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http://www.scienceblog.com/cms/scie...osts-producing-switchgrass-ethanol-15626.html


Scientists Determine Farm Costs of Producing Switchgrass for Ethanol
Submitted by BJS on Thu, 2008-03-06 09:22.

According to Perrin and Vogel, this study is the most comprehensive one completed to date assessing the economic costs of producing switchgrass biomass on commercial fields. The team contracted with 10 farmers in Nebraska, North Dakota and South Dakota to commercially grow switchgrass for five years, starting in 2000 and 2001. Throughout the study, the farmers recorded all costs for producing switchgrass biomass, from seed and fertilizer expenses to equipment and labor costs. Total baled biomass yields were recorded for each farm.

On average, switchgrass production costs were $60 per ton. Two farmers with previous experience growing switchgrass were able to limit production costs to $39 a ton. They were among a group of five farmers whose production costs were $50 or less per ton. That's something farmers elsewhere could probably achieve as they, too, gain production experience with switchgrass, the researchers suggest. Based on the $50-per-ton figure, and assuming a conversion efficiency of 80 to 90 gallons per ton, the farmgate production cost of cellulosic ethanol from switchgrass would be about $0.55 to $0.62 per gallon


Switchgrass
 

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so that would probably translate to 1.85 a gallon????
 

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It doesnt factor in the cost of making the ethanol, but does lower the price of producing the switchgrass which in turn reduces the overall price of ethanol.
 

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Starting with $0.55 to $0.62 per gallon, you have to add:

*the farmer's profit

*the cost to convert it to ethanol

*the ethanol producer's profit

*the cost to get it to where it will be blended with the gasoline

Still, even after adding all of that, and then considering the lower energy level of ethanol, I'll bet you come out ahead of the wholesale price of gasoline.
 

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Considering how inexpensive it is to make vehicle run on E-85, and the low cost of switchgrass production, I have to think Ethanol must be part of the solution to renewable energy sources.
 

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The question I'm left with is: The "farmgate production cost" of corn-based ethanol is about $??? per gallon?

Without that information to compare the numbers here don't mean much to me. I'd like to be able to compare the "raw" cost of switchgrass to the current "standard" of ethanol, corn, then we can guess a price per gallon.

This article is a bit too focused on the results of the switchgrass tests without providing us with the comparison info we really need to make a judgement on whether or not switchgrass is a viable alternative to corn. And other things I guess should be taken into consideration -- for instance, if corn production benefits from subsidies that switchgrass farmers cannot take advantage of (yet) because switchgrass is not a food product, or something like that.
 

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How many acres of land would have to be planted to harvest enough to meet demand? (competition with food crops affecting prices?)

How much water is needed for this process? (affects on water supply)

How many forests have to be cleared to make room for this stuff, releasing all that carbon into the atmosphere? (higher timber costs?)

How much fertilzer runoff will contribute to dead zones in the Gulf Of Mexico? (higher seafood prices?)

Are there crop rotation requirements to maintain adequate soil balances?
 

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If I remember correctly, switchgrass can be grown effectively on marginal land meaning farmers can exploit land that can't be used profitably for food production. It's a win-win.
 

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How many acres of land would have to be planted to harvest enough to meet demand? (competition with food crops affecting prices?)

How much water is needed for this process? (affects on water supply)

How many forests have to be cleared to make room for this stuff, releasing all that carbon into the atmosphere? (higher timber costs?)

How much fertilzer runoff will contribute to dead zones in the Gulf Of Mexico? (higher seafood prices?)

Are there crop rotation requirements to maintain adequate soil balances?
The reason why they want to make ethanol from switchgrass is because it grows everywhere (low quality land) and doesn't require much water or fertilizer. They can probably grow the stuff on fallow land that's in rotation, but that's just speculation. Corn is a very high input crop, it takes lots of water and fertilizer to grow. I don't think ethanol is THE answer because it takes a lot of water to make, even though they are slowly getting more water efficient. But if we can start to lower our demand for petroleum every year and replace it with biofuel of some sort, we'll be in pretty decent shape.
 

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monkeylizard, I thought the main point of switchgrass was that it was a tough plant that required little or no fertilizer or water and could be grown in places traditionally unsuitable for normal crops. I also assume that there are plenty of natural grasslands around the U.S. that do not require "rotation".

If anything I would think a natural diversity of plant life in the planted area might be required - something typical crops like beans or corn cannot tolerate - for instance, some other "weeds" that grow alongside (in between) the grasses that keep a natural balance in the soil and grow strong during the off season of the switchgrass ---- if attempts are made to make the switchgrass a "monoculture" in the area it is harvested in for ethanol (no other "weeds" allowed), then problems could arise.

I look at my own lawn, where I use no fertilizer or weed treatments. Dozens of "weeds" grow in with the native grasses, and during the winter they dominate, only to give way to the grass when it heats up. The typical crop farming method used for corn, etc., does not allow for the growth of other plants in the planted rows. That kind of monoculture mini-ecosystem opens up the farmed plants to all kinds of problems with bugs and diseases and makes crop rotation necessary.

My understanding with the switchgrass was that it was supposed to be something that would be grown with much less of a structured agricultural "crop row" method, but in practice (and here in testing), I would not be surprised if they tried to grow for maximum output and planted monocultures of switchgrass and end up exposing themselves to many of the problems of traditional farming.
 

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How many acres of land would have to be planted to harvest enough to meet demand? (competition with food crops affecting prices?)

How much water is needed for this process? (affects on water supply)

How many forests have to be cleared to make room for this stuff, releasing all that carbon into the atmosphere? (higher timber costs?)

How much fertilzer runoff will contribute to dead zones in the Gulf Of Mexico? (higher seafood prices?)

Are there crop rotation requirements to maintain adequate soil balances?
Less than corn.

Less than corn.

None. The Great Plains have always naturally been grassland. They have never been covered with forests.

Less than corn.

No.
 

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I think these are the interesting figures (I've made mistakes with my math before, so if you catch any, please point them out.):
From the article, 80-90 gallons of ethanol per ton of switchgrass.
From this article http://www.harvestcleanenergy.org/enews/enews_0505/enews_0505_Cellulosic_Ethanol.htm, currently yields are typically 5 tons of switchgrass per acre and in theory 12.4 tons per acre is reasonable. That's 400 (5 tons times 80 gallons per ton) to 1116 (12.4 tons times 90 gallons per ton) gallons of ethanol per acre.

For comparison, this article says corn ethanol yields are 354 gallons per acre.
http://www.sarid.net/technology/051027-food-fuel-compete.htm

Since switchgrass is cheaper and less resource and fertilizer intensive to grow than corn, it looks like switchgrass clearly beats corn ethanol.

On the other hand, the US uses the equivalent of something like 190 billion gallons of ethanol in petroleum right now. To replace that with switchgrass ethanol, even at maximum yield 1116 gallons per acre, requires 170.25 million acres or 266,000 square miles, or over 7% of the total US land mass. At minimum yield 400 gallons per acre, we'd need to cover almost 20% of the country with switchgrass farms.

A very good improvement, yes. A total solution, no.
 

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I think these are the interesting figures (I've made mistakes with my math before, so if you catch any, please point them out.):
From the article, 80-90 gallons of ethanol per ton of switchgrass.
From this article http://www.harvestcleanenergy.org/enews/enews_0505/enews_0505_Cellulosic_Ethanol.htm, currently yields are typically 5 tons of switchgrass per acre and in theory 12.4 tons per acre is reasonable. That's 400 (5 tons times 80 gallons per ton) to 1116 (12.4 tons times 90 gallons per ton) gallons of ethanol per acre.

For comparison, this article says corn ethanol yields are 354 gallons per acre.
http://www.sarid.net/technology/051027-food-fuel-compete.htm

Since switchgrass is cheaper and less resource and fertilizer intensive to grow than corn, it looks like switchgrass clearly beats corn ethanol.

On the other hand, the US uses the equivalent of something like 190 billion gallons of ethanol in petroleum right now. To replace that with switchgrass ethanol, even at maximum yield 1116 gallons per acre, requires 170.25 million acres or 266,000 square miles, or over 7% of the total US land mass. At minimum yield 400 gallons per acre, we'd need to cover almost 20% of the country with switchgrass farms.

A very good improvement, yes. A total solution, no.
And in that you found the rub with ethanol. The US cant "grow" enough of our fuel supply at current consumption rates. Now if we could grow enough to offset the amount of oil we import (especially from the less than friendly countries) that is a step in the right direction.
 

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I agree that ethanol will only be a part of the solution, and not the entire solution. But I also think that it is a great first step.

I think the long term solution will rely heavily on electric cars (and the batteries that they require). Hopefully huge advances in energy storage are on the horizon. Ideally, we would move away from chemical storage and toward mechanical or capacitor-type storage (I know I'm not using the right terms, but you know what I mean) because chemical storage means that we are just depleting some other resource.

I also think conservation has to play a big part. We simply need to be more efficient, and I don't necessarily mean driving smaller cars (at least not entirely). Living closer to where you work is a good start. I frankly don't understand why some commute for hours to work everyday. That is ridiculous, IMO.
 

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I have this awesome idea.......

kill the 35MPG law instead force all gas to be E10 then in 2 years jump to E20 gas.........

Thats a 20% reduction in gas consumption and its done while producing US jobs and helping the US economy although these companies will likely out source anyways as soon as they get the chance.
 

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Starting with $0.55 to $0.62 per gallon, you have to add:

*the farmer's profit

*the cost to convert it to ethanol

*the ethanol producer's profit

*the cost to get it to where it will be blended with the gasoline

Still, even after adding all of that, and then considering the lower energy level of ethanol, I'll bet you come out ahead of the wholesale price of gasoline.
The way I read it the cost to convert to ethanol was included.

A couple of hidden benefits are drastically reduced fertilizer usage, no pesticides needed and stopping errosion that comes with traditional farming.
 

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I have this awesome idea.......

kill the 35MPG law instead force all gas to be E10 then in 2 years jump to E20 gas.........

Thats a 20% reduction in gas consumption and its done while producing US jobs and helping the US economy although these companies will likely out source anyways as soon as they get the chance.
What the hell, are you patriotic or something? We'll have none of that around here!
 

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In regards to crop rotation, a few years of switchgrass would revive land overfarmed for grains and such. Also remember, with good rains you can get 3-6 cuttings a year on switchgrass and it can be processed just like corn silage.
 

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One thing I dont understand is we have E10 right now at many stations - from what I understand the 'summer blend' wont have E10 anymore.......why? Just keep it the same year round.
 
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