant biomass remaining after ethanol production could be used to provide the energy needed for the distilling process and other power requirements of the biorefinery. This results in a high net energy value for ethanol produced from switchgrass.

By contrast, corn grain ethanol biorefineries must use natural gas or other sources of energy for the conversion process.

In this study, switchgrass managed as a bioenergy crop produced estimated ethanol yields per acre similar to those from corn grown in the same states and years based on statewide average grain yields.

But higher yields compared to corn can be expected in the future, said Vogel, who points out that corn grain conversion technology is mature, while cellulosic conversion efficiency technology is still developing.

Vogel said he does not expect switchgrass to replace corn or other crops on Class 1 farm land. He and his colleagues are developing the grass for use on marginal, highly erodible lands similar to that currently in the federal Conservation Reserve Program. All the fields in this study met the qualifying criteria for that program.

Researchers found that switchgrass grown on the marginal fields produced an average of 300 gallons of ethanol per acre compared to average ethanol yields of 350 gallons per acre for corn for the same three states.

The researchers point out that this was a baseline study. The switchgrass cultivars used in this study were developed for use in pastures. New higher yielding cultivars are under development for specific use in bioenergy production systems.

Switchgrass yields continue to improve, Vogel said. Recent yield trials of new experimental strains in the three states produced 50 percent higher yields than achieved in this study.

Switchgrass in this study employed UNL's best management practices for switchgrass, including no-till seeding, herbicides, weed control and adaptive cultivars.

Six cellulosic biorefineries that are being co-funded by the U.S. Department of Energy also are in the works across the United States. These plants are expected to produce more than 130 million gallons of cellulosic ethanol per year.

Researchers reported their findings in the current issue of "Proceedings of the National Academy of Sciences," online at: Abstract


TOPICS: Business/Economy; Culture/Society; Extended News; Government; US: Nebraska
KEYWORDS: agriculture; agw; energy; ethanol; fuel; switchgrass
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To: cogitator

How we bend over backwards to keep the movie stars from seeing oil rigs off the coast through their telescopes, and not disturb the landscape that perhaps 1 in 250,000 Americans will ever see in ANWR... Oh, and keep the no-nukes crowd happy.

Can we have an energy policy rather than an energy dogma someday?


21 posted on 01/09/2008 11:24:17 AM PST by kingu (Fred08 - The Constitution is the value I'm voting for. What value are you voting for?)
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To: cogitator

If they use switchgrass for fuel it will artificially inflate the cost of good switches and kids won’t get their proper discipline. Tax on conservatives again!


22 posted on 01/09/2008 11:24:43 AM PST by Rippin
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To: z3n

As far as I know, all photosynthesis is six molecules of water plus six molecules of carbon dioxide produces one molecule of sugar plus six molecules of oxygen.

I believe the relative advantages are in other inputs to crop growth.

Since enzyme progress has been the actual key to cheaper corn ethanol, there’s no reason to think it won’t be the key to other biomass ethanol.


23 posted on 01/09/2008 11:28:07 AM PST by jjotto ("Ya could look it up!")
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To: Cracker Jack

I worked out the math here cause it didn’t add up to me. The US used up about 150 gallons of gasoline per year. Figuring in the 300 gallons per acre cited and 80 million acres of land used to grow corn...turns out that if every single acre we used to grow corn was converted to switch grass, we’d have to grow 7 crops a year to switch to an all ethanol economy.

That said, we have a lot of little used land out west that would be perfect for growing this stuff.


24 posted on 01/09/2008 11:29:55 AM PST by Raymann
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To: cogitator

Which is why any article mentioning ‘greenhouse gas’ in relation to ethanol is probably just bs anyway.


25 posted on 01/09/2008 11:31:38 AM PST by jjotto ("Ya could look it up!")
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To: kingu
How we bend over backwards to keep the movie stars from seeing oil rigs off the coast through their telescopes,

I don't mind bending over backwards if it means reducing the occurrence of things like this:


26 posted on 01/09/2008 11:42:55 AM PST by cogitator
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To: jjotto
Which is why any article mentioning ‘greenhouse gas’ in relation to ethanol is probably just bs anyway.

One desirable feature of biofuels is that they don't contribute CO2 to the atmosphere in the full process.

27 posted on 01/09/2008 11:44:25 AM PST by cogitator
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To: Raymann
"That said, we have a lot of little used land out west that would be perfect for growing this stuff."

ooo-kay. But where oh where is the water to grow all that tall grass going to come from?

28 posted on 01/09/2008 11:46:34 AM PST by BlueDragon (never set out to sea on a boat that has shiny pump handles...)
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To: cogitator

The trick is going to be getting farmers to grow the stuff. Now that food crops are way up in price, crops are going to be competing for the avalable crop land. And lets not forget, more farming—more pesticides and fertilizers end up in the soil, groundwaters, and streams. Furthermore, don’t think for a minute that the environmentalists aren’t going to start sceaming the minute land where some obscure species hangs out is threatened, or worse, protected federal lands.


29 posted on 01/09/2008 11:47:26 AM PST by SirFishalot
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To: cogitator

Cool!

Sounds promising. It grows on otherwise undesirable land and will not affect food prices.

Now we just gotta get past politics.

What kind of waste product does this process produce? Displacing 30% of this country’s octane would generate a LOT of waste. Will we have to deal with megatons of unusable muck that will bulk up landfills? Or does the waste product have secondary uses?


30 posted on 01/09/2008 11:56:34 AM PST by kidd
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To: cogitator

And someone posts a picture of Chernobyl to say no to nukes, and everyone feels self satisfied because we should always make energy policy based upon aberrations rather than the norm. Fascinating.


31 posted on 01/09/2008 12:00:01 PM PST by kingu (Fred08 - The Constitution is the value I'm voting for. What value are you voting for?)
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To: kidd
What kind of waste product does this process produce?

As someone else noted, you can burn some of what you don't ferment to power the fermenters. As for the fermenter residue, don't pigs eat just about anything?

32 posted on 01/09/2008 12:00:58 PM PST by cogitator
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To: kingu

I think nuclear power is safer and a better choice for our future energy needs than fossil fuels, by a long shot. In case you wondered.


33 posted on 01/09/2008 12:03:04 PM PST by cogitator
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To: cogitator
How we bend over backwards to keep the movie stars from seeing oil rigs off the coast through their telescopes,

I don't mind bending over backwards if it means reducing the occurrence of things like this:

Then you want more domestic drilling and offshore platforms connected by pipeline instead of importing most of our oil by tankers from foreign nations.

34 posted on 01/09/2008 12:03:40 PM PST by thackney (life is fragile, handle with prayer)
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To: SirFishalot

“The trick is going to be getting farmers to grow the stuff. Now that food crops are way up in price, crops are going to be competing for the avalable crop land. And lets not forget, more farming—more pesticides and fertilizers end up in the soil, groundwaters, and streams. Furthermore, don’t think for a minute that the environmentalists aren’t going to start sceaming the minute land where some obscure species hangs out is threatened, or worse, protected federal lands.”

The switch grass grows in areas you can’t till or are difficult to till. In 1999 there were about 90 million acreas in the CRP program, that is land that you and I are paying farmers not to farm.

Just getting that land out of CRP will save billions of dollars.

If you look at my posts, I am not a big believer in the ethanol economy. It is just too expensive and inefficient to convert food or biomass into ethanol.

Now if you compress the grass into pellets, you have a cheap heating fuel. One acre could provide the equivalent of about 4,000 gallons of heating oil. Pellets are easy to handle and would be about as convenient as heating with oil.

The problem with pellets is that they don’t burn in internal combustion engines. But this is a problem that should be solved in the next five years. Direct heat to electricity systems are being developed. They will make coal plants much more efficient but will also open the posibility of using pelletized fuel for transportation fuel. At this point, petroleum is in trouble and has to compete with the agricultural industry on price. This will keep the price of petroleum and biomass low. Assuming the government does not get involved.


35 posted on 01/09/2008 12:09:30 PM PST by dangerdoc (dangerdoc (not actually dangerous any more))
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To: BlueDragon

well it is grass, doesn’t need that much. Yields would prob be lower but if it’s scrub land anyway...


36 posted on 01/09/2008 12:10:20 PM PST by Raymann
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To: dangerdoc
It is just too expensive and inefficient to convert food or biomass into ethanol.

Expensive when oil is $50 a barrel, or expensive when oil is $100 a barrel?

37 posted on 01/09/2008 12:15:56 PM PST by cogitator
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To: twigs
My husband teaches in an agricultural school and he has mentioned this is as a much better choice than corn. No, its not a better choice than corn. What can be accomplished in the laboratory does not automatically translate into an economic opportunity.

First. The Cap Cost of constructing a cellulosic ethanol plant is $6+ per annual gallon. That means it would take over $600 million for a 100 million gallons per year plant. That compares to around $250 million to construct for a comparable grain based or corn based to ethanol plant.

Second, it takes 4 times the mass of switch grass or whatever biomass to produce cellulosic ethanol vs. grain based ethanol.

Third, to even come close to economically viable the cost of the biomass, switch grass, corn stover or whatever would need to be delivered to the plant site for less than $50 per ton. NO one is going to collect and transport biomass for that amount.

Fourth, if you are taking biomass from the farmers field such as corn stover, it will deprive the soil of badly needed nutrients provided by normally letting in rot in the fields. And fifth, the enzymes that will need to be developed to breakdown biomass to a form that can be fermented must be highly selective depending on the feedstock. Having so many enzymes available at a biomass cellulosic plant for use with the multitudes of different biomass feedstock will greatly add to operating cost.

The most economic thing to do with biomass if it can even bee collected efficiently is burn it to create the plant energy required to produce ethanol from grain. This will greatly reduce the cost of producing ethanol from grain based feedstick.

Economically, celullosic to ethanol is still a long way off and may never even become a reality.

38 posted on 01/09/2008 12:25:51 PM PST by suijuris
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To: RedStateRocker; Dementon; eraser2005; Calpernia; DTogo; Maelstrom; Yehuda; babble-on; ...
Renewable Energy Ping

Please Freep Mail me if you'd like on/off

39 posted on 01/09/2008 12:34:53 PM PST by Uncledave
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To: cogitator

put on your flame suit!


40 posted on 01/09/2008 12:36:14 PM PST by Uncledave
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