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On June 24th, 2016, 39 U.S. senators sent a letter to Gina McCarthy, EPA Administrator, urging her association to ensure that the final 2017 Renewable Fuel Standard (RFS) rule "promote[s] growth in the U.S. biofuel sector and capture economic opportunity rather than drive investment overseas".

The 2017 proposal, which is a fraction below the Congress-envisioned 2007 target when it expanded the RFS of 15-billion-gallons, asks refiners to blend 14.8 billion gallons of biofuels throughout 2017.

In a statement, Bob Dineen, CEO and president of the Renewable Fuels Association (RFA), said: "We thank the lawmakers for their leadership to ensure EPA finalizes a strong RFS that gets the program back on track. In proposing a lower conventional biofuel target for 2017, the EPA is catering to the oil industry by relying upon an illegal interpretation of its waiver authority and concern over a blend wall that the oil industry itself is creating. The RFA has demonstrated just how easy it would be for obligated parties to reach the 15-billion-gallon statutory volume for conventional biofuels next year - through rising gasoline demand, increased E15 and E85 and 2 billion surplus renewable identification numbers available to refiners.

"Meantime, continued uncertainty has caused investments in new technology and advanced biofuel to languish or move overseas. It's time EPA follows the statutory requirement and increase the conventional biofuel target to 15 billion gallons."

US Navy

The US Navy is a key marine consumer of biofuels for its fleet of vessels. Since assuming office in 2009, U.S. Secretary of the Navy, Ray Mabus, has made energy and energy security a priority. He set an aggressive goal for the Department of the Navy aimed at ensuring that, by no later than 2020, the Navy and Marine Corps would obtain at least 50 percent of its energy from alternative sources. It also set a target to reducing marine fuel consumption by 15 percent.

Then, in 2014, the U.S. Departments of Navy, Energy, and Agriculture awarded contracts to three companies to construct and commission biorefineries capable of producing 'drop-in' biofuels to meet the transportation needs of the military and private sector.

Despite receiving public criticism about the cost of biofuels, the US Navy has defended its strategy. Earlier this month, attending the first refuelling of a US warship with biofuels from a partner nation, Mabus pointed out that, in addition to emission reductions, the aim was to ensure that the US and its allies weren't vulnerable to disruptions of traditional fuel supplies and highlighted Russia's threat to cut off Ukraine's fuel supply as an example of that vulnerability.

US biofuel research

The Scripps Institute of Oceanography at the University of California ran the research vessel Robert Gordon Sproul on biofuel for more than a year between September 2014 and December 2015. Experiments showed that when running on biofuel, emissions of NOx were about 13 percent lower that when running on diesel, particularly if the ship was running at lower speeds, (700 and 1,000 revolutions per minute). However, the particle emissions were 35 percent higher for biofuel when the engine was running at higher speeds (1,600 revolutions per minute). Black carbon or soot counts were also slightly higher for biofuel.

A report published by Navigant Research in 2014 suggested that biofuels will make up over 6 percent of the marine fuel and aviation market in the United States by 2024.