My research shows that the Renewable Fuel Standard, or RFS, has been harmful to the environment from its inception. Now, ten years after the 2005 Energy Policy Act, the program has resulted in higher CO2 emissions than would have occurred otherwise. It also harms the environment in other ways. Sadly, the adverse impacts of the RFS have grown worse since it was expanded by Energy Independence and Security Act (EISA) of 2007.
The notion that renewable fuels readily reduce CO2 is based on a scientifically incorrect understanding of carbon neutrality. Only under certain conditions does substituting a biofuel for a fossil fuel neutralize the CO2 leaving the tailpipe. For that to occur, harvesting the feedstock must significantly increase how rapidly cropland absorbs CO2 from the atmosphere on a net basis. That condition is not met for the corn ethanol mandated by the RFS. It might be satisfied for cellulosic feedstocks, but once properly evaluated, the gains may not be as great as advocates assume.
The lifecycle models used to calculate fuel carbon footprints, including EPA's RFS model and the DOE-sponsored GREET model, automatically credit all biofuels with complete carbon neutrality without checking whether that assumption is valid. My studies, which rely on crop data instead of computer modeling, find that the carbon neutrality condition is not met. We evaluated corn ethanol for which lifecycle analysis claimed a 40% reduction in greenhouse gas emissions compared to gasoline. But examining data for the cropland serving the facility found no significant reduction in emissions. Under some circumstances, the emissions could be as much as 70% higher than those of gasoline. These results do not even include indirect land-use change, which would increase biofuel-related emissions even more.
The key problem is that diverting harvest from existing productive land does not remove more carbon from the air than was already being removed during prior crop growth; all it does is shuffle carbon around. In effect, it robs Peter to pay Paul.
Our ongoing research involves a detailed carbon balance analysis of U.S. renewable fuel production since 2005. Preliminary results show that no significant direct CO2 reduction can be claimed for the RFS. Once indirect land-use change is considered, the result is substantially higher CO2 emissions overall.
Excess CO2 is not the only environmental harm caused by the RFS. Fellow University of Michigan researchers have documented how ethanol production has destroyed habitat for waterfowl and other wildlife. Expanding corn production is worsening water pollution, contributing to algae blooms in the Gulf of Mexico and Lake Erie. And as for air pollution, recent research found that the country’s third largest corn ethanol refinery emits 30 times more pollution than assumed for the RFS regulatory analysis. Ethanol's corrosive properties are also incompatible with many cars already on the road and degrade the operation of lawn mowers, motor boats and other gasoline-powered equipment used by homeowners and businesses alike.
In summary, a careful look at the data reveals that the studies used to justify the RFS were flawed. Scientifically speaking, lifecycle analysis is an inappropriate method for specifying public policy. Inserting lifecycle requirements into the law has proven to be a mistake. Only direct, year-at-a-time accounting provides a sound way to evaluate the CO2 impact of fuels. Once that is done, it is clear that the production and use of biofuels as mandated by the RFS has increased CO2 emissions to date.
Note: Links have been added here to references for key statements; for the full written testimony, see:
Here are links to a video of the hearing and to a follow-up interview on E&E TV.