The surprise election of Donald Trump as the 45^th President of the United States has sparked concern that the 10-year old Renewable Fuel Standard might come under attack by his administration despite Trump’s repeated comments during his campaign and after his November win that he supports ethanol in US transportation fuel. Ethanol is the primary renewable satisfying the RFS, with biomass-based diesel the second largest contributor in meeting the mandate.

The RFS has several nested categories including cellulosic fuel. The renewable industry’s failure in producing enough cellulosic fuel to meet the mandate—or should we assign blame to unrealistic legislators in setting the target too high—has allowed the RFS to come under criticism.

The high volume requirement for the renewable fuel nested category, overwhelmingly satisfied by corn-based ethanol, is another area of protest against the RFS. The increasing volume required to satisfy this portion of the RFS can’t be met with E10 alone, a 10% concentration of ethanol in gasoline, while restrictions remain for a higher concentration for conventional fuel vehicles. Meanwhile, flex-fuel vehicles that allow for a variety of higher ethanol blends in gasoline have only modestly added to US ethanol consumption.

This reality has triggered adjustments to the statutory volume mandates under the RFS, and also spiked costs for many of the oil refiners that are obligated to meet the mandate through their purchase of Renewable Identification Numbers—the credit used to show compliance with the RFS. RINs, which are generated with the renewable and move through the supply chain with the blendstock, can be separated and sold in the open market. RIN values surged in 2016 in a repeat performance from 2013 when ethanol neared the 10% “blend wall,” prompting the US Environmental Protection Agency to downgrade the volume requirements under the RFS.

Biomass-based diesel, primarily biodiesel made from soya oil, fats and grease while renewable diesel volume continues to increase, has largely been shielded from these criticisms. Indeed, biomass-based biodiesel has moved into the breach, covering volume shortfalls in other nested categories to more closely align annual RFS volume obligations issued by the EPA with the statute.

On November 23, 2016, EPA, the administer of the RFS, finalized 2017 volume requirements for obligated parties—oil refiners and importers of petroleum-based tran...