Starting on May 1, E15 gasoline will be more widely available, thanks to a waiver issued by the United States Environmental Protection Agency (EPA), which will temporarily halt seasonal restrictions on the use of the higher-ethanol containing fuel. The move is aimed at lowering gasoline prices, which have escalated since the U.S. began its attacks on Iran earlier this year. But the waiver also comes with some downsides. E15 can damage some engines, plus worsen summer smog— both reasons why it’s currently banned in many places during warmer months. “Also, E15 can degrade faster than E10, due to the higher ethanol content,” says automotive expert Steve Haney. “It may not be a good idea to fill up with E15 if you do not drive frequently, or if you are going to put your vehicle into storage.” Here’s what to know about E15 gas, and how it will affect your car, motorcycle, lawn-care equipment and off-road vehicles. What Is E15 Gas? E15 is a blend of gasoline that contains 15% ethanol and 85% gasoline.…