EPA would give market boost to butanol, other fuels in proposed rule

Source: Amanda Peterka, E&E reporter • Posted: Wednesday, May 22, 2013

U.S. EPA is proposing to allow butanol that’s been made from corn starch to qualify for credit under the nation’s biofuel mandate.

The decision, released today by the agency along with several other proposed fuel qualifications, could greatly expand the market for renewable butanol, a colorless liquid that can be processed into fuel. It would allow refiners to use the fuel toward their annual advanced biofuel obligations under the renewable fuel standard, the federal policy that requires 36 billion gallons of biofuel be blended into the nation’s motor fuel supply by 2022.

The proposed rule from EPA comes after an analysis of the biobutanol’s greenhouse gas emissions compared with petroleum-based fuel. The rule would also allow ethanol made from corn kernel fibers to qualify for advanced biofuel credits, as well as renewable diesel, renewable electricity and naphtha made from the gas emitted from landfills.

The biotechnology industry praised the decisions, which were posted today on EPA’s website after a seven-month review by the White House was completed Friday (Greenwire, May 20).

“Finalization of new pathways will clear the way for companies to bring innovative technologies to the marketplace,” said Brent Erickson, executive vice president of the Biotechnology Industry Organization’s industrial and environmental section.

Before approving fuels under the renewable fuel standard, EPA is required by statute to analyze their estimated life-cycle greenhouse gas emissions reductions. In order to qualify as an advanced biofuel or biodiesel, a fuel must demonstrate at least a 50 percent reduction in greenhouse gas emissions compared with petroleum-based fuel. Cellulosic biofuel, a subset of advanced fuels, has a higher bar of 60 percent.

EPA has determined that butanol made from corn starch at certain converted ethanol facilities achieves a 51.3 percent reduction in greenhouse gases, allowing it to qualify as an advanced biofuel. The agency based its analysis on information provided by Gevo Inc., an advanced biofuel company that submitted the petition to the agency to include butanol in the RFS.

“We applaud the EPA’s proposed amendments to the renewable fuel standard, including the introduction of new pathway determinations for advanced biofuels such as isobutanol,” Brett Lund, executive vice president and general counsel for Gevo, said in a statement. “Gevo is especially proud to have led the charge for the butanol amendments, reiterating our position as an industry-leading renewable chemicals and next-generation biofuels company.”

Gevo and a joint BP PLC-DuPont Co. venture called Butamax are currently locked in a patent war over the technology and a race to become the first successful company to produce the fuel at a commercial scale. They are both attempting to retrofit existing corn ethanol plants with their technology.

Biobutanol is widely seen as having benefits over conventional ethanol, including a higher energy density and a lower blending vapor pressure. As a drop-in biofuel, it can also be used in existing fuel infrastructure, unlike ethanol, which is blended in small amounts into existing petroleum-based gasoline (Greenwire, Oct. 2, 2012).

As part of its rule, EPA is also proposing to allow corn kernel fiber, or the portion of leftover corn kernel that’s made from cellulosic materials, as an accepted feedstock under the RFS. The agency has proposed adding the fiber to its definition of crop residues, putting it on the same level as corn stover, wheat straw, rice straw and bagasse, a leftover from sugar cane production.

According to the proposed rule, EPA believes that fuel made from leftover corn kernels meets the 60 percent greenhouse gas reduction required for cellulosic ethanol. The agency said it does not believe that allowing the fuel to qualify will greatly increase the amount of corn produced in the country or the demand for corn.

EPA has also made several decisions regarding the gases that are released when materials decompose in landfills. Known as biogas, they typically contain about 50 percent methane and 50 percent carbon dioxide, with small amounts of trace gas.

EPA today is proposing that biogas converted to electricity for use in the transportation sector, such as in electric vehicles, be allowed to qualify as a cellulosic biofuel. The agency found that the production process attains at least an 87 percent greenhouse gas emissions reduction compared with petroleum fuel.

The agency is also proposing to add renewable diesel and naphtha made from landfill biogas as advanced biofuels, and renewable compressed natural gas and liquefied natural gas as cellulosic fuels. EPA will accept public comments on the proposed rule before issuing a final version.