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Not so green: corn ethanol reduces the soil carbon, increasing emissions and possibly contributing to warming. This effect is worsened if the leaves are removed for biofuel production, as some have suggested.  (Source: Don Hamerman)

Professor DeLucia of the University of Illinois and his colleagues have completed a massive new study, showing just how bad for the environment corn, and especially sugarcane, ethanol may be. It also shows grass ethanol can be very beneficial to cutting carbon, on the other hand.  (Source: Don Hamerman)

Replanting corn and sugarcane land with biofuel grass can help undo the damage done by these crops, the study suggests.  (Source: Don Hamerman)
A new study shows that switching from corn ethanol to grass may have great benefits

The ethanol business is a booming market, buoyed by several years of high gas prices.  While hampered somewhat by falling petrol costs, the market is seeing support from big investors like GM and is producing millions of gallons fuel yearly, with pumps expanding across the country.

However, while most agree that moving away from reliance on insecure, depletable oil is a good thing, there are also significant downsides to corn ethanol production, the current primary form of ethanol produced.  As discussed previously at DailyTech, corn ethanol is cited for higher food costs.  Additionally, it may not be as green from a carbon perspective as people think.

Companies like Coskata are looking to use alternatives such as quick growing grasses or wood waste to fuel their ethanol production.  Now a new study shows that not only does such production help to normalize food prices, it also helps cut down on excess atmospheric carbon.

A study from the University of Illinois confirms that some sources of biofuels can actually increase emissions of carbon dioxide, while others can decrease them.  The key is what you grow and where you grow it. 

The study compiled soil carbon information from dozens of other studies in order to get the big picture.  What it observes is that the amount of carbon that exists in the soil is increased by letting decomposing plant matter sit and eventually be absorbed into the earth, while tilling and plowing decreases the carbon in the soil, releasing it into the atmosphere.

Explains Evan DeLucia, a professor of plant biology at Illinois, "From the time that John Deere invented the steel plow, which made it possible to break the prairie sod and begin farming this part of the world, the application of row crop agriculture to the Midwest has caused a reduction of soil carbon of about 50 percent  The biggest terrestrial pool of carbon is in the soil. The top meter of soil holds more than three times the amount of carbon stored in either vegetation or the atmosphere, so if you do little things to change the amount of carbon in the soil it has a huge impact on the atmosphere and thus global warming."

Corn ethanol increases emissions, according to the study, because corn must be constantly replanted, and replanting requires tilling the fields.  Switchgrass, Miscanthus, and other fast-growing grasses, however, require no tilling and can grow wild, greatly increasing the soil's carbon and decreasing emissions.

Furthermore, these sources have more carbon density than corn, so once cost-efficient ways are created to process them, cellulosic ethanol should require much less land to produce than corn ethanol.

The study is significant, says Professor DeLucia as currently 20 percent of the U.S.'s corn crop goes to ethanol.  He describes "so we began with the hypothesis that it might be good for soil carbon to put a perennial biofuel crop on the landscape instead of corn."

From there they delved into massive amounts of information on soil carbon levels on land growing corn, sugar cane, Miscanthus, switchgrass and native prairie grasses, taking into consideration many factors.

They found that sugarcane, used greatly by Brazil's ethanol industry, is the worst offender when it comes to biofuels.  Sugarcane planted on native land slashes the carbon content, releasing vast amounts of carbon into the air.  Whereas perennial grasses add to soil carbon's base level each year, sugarcane land would require a century just to recover to the base level.

Corn showed similar, but lesser problems.  These problems could be alleviated somewhat by leaving more of the corn stover (plant waste) on the field, but the carbon was still cut significantly.

Losses from the initial planting of Miscanthus, switchgrass or native perennial grasses by on converted corn or sugarcane land took very little time to be neutralized thanks to great yearly gains in soil carbon.  Professor DeLucia states, "Consistent with our hypothesis, the perennial feedstocks like Miscanthus and switchgrass start building soil carbon very, very early on.  From a purely carbon perspective, our research indicates that putting perennial biofuel crops on landscapes that are dominated by annual row crops will have a positive effect on soil carbon."

These conclusions, he says, walk the study unintentionally "seems to walk you right into the food for fuel debate".  But he says that it just makes sense to plant grasses as biofuel feedstocks, even from a purely carbon-conscious perspective.

The research will be featured in the journal Global Change Biology Bioenergy next month.



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RE: Keep focused
By BansheeX on 12/8/2008 2:03:15 PM , Rating: 2
Even if OPEC didn't cut production, we have a general problem where major oil fields responsible for the bulk of production are drying up AS world demand for oil increases. There haven't been any new discoveries sufficient to meet that new demand. If supply expansion peaks, but demand outpaces it, the price trend has to stay up. Add unprecedented domestic money supply increases, and that spells worse news for us. If the dollar loses its reserve status, its all over, we can't export our inflation anymore and it all comes home to roost. Just a few years ago, oil was $20 a barrel and gold was $275. It is currently much higher than that and poised to liftoff again in dollar terms after these hedge funds stop imploding. The Fed is the only one left willing to buy up government debt (bonds) at these interest rates. The money they create to do so is backed by no new labor or product, unlike foreign savings that was part of the mixture before. That usually precedes a hyperinflationary spell, we're certainly not the first ones to have tried paying off our debt with a printing press.


RE: Keep focused
By Spuke on 12/8/2008 2:48:52 PM , Rating: 2
quote:
If the dollar loses its reserve status, its all over
Yep, I just bought three 30k gallon propane tanks, a huge pellet boiler, a 15kW solar system, and a 10kW propane generator. We've been buying extra food and supplies for the past 3 years. When things implode, we'll be ready to weather the storm for quite a few years.


RE: Keep focused
By Ringold on 12/8/2008 8:44:02 PM , Rating: 2
quote:
The Fed is the only one left willing to buy up government debt (bonds) at these interest rates.


.. eh? The funds rate has been trading way below the target rate for quite a while now. The fed is buying a bunch of crap, but treasuries on the open market? No, I think thats genuine demand by genuine people who can't seem to find anything better to do with their money. With all other asset classes collapsing, they'd rather practically pay the government to hold their money for them in short term instruments than risk it elsewhere.

You'll be right about some of that in another year or two, when the velocity of money picks back, but not yet. The bonds might go back to sane yields just as soon as the equity markets stop declining.

I still maintain that oil was supply and demand driven earlier this year at the peak just as it is now. Demand collapsed, and so has the price. It can't fall too much lower, because huge portions of the worlds oil fields has costs right about where it is now, and crack spreads for refineries are negative. Not sure what any of that has to do with inflation; just dwindling oil reserves and increasing costs at tapping new ones. Gold is also interesting as a proxy for many things, but it's also unreliable; it has every reason to be going up, but fails to do so. The long bond and long corporate bonds could be used to look ahead at inflation expectations, but they're also not showing anything too scary. That doesn't mean inflation wont shoot up (I think, like you, that it will), but Volcker put us in a recession last time to slay the beast.. maybe the old man can talk Obama in to doing it again if necessary. Either way, I don't see how we could speak with such certainty about it yet, things are too unclear as yet. For now, we're deflating.


RE: Keep focused
By BansheeX on 12/9/2008 11:22:45 PM , Rating: 2
Few people could explain market behavior as being rational right now, in any sense. I don't define deflation/inflation as prices, but money supply decreases/increases. I see falling prices from deleveraging, not deflation. I also think there is a lag effect to the inflation being created now, it simply hasn't gotten into the system yet, but it's there. Once it does, I expect stocks to soar nominally, commodities to outpace them, and the dollar to drop like a stone.

You mention demand destruction in oil. I haven't seen any of that personally. I see the same amount of traffic, I buy with the same regularity. I just think the paper futures market was a bubble. I don't blame the speculators, I blame the fact that they had all that funny money to pump into it. That's what people don't realize, inflation can go anywhere. Stock prices, home prices, assets, goods, bonds. It's a very confusing variable to have running amok. That the Fed doesn't include all consumer prices in the consumer price index makes people oblivious. Nobody complained on the way up, they only thought it was bad on the way down. But going down is the symptom, the abnormal rise that preceded it was the problem. No different from drug high and withdrawal.


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