Today, University of Michigan Energy Institute researchers, led by longtime biofuels critic Professor John DeCicco, released a study funded by the American Petroleum Institute (API) claiming biofuels do not reduce carbon emissions compared to petroleum. Below is a statement from Renewable Fuels Association President and CEO Bob Dinneen:
This is the same study, same flawed methodology, and same fallacious result that Professor DeCicco has churned out multiple times in the past. He has been making these arguments for years, and for years they have been rejected by climate scientists, regulatory bodies and governments around the world, and reputable lifecycle analysis experts.
As crazy as it sounds, Prof. DeCicco is essentially suggesting that plants ultimately used for bioenergy don't absorb carbon dioxide from the atmosphere as they grow. In other words, he and his sponsors at the API are arguing that the scientific community's centuries-old understanding of photosynthesis and plant biology is wrong. DeCicco's assertion that plants somehow emit more carbon when burned as fuel than they take in from the atmosphere during photosynthesis defies the most basic laws of plant physiology.
Just like Prof. DeCicco's last study, this work was funded by the API, which obviously has a vested interest in obscuring and confusing accepted bioenergy carbon accounting practices. It's a bit like the tobacco industry funding a study that says bubble gum is worse for the human body than cigarettes. While it's flattering that API has taken such an interest in the climate benefits of biofuels, the public would be better served if the oil industry spent its time and money examining and owning up to the very real and very negative climate impacts of petroleum.
The truth is, biomass crops used to produce energy act as temporary carbon sinks. During growth, they quickly absorb CO2 that was just in the atmosphere. The same amount of CO2 is then returned to the atmosphere when the carbon in the crop is combusted for energy. In this way, the use of biomass for energy recycles atmospheric carbon as part of a relatively rapid cycle. In contrast, the use of fossil fuels adds to atmospheric CO2 by emitting carbon that was previously sequestered deep underground for millions of years.
According to researchers at Duke University, the University of Minnesota, and Oak Ridge National Laboratory: A critical temporal distinction exists when comparing ethanol and gasoline lifecycles. Oil deposits were established millions of years in the past. The use of oil transfers into today's atmosphere GHGs that had been sequestered and secured for millennia and would have remained out of Earth's atmosphere if not for human intervention. While the production and use of bioenergy also releases GHGs, there is an intrinsic difference between the two fuels, for GHG emissions associated with biofuels occur at temporal scales that would occur naturally, with or without human intervention. Hence, a bioenergy cycle can be managed while maintaining atmospheric conditions similar to those that allowed humans to evolve and thrive on Earth. In contrast, the massive release of fossil fuel carbon alters this balance, and the resulting changes to atmospheric concentrations of GHGs will impact Earth's climate for eons.
For more information, here is a more detailed statement from RFA, and here is a technical response sent March 2015 from a handful of other researchers to the previous DeCicco paper.