RFS ethanol mandate drives up fuel costs, study says

The Renewable Fuel Standard has become a case study in policy overload, with R Street saying the mandate has pushed fuel costs higher, delivered uncertain climate gains and saddled taxpayers with spillover costs in water quality and enforcement. EPA still describes the program, created by the Energy Policy Act of 2005 and expanded by the Energy Independence and Security Act of 2007, as a tool to cut greenhouse gases, grow renewable fuels and reduce reliance on imported oil, but the implementation stack now includes annual volume standards, RINs, small refinery exemptions, cellulosic waiver credits and waiver petitions.

R Street’s two-part analysis said its modeling puts the RFS at more than $1,400 per ton of carbon dioxide reduced, even under generous assumptions about emissions abatement. The group said the mandate also encouraged corn overproduction that has worsened fertilizer runoff and helped fuel harmful algal blooms in the Great Lakes and the Gulf of Mexico, costs that communities have had to absorb through water treatment, remediation and lost tourism.

The mismatch between statute and market showed up early. EPA finalized the first RFS rule in 2007, after setting a default standard that required 2.78% of gasoline sold or dispensed in 2006 to be renewable fuel. R Street said Congress and regulators assumed gasoline demand would keep growing about 1% a year, but the 2008 recession drove U.S. gasoline demand down 6% between 2007 and 2012. That left the program trying to force higher ethanol use into a fuel pool that was not expanding as expected.

A second assumption also failed: lawmakers expected cellulosic ethanol to be commercially commonplace by around 2015, but that market never materialized. EPA has since had to manage a series of workarounds and exemptions that underscore the policy’s operational strain, rather than a clean compliance path for refiners and fuel blenders.

The fight is not confined to the core mandate. In May 2026, the Green Scissors Coalition urged House lawmakers to oppose year-round E15, saying taxpayers already spend billions subsidizing the ethanol industry through the RFS and that loosening E15 rules would add more taxpayer cost while worsening air, soil and water quality. EPA’s RFS webpage was last updated June 8, 2026, and the same administrative machinery remains in place even as critics argue the original energy-security rationale has been overtaken by domestic oil output and a much more complex fuel market.