We appreciate the opportunity to provide comments ahead of California Air Resources Board’s response to Governor Newsom’s June 12, 2025, executive order regarding recommended additional actions to “spur light-, medium-, and heavy-duty zero emission vehicle (ZEV) adoption” in the state. Growth Energy is the leading voice in America’s biofuels industry, representing 97 U.S. plants that each year produce more than 9.5 billion gallons of renewable fuel; 131 businesses associated with the production process; and tens of thousands of biofuel supporters around the country. Together, we are working to bring better and more affordable choices at the fuel pump to consumers, improve air quality, and protect the environment for future generations. We remain committed to helping our country diversify our energy portfolio in order to grow more green energy jobs, decarbonize our nation’s energy mix, sustain family farms, and drive down the costs of transportation fuels for consumers.
As Governor Newsom’s executive order states, “California has worked closely with the auto industry and other stakeholders” to achieve “feasible, cost-effective” reduction of air pollution. Our industry believes in this goal as well. Bioethanol has played a crucial role in the reduction of emissions in the transportation sector, and we believe it will continue to contribute to emissions reductions for decades to come. According to the Transportation Energy Institute, bioethanol has led all biofuels to have been among the largest contributors to the success of California’s GHG reductions through the Low Carbon Fuel Standard (LCFS).
Finalizing E15 Multimedia Evaluation and Rulemaking
We appreciate the inclusion of funding to complete the analysis and rulemaking for the approval of E15, a fuel blend consisting of 10.5 to 15 percent bioethanol in the state’s current budget. It is a welcome and much-needed development in providing California drivers access to a more affordable, lower carbon fuel. We look forward to continuing to work with CARB to complete this process so that California drivers have access to the same more affordable fuel choices available to drivers at more than 4,300 retail locations in 34 states.
Consumers across the country have embraced E15’s reputation as a more environmentally beneficial, more affordable fuel. This rapid expansion of retailers offering E15 began in 2012, shortly after the EPA approved it, at which time there were zero retailers offering it. Since then, drivers in America have relied on E15 to drive 160 billion miles.
Fueling up with E15 would also save consumers 10-30 cents per gallon on average. In some locations in the United States, consumers saw more than $1 per gallon in savings.
Additionally, concerns about infrastructure compatibility and the cost of upgrading retail fueling equipment are unfounded. Where E15 is available for purchase, retailers have not encountered major impediments preventing them from offering E15. For example, all underground storage tanks (USTs) made of steel are approved for 100% bioethanol while all double-walled fiberglass USTs constructed since 1990 are similarly approved. With respect to dispensers, more than 90% of the US market share of gasoline dispensers is held by two dispenser manufacturers, both of which offer compatibility and a warranty for dispensers for blends of fuel with higher ethanol content than E10. Gilbarco dispensers installed since 2008 carry a warranty for 15% ethanol fuel. Wayne dispensers installed since 2017 are compatible for up to E25, ensuring E15 is easily within specifications for their dispensing equipment. Given the approximate average life of a dispenser, 10-15 years, the vast majority of dispensers installed before 2008 have either been or are about to be replaced.
Bioethanol’s Carbon Reduction Value
We have noted in previous comments in response to proposed amendments of both the LCFS and Advanced Clean Cars II (ACCII) that bioethanol is a primary solution for reducing carbon and air toxics emissions in the state’s liquid fuel supply. Data from Environmental Health and Engineering shows that bioethanol reduces greenhouse gas emissions by an average of 46 percent compared to gasoline and can provide even further GHG reductions with the utilization of readily available technologies. The board has previously recognized the contributions bioethanol can make to carbon reductions. In 2011, CARB reported the average carbon intensity (CI) for ethanol at 88 g/MJ. Through the end of 2022, the average recorded CI for bioethanol has decreased to 59.21 g/MJ, a 33 percent reduction in CI. Additional CI reductions are anticipated as projects of diverse technological variety at ethanol biorefineries come online starting this year.
Expanded use of higher bioethanol blends will allow the millions of internal combustion engine (ICE) vehicles remaining on the road beyond the implementation of the Board’s 2035 rule requiring all new vehicle sales be zero emission vehicles to continue contributing to the state’s GHG and emissions reduction goals. If CARB not only approved E15, but replaced E10 with E15, this switch would be
responsible for the GHG-reduction equivalent of removing more than 400,000 ICE vehicles from California’s roads without negatively impacting California drivers.
Bioethanol’s other environmental benefits are also noteworthy. As has been researched by the University of California, Riverside and the University of Illinois at Chicago, the use of more bioethanol and bioethanol-blended fuel reduces harmful particulates and air toxics such as carbon monoxide, benzene, and other harmful particulates. The benefits of ethanol in reducing particulate matter (PM) were recently confirmed by the U.S. Environmental Protection Agency’s (EPA) work with Environment and Climate Change Canada. That study demonstrated that fuel with increased ethanol content showed the deepest reduction in PM compared to the baseline fuel with heavy aromatics.
E85, Flex-Fuel Vehicles, and CCUS
Additionally, California’s existing approval of E85 has resulted in significant growth of it being used in flex-fuel vehicles (FFVs): more than 118 million gallons have been sold at 375 locations across the state in 2023 alone. Additionally, the current size of California’s FFV fleet stands at more than 1.14 million vehicles. Despite the size of California’s FFV fleet flattening, E85 usage continues to grow. There is a clear appetite and market for this environmentally beneficial fuel. The use of E85 will promote even greater reductions in GHG emissions and reductions of air toxics. We would continue to encourage CARB to implement policies that strongly incentivize and as necessary, require the production and use of flex-fuel vehicles, as well as continued investment in infrastructure for expanded access to E85 in the state. In doing so, the Board will be achieving multiple goals: improving air quality and GHG emissions, reducing the state’s
dependence on fossil fuels, and providing consumers with an affordable choice to power their vehicles.
In August 2023, CARB updated the California Transportation Supply (CATS) Model to recognize the value of carbon capture utilization and sequestration (CCUS) during the bioethanol production process. By accounting for CCUS, a process incentivized by the Inflation Reduction Act, the pathway CI for E85— approved for use in California—was updated such that it reduces the assumed CI score for bioethanol from 66 gCO2e/MJ to 35 gCO2e/MJ. We appreciate CARB’s recognition of the bioethanol industry’s efforts to further reduce carbon emissions via CCUS. This is a welcome update to CATS and a recognition of the positive impact bioethanol has on California’s emissions reduction goals.
We encourage CARB to consider the value of fuel blends such as E85 in reducing light-duty vehicle emissions and how it can complement the state’s GHG emissions reductions policies.
High Octane/Midlevel Bioethanol Blends
As CARB considers the future fleet, it is important to consider the benefits of using higher octane fuels such as bioethanol in conjunction with more efficient engines. Growth Energy has been an industry leader in advocacy in this area, first commenting to both CARB and EPA about the need for higher octane, midlevel bioethanol blends when the GHG standards for vehicles were being first developed in 2012. At that time, we submitted a proposal for a 100 Research Octane Number (RON), E30 (30 percent bioethanol) fuel blend for both vehicle certification and for consumer use. The science supporting the benefits of a high-octane fuel — specifically a midlevel ethanol blend in the E20 to E30 range in conjunction with a high compression ratio engine – is not new and has been well explored by several national laboratories including Oak Ridge National Laboratory, National Renewable Energy Laboratory, and Argonne National Laboratory as well as automobile manufacturers and other scientific institutions. Bioethanol has a very high-octane number relative to other gasoline hydrocarbons, has a lower carbon content than the gasoline components it generally replaces, and has many other benefits that assist in combustion to increase engine efficiency and reduce both tailpipe GHG and criteria pollutant emissions.
To briefly summarize, multiple studies have shown that a high RON, midlevel bioethanol blend (e.g., 96-RON E20 or 100-RON E30) when paired with various higher compression ratio engines yield tailpipe CO2 emissions reductions of at least 5 percent, which in most instances were also coupled with efficiency gains. Some studies also showed significant volumetric miles per gallon savings associated with the higher efficiency engines and a high-octane fuel. One study that was submitted to EPA in response to their Draft Technical Assessment Report (TAR) by Air Improvement Resources, “Evaluation of Costs of EPA’s 2022-2025 GHG Standards with High Octane Fuels and Optimized High Efficiency Engines,” showed that the use of a 98 RON, E25 would reduce the cost of a MY 2025 vehicle by $400 and a popular crossover SUV by as much as $873. Not only are the benefits of midlevel bioethanol blends well understood by the scientific community, but the automobile industry has for years acknowledged the importance of affordable, high-octane fuels coupled with high-compression ratio engines as important to attaining regulatory compliance and improving vehicle performance in the most economical manner possible.
When you examine the data, there are clear benefits of moving to a high-octane, midlevel bioethanol blend, such as E30, including vehicle engine efficiency, lower tailpipe emissions, and increased use of renewable fuel. We believe that the use of midlevel bioethanol blends will continue to drive investment in more efficient vehicles, as well as lower carbon biofuels.
Bioethanol/Fuel Cell Technology
Direct bioethanol fuel cells for use in motor vehicle transportation have been in development by Nissan for some time. As recently as January of 2020, Nissan and Lawrence Berkeley National Laboratory have published research on the use of 100 percent bioethanol in fuel cell technologies and innovations. This technology not only meets zero emission vehicle requirements but further eliminates particulates from tailpipe emissions. Using bioethanol in conjunction with a fuel cell would require less infrastructure change and investment and would help the state meet its ambitious goals for climate and vehicle. As CARB considers changes to policies on zero emission vehicles in conjunction with the LCFS, we would strongly encourage CARB to consider ways to further develop this technology.
Thank you for the opportunity to provide comments on ZEV adoption in the state. We urge the Board to recognize the role biofuels has played and can continue to play in making California’s fuel mix more sustainable, and help the state achieve its progressive climate goals through the expanded use of bioethanol.