Today in Energy

December 8, 2011

Gasoline with higher ethanol content getting closer to U.S. drivers' fuel tanks

graph of Ethanol share of U.S. motor gasoline, January 2009-August 2011, as described in the article text

U.S. gasoline blended with up to 15% ethanol by volume, known as E15, was approved for use in all model year 2001 and newer light-duty vehicles by the Environmental Protection Agency at the beginning of 2011, but E15 gasoline still has several hurdles to clear before it can be sold at your local service station.

When drivers pull up to the gasoline pump, the motor fuel they usually find is blended with 10% ethanol. This fuel, known as E10, has been around for more than three decades and now accounts for well over 90% of the total U.S. gasoline market. EPA determined that E15 would not harm the engines in cars and light-duty trucks manufactured during the 2001 model year and later. Flex-fuel vehicles already use gasoline blended with 85% ethanol. Ethanol's share of total U.S. gasoline demand topped 10% in August 2011 (see chart above) due to E85 contributions, based on the most recent EIA monthly data.

Increasing the amount of ethanol in gasoline is one way to absorb more renewable energy in the U.S. motor fuel mix, as called for by the renewable fuels standard, which requires that U.S. use of ethanol and other renewable fuels slowly rise to 36 billion gallons a year by 2022. The 2011 requirement is 13.95 billion gallons.

The EPA ruling was significant for the ethanol industry, but it was only the first of many hurdles for the higher-blended gasoline before it could be put into the market. Hurdles include:

  • EPA also had to approve a new pump label for E15, so consumers would not be confused over what gasoline they were buying. E15 is not approved for older vehicles, boats, lawnmowers, chain saws or snowmobiles. The pump label was issued on July 25 (see below).
  • image of E15 pump label, as described in the article text
    Source: U.S. Environmental Protection Agency, E15 (a blend of gasoline and ethanol).

  • Because it is a new blend of gasoline, fuel manufacturers that want to sell E15 have to register it with EPA. Before E15 can be registered, manufacturers are required to submit to EPA information on the emissions and health effects of their E15 product. If adequate health data are not available, EPA would then require manufacturers to conduct health tests. EPA said it is in discussion with E15 manufacturers, but has not yet received a complete registration application.
  • To gain market share, E15 will also have to overcome laws and regulations in about three dozen states that restrict gasoline with more than 10% ethanol. However, it is uncertain how quickly retailers will invest in the infrastructure to sell E15 even if these legal hurdles are overcome. Service station owners, from independent retailers to major chains, have to decide if they want to switch over to sell only E15 gasoline, continue to sell only E10 gasoline, or make both types available.
  • Selling both E10 and E15 would require a station to have separate pumps and storage tanks for each type of gasoline or to install more expensive blender pumps that could dispense both fuels. Where tank space is limited, station operators may not be able to offer the full range of fuel grades at each level of ethanol content. One problem is some stations have older pumps certified by Underwriters Laboratories (UL) to dispense only E10 gasoline. UL is concerned that gaskets and seals on older pumps could degrade and leak if they are exposed to gasoline with more than 10% ethanol.
  • Another potential hurdle for getting E15 into the marketplace is that the Clean Air Act does not extend to E15 fuel the waiver given to E10 for gasoline volatility limits intended to address ground-level ozone pollution during the summer. This means that a special gasoline with low evaporative emissions will be needed to blend with E15 during the summer period from June 1 to September 15. However, this type of gasoline is not readily available in all parts of the country.