Two new studies published in Science (here and here) suggest that the use and production of biofuels substantially increases greenhouse gas emissions, particularly if such fuels are produced from food crops. Unlike prior studies, these reports sought to account for the loss of carbon storage due to the land conversion necessary to grow biofuel feedstocks. Once this factor is taken into account, both studies found, conversion to biofuels are big greenhouse losers. As the New York Times reported:
The destruction of natural ecosystems — whether rain forest in the tropics or grasslands in South America — not only releases greenhouse gases into the atmosphere when they are burned and plowed, but also deprives the planet of natural sponges to absorb carbon emissions. Cropland also absorbs far less carbon than the rain forests or even scrubland that it replaces.The actual studies are not all bad news for biofuels, however. Both suggest that the production of biofuels from waste products could produce greenhouse gas reductions, and one of the studies suggests potential GHG emission savings from the production of biofuels from perennial grasses. Neither study has anything good to say about corn-based ethanol.Together the two studies offer sweeping conclusions: It does not matter if it is rain forest or scrubland that is cleared, the greenhouse gas contribution is significant. More important, they discovered that, taken globally, the production of almost all biofuels resulted, directly or indirectly, intentionally or not, in new lands being cleared, either for food or fuel.
“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, lead author of one of the studies and a researcher in environment and economics at Princeton University. “Previously there’s been an accounting error: land use change has been left out of prior analysis.”
If we want to know the full environmental toll of biofuels there are additional factors to consider. Particularly when biofuel production requires the use or conversion of cropland, as with corn-based ethanol, these costs include increased water use (which is becoming a problem in parts of the midwest) and the loss of migratory bird habitat. The bottom line is that the energy "solution" most favored by the political class is no solution at all.
But the two studies conflict on their other key conclusion. One study, with the lead author at the Nature Conservancy, said: "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."
In contrast, the other paper authored at the Woodrow Wilson school of public policy said "But if American corn fields of average yield were converted to switchgrass for ethanol, replacing that corn would still trigger emissions from land use change that would take 52 years to pay back and increase emissions over 30 years by 50%."
In case you missed it, the latter paper sets up a huge straw man. No one serious about cellulosic crops thinks they should be substituted for food crops. The entire point is that switchgrass can be cultured on lands not amenable to corn!
Unsurprisingly, the NYT (and most other media outlets) glossed over the conflict to find the lowest common denominator: biofuels are bad. I'm a researcher in the area, and I agree wholeheartedly that corn ethanol doesn't make a lot of sense. But, lignocellulosics have legitimate potential.
That is one bottom line, with the emphasis on political preference. If we look instead at the long-term biofuel alternatives preferred by the R&D community (such as lignocellulosic ethanol and biodiesel derived from algae grown on desert lands), then the political emphasis on biofuels from subsidized food crops is quite distant from the bottom line. Studies of the long-term potential of these biofuel alternatives and how food-crop-based biofuels should or should not be used to bridge to a better biofuel future are more needed than incomplete media glosses on the effects of biofuel usage on greenhouse gas emissions.
How can I feel smug and superior as I drive around my bio-fuel converted beater Toyota, covered with political bumper stickers if this is true? Dammit....I am superior to the rest of you. I just know it.
This isn't quite true. The paper in Science that I criticized for its straw-man dismissal of lignocellulosics (a pun!) was rooted in economic analysis. Economic modeling isn't my speciality so I can't say one way or another if the models are any good, but at least they seem to be trying.
If I remember right, there has been a slight displacement of soybeans for more corn, but the bigger effect has been a decrease in corn exports. The corn going into ethanol is largely taken from what used to be exported.
That doesn't deal with the energy balance of farming corn for ethanol, but it does suggest that we can expand acreage without getting into virgin lands.
That is a very good point. Turning an existing Iowa corn field into ethanol will clearly have less GHG impact than cutting down some of the Amazon and planting corn for ethanol.
As noted earlier, that's true only if you assume that no one will fill the economic void left by the one less Iowa cornfield by planting their own.
That might be a plausible scenario with one field, but the gap of hundreds? No one will fill that? Really? How would you stop them?
"Rumblings in the literature"???? Cite please!
You've yet to realize the flaws in your argument that the study should have considered increased food prices- even though myself and anonthu have pointed it out. If you are converting land, you are creating farms, and if you are creating a new farm for biofuel, you obviously aren't using an farm that was used for food. And if you aren't using a farm to create biofuel that was previously used for food, you aren't diverting food. Thus, it would have been disingenious for the scientists doing this study to mention diversion of food, when the biofuel production method that they are criticizing for environmental impact will not divert food.
Now we're doing the corn-factory thing. In our area, the only new ground broken is for ethanol plants.
So if we're going to do something other than burn food, it isn't going to be done in traditional agriculture areas.
It will have to be in places where farming is not currently being done. And why isn't it being done? Generally, lack of water. Hell, the Colorado still has some water in it, I think. Go for it.
Exactly. And a strong argument against food-crop biofuels either way. Raise food price with lower GHG impact (diversion) or raise GHG impact with minimal impact on food price (conversion).
As noted earlier, that's true only if you assume that no one will fill the economic void left by the one less Iowa cornfield by planting their own.
"Planting your own" will still be either conversion or diversion...