There is a growing consensus that America’s dependence on oil constitutes a triple threat to its national security, its economic vitality, and its environmental health. But agreement breaks down on the question of how, exactly, the country can best achieve dramatic, near-term reductions in oil consumption. We believe that the greatest potential for transformative change may lie in the emerging technology of plug-in hybrid-electric vehicles (PHEVs), which could become widely available in the United States in five to 10 years if government takes a few smart steps to help spur their commercialization.
Like conventional hybrid-electric vehicles, plug-in hybrids save fuel by using small internal combustion engines in combination with electric motors. But while conventional hybrids charge their batteries with kinetic energy and power generated by their own internal combustion engines, plug-in hybrids, as the name suggests, have cords that can be plugged into standard, 120-volt electrical outlets.
That design — constituting a partial merger of the transportation and electricity sectors — can produce dramatic reductions in gasoline consumption. Equipped with more powerful battery packs than conventional hybrids, plug-in hybrids can travel the first 20 miles or more on battery power alone, without ever firing up their internal combustion engines. That is farther than the average round-trip commute. After that, they can switch to a conventional hybrid-electric operating mode. In all-around driving, plug-ins could thus get between 80 m.p.g. and 160 m.p.g., compared to about 45 m.p.g. for today’s Toyota Prius. The gasoline savings could be even greater if plug-ins were designed to run on biofuels; they could travel 500 miles on a gallon of gasoline blended with five gallons of ethanol. Read more