Some Biofuels Are Worse Environmentally
Than Fossil Fuels, Analysis Shows
Jan 7, 2008 - ScienceDaily
|
US cornfield. Fuels made from
U.S. corn, Brazilian soy and Malaysian palm oil
may be environmentally worse overall than fossil
fuels. (Credit: Bob Nichols) |
Biofuels reduce greenhouse-gas emissions
in comparison to fossil fuels. Smithsonian researchers
highlight a new study that factors in environmental
costs of biofuel production. Corn, soy and sugarcane
come up short. The authors urge governments to be
far more selective about which biofuels they support,
as not all are more environmentally friendly than
fossil fuels.
Because fossil fuels contribute to global
warming and supplies are dwindling, more eco-friendly
alternatives are required. However, biofuels may not
be superior if their production results in environmental
destruction, pollution and damage to human health,
argue postdoctoral fellow Jörn Scharlemann and William
Laurance, staff scientist at the Smithsonian Tropical
Research Institute.
A new study by Zah et al., commissioned
by the Swiss government, calculates the relative merits
of 26 biofuels based on relative reduction of greenhouse-gas
emissions and an environmental-impact index, which
includes damages to human health and ecosystems and
natural resource depletion.
The Swiss study identifies striking
differences in the environmental costs of different
biofuels. Fuels made from U.S. corn, Brazilian soy
and Malaysian palm oil may be worse overall than fossil
fuels. The best alternatives include biofuels from
residual products, such as recycled cooking oil and
ethanol from grass or wood.
The Zah et al. study falls short in
that it fails to consider secondary consequences of
biofuels, such as rising food costs, but it is a big
step forward in providing a way to compare the environmental
benefits and costs of dozens of different biofuels.
"Different biofuels vary enormously
in how eco-friendly they are," said Laurance. "We
need to be smart and promote the right biofuels, or
we won't be helping the environment much at all."
Journal article: Scharlemann, JPW and
Laurance, WF (2008); "How Green are Biofuels?" Science
319: 52-53
Adapted from materials provided by Smithsonian
Tropical Research Institute, via EurekAlert!, a service
of AAAS.
|