Governors' Biofuels Coalition

Gasoline containing 15 percent ethanol will not harm car engines or cause vehicles to become stranded on the side of the road, a Department of Energy laboratory has concluded after an exhaustive review of existing research on the fuel.

The National Renewable Energy Laboratory report released yesterday found no significant difference between using E15 and using gasoline containing 10 percent ethanol. E10 makes up about 95 percent of the fuel used to power cars today.

The report was most critical of studies by an oil- and auto-industry-funded group that found using E15 would damage the engines and fuel system component of popular vehicles. Those studies have been widely cited by opponents of the renewable fuel standard, the federal policy that mandates increasing yearly levels of ethanol use.

In all, NREL reviewed 43 different studies that examined the use of E15 in vehicles with model years 2001 and newer. The Renewable Fuels Association, which sponsored the work by the national lab, hailed the findings as bringing “important context and scientific credibility back to the debate over E15.”

“It’s time for Big Oil to stop using actors to scare people about E15,” said Bob Dinneen, president and CEO of the association. “It’s time they start paying attention to the overwhelming data and real-world experience demonstrating the efficacy of E15.”

In 2010 and 2011, U.S EPA issued waivers of Clean Air Act fuel regulations that allowed E15 to be sold in the market and help refiners meet their obligations under the renewable fuel standard; the RFS as written requires refiners to blend more than 10 percent ethanol into the petroleum-based fuel supply. A Kansas gas station last summer became the first retailer to sell E15, and since then, about 40 gas stations in nine states have begun to sell the fuel.

But EPA’s decision to allow the fuel to be sold to cars with model years 2001 and newer has come under fire by automakers and the oil industry, which say that Department of Energy testing on the fuel was inadequate and EPA was too hasty in issuing its approval. They have issued their own studies, conducted by the Coordinating Research Council, that found that using the fuel would mean more trips to the mechanic for engine and fuel system problems.

In its report, NREL reviewed the studies done by the CRC as well as those performed by the University of Minnesota, the Minnesota Center for Automotive Research, the Department of Energy and others. Thirty-three of the studies presented new research, while 10 were themselves reviews of existing data.

The various studies examined materials compatibility, engine and fuel system durability, exhaust emissions, catalyst durability, effect on on-board diagnostics and evaporative emissions. NREL said that studies were evaluated on the quality of science, relative level of aggressiveness for various test conditions and importance of the test results.

NREL found that E15 does not cause corrosion on various types of steel and has no relation to engine light malfunctions. There were small or nonexistent differences in evaporative emissions from vehicles using E10 and the higher ethanol blend, and no significant change in combustion or exhaust temperatures using E15.

“The main conclusion from our analysis is that the data in the 33 unique research studies reviewed here do not show meaningful differences between E15 and E10 in any performance category,” the national lab said.

NREL saved its strongest criticism for the Coordinating Research Council studies that found using E15 causes engine failure and fuel system damage. The group’s engine durability study, which found that two car engines used in popular vehicles would fail on E15, was “intended to maximize the number of failures” and chose vehicles that did not use new technologies to improve performance, NREL said.

The lab also said that the engine study used a faulty indicator of failure: leakdown, or the percentage of air found to be leaking out of engine cylinders. According to NREL, the study used an extremely restrictive leakdown failure limit, 10 percent, that is not representative of what engine manufacturer specifications, as well as failed to inspect engines for leakdown prior to the test to establish a control.

NREL also criticized the study for not using E10 as a baseline and for assuming certain data points without testing. The Coordinating Research Council’s fuel system study was also inconsistent in its methodology, NREL said.

“When these factors are taken into account, the conclusion that engines will experience mechanical failure when operating on E15 is not supported by the data,” the lab said.

Monte Shaw, executive director of the Iowa Renewable Fuels Association, said that the study should be the “final nail in the coffin” for the oil- and auto- funded studies. Shaw last week drove to Washington, D.C, to release his group’s own testing results that found flaws with the studies (Greenwire, Oct. 3).

“Big Oil has consistently pointed to two CRC studies as a basis to outrageously claim that E15 will cause engine damage and leave motorists in harm’s way,” he said. “IRFA’s real-world testing data combined with today’s NREL analysis proves Big Oil’s irresponsible statements on E15 cannot be trusted.”

Bob Greco, director of downstream operations for the American Petroleum Institute, last week defended the Coordinating Research Council’s studies in an open letter for the Iowa ethanol group. Auto experts, he said, have been using leakdown for years to ensure that vehicles don’t fail. Overall, the CRC testing is a “clear scientific basis for auto manufacturer concerns.”

“Some engines and fuel systems passed the E15 tests and some failed. Some even passed using E20,” he said. “The bottom line is that there are millions of vehicles on the road today that weren’t designed or warranted to use fuel with ethanol content greater than 10 percent, and the CRC research confirms that they could be put at risk by using E15.”

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