Currently most refiners produce a sub-octane unfinished gasoline lacking oxygenates called blendstocks for oxygenate blending (BOBs). They then blend ethanol into gasoline for purposes of boosting gasoline octane levels. Ethanol has an octane value of 115 (R+M/2) while finished gasoline’s pump octane value ranges from 87 – 93.41 Ethanol also has a value as a gasoline extender when blended into the gasoline pool.
Other properties of ethanol, such as its volatility and low sulfur and benzene content, influence its value to refiners. Over the waiver period requested by the states, each refiner is expected to make decisions about ethanol blending independently, in light of the value they place on these factors and the complexity and uniqueness of each refinery. Where the blending of ethanol is profitable to refiners we expect that they would continue to blend ethanol into the gasoline pool even in the absence of a renewable fuel requirement (emphasis added).
At current ethanol and crude oil prices, the blending of ethanol into gasoline is an economically beneficial practice for refiners, and based on forecasts used by the EPA this is expected to continue through at least 2013. However if that were to change and blending ethanol into gasoline was no longer an economically beneficial practice for refiners, the EPA believes that the challenges at both the refinery level and in the refined product distribution system would be significant deterrents to reductions in ethanol blending in response to a one-year waiver.
To reduce their use of ethanol refiners would have to a) seek alternative high octane blend stocks or b) significantly adjust refinery operations to make up for the volume and octane increase they currently receive from ethanol. In addition logistical challenges to the refined product distribution system would also have to be overcome in parallel with the necessary refinery operation changes.
Given the significant investments refiners have made in adapting their production and distribution systems to the availability of ethanol, it appears unlikely that they would be able to accomplish the changes necessary to significantly reduce the amount of ethanol used for the 2012-2013 corn marketing year. This is confirmed by a comment from the American Petroleum Institute, Chevron, and Marathon Petroleum Company stating that a one-year waiver would be unlikely to result in a significant decrease in ethanol blending.
Without a reduction in demand for ethanol by refiners, little would be gained by granting the waiver.
Source: Daryll E. Ray and Harwood D. Schaffer, Agricultural Policy Analysis Center, University of Tennessee