Debate about whether biofuels are environmentally friendly goes on — especially
around land use. At issue is whether the amount of land available for agricultural production can support the growing global population’s demand for both food and fuel.
As carbon-neutral policies around the country begin to take hold, there’s a
growing interest in the total environmental impact of alternative sources of
energy — also known as life cycle analysis (LCA).
The California Air Resources Board, Argonne National Laboratory and
other scientists have separately conducted LCAs of
and found that it reduces greenhouse gas emissions by 50 to 86 percent, compared
Still, debate about whether biodiesel, ethanol and other biofuels are
environmentally friendly goes on — especially around land use. At issue is
whether the current amount of land available for agricultural production can
support the growing global population’s demand for both food and fuel.
One of the biggest myths about biodiesel is that the renewable fuel increases
greenhouse gases because it causes land to be cleared. New cropland is not
needed to make biodiesel in the United States, because it is produced from
co-products and byproducts of crops already grown for food and other materials.
In fact, from 2008 to 2016, the US tripled biodiesel use and doubled exports of
whole soybeans to China, while farmland decreased by 18 million acres.
“In the US, we have lots of unused land available to farmers who can convert it
to corn or soybeans. There has been no need to cut forests here,” said Farzad
Taheripour, a research associate professor in agricultural economics at
Purdue University. “In addition, crop productivity has increased
significantly over time, providing more yield on the same amount of land.
Because of those, the expected deforestation or conversion of natural land has
not had to largely happen to account for US biofuel production.”
The current research about biodiesel weakens the criticism stemming from a
well-known 2008 study by scientists
at Princeton University published in Science magazine. They argued that
increased biofuel crop production will result in land-use changes — such as
— that end up releasing a great deal of carbon dioxide into the atmosphere. The
land-use changes thus undermine the benefits of cleaner-burning biofuels.
However, in response to the 2008 study, Argonne National Laboratory found that
the Princeton researchers did not properly consider increasing crop yields per
acre, which reduces the need to produce replacement food on other acreage.
Now, new research by Taheripour also should quell concerns about the effects of
US biofuels production on deforestation in other parts of world. His
showed that less 1 percent of the land cleared in Indonesia and Malaysia
can be tied to US biofuel production.
Taheripour and the late Wallace Tyner, who also contributed to this study,
have been modeling environmental impacts of energy policy for over a decade.
Together, with various collaborators and researchers, they developed the
for the California Air Resources Board to quantify the market-mediated impacts
of the California Low-Carbon Fuel Standard and the national Renewable Fuel
Those polices hold biofuels accountable for increased agricultural production
predicted to occur all around the world.
The National Biodiesel Foundation supported a portion of Purdue’s research.
Significant funding also came from the Federal Aviation Administration —
which is working with
to identify fuels that have total carbon benefits, including indirect impacts on
global forests and land use change.