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Increasing Biofuel Deployment and Utilization through Development of Renewable Super Premium: Infrastructure Assessment

This report evaluates infrastructure implications for a high-octane fuel, i.e., a blend of 25% denatured ethanol and 75% gasoline (E25) or higher (E25+), for use with a new high-efficiency type of vehicle. E25+ is under consideration due to federal regulations requiring the use of more renewable fuels and improvements in fuel economy. The existing transportation fuel infrastructure may not be completely compatible with a mid-level ethanol blend (blends above E15 up to E50). It is anticipated that a mid-level ethanol blend will face many of the same hurdles as E15, and a fuel above E25 will face additional barriers. Three questions need to be considered when introducing a new fuel to existing infrastructure: Is the infrastructure it compatible? Is it listed by a third party? Is it approved?

A significant amount of research and regulatory action has addressed these concerns with positive progress towards enabling the use of ethanol blends above 10% ethanol (E10) in existing and upgraded equipment. The U.S. Environmental Protection Agency’s Office of Underground Storage Tanks biofuels guidance allowed tank and associated equipment manufacturers to issue statements of compatibility (EPA 2011). This has resulted in the determination that the majority of existing tanks are capable of storing blends of up to E85 (a marketing term for high-blend ethanol [51%–83%]) or E100 (denatured fuel ethanol). Past research on ethanol fuels and issues with the introduction and use of ultra-low sulfur diesel led refueling equipment manufacturers to upgrade sealing materials in their products for safe and reliable performance over a range of fuels. However, although gasoline equipment is being designed to be more robust across a broader range of fuels, the Petroleum Equipment Institute stated that new stations are not opting to install E25 or E85 listed or manufacturer-approved equipment due to the greater cost of such equipment and the expectation of low demand for ethanol blends above E10.

The general consensus among industry groups and equipment manufacturers is that it will be easier and less costly to deploy fuel containing ethanol up to E25 than an E25+ fuel. Increasing the blend level will be met with reluctance by manufacturers, who have not yet profited from the development of E25 and E85 products. Equipment manufacturers interviewed in this study suggested a blend above E25 could use their E85 products. While this would be practical because this equipment is available, it is challenging for the marketplace as the price differential between E10 and E25 equipment is negligible compared with the price premium for E85-listed products. Table ES-1 summarizes estimated minimum costs for offering E10+ fuels at a retail station.

And while storage tanks may be compatible with these blends, a typical station will have three storage tanks: one dedicated to diesel and the other two storing regular and premium gasoline to offer regular, mid-grade (made by blending from the two tanks), and premium. In some instances, a station may have a tank dedicated to mid-grade storage that could be used to store an ethanol blend. Incorporating a new ethanol blend into the system presents a challenge to the station operator’s business model and cash flow. A station would need to decide between using an existing tank or adding a new tank.
Perhaps the most significant barrier is that stations are not required to keep records of equipment. This makes it difficult to determine if existing equipment is compatible with various ethanol blends. In addition, retail station owners have concerns about their liability in the event of misfueling. Small, independent retailers (which represent 63% of the stations) are unlikely to

K. Moriarty , M. Kass , T. Theiss
Contact Person
Tim Theiss
Contact Organization
Oak Ridge National Laboratory
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Bioenergy Category
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