Dear Mr. Zeldin,
Growth Energy is the nation’s largest association of biofuel producers, representing 97
U.S. plants that each year produce more than 9.5 billion gallons of low-carbon, renewable fuel;
131 businesses associated with the production process; and tens of thousands of biofuel
supporters around the country. Our members are critical to the supply of biofuel in the United
States. Our industry is poised to assist the administration’s energy goals by providing low-cost,
innovative, and American-made fuel as we remain committed to helping our country diversify its
energy portfolio and provide consumers with better and more affordable choices at the fuel
pump.
Growth Energy appreciates the administration’s continuing support of the biofuels
industry and recognition of its vital role in ensuring American energy dominance. Renewable
liquid fuels, such as ethanol, help our country increase its energy security and improve the
environment, all while reducing consumer costs. Liquid fuels will continue to play a dominant
role in the transportation sector now and for decades to come, and EPA was right to recognize
that our nation should not put the thumb on the scale on – nor be solely dependent on – only one
vehicle technology.
U.S. ethanol from corn and sorghum is a readily available and affordable means to
broaden our domestic fuel supply while providing considerable benefits to consumers, our rural
economy, and our environment. Today, ethanol represents more than 10 percent of our nation’s
gasoline supply and is poised to do much more with blends such as E15, which is approved for
all 2001 and newer vehicles, as well as E85 in flex-fuel vehicles. Indeed, on average, E15
provides $0.10 – $0.15 savings to consumers relative to traditional regular unleaded gasoline.
Ethanol’s environmental benefits with respect to vehicle emissions, unrelated to GHGs,
are well-established. To begin with, ethanol boosts octane in fuel without the harmful impacts of
alternative octane-boosting fuel additives such as methyl tert-butyl ether (MTBE), lead, and
2
aromatics including benzene, toluene, ethylbenzene, and xylene (BTEX) or olefins. Indeed, the
level of aromatics in fuel decreases by about seven percent for every 10 percent by volume
increase in ethanol content.1 Decreasing aromatics in fuel has direct impacts on tailpipe
emissions, with higher-ethanol fuels resulting in lower emissions of black carbon (BC), particle
number (PN), BTEX, and olefins.2 Using higher blends of ethanol also reduces total hydrocarbon
(THC), carbon monoxide (CO), and particulate matter (PM) emissions. For PM emissions in
particular, recent studies have demonstrated substantial benefits from higher blends of ethanol in
fuel.3 Vehicles and fuels work as a system, and innovations in vehicle technology, coupled with
use of higher blends of biofuels like ethanol can go a long way to reducing the recognized, local
environmental harms associated with these pollutants.
With a stable regulatory landscape based on recognized science, and with access to
drivers without needless market barriers, the biofuels industry can deliver renewable, low-cost,
and high-performing fuel solutions that provide environmental and economic benefits now and
well into the future. To achieve these important benefits, we urge the EPA to provide strong and
clear policy direction to encourage the adoption of home-grown, renewable fuel blends,
including the following:
1. EPA should take action to remove barriers and encourage the use of blends such as
E15 and E85 in today’s vehicle fleet.
2. EPA should consider a higher octane fuel requirement. Higher octane fuels give
automakers greater flexibility in engine efficiency.
3. EPA should approve a high octane, midlevel ethanol fuel for vehicle certification
such as the 100 RON, E30 that Growth Energy first proposed and should also work
with Congress to consider solutions from the Next Generation Fuels Act to further the
use of high-octane fuels.
4. EPA and NHTSA should work together to re-establish appropriate credit to
automakers for the production of flex-fuel vehicles, such as through Section 202 of
the Clean Air Act, which could be used to provide credits to manufacturers who
create engines and technologies that facilitate the use of higher blends of ethanol and
other fuels.
5. EPA should work quickly to finalize its RFS proposal for 2026 and 2027, which
should include 100 percent reallocation of 2023-2025 small refinery exemptions
1 Kazemiparkouhi et al., Comprehensive US database and model for ethanol blend effects on regulated tailpipe
emissions. 812 Science of The Total Environment 151426, (Mar. 2022). 2
MacIntosh, et al., Response to Proposed Renewable Fuel Standard (RFS) Program Standards for 2023–2025,
Environmental Health & Engineering (Feb. 10, 2023).
3 See Karavalakis, Durbin, & Tang, Final Report, Comparison of Exhaust Emissions Between E10 CaRFG and
Splash Blended E15, Prepared for: California Air Resources Board (CARB), Growth Energy Inc./Renewable Fuels
Association (RFA), and USCAR (Jan. 2022).
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(SREs), as well as finalize its proposal to broaden use of existing fuel infrastructure
for E15.
6. Finally, we greatly appreciate EPA’s work to provide emergency RVP waivers for
E15 this summer, and we urge EPA to work with Congress on a permanent legislative
solution for the year-round sale of higher ethanol blends.
Thank you again for your staunch support of the biofuels industry and recognition of the role that
our producers and farmers play in providing demonstrated, affordable, and effective energy
solutions.
Sincerely,
Chris Bliley
Senior Vice President of Regulatory Affairs
Growth Energy
September 22, 2025
VIA REGULATIONS.GOV
Mr. Lee Zeldin, Administrator
U.S. Environmental Protection Agency
Office of the Administrator, Mail Code 1101A
1200 Pennsylvania Avenue, N.W.
Washington, D.C. 20460
RE: Reconsideration of 2009 Endangerment Finding and Greenhouse Gas Vehicle
Standards, Docket ID No. EPA-HQ-OAR-2025-0194