There may be some movement on the drive to bring E-15 to gas pumps year-round. At a stop in Iowa this week, President Trump signaled his support of the idea:In the campaign, I promised to support E15 all year round. In hot summer weather, E-15 fuel evaporates faster than regular gas, which is why its use has been restricted in some high-smog areas. The question of allowing E-15 year-round has caused debate among Republicans, with oil and gas interests on one side and farm groups on the other. President Trump has supported year-round E-15 as a way to boost demand for U.S. corn and reduce reliance on foreign energy.