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Drilling the Cornfield



The Environmental Protection Agency (EPA) announced Dec. 1 that it would defer deciding on a request by Growth Energy, an ethanol trade group, to increase the allowable blending percent of ethanol in gasoline from 10 to 15 percent. Public Citizen commented in July on the petition, strongly urging that EPA deny the request for a waiver. EPA’s is expected to make a final determination in June 2010.

Distressingly, EPA’s letter expresses that blends of 15 percent ethanol are likely to be approved for vehicles made in model year 2001 or later. Public Citizen strongly opposes this. There are still a large number of vehicles on the road that were built before model year 2001. And preliminary results of the DOE testing suggest that problems with greater ethanol blending aren’t isolated to older vehicles. In a preliminary report, DOE found that 7 of 16 tested vehicles, including two model year 2007 vehicles did not adjust properly to 15 percent ethanol. Running in these conditions could cause costly damage to emissions control systems.

Vehicles that cannot adjust to higher ethanol content and run the higher blend anyway are at risk of vapor lock, a condition created when water, which dissolves in ethanol, builds up in the gas line and prevents combustion, as well as corrosion damage to engine and fuel system parts. Many manufacturers specifically advise vehicle owners from fueling with blends of ethanol greater than 10 percent. Drivers who experience this damage may find themselves failing emissions inspections, and having to pay the cost of replacing the emissions control system out of pocket, since manuals state that running higher ethanol percentage may void the warranty.

What’s worse, EPA has considered this application from the ethanol industry perspective of the “blend wall,” an artificial problem generated when the mandated volume of ethanol can’t be integrated into the fuel stream, because no vehicles exist to consume it and no infrastructure exists to dispense it. The volume mandates for ethanol first created in the 2005 energy law, and expanded to 36 billion gallons in the 2007 energy law might spark investment in producing ethanol, but can’t do anything to increase its consumption.

Forcing a fuel on the market to meet an arbitrary volume goal without considering whether it is a worthwhile alternative could place vehicle owners at risk of doing costly damage to their vehicles. Ethanol has dubious environmental benefits, and is supported by expensive subsidies. Increasing ethanol blending to 15 percent could also have a negative impact on air quality. EPA must consider raising the ethanol content of gasoline in a global context that considers whether ethanol is the right policy for achieving national goals of reducing greenhouse gas emissions and cutting oil dependence.

Ethanol’s dubious ability to combat climate change is based on a web of interconnected factors almost as complicated as climate change itself. The 2007 energy law required that ethanol’s lifecycle greenhouse gas emissions be calculated, due to a definition of “advanced biofuels” that took into account reduction of lifecycle greenhouse gas emissions. This was a major improvement over the 2005 law, spurred on by research, published in early 2007, that suggested the lifecycle greenhouse gas emissions of ethanol from food crops were much more significant than previously estimated. But lifecycle analyses reveal that conventional corn-based ethanol might not provide much climate benefit, if any.

Advanced biofuels – ethanol produced from cellulose, a non-edible plant matter that can include crop and forest residues, or ethanol or hydrocarbon fuels derived from or produced by genetically-engineered algae – have not yet made significant inroads to the ethanol market. And cellulosic ethanol’s long-term viability is based on a significant underestimate of the value of cellulose feedstocks. For example, crop residues are traditionally used as a means of replenishing nutrients in farm fields for the next year’s crop. If crop residues are used for fuel, then farmers will have to use either more land or more chemical fertilizers, resulting in increased greenhouse gas emissions. More advanced approaches, such as algal biofuels aren’t technologically mature enough to be relied upon.

But dumping a lot of money and energy into ethanol, even advanced ethanol, might not ever be a good idea. And these blends of ethanol and gasoline between 10 and 25 percent (called “mid-level” blends) are actually more harmful than gasoline from an air quality standpoint, resulting in increased emissions of smog-forming ozone and particulate matter. Some have argued that if we are designing microbes and algae to produce fuels, that there are better fuels than gasoline or ethanol that would be more consistent with our existing fueling infrastructure and would be more compatible with cars on the road today.

Lena Pons is a transportation policy analyst for Public Citizen.

4 Comments leave one →
  1. 12/15/2009 8:43 pm

    Have you read the RFS portion of EISA 2007? It is a very minor portion of the act. If you had read that portion of the act you would know that the act is only concerned with E85. Lesser blends are never mentioned in the act and it is clear that the hard coded production quotas within the act can only be met by E85 production, distribution and use. All of the corporate welfare in the act is for E85, there are no incentives or corporate welfare in the act for lesser blends, nor are there any requirements for ethanol to be in all of our gasoline. EISA 2007 is not a mandatory E10 law.

    • Lena Pons permalink
      12/16/2009 9:26 am

      It’s true that the 2007 energy law did not mandate E10, but it does mandate a volume of ethanol that cannot be met by E85 consumption alone. Also, many states began banning the use of methyl tert-butyl ether (MTBE) to meet air quality requirements for summer blend gasoline, and have turned to E10 as an alternative. Currently, most of the gasoline sold in the U.S. is E10 as a result of this and pressure on gasoline distributors to blend a sufficient volume of ethanol in gasoline. The capacity of this blending alone will not meet future volume requirements as mandated in the 2007 energy law, therefore ethanol manufacturers and fuel blenders have looked to intermediate ethanol blends (e.g. E15) to make up the difference.

      • 12/19/2009 7:50 pm

        “It’s true that the 2007 energy law did not mandate E10, but it does mandate a volume of ethanol that cannot be met by E85 consumption alone.”

        What? E85 is the ONLY WAY that the ethanol mandates of EISA 2007 can be met! How do you propose that the ridiculous ethanol quotas be used past 2013 when all of the gasoline in the US is E10. Even if it were E15 there will be a blending wall by 2015 at the latest. Since all of the corporate welfare in the act is for E85 and E10 is not mentioned it is clear that taking all of the gasoline in the country E10 is an unintended consequence, that will unfortunately have some serious economic and public safety consequences.

        “Also, many states began banning the use of methyl tert-butyl ether (MTBE) to meet air quality requirements for summer blend gasoline, and have turned to E10 as an alternative.”

        Balony. When ethanol is needed to replace MTBE as a seasonal oxygenate, it is only necessary at less than 3%, it was never required as E10. BTW, it was required during the winter, not the summer, and most of the urban areas that had an EPA requirement have phased out those requirements because new cars and RFG gasolines took care of the problem. In my state Portland, OR was one of those areas that used to require a winter oxygenate, but that was dropped years ago.


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