blends

Ethanol use in the U.S. rose sharply in recent years due to public policy and a spike in petroleum prices, and remains high. Public support for ethanol includes mandated minimum levels of use nationwide. However, rather little is known about consumer demand for ethanol and much less about demand by type of blend and ethanol source. We used trial survey data and conjoint analysis to overcome the lack of historical data on consumers’ preferences for ethanol blend fuels. Preliminary findings based on responses from vehicle drivers in Missouri suggest that price is the primary factor behind fuel preferences. The disclosure of ethanol originated from woody feedstocks had a significant effect on preferences ceteris paribus. Ethanol blends of 20 percent had a negatively non-significant statistical effect compared to no-ethanol fuels or those with a 10 percent content. These findings will be tested using different models expanded to a nationwide pool of motor vehicle drivers.

This report is an update of the original version, which was published in October 2008. This updated report includes results from the complete 16-vehicle fleet (the original report included only the first 13 vehicles tested) as well as corrections to minor errors identified in some of the originally reported data. Conclusions drawn from the complete dataset are nearly identical to those from the
original 13-vehicle fleet but with increased statistical confidence.

In summer 2007, the U.S. Department of Energy (DOE) initiated a test program to evaluate
the potential impacts of intermediate ethanol blends on legacy vehicles and other engines. The
purpose of the test program is to assess the viability of using intermediate blends as a contributor to meeting national goals in the use of renewable fuels. Through a wide range of experimental activities, DOE is evaluating the effects of E15 and E20—gasoline blended with 15% and 20% ethanol—on tailpipe and evaporative emissions, catalyst and engine durability, vehicle driveability, engine operability, and vehicle and engine materials.