September 22 marks the autumnal equinox and the official end of summer. But for approximately 330 gas retailers, the season ended last week, on September 16—a day celebrated as “E15 Day” in Minnesota and Iowa, as well as in several U.S. cities. The day marks the end of summer blend restrictions based on Reid Vapor Pressure, meaning that E15, which contains 15 percent ethanol, can be sold again to all Model Year 2001 or newer cars.

Reid Vapor Pressure, or RVP, is regulated during the summer months to reduce the formation of surface ozone and smog. For more information on RVP regulations, see EESI’s article Summertime, When the Living’s Easy. Essentially, EPA requires summer blends to have a RVP of no more than 9 pounds per square inch (psi). E15, which has an RVP rating around 10 psi, doesn’t qualify, and so can’t be sold year round.

The One Pound Waiver

While neat ethanol actually has a very low RVP rating (2 psi), the chemical interaction between small volumes of ethanol and gasoline causes RVP to increase, putting E10 at around 10 psi. EPA granted E10 a one psi waiver (commonly referred to as the one pound waiver) in 1992, but E15 doesn’t receive the same waiver, despite having a similar RVP rating.

This limits its availability to consumers, as many retailers see the need to adjust practices and change signage twice a year as an excessive hassle, choosing instead to simply not offer the fuel. This limits consumer choice, as E15 has been approved for 80 percent of the cars on the road today by EPA, and tends to be between two and ten cents cheaper than regular gasoline.

Pushing for Year-Round E15

Gas retailers and biofuels industry groups alike have pushed for the RVP waiver to be extended to blends like E15. “While the EPA has the authority to grant E15 the same waiver, they have refused to do so—even though higher blends such as E15 help reduce smog and emissions,” said Emily Skor, CEO of Growth Energy. “The initial waiver for E10 was granted 26 years ago, long before E15 was even part of the discussion. Now is the time for EPA and Congress to act and update our fuel regulations to match the market realities of the 21st century.”

A recent pipeline leak that led to gasoline shortages in several states highlighted the necessity of higher ethanol blends year round. Skor said of the incident, “This just reinforces how dangerous our singular dependence on gasoline is and why increased blends must be added to our nation’s fuel mix to ensure stability and savings.”

Several governors have also taken up the push to expand the availability of E15 year round. Last week, just a few days before the summer blends requirement lifted, a bipartisan group of governors from Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, and South Dakota sent a letter to the EPA, requesting the waiver be extended to higher blends. The letter reads, “EPA’s disparate handling of E10 and E15 with regard to fuel volatility regulation is stifling the widespread adoption of E15 and mid-level ethanol blends.”

Monte Shaw, executive director of the Iowa Renewable Fuels Association, applauded the governors’ letter, saying, “Many retailers have cited the inability to offer E15 as a registered fuel year-round as the number one barrier to providing consumers with that lower-cost, cleaner-burning option. Eliminating this quirk in federal regulation would be a real game changer.”

Author: Rebecca Chillrud

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