UAI: Ethanol’s carbon impact in the fuel tank

By Urban Air Initiative | February 04, 2021

A new study is underway to determine whether corn-based ethanol makes a larger contribution to the reduction of GHG emissions than it is currently receiving credit. The Urban Air Initiative commissioned a study with Transport Energy Strategies to look at the impact ethanol has on carbon reduction in the gasoline itself.

Current modeling regarding ethanol and GHG emissions by DOE’s GREET model focus on how ethanol is produced, how it gets from the field to the tank. However, UAI contends that no one has considered the GHG impact of ethanol from the fuel tank to the tailpipe. This is where UAI proposes corn ethanol warrants additional credit for reducing GHG emissions.

When the gasoline market moved to E10, it reduced the need for toxic aromatics, the most carbon intensive components of fuel by eight billion gallons a year. Refiners reduce the carbon content of the fuel by putting fewer aromatics in its blendstock, in anticipation for ethanol to boost octane. No current DOE, CARB or EPA models take into account the carbon reduction in the actual U.S. gasoline supply because of ethanol. This new study will do just that.

There is no question that carbon reduction is the focus for the future of transportation. It is UAI’s point of view that this third-party research is needed to ensure ethanol receives the full benefit of the carbon reduction it provides. Third party confirmation that ethanol blends have a larger impact in reducing carbon emissions for the millions of cars on the road today will be valuable in discussions about creating a lower carbon liquid transportation fuel. The results of the study are expected in early this summer.