Cellulosic Biofuels Win for Ground Transportation

by Lauren Quinn (University of Illinois Agri-View) Despite the fervor around electric vehicles and their potential to reduce the transportation sector’s carbon footprint, 2023 projections suggest electric vehicles won’t edge out gas-powered vehicles for decades to come. With conventional vehicles likely to dominate the ground fleet for the foreseeable future, University of Illinois Urbana-Champaign experts say cellulosic biofuels shouldn’t be discounted.

Researchers in the College of Agricultural, Consumer and Environmental Sciences and the Institute for Sustainability, Energy, and Environment at University of Illinois note that support for cellulosics has waned in part due to uncertainty around land availability, feedstock yields, costs and greenhouse gas emission savings. In a recent study, they quantified those uncertainties for multiple feedstocks and policy scenarios, concluding that cellulosic feedstocks outperform corn ethanol in nearly all cases — but will require considerable policy support to grow and sustain the industry.

“There are a lot of advantages for perennial feedstocks to decarbonize transportation,” said Madhu Khanna, College of Agricultural, Consumer and Environmental Sciences Distinguished Professor in Environmental Economics in the Department of Agricultural and Consumer Economics, the Alvin H. Baum Family Fund Chair, and director of Institute for Sustainability, Energy, and Environment, and a senior author on the U.S. Department of Energy-funded study led by the Center for Advanced Bioenergy and Bioproducts Innovation. “We need long-term policy commitments with assured demand for cellulosic biofuels, as well as short-term policy support like tax credits, which could be based on the carbon intensity of biofuels.”

The Center for Advanced Bioenergy and Bioproducts Innovation team developed a complex model integrating economics, crop growth information, land availability, refinery processes and carbon benefits to compare multiple biofuel feedstocks — corn, soybeans, corn stover, miscanthus, switchgrass and energy sorghum. The team projected outcomes for 2016 to 2030 under various policy scenarios. Those included a “no policy” or baseline scenario in which corn ethanol held steady at six billion gallons per year; a corn ethanol mandate of 15 billion gallons; and a corn + cellulosic ethanol mandate adding 16 billion gallons of cellulosic ethanol -- a total of 31 billion gallons -- by 2030.

The model predicted everything from the effect of ethanol mandates on corn and feedstock prices to where each feedstock would be grown most productively, taking into account land use change, greenhouse gas emissions and societal costs. In the end, the cellulosic mandate came out on top.

The model predicted that although cellulosic ethanol far exceeds the cost of corn ethanol, overall welfare costs of reducing greenhouse gas emissions would decrease with a cellulosic mandate thanks to additional carbon savings.

The study suggests policy support for cellulosics would not only be good for the planet, but also it could be good for society.

“Even if we achieve current policy targets for a 50% share of electric vehicles in new sales, it will take decades for the share of electric vehicles in the total stock to dominate due to slow turnover, particularly at a global level. A large share of the cars are still going to need liquid fuel. It's better driving them on low-carbon biofuels rather than on gasoline,” Khanna said. “It doesn’t have to be electric vehicles or biofuels. We have to have a balanced approach and rely on multiple paths to reducing emissions from the transportation sector.”

The study, “Quantifying uncertainties in greenhouse gas savings and abatement costs with cellulosic biofuels,” is published in the European Review of Agricultural Economics. The research was supported by the U.S. Department of Energy. READ MORE