CARB publishes study on E15 emissions

The California Air Resources Board published on July 15 the results of a multi-year study on the impact of E15 emissions. The study highlights the air quantity benefits that could be achieved by adopting the use of E15 in the state.

California does not currently allow the use of E15, as state regulations currently limit the ethanol content of gasoline to 10%. The CARB-initiated Multimedia Evaluation (MME) of E15 aims to understand any potential environmental or public health impacts of the use of E15 in California. California law generally requires that an MME be completed before adopting new motor vehicle fuel specifications.

As part of the MME for E15, CARB has contracted with the University of California at Riverside Bourns College of Engineering – Center for Environmental Research and Technology to assess exhaust emissions from the use of gasoline reformulated from California (CaFRG) containing 15% ethanol.

The study, supported by the Renewable Fuels Association, Growth Energy, the National Corn Growers Association and the US Council for Automotive Research, examined the impact of increasing ethanol content on vehicle exhaust emissions. 20 vehicles. All vehicles used in the study were model year 2016 or newer and equipped with three-way catalysts (TWc). Emissions measured include nitrogen oxides (NOX), total hydrocarbons (THC), non-methane hydrocarbons (NMHC), carbon monoxide (CO), carbon dioxide (CO2), particle mass, particle number, 1,3-butadiene, benzene, toluene, ethylbenzene, xylene isomers, ethanol and carbonyl compounds.

The study found that E15, compared to E10, achieved statistically significant PM reductions of 16-54% across the 20-vehicle fleet. Partial solid number emissions were 12% lower for E15. Total hydrocarbon missions have also been reduced by 5-6% for E15. For non-methane hydrocarbon emissions, E15 provided a 7-15% reduction compared to E10. E15 also resulted in a 12-27% reduction in carbon monoxide emissions. Weighted carbon dioxide emissions were 17% lower across the entire fleet of 20 vehicles. The study also indicates that E15 only resulted in a 1% reduction in fuel economy.

The release of the new study represents a significant step forward in California’s process to enable adoption of E15. The process, however, will take at least another year, possibly longer, to complete.

According to CARB, the MME is currently in its third year. The agency estimates that the development process should take at least another full year. After this period, CARB would be in a position to formally publish a proposed regulatory change, after which the Multimedia Working Group (MMWG) would make a recommendation to the Environmental Policy Council on whether potential regulatory changes to allow the use of E15 in California would have significant impacts. on public health or the environment. If the EPC determines that the adoption of E15 would not have a significant impact on public health or the environment, CARB would then be able to consider the adoption of regulatory amendments to authorize the use of the E15.

The RFA said the study represents a big step towards California’s approval of E15. “The results of this study clearly demonstrate that E15 reduces emissions of the harmful pollutants from tailpipes that contribute to air pollution and cause respiratory illnesses and other serious health issues,” Geoff said. Cooper, President and CEO of FRG. “In addition to reducing smog potential, E15 also reduces greenhouse gas emissions, displaces petroleum, lowers consumer pump prices, and supports renewable energy jobs in California and throughout the country. The benefits of E15 for the Golden State are compelling and clear, and we encourage CARB and the Environmental Policy Council to move quickly to approve the fuel. Now more than ever, California consumers want and need need the ability to choose lower-cost, low-carbon E15 at the pump.”

Growth Energy also welcomes the publication of the study. “The CARB report adds to the vast wealth of public, private and university research illustrating the vital role that high-ethanol blends play in protecting our air, our climate and our health,” said Emily Skor, CEO of Growth Energy. “No other solution offers the same immediate benefits in the fight against particulates, carbon monoxide and smog-forming pollutants linked to cancer, as well as neurological, cardiovascular and reproductive damage. Drivers nationwide are looking for better options at the pump, and E15 delivers. the savings they need and the clean air they deserve. California has long been a leader in clean energy, but it has lagged behind most other states when it comes to expanding access to E15 fuel blends. Today’s report should provide all the motivation CARB needs to accelerate the adoption of biofuels and accelerate progress toward the state’s clean energy goals.

Further information is available on the CARB website.

Denise W. Whigham