Almost all biofuels used today cause more greenhouse gas emissions than
conventional fuels if the pollution caused by producing these "green"
fuels is taken into account, two studies published Thursday have
The benefits of biofuels have come under increasing attack in recent
months as scientists have evaluated the global environmental cost of
their production. The new studies, published by the journal Science, are likely to add to the controversy.
These studies for the first time 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. The destruction of
natural ecosystems – whether rain forest in the tropics or grasslands
in South America – increases the release of greenhouse gases into the
atmosphere because the ecosystems are the planet’s natural sponge for
"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 on the environment and economics at Princeton
University. "Previously, there’s been an accounting error: Land use
change has been left out of prior analysis."
Plant-based fuels were originally billed as better than fossil fuels
because the carbon released when they are burned is balanced by the
carbon absorbed when the plants grow. But even that equation proved
overly simplistic because the process of turning plants into fuel
causes it own emissions – through refining and transport, for example.
The land-use issue makes the balance sheet far more problematic: The
clearance of grassland releases 93 times the amount of greenhouse gas
that would be saved by the fuel made annually on that land, said Joseph
Fargione, the lead author of the other study and a scientist at the Nature Conservancy.
"So for the next 93 years, you’re making climate change worse, just at
the time when we need to be bringing down carbon emissions."
The United Nations Intergovernmental Panel on Climate Change has
said that the world has to reverse the increase of greenhouse gas
emissions by 2020 to avert disastrous environmental consequences.
Together, the two studies offer sweeping conclusions: It doesn’t
matter if it is rain forest or scrub land that is cleared, although the
former releases more emissions than the latter. Taken globally, the
production of almost all biofuels resulted in such clearing, directly
or indirectly, intentionally or not.
The European Union and a number of national governments have
recently tried to address the land-use issue with proposals for
regulations stipulating that imported biofuels cannot come from land
that was previously rain forest, for example.
But even with such restrictions, Searchinger’s study said, the
purchase of biofuels in Europe and the United States leads indirectly
to the destruction of natural habitats. If vegetable oil prices go up
globally, as they have because of increased demand for biofuel crops,
new land is inevitably cleared as farmers in developing countries
switch production. Crops from old plantations and fields go to Europe
for biofuels, but new fields and plantations are created to feed people
Fargione said that the dedication of so much cropland in the United
States to growing corn for bioethanol had caused indirect land-use
changes far away. Previously, U.S. farmers rotated corn with soybeans
in their fields, alternating years. Now many grow only corn, meaning
that soybeans must be grown elsewhere. That elsewhere, Fargione said,
is increasingly Brazil, on land that was previously forest or savanna.
"Brazilian farmers are planting more of the world’s soybeans – and
they’re deforesting the Amazon to do it," he said.
International environmental groups and the United Nations responded
cautiously to the studies, saying that biofuels could still be useful.
"We don’t want a total public backlash that would prevent us from
getting the potential benefits," said Nicholas Nuttall, spokesman for
the UN Environment Program.
"There was an unfortunate effort to dress up biofuels as the silver
bullet of climate change," he said. "We fully believe that if biofuels
are to be part of the solution rather than part of the problem, there
urgently needs to be better sustainability criterion." He added that
the United Nations had recently created a panel to study the evidence.
The EU has mandated that countries use 5.75 percent biofuel for
transport by the end of 2008. In the United States, a proposed energy
package would require that 15 percent of all transport fuels be made
from biofuel by 2022. To reach these goals, biofuels production is
heavily subsidized at many levels on both continents. On Thursday,
Syngenta, a major global agricultural conglomerate in Switzerland that
is involved in biofuel crops reported that its annual profit rose by 75
percent in the past year.
Bob Dineen, president of the Renewable Fuels Association in
Washington, said the studies had "failed to put the issue in context."
"While it is important to analyze the climate-change consequences of
differing energy strategies, we must all remember where we are today,
how world demand for liquid fuels is growing, and what the realistic
alternatives are to meet those growing demands," he said. "Biofuels
like ethanol are the only tool readily available that can begin to
address the challenges of energy security and environmental protection."
Most of the biofuel sold in Europe is biodiesel made from vegetable
oils. Most of the biofuel in the United States is ethanol made from
corn. "EU decision makers cannot ignore that the EU fuel market" is
experiencing "an enduring diesel deficit – the EU is more and more
dependent on Russia for conventional diesel imports," the European
Biodiesel Board, a major industry group, said. The group has pushed for
a sustainability certification program for biofuels, as well as
criteria for assessing the greenhouse gas performance of such fuels,
with input from industry.
But the new studies suggested that when land use is taken into account few, if any biofuels, will be acceptable.
"This land-use problem is not just a secondary effect," Searchinger
said. "It is major. The comparison with fossil fuels is going to be
adverse for virtually all biofuels on cropland."
The only possible exception he could see for now, he said, was sugar
cane grown in Brazil, which takes relatively little energy to grow and
is readily refined into fuel. He added that governments should quickly
turn their attention to developing biofuels that did not require
raising crops, such as those made from agricultural waste products.
The land-use debate started in the Netherlands in 2006, when
researchers from Wetlands International and elsewhere found that
imported palm oil used to generate "clean" electricity was often grown
on palm plantations in Southeast Asia created from cleared peat land.
The Dutch government has since canceled the palm oil subsidy and banned
imports of the fuel, while hoping to develop better criteria to support
sustainable biofuels. Even Wetlands does not support a total ban on
biofuels, noting that some may be helpful.
Alex Kaat, a spokesman for the group, said: "If the whole point of
biofuels directives was to reduce greenhouse gas emissions, we’ve found
out that most biofuels are not really better than conventional fuels at
Via der Spiegel