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.

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. 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.

—Mike Coleman, Project Manager at the USCG R&D Center

Testing will take place at the US Coast Guard Training Center in Yorktown, Va.

Isobutanol is a biofuel that compared to ethanol, has higher energy density, lower Reid Vapor Pressure (RVP), lower oxygen content, and does not present phase separation issues seen with ethanol.

Source: Gevo.

In addition to its use as a “drop-in” gasoline blendstock, isobutanol can be readily converted to isobutylene, a precursor to a variety of bio-hydrocarbon transportation fuel products such as iso-octene (gasoline blendstock), iso-octane (alkylate — high-quality gasoline blendstock and/or avgas blendstock), iso-paraffinic kerosene (IPK, or renewable jet) and diesel.

Gevo has developed a renewable method to produce a 98+ percent–purity isobutanol product using sugars from any available source. The initial plan is to convert existing US corn ethanol plants into isobutanol plants for a fraction of the cost to build new facilities. Gevo also plans to upgrade some of these facilities to produce an isobutanol that will be classified as an advanced biofuel as defined by EPA under the US Energy Independence and Security Act (EISA), to allow cellulosic sugars to be used as a feedstock as they become cost competitive, and to allow multiple products to be generated.