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Can't See the Forest for the Biofuels
By Brandon Keim August 16, 2007 | 1:00:00 PMCategories: Climate, Energy, Environment, Sustainability

According to a new study, cutting down forests to grow crops for fuel causes more environmental damage than using biofuels can ever offset.

It's a sobering message at a time when energy crops, once a hippie dream, have gone mainstream green. Around the world, governments and industries have pledged to replace climate-fouling fossil fuels with fuel made from plants. But is it possible that we can't see the CO2 forest for the trees?

Writing in the journal Science, Renton Righelato of the World Land Trust, a British conservation group, and Dominick Spracklen, an environmental researcher at the University of Leeds, compared the carbon dioxide savings offered by using land for biofuel crops or forests.

The worst practice for the environment, they found, is making space for biofuel crops by clearing forests. Inevitably, forests absorb more CO2 than is saved by biofuel crops grown where they once stood.

"People feel they're saving the planet. They're not. The real issue we should be concerned with is reducing consumption and improving fuel efficiency," said Righelato. "Biofuels are essentially being used as a way of avoiding the real problem: reducing the use of fossil fuels."

Biofuel demand from places like Europe and North America has prompted deforestation in the developing world.

The European Union has pledged to replace 20 percent of transport fuels with biofuels by 2020. By that time, the United States plans on using biofuels for about 15 percent of transportation power.

To meet those goals with today's technologies, half of US and EU food crop land would be devoted to energy crops, estimates the International Energy Authority. That's not about to happen, so the demand is being displaced onto the developing world -- with potentially disastrous results.

In Indonesia, for example, environmentalists estimate that foreign biofuel demand will drive energy companies to clear the country's remaining peat rainforests, a valuable CO2 sink. The resulting slash-and-burn could release 50 billion tons of CO2 -- nearly a decade's worth of US greenhouse emissions -- into the atmosphere.

Brazil has designated nearly half a billion acres of forests, grassland and marshes as "degraded" areas suitable for conversion to farming. While the entire Alaska-sized area won't be cleared, much of it could be planted with soybeans, the staple of that country's biofuel efforts.

By correlating soybean prices with satellite images, NASA has shown that biofuel demand has led to the yearly destruction of a near Rhode Island-size swath of Amazon rain forest.

"I don't think people on the whole, the ones I've spoken to in government organizations, appreciate the huge loss of carbon dioxide sequestration potential you get from destroying forests," said Righelato.

Mac Post, a biofuel expert at the Oak Ridge National Laboratory, agreed. "If you're clearing high-content ecosystems to offset CO2 emissions, you're digging a hole. By what I can tell, it's a pretty deep hole, and you may not climb out," he said.

In the United States, the forests were cleared long ago. Here, the fuel-versus-forest question centers on pastures not being used to grow anything.

According to the Department of Energy's Billion Ton Vision (.pdf), which plots a course for supplying 30 percent of US transportation power with biofuel by 2030, the United States has 67.5 million acres of unused cropland. To meet those goals, 25 million acres -- an area the size of Kentucky -- would be dedicated to biofuel crops.

So far, no one is discussing converting those pastures into forests.

"We're more likely to see energy crops moving back into pastureland," said Robert Perlack, lead author of the Billion Ton Vision.

Ideally, Perlack said, both corn -- the most common and least energy-efficient of current biofuel crops -- and empty fields would give way to perennial plants, including fast-growing trees like willow and poplar. They have extensive root systems that keep some CO2 in the ground after harvesting.

In temperate climates, the trees could save as much carbon dioxide as planting new forests, write Righelato and Spracklen. But Righelato said the biofuel focus still distracts people from the real problem: how much fuel we use, and how carelessly we burn it.

Even with ostensibly environmentally-friendly Democrats taking political power in the US, this hasn't happened.

When proposing sweeping energy legislation earlier this month, the US House of Representatives dropped a requirement that automobiles get 35 miles per gallon of gasoline. The current average is 22, an efficiency lower than that of the original Model T Ford, and half of what China will require next year.


http://blog.wired.com/wiredscience/2007/08/cant-see-the-fo.html