Reducing vehicle energy use and GHG-emissions beyond the level offered by the gasoline hybrid presents a much greater challenge. Under the assumed fuel production pathways, the hybrid, plug-in hybrid, and fuel-cell vehicle each offer a 40-45% [GHG figure] lower than the 2030 NA-SI baseline. These results suggest that without an effective effort to develop cleaner fuel pathways, a transition to alternative fuel powertrains does not deliver a significant CO2 benefit beyond that offered by the gasoline hybrid vehicle.
Note that the 100 km range PHEV60, the pure BEV and the FCV all produce marginally more GHGs than the HEV, based on the US mix of power sources.
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