Researchers find corn ethanol, switchgrass could worsen global warming

[RedEarth]

Some very respected researchers today have lobbed a real bombshell into the energy public policy world: they have concluded that ethanol produced both by corn and switchgrass could worsen global warming.

In other words, Congress really blew it last year when it mandated a massive increase in biofuels (an action coated with green language but really an effort by both political parties to cater to farm states). This is also a slap at President Bush's effort to paint himself as something other than an oil man.

The new findings, led by separate teams from Princeton University and the University of Minnesota conclude that the land use-based greenhouse gas emissions would overwhelm possible emission reductions.


In other words, these studies really challenges orthodox thinking and prior assumptions about the impact of biofuels on greenhouse gas production.

These studies are unique in that they take a comprehensive look at the emissions effects of the huge amount of land that is being converted to cropland globally to support biofuels development.

"When you take this into account, most of the biofuel that people are using or planning to use would probably increase greenhouse gasses substantially," said Timothy Searchinger, the lead author of one of the studies and a researcher in environment and economics at Princeton University explained to the International Herald Tribune.

http://gristmill.grist.org/story/2008/2/7/11350/87265

Land Clearing and the Biofuel Carbon Debt

Increasing energy use, climate change, and carbon dioxide (CO2) emissions from fossil fuels make switching to low-carbon fuels a high priority. Biofuels are a potential low-carbon energy source, but whether biofuels offer carbon savings depends on how they are produced. Converting rainforests, peatlands, savannas, or grasslands to produce food crop–based biofuels in Brazil, Southeast Asia, and the United States creates a "biofuel carbon debt" by releasing 17 to 420 times more CO2 than the annual greenhouse gas (GHG) reductions that these biofuels would provide by displacing fossil fuels. In contrast, biofuels made from waste biomass or from biomass grown on degraded and abandoned agricultural lands planted with perennials incur little or no carbon debt and can offer immediate and sustained GHG advantages.

1 The Nature Conservancy, 1101 West River Parkway, Suite 200, Minneapolis, MN 55415, USA.
2 Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN 55108, USA.
3 Department of Applied Economics, University of Minnesota, St. Paul, MN 55108, USA.


http://www.sciencemag.org/cgi/content/abstract/1152747

Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land Use Change

Most prior studies have found that substituting biofuels for gasoline will reduce greenhouse gases because biofuels sequester carbon through the growth of the feedstock. These analyses have failed to count the carbon emissions that occur as farmers worldwide respond to higher prices and convert forest and grassland to new cropland to replace the grain (or cropland) diverted to biofuels. Using a worldwide agricultural model to estimate emissions from land use change, we found that corn-based ethanol, instead of producing a 20% savings, nearly doubles greenhouse emissions over 30 years and increases greenhouse gases for 167 years. Biofuels from switchgrass, if grown on U.S. corn lands, increase emissions by 50%. This result raises concerns about large biofuel mandates and highlights the value of using waste products.

http://www.sciencemag.org/cgi/content/abstract/1151861v1

About those two studies dissing biofuels

The studies do bring some rock-solid new analysis to explaining just how counterproductive most biofuels are from a climate perspective. Their abstracts say it all:


Most prior studies have found that substituting biofuels for gasoline will reduce greenhouse gases because biofuels sequester carbon through the growth of the feedstock. These analyses have failed to count the carbon emissions that occur as farmers worldwide respond to higher prices and convert forest and grassland to new cropland to replace the grain (or cropland) diverted to biofuels. Using a worldwide agricultural model to estimate emissions from land use change, we found that corn-based ethanol, instead of producing a 20% savings, nearly doubles greenhouse emissions over 30 years and increases greenhouse gases for 167 years. Biofuels from switchgrass, if grown on U.S. corn lands, increase emissions by 50%. This result raises concerns about large biofuel mandates and highlights the value of using waste products.

Increasing energy use, climate change, and carbon dioxide (CO2) emissions from fossil fuels make switching to low-carbon fuels a high priority. Biofuels are a potential low-carbon energy source, but whether biofuels offer carbon savings depends on how they are produced. Converting rainforests, peatlands, savannas, or grasslands to produce food-based biofuels in Brazil, Southeast Asia, and the United States creates a ‘biofuel carbon debt’ by releasing 17 to 420 times more CO2 than the annual greenhouse gas (GHG) reductions these biofuels provide by displacing fossil fuels. In contrast, biofuels made from waste biomass or from biomass grown on abandoned agricultural lands planted with perennials incur little or no carbon debt and offer immediate and sustained GHG advantages.

Time for a new biofuels policy.

http://climateprogress.org/2008/02/09/about-those-two-studies-dissing-biofuels/

[TechBear_Seattle]

1. I'm not sure I understand the problem

The increase in greenhouse gases will be the result of tractors, etc. converting land from other uses to the production of corn and switchgrass, and not an ongoing issue with massive tracts of corn and switchgrass producing greenhouse gases, correct?

If so, then the increase will be a one-time thing, no different than converting tillable land from one crop to another.

[Vincardog]

4. What the OP does not make clear is that it takes more energy to plan fertilize grow and harvest

energy from corn than we get back.
When you count all the energy needed to make the farm equipment it is clearly a losing proposition.

The greenhouse gas equation is not just limited to the gas emitted clearing the land it also includes the gas that the land would have removed had it not been disturbed. I believe this is the cost the OP not to clearly wants to take into account.

[TechBear_Seattle]

6. Ah, got it. n/t

[Viking12]

7. Not quite.

It's the land-use change in and of itself that contributes increased GHG, not just the means to change the land. There's a growing body of literature demonstrating that the more diverse the flora of an ecosystem, the more carbon sequestered.

[Radical Activist]

2. What if existing crop land is used?

Then its not a problem? What if you're using land that was once use to grow corn and using swtichgrass instead, which takes fewer resources to grow and absorbs more carbon?

[NickB79]

9. Then you're left with less land for food production

And that's a whole other problem related to biofuels.

[madrchsod]

3. there is an assumption that the land and climate

can sustain the levels of productions needed for both fuel and food. we have had drought cycles in the major corn belt of this country and we are due for another...it would be far better to produce ethanol for the production of food not to put it in our automoblies

[unpossibles]

8. because most of that food gets wasted on livestock. nt

[msongs]

5. the welfare for farmers lobby will not like this report nt

[tom_paine]

10. Of course it would. That's why it's being sold to us.

It will also help trim the human herd as we stuff food into our gas tanks instead of into, as the Bushies view them and us, Inferiors, and Useless Eaters.

Biofuels, even if we liquidated every piece of food on this Earth plus swicthgrass, would generate no more than 20% of our petroleum consumption, and that is a generous estimate, so the math shows us right from the start it's a pointless exercise from the jump.

But it's a nice scam and will put a lot of money into the hands of the Big Agro Bushies.

End of story. End of species.

[Nihil]

16. Tut, tut ... don't you understand?

> But it's a nice scam and will put a lot of money into the hands of
> the Big Agro Bushies.
> End of story. End of species.

Whoever dies with the most toys is the winner!

(Or maybe not ...)

[Fledermaus]

11. Searchinger study examined a corn production case that is not relevant to U.S. corn ethanol

The corn ethanol growth figures used by Searchinger correlate to 30 billion gallons a year of production by 2015. However, the new federal renewable fuel standard caps corn ethanol production at 15 billion annual gallons.

[Fledermaus]

12. new acres of U.S. corn cultivation in 2008, 60 percent came from soybeans

97 percent of which goes into animal feed. Because of the DGS coproduct, only a fraction of an acre of soybeans are needed to replace an acre of corn.

[NickB79]

13. This study didn't focus exclusively on the US

"Using a worldwide agricultural model to estimate emissions from land use change, we found that corn-based ethanol, instead of producing a 20% savings, nearly doubles greenhouse emissions over 30 years and increases greenhouse gases for 167 years."

[Fledermaus]

14. The researchers base their scenarios on an assumption virtually all observers believe is unlikely,

The researchers base their scenarios on an assumption virtually all observers believe is unlikely, 30 billion gallons per year of corn ethanol.

Accrding to the studies, this would, bring about 10.8 million hectares of new cropland into cultivation, primarily in Brazil, China, India and the U.S.

15 billion annual gallons is generally regarded as the peak, and that is why it is embodied in the federal fuels standard. Searchinger study examined a corn production case that is not relevant to U.S. corn ethanol production.

[losthills]

15. What's special about the US?

Oh yeah, government subsidies.....

[jpak]

17. ugh - this applies to any crop grown on land converted to agriculture: butter beans or biofuels

If you convert Amazon/Malaysian/Indonesian rain forest to grazing land, there is a net transfer of carbon from that converted land to the atmosphere.

If you convert natural US prairie/forest to conventional agriculture - for any crop , there is a net transfer of carbon from that converted land to the atmosphere.

If, however, you convert mid-west US land currently under conventional corn/soybean agriculture *back* to natural prairie and use natural prairie grasses for biofuel (fuel pellets or liquid fuels), there will be an net transfer of carbon from the atmosphere to the restored prairie soil carbon pool.

In that case, biofuels will be carbon neutral or carbon negative...