NMMA Testing Demonstrates Gevo’s Isobutanol-Gasoline Blend is Superior to E15 Fuel for Boaters

In 2011, the National Marine Manufacturers Association (NMMA) released a report evaluating isobutanol, provided by Gevo, Inc., that shows great promise for it as a petroleum blendstock for the boating industry. NMMA conducted two tests, an emissions test and a product test, to evaluate the effects of butanol-blended fuels in a harsh marine environment. The project aimed to determine if isobutanol could be a better alternative to ethanol blends for the boating industry.

“We are pleased with the results of the isobutanol evaluation and look forward to more testing on this, and other, important alternatives to E15,” says NMMA President Thom Dammrich. “We know E15 causes significant damage to boat engines and therefore rushing it to the market is irresponsible and an unnecessary step, especially in light of the promising test results on isobutanol.”

The emissions tests compared a 16.1 percent isobutanol blend to indolene, the standard gasoline used for engine testing. The test used a sampling unit that was developed for an EPA/NMMA greenhouse gas study. The evaluation showed there was a reduction of carbon monoxide from the isobutanol blended fuel, compared to indolene. The results also show that hydrocarbons and nitrogen oxide emissions were virtually the same between the two fuels.

The emissions tests were not the only positive results seen. When comparing isobutanol to ethanol for use in boating, several of isobutanol’s key benefits emerged: isobutanol can be blended into gasoline at higher percentages than ethanol and, unlike ethanol-blended gasoline, isobutanol blends do not cause phase separation when water enters a boat’s fuel system. This is a critical distinction between ethanol and isobutanol blends.

“It’s great to have another third party verify the benefits of isobutanol,” says Christopher Ryan, Ph.D., President, COO, and CTO of Gevo. “The product attributes of isobutanol, made in retrofitted ethanol plants, can solve the problems associated with current generation biofuels. Isobutanol is compatible with all gasoline engines and infrastructure like pipelines and fuel pumps. These benefits make it a very promising biofuel additive that can help the nation achieve greater energy independence and align the interests of farmers, ethanol plant owners, refiners, engine manufacturers, and consumers.”