Journal reference: Science
(DOI:10.1126/science.1141361)
Biofuels Switch a Mistake, Say Researchers
By Tristan Farrow
The Guardian UK
Friday 17 August 2007
Increasing production of biofuels to combat climate
change will
release between two and nine times more carbon gases over the next 30
years than fossil fuels, according to the first comprehensive analysis
of emissions from biofuels.
Biofuels - petrol and diesel extracted from plants -
are presented
as an environmentally friendly alternative to fossil fuels because the
crops absorb carbon dioxide from the atmosphere as they grow.
The study warns that forests must not be cleared to
make way for
biofuel crops. Clearing forests produces an immediate release of carbon
gases into the atmosphere, accompanied by a loss of habitats, wildlife
and livelihoods, the researchers said.
Britain is committed to substituting 10% of its
transport fuel with
biofuels under Europewide plans to slash carbon emissions by 2020.
"Biofuel policy is rushing ahead without
understanding the
implications," said Renton Righelato of the World Land Trust, a
conservation charity. "It is a mistake in climate change terms to use
biofuels."
Dr Righelato's study, with Dominick Spracklen from
the University
of Leeds, is the first to calculate the impact of biofuel carbon
emissions across the whole cycle of planting, extraction and conversion
into fuel. They report in the journal Science that between two and nine
times more carbon emissions are avoided by trapping carbon in trees and
forest soil than by replacing fossil fuels with biofuels.
Around 40% of Europe's agricultural land would be
needed to grow
biofuel crops to meet the 10% fossil fuel substitution target. That
demand on arable land cannot be met in the EU or the US, say the
scientists, so is likely to shift the burden on land in developing
countries.
The National Farmers Union said 20% of Britain's
agricultural land
could be used to grow biofuels by 2010. However, the researchers say
reforesting the land would be a better way to reduce emissions.
Biofuels look good in climate change terms from a
Western
perspective, said Dr Spracklen, but globally they actually lead to
higher carbon emissions. "Brazil, Paraguay, Indonesia among others have
huge deforestation programmes to supply the world biofuel market", he
said.
The researchers say the emphasis should be placed on
increasing the
efficiency of fossil fuel use and moving to carbon-free alternatives
such as renewable energy.