Nearly 97 percent of U.S. gasoline contains ethanol, but the Environmental Protection Agency (EPA) is not studying the biofuel's impact on climate change and the environment despite a legal requirement to do so.
That's the main finding from a report released Friday by the EPA's Office of Inspector General (OIG), which called out the EPA for failing to update Congress on whether fuels produced from plant matter are hurting or helping the environment. Read the report here.
EPA required to study ethanol under 2005 law
The OIG's report said the EPA isn't fulfilling its requirements under the Renewable Fuel Standard (RFS), a law which requires transportation fuel like gasoline to contain a minimum volume of renewable fuels, like ethanol.
The law -- which was created to reduce greenhouse gas emissions and thereby slow climate change -- says the EPA must provide reports every three years to ensure fuels like ethanol are not harming the environment. But the EPA has not provided such a report since 2010.
Ethanol doing more harm than good?
Environmental groups say that's unfortunate, because ethanol -- particularly the ethanol produced mainly from corn in states like Iowa -- is doing more harm than good when it comes to man-made climate change.
"It's ironic and frustrating that the government promotes the use of corn ethanol in the name of reducing greenhouse gas emissions, and it's just not doing that," Jonathan Lewis, a senior climate policy counsel at the environmental group Clean Air Task Force, told Circa.
Analysis shows ethanol emits more than natural gas
If the EPA had released a study, it would have likely shown that corn-based ethanol actually emits more greenhouse gases than natural gas over its full life cycle, Lewis said.
He made that assertion because of an analysis his group conducted in 2013. That analysis asserts that corn ethanol's net greenhouse gas emissions over a 30 year period are 28 percent higher than the emissions that come from gasoline over that same period. Read the full analysis here.
Biofuel groups disagree
Groups representing the biofuel industry also say they're disappointed that the EPA hasn't released a report on the climate impacts of ethanol -- but they say that the report would show that ethanol is not harming the environment.
"We are confident that once EPA conducts these required studies, they will show that biofuels like ethanol are significantly reducing greenhouse gas emissions, even above the threshold reductions," Renewable Fuels Association President Bob Dinneen told AgriPulse.
The renewable fuel standard is a politically tricky subject.
RFS has strong opposition from environmental groups, oil companies, livestock farmers, and even some humanitarian groups. But it has ever stronger support with Iowa's powerful ethanol lobby, which was long seen as a necessary group to court for presidential candidates. Iowa is key for presidential candidates because it's the first state to vote in the presidential primary.
The ethanol industry's political influence appears to be wavering, however -- Sen. Ted Cruz (R-TX), who opposes the ethanol mandate, won the state.
Trump on ethanol: love it
Ethanol is also still in play for the remaining presidential candidates. While campaigning in Iowa, Republican nominee Donald Trump said he supports the requirement to have ethanol in U.S. gasoline -- and he criticized Cruz for opposing it.
Clinton on ethanol: improve it
Democratic presidential nominee Hillary Clinton has said she supports the ethanol mandate, but wants to get it "back on track."
"We have to get the RFS back on track in a way that provides investors with the certainty they need, protects consumers, improves access to E15, E85, and biodiesel blends, and effectively drives the development of cellulosic and other advanced biofuels," she wrote in 2015.
Earlier this month, Clinton's campaign indicated she'd like to revamp the law if elected president.