A year-long study by San Diego Gas & Electric (SDG&E) studying two converted plug-in hybrid electric vehicles with 5 kWh Li-ion battery packs found that the converted PHEVs achieved a 60% increase in gas mileage, a 37% decrease in carbon dioxide (CO2) tailpipe emissions, and an 18% reduction in fuel costs compared to the same cars prior to conversion.
In response to increased interest in alternative-fueled vehicles, SDG&E evaluated the two standard hybrid vehicles for six months and, using the same pool of drivers, evaluated the converted plug-in hybrid vehicles for an additional six months.
Among the study’s results are:
The plug-in hybrid achieved 67 mpg, a 60% increase over the standard hybrid’s 42 mpg and a 205% increase in mpg compared with a standard car at 22 MPG;
The plug-in hybrid achieved a 37% reduction in CO2 tailpipe emissions when compared with a standard hybrid and a 67% reduction compared with a gasoline-powered car; and
The plug-in hybrid had a monthly fuel cost of $94, an 18% reduction from the fuel costs of a standard hybrid ($115) and a 57% reduction when compared with a gasoline-powered car with a monthly fuel cost of $219 at $3.85 per gallon.
Original equipment manufacturer plug-in hybrids are expected to be delivered to showroom floors across the nation in late 2010 and the efficiencies are expected to be higher than those demonstrated in SDG&E’s study, the utility said.