By Joel Beauvais and Steven Croley (April 23, 2018, 11:54 AM EDT) -- The Renewable Fuel Standard, or RFS, has been the focus of sustained policy discussion and resulting uncertainty during the first year of the Trump administration. Over the past year, the administration has floated, and then set aside, several proposals for substantial policy change. The administration has also granted RFS exemptions to a substantial number of small refineries, dampening demand for the tradable credits known as renewable identification numbers, or RINs — which represent production of renewable fuels and are used to demonstrate compliance with RFS requirements — and RIN prices have decreased from approximately $1 in November 2017 to about $0.34 today. The administration meanwhile is conducting high-level policy discussions and considering a number of potential other changes, including allowing sales of E15 (gasoline that is 10 to 15 percent ethanol by volume) during summer months, currently prohibited in most areas of the country....