In-Use Volatility Impact of Commingling Ethanol and Non-Ethanol Fuels

An analysis of the potential Reid Vapor Pressure (RVP) impacts of the commingling of ethanol fuels with non-ethanol fuels has been done. This analysis includes a computer model that tracks such variables as owner brand loyalty, fill-up patterns, ethanol fuel market share and percent ethanol in the fuel tank to determine the RVP boost that is associated with the use of ethanol as a gasoline oxygenate as it intermingles with non-ethanol fuels in vehicle fuel tanks. Results indicate that the use of ethanol oxygenated fuels can cause, in some cases, a significant increase in gasoline RVP, thus leading to higher evaporative emissions.