The Renewable Fuel Standard requires refineries and fuel blenders to sell specific volumes of biofuels set by the U.S. Environmental Protection Agency (EPA) each year. In anticipation of increased ethanol consumption, the U.S. Department of Energy started an engine and passenger vehicle test program in 2007 to determine the impacts of mid-level ethanol blends. In March 2009, EPA received a formal Clean Air Act (CAA) waiver request from the ethanol industry to raise the allowable ethanol content in gasoline for passenger vehicles from 10% (E10) to 15% (E15). EPA approved the E15 waiver request but only for 2001 vehicle model years and newer. E10 remains the limit for passenger vehicles older than the 2001 model year and for other engines and vehicles that use gasoline, such as lawn mowers, motorcycles, and boats.
Before E15 can be sold, many federal and state laws and regulations must be updated. EPA is working through regulations to introduce E15. Other necessary steps include completion of EPA fuel registration by ethanol producers to demonstrate it causes no adverse health effects in accordance with the relevant provisions of the CAA and to develop and make available labels for fuel dispensers.
There are more than 90 state laws and regulations currently limiting sales of E15 in more than 30 states. Some state restrictions in conflict include a 10% ethanol blend cap, state biofuels mandates, technical fuel specification standards, and waivers. It is unknown when the update of laws and regulations to allow E15 sales will be completed. Initially, E15 availability is expected to be in Midwestern states.