Time to Move to a Second Generation of Biofuels
Two studies published in the journal Science last week have reinforced the urgency of moving quickly to a second generation of biofuels. The two studies, one produced by a team of researchers at the University of Minnesota, and the other led by researchers from Princeton University, found that biofuels can actually produce more carbon dioxide emissions than they save—if they force natural habitats to be converted to cropland, releasing the carbon contained in trees and grasses and in the soil they grow on.
The gist of the two reports? Clearing land for biofuel crops—especially when it involves the loss of forests, peatlands, and grasslands that are nature’s premier method of carbon capture—is a bad idea. The reason is clear: the world’s forests and grasslands contain an enormous reservoir of carbon, which will add to greenhouse warming if it’s released to the atmosphere. Even switchgrass, if grown on land now being grown to produce corn, could increase emissions by 50 percent if it forces the clearing of new land to grow food.
The Science papers, covered in the Wall Street Journal, New York Times, Los Angeles Times, and virtually everywhere else, blared such headlines as “Biofuels Deemed a Greenhouse Threat.” And it’s shaking the scientific community into high gear. According to Washington Post writer Juliet Eilperin, senior scientists responded to the new studies by sending a letter to President Bush and House Speaker Pelosi urging them to reconsider their energy policies.
“While politicians in the U.S. and Europe have tried to craft policies dictating that new biofuels will not come at the expense of clearing land, the papers show that sometimes land conversion is often an indirect result of this expansion,” the 10 scientists wrote. “There is an urgent need for policy that ensures biofuels are not produced on productive forest, grassland or cropland.”
These studies provide important new evidence to reinforce a message that the Worldwatch Institute produced in its pioneering 2007 book, Biofuels for Transport: “Because increases in the land area used to produce feedstocks can result in large releases of carbon from soil and existing biomass, they can negate any benefits of biofuels for decades.” Now, it turns out, the expansion of some biofuel crops could actually make the world’s climate problem worse.
It is time for policymakers in Washington and around the world to reduce subsidies to food-based biofuels and increase them for biofuels that will truly reduce greenhouse gas emissions and address other environmental problems as well. As one of the Science studies concluded, “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.”
Last autumn, Worldwatch worked with the Sierra Club on the report, Destination Iowa: Getting to a Sustainable Biofuels Future, which sets forth recommendations on how the state of Iowa, a leading U.S. ethanol producer, could do just that. Some of the report’s suggestions for moving toward a more sustainable biofuels future include:
- Accelerate development of cellulosic biofuel technologies and the infrastructure to harvest, transport, and process the new crops.
- Provide incentives for low or no-till agriculture, the planting of cover crops, and the creation of riparian buffer zones.
- Support farmers who want to invest in sustainable fuel crops such as perennial grasses or fast-growing trees.
- Reduce tax subsidies for food-based biofuels and increase subsidies for fuels with a low-carbon footprint, such as waste and cellulose-derived biofuels.
- Increase investment in solar, wind, and other forms of renewable energy that provide greater climate benefits than today’s biofuels do.
The main message the world should take from the new biofuels studies is that the current world agricultural system, like the world energy system, is unsustainable. And unless it’s fixed, rising production of both fuels and food will wreak havoc.
A recent article published in Environmental Health Perspectives pointed out that high levels of meat consumption are also leading to land clearing and rising greenhouse emissions—much the way that corn-based biofuel does. In just the last five months of 2007, more than 3,000 square kilometers of forest has been cleared in the Amazon to make way for cattle ranches and for soybeans used for animal feed.Christopher Flavin is president of the Worldwatch Institute, an environmental research organization based in Washington, D.C.