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Gevo, Inc. has begun supplying the U.S. Coast Guard Research and Development (R&D) Center with initial quantities of finished 16.1% renewable isobutanol-blended gasoline for engine testing.

"Gevo's proprietary isobutanol-blended gasoline is truly a drop-in fuel, deliberately designed to be fully compliant with marine fuel specifications, including fit-for-purpose properties," said Patrick Gruber, Gevo's chief executive officer. "Isobutanol's low-water solvency and non-corrosive characteristics will offer consumers a high-performance, renewable biofuel ideally suited for a wide variety of marine engine applications."

The U.S. Coast Guard R&D Center is using the Gevo-blended fuel as part of a 12-month, long-term operational study on marine engines that began in June. The testing is being performed under a Cooperative Research and Development Agreement (CRADA) between the U.S. Coast Guard, Honda, and Mercury and will focus on two of the Coast Guard's platform boats - a 38-foot special purpose craft (training boat) and a 25-foot response boat.

The US Coast Guard completed a 3-month round of testing in Florida earlier this year under the CRADA with Honda engines running on fuel supplied by Gevo which contained 16.1% renewable isobutanol. Engines were run at full throttle for an 8-hour day for several months and then broken down and inspected.

Mike Coleman, Project Manager at the USCG R&D Center stated: "We are pleased so far with our testing of isobutanol as a potential alternative to ethanol as a blend stock in gasoline for marine applications."

According to Gevo, isobutanol is a biofuel that compared to ethanol, has higher energy density, lower RVP, and does not present phase separation issues seen with ethanol.

"All testing so far has been positive, and when the Yorktown tests are completed next year, we expect to have the information available to allow a decision on whether 16.1% Isobutanol fuel blends will be certified for use in the Coast Guard gasoline engine fleet," said Gruber.

"This testing will validate isobutanol-blended gasoline as a clean-burning, homegrown, drop-in fuel for marine applications. As we accelerate our full-scale commercial production efforts at the world's first renewable isobutanol plant in Luverne, Minn., we are extremely excited to be working with a partner like the U.S. Coast Guard to evaluate and develop a product line of high-performance, isobutanol-based fuel blends for the marine engine market," Gruber added.

Testing will take place at the U.S. Coast Guard Training Center in Yorktown, Virginia.