The internal combustion engine on a hybrid or a plug-in hybrid could be powered by fuels other than gasoline. For example, ethanol or other biofuels such as bio-butanol could be used to power the ICE, completely eliminating gasoline consumption from operating the car itself [1].  The vehicle would run on biofuel and electricity from the grid.

To the best of our knowledge, no HEVs or PHEVs have yet  run on biofuels.  However, we do have information from ICEs running on ethanol.   The computer model uses this information to project the performance of biofuel powered PHEVs[2].  We use cellulosic ethanol as the surrogate for other biofuels in this simulation.  The Argonne National Laboratory GREET model [3] estimates the greenhouse gas emissions, oil consumption and urban air pollution for cellulosic ethanol (and for all other fuels and vehicles in this model).

[1] An ethanol-powered PHEV would still require some fossil fuels to make fertilizer, pesticides, fungicides and diesel fuel used in farming, plus diesel fuel to bring the biomass to the ethanol plant, natural gas or coal to run the ethanol plant, and more diesel to transport the ethanol to the fueling station. Fossil fuel use would be substantially reduced with cellulosic ethanol production.

[2] The computer also modeled biofuel powered ICVs and HEVs.  However, the greenhouse gas reduction and oil reductions with these vehicles were always less than those of the biofuel powered PHEVs, so we only report the best case PHEVs here.

[3] Wang, MQ, “Greenhouse gases, regulated emissions, and energy use in transportation (GREET)”, Argonne National Laboratory.