Yes, we've done shows suggesting the same. But, and it is a big but, most biofuels are now made from non-food based crops that actually complement farmers growing seasons. These plants also provide much needed ground cover when fields are normally barren.
Therefore, we feel biofuels are, in fact, much more friendly to the environment.
Are biofuels worse for the planet than gasoline? A new study suggests that biofuels can mitigate only 37 percent of the CO2 released by burning the biofuel.
Corn ethanol and biodiesel biofuels may be more environmentally damaging than petroleum gasoline, according to a new study from the University of Michigan Energy Institute (UMEI),
The surprising finding comes after the research team, led by UMEI researcher John DeCicco, analyzed the amount of carbon dioxide (CO2) absorbed as the crops grow and then released when they are burned as biofuel. They calculated that the aggregate US crop yield can remove only 37 percent of the CO2 that burning biofuel releases into the air.
The surprising finding comes after the research team, led by UMEI researcher John DeCicco, analyzed the amount of carbon dioxide (CO2) absorbed as the crops grow and then released when they are burned as biofuel. They calculated that the aggregate US crop yield can remove only 37 percent of the CO2 that burning biofuel releases into the air.
“What
we found is that when you actually look at how quickly crops like corn
and soybeans pull CO2 from the air and compare that with the emissions
that occur when the biofuels like ethanol and biodiesel are burned, you
find out that they are not carbon neutral like everyone has been
assuming,” Dr. DeCicco tells The Christian Science Monitor.
That's a flawed premise, argues Daniel Schrag, a
geology professor at Harvard who advises the EPA on bioenergy climate
impacts. He says that biofuels don't have to be carbon neutral to be an
environmentally preferable alternative to petroleum gasoline.
“For about 10 years there have
been very careful studies of corn ethanol and all of the fossil carbon
that is used to make it ... and those studies have gotten a range of
answers, but it is about a 20 percent reduction of net emissions
relative to gasoline,” says Professor Schrag in an interview with the
Monitor. “Nobody ever thought corn ethanol was carbon neutral, because
there are lots and lots of fossil inputs to it.”
The
biofuel debate has raged for years, with critics worried about the
impact of the additional land deforested to convert to corn fields, and
proponents arguing for biofuel as a green alternative to gasoline.
Another group says that it is really too soon to tell.
The
conversation has generally been dictated by the food vs. fuel debate.
This focuses on the indirect consequences of biofuel crop production,
such as land use and deforestation, which create a ripple effect felt by
the entire global food market.
DeCiccio decided to
question the basic life cycle analysis model that previous studies
relied on, some of which had assumed that biofuel is carbon neutral and
that only production-related greenhouse gas emissions need to be taken
into account when comparing biofuel to fossil fuels.
Whether
you burn biofuel ethanol or petroleum gasoline, he argues, the same
amount of CO2 is released into the atmosphere. So comparing the fuels'
environmental impacts comes down to how efficiently that carbon can be
removed from the air, he says – and forests are better at that than
cornfields.
"The United States uses 40 percent of its
corn harvest to make ethanol, but that does not mean mean we eat 40
percent less corn-based products," DeCiccio tells the Monitor.
DeCiccio
explains that as cropland once used for food is transferred to fuel
use, food must be produced elsewhere, meaning that more grasslands and
forests are converted to production. However, grasslands and forests can
neutralize more carbon dioxide than crops, he says.
Schrag says that this ignores the long-term perspective, when biofuels make up for carbon loss from forests.
“In
their approach time scale does not come into it,” he tells the Monitor.
“They are looking at crop yield data and assuming that you should
balance the carbon cycle based on how much crops you produce.”
Michael
Wang, a researcher at the Argonne National Laboratory, tells the
Monitor that he also questions the study's carbon accounting, arguing
that the study does not properly account for the carbon uptake or that
corn production for both ethanol and for food increased over the period
of the study.
“The carbon uptake by the US farming
systems is calculated based only on grain harvest," Dr. Wang tells the
Monitor. "Carbon uptake embedded in above- and below-ground biomass is
ignored in the paper with a simple assumption that carbon in these
biomass sources are oxidized back to the air."
Additionally,
the research received funding from the American Petroleum Institute,
which critics say is grounds for skepticism, but the UMEI researchers
stated that “the analysis, results and conclusions presented [in their
study] are those of the authors alone.”
Other experts
have come out in support of the research. Tim Searchinger, a researcher
at the Science, Technology, and Environmental Policy Program at
Princeton University, said that the research was very narrow, but
useful.
“This article is saying that if you think the
reason biofuels are helping to solve climate change is because the US is
increasing its production of crops and that increased production of
crops offsets the carbon release from burning the biofuels, you’re
wrong. That is not what is happening,” Mr. Searchinger tells the
Monitor. “What reduces carbon in the atmosphere is not the biofuel, it
is the plant growth.”
DeCicco says that the solution is not to make biofuel more efficient, but to invest in reforestation.
“We
should not be trying to make biofuels at all, any time soon,” DeCicco
tells the Monitor. “It is much better to reforest and restore
ecosystems.... Reforestation is a much better way to remove CO2 than
anything we can do with biofuels.”
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