June 1st marks the beginning of the summer driving season, a time when many regions switch to summer gasoline blends to comply with smog restrictions. But, as fuel retailers have sought to increase the offering of higher ethanol blends, including E15, they have run into a heretofore little known fuel regulation – Reid Vapor Pressure (RVP). For a refresh on why RVP is regulated in the summer, check out EESI’s article on the issue. Essentially, without a RVP waiver for E15, retailers in most regions are unable to sell the blends year round.
The issue has been receiving increased attention from the ethanol industry as they now find themselves with a U.S. gasoline market that is saturated with E10. RVP is regulated to control for smog in the summer months. Adding small amounts of ethanol (10 percent or less) to gasoline raises the RVP rating of gasoline; however, this effect is erased with higher ethanol content. At an E30 blend, for example, the RVP rating of gasoline is lower than ethanol-free gasoline. Additionally, increasing the ethanol content does not contribute to smog formation.
Adding 10 percent ethanol to gasoline raises gasoline’s RVP rating by one psi, to approximately 10 pounds per square inch (psi), according to the National Renewable Energy Lab. Because of this phenomenon, the EPA granted E10 a one psi waiver (commonly referred to as the one pound waiver) in 1992. Currently, higher blends of ethanol, such as E15, do not have a waiver. The ethanol industry, and now many fuel retailers, would like to change that.
According to Growth Energy, an ethanol trade group, there are 830 retail locations in 29 states that offer E15. There is growing interest in expanding fuel offerings at retailers. The timing is right, as gas station owners and fuel retailers can tap into state and federal incentives to upgrade pumps and storage tanks to be compatible with higher blends.
On March 2, a bipartisan group of Senators, led by Senator Deb Fischer (R-NE) and Joe Donnelly (D-IN), reintroduced the Consumer and Fuel Retailer Choice Act (S. 517), which would amend the Clean Air Act to allow for the year-round sale of mid-level ethanol blends, particularly E15.
Lifting the RVP cap has been widely supported by ethanol trade groups. Both independent and major fuel retailers are interested in upping the offering of E15 at gas stations, and the Governors of Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota and South Dakota have all expressed support.
The Senate Environmental and Public Works Committee expects to hold a hearing on the bill in mid-June.
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