Thursday, February 7, 2008

Energy Biofuel and Carbon Emmisions

Two new studies are making their way across the web this week examining the environmental impact of the manufacturing biofuels.

Sites are interviewing one of the authors, Joseph Fargione of The Nature Conservancy, to get an authoritative viewpoint. At first glance his arguments appear valid.

"Carbon is the main building block of life, so plants are 50 percent carbon by dry weight," Fargione said. "So when you're looking at a rainforest, there's tons and tons of carbon stored in the plant biomass and in the soils."

When land is cleared either by cutting trees down or by burning, much of that stored carbon is released into the atmosphere.

"Fire releases the carbon directly, as carbon dioxide, and decomposition, when plants decay, that also releases the carbon as carbon dioxide," Fargione explained. "And this carbon dioxide goes into the air as an important greenhouse gas and contributes to global warming."

Large amounts of carbon in these ecosystems are released each year through deforestation and other land conversion.

"Over the last 150 years, 25 percent of our carbon emissions have come from land clearing," Fargione said.

Biofuels from crops such as corn, sugarcane, soybeans and palms require land to grow on. Most of this land must either directly or indirectly come from the destruction of natural ecosystems, because "right now we're asking the world's farmers to feed 6 billion people, and they're doing it on some fixed amount of land," Fargione said. "And if we're also going to produce energy, that requires new land, and that new land has to come from somewhere."

Clearing natural ecosystems, either for farming food crops or growing biofuel crops, creates what Fargione calls a "carbon debt." The initial clearing of the land releases an amount of carbon dioxide that could take decades or centuries to make up for by using biofuels. BioFuels Can Be Bad
Can be bad, OK, he has a point, if you clear cut a rainforest, and BURN it, of course you will get a Carbon Debt in the process. Is anyone actually considering this insane tactic? If you are stop it, please. Domestic production here in the US will be faced with no such problem.

Other arguments by Fargione are also overblown. Consider this quote from The New Scientist.

The idea makes intuitive environmental sense – plants take up carbon dioxide as they grow, so biofuels should help reduce greenhouse gas emissions – but the full environmental cost of biofuels is only now becoming clear.

Extra emissions are created from the production of fertiliser needed to grow corn, for example, leading some researchers to predict that the energy released by burning ethanol is only 25% greater than that used to grow and process the fuel.

...When the carbon released by those clearances is taken into account, corn ethanol produces nearly twice as much carbon as petrol.

The New Scientist: Biofuels emissions may be 'worse than petrol'

I can agree with this one. Anyone that argues we should be using Food crops for fuel production is hurting the cause. One only need look at the effects that ethanol has had on corn pricing as of late, for a practical reason why it is a bad idea. Corn and other food products require vast amounts of fertilizer and farm equipment causing an increasing amount of carbon emissions, there is a an environmental reason. However, there are crops that do neither.
The U.S. Department of Energy (DOE) believes that biofuels—made from crops of native grasses, such as fast- growing switchgrass—could reduce the nation's dependence on foreign oil, curb emissions of the "greenhouse gas" carbon dioxide, and strengthen America's farm economy.
Biofuels from Switchgrass: Greener Energy Pastures
Switchgrass is a renewable crop, requires planting every 10 years, and uses heavy equipment only during harvest. It also does quite well with little to no fertilizer. These facts are ignored by the study. Instead focusing on worst case scenarios and painting the entire BioFuel industry in a negative light.

Let me be clear about this. Biofuels are not a longterm solution. They are a stopgap measure intended to reduce Co2 emmisions and reduce the dependence on foreign oil.

Getting rid of the combustion engine will take time and courage. Two things that scientist and political watchdogs will tell you we sorely are lacking.

We cannot wait for it, We must act now to reduce emissions and consumption of finite resources we have no control over. Lest we continue down this slippery slope that leaves our children and grandchildren in a very dirty and very violent world.


Update: I have sent off an email to Mr Fargoine, hoping to get clarification.
He did reply with copies of the two reports. And this response.
The problem with diverting cropland to fuel production is that people have to eat, and so land is converted to food production elsewhere. This is occurring as US farmers switch from soy to corn, increasing soy prices which spurs deforestation of Amazonian rainforest for soy production.

We simply cannot ask the world's farmers to produce food for 6 billion people, and also ask them to produce energy, without using additional land. That land has to come from somewhere. Unfortunately, much of it is coming from natural ecosystems.

What most people don't realize is how much carbon is stored in natural ecosystems. There is three times as much carbon locked up in plants and soils as there is the atmosphere. Land use change cause 20% of our carbon emissions. Any policy to fight climate change must take land use into account, or it won't work.
Unfortunately, the press ignores the biomass ethanol numbers and focuses on the worst case numbers. LArgely because the study emphasizes those points as well.

Here are the two pieces of information that are most important to me.
Barring biofuels produced directly on forest or grassland
would encourage biofuel processors to rely on existing
croplands, but farmers would replace crops by plowing up
new lands. An effective system would have to guarantee that
biofuels use a feedstock, such as a waste product or carbon-
poor lands that will not trigger significant emissions from
land use change.
SOM Text
Tables S1 to S3
Appendix A to F
17 October 2007; accepted 28 January 2008
Published online 7 February 2008; 10.1126/science.1151861
Take a look at this chart and pay special attention to the far right.
Materials and Methods
Tables S1 and S2
8 November 2007; accepted 24 January 2008
Published online 7 February 2008; 10.1126/science.1152747

This is exactly what I am talking about. This study should be used to promote prairie biomass ethanol instead of condemning it along with corn ethanol.

Special thanks to Joe for providing the data that helps clear this up. Although I think he should emphasize these points a little better to the media. Even with pointed questions, I had to dig into the reports instead of getting a straight answer.


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