Ethanol Mandates Are Outdated, Says Environmental Group
Do Advanced Biofuels Have Lower Life-Cycle Carbon Density than Gasoline?
An environmental group contends advanced biofuels made from switchgrass and leftover corn stalks are greener than first-generation alternatives made from corn. An analysis by the Environmental Working Group (EWG) draws on evaluations of gasoline carbon intensity that support calls to overhaul federal biofuel mandates.
Now, some oil industry organizations and other groups have seized on these studies that question the environmental benefits of traditional corn-based ethanol. Meanwhile Corn Belt lawmakers who support the present mandates argue some of the next-generation biofuels now in production threaten the corn growers’ business model. But the working group claims the current mandate is crowding out next generation biofuels.
The EWG is calling on Congress to consider a broader array of environmental effects from various biofuels to be factored into the renewable fuel standard. The mandate should consider the impacts of biofuels production and use on air, water and soil quality, as well as greenhouse gas emissions.
“It’s time to break up the corn ethanol monopoly to make room for next-generation biofuels that could reduce carbon emissions,” said Emily Cassidy, of the EWG.
The study evaluated gasoline, traditional corn-based ethanol and alternatives made with switchgrass or corn stover. Two scientists assessed the carbon dioxide emissions from those fuels over their entire life cycle while factoring the initial production and combustion of the fuel and the land-use changes and other factors that go into the feedstocks used to create it.
In particular, ethanol made from Texas switchgrass was found to have a life-cycle carbon intensity 47 percent lower than gasoline. Growing switchgrass also provides other environmental benefits, including the fact that it can be grown on land unsuitable for food while reducing fertilizer pollution in waterways and slowing soil losses.
In the final analysis, the life-cycle carbon intensity of renewable fuels is an important consideration in the federal emissions mandates. Currently corn-based ethanol is required to produce 20 percent fewer greenhouse gases than gasoline, but the broad- based support of next generation biofuels may lead to a revision of this mandate and a political fight on Capitol Hill.