From an article by Jeff Anthony, American Wind Energy Association and RENEW Wisconsin board member:
. . . While wind energy is becoming a mainstream source of electricity in the U.S., with a realistic potential of powering 20% of our electric needs by 2030, its ability to play a key role in powering PHEVs [plug-in hybrid electric vehicle] makes for an even brighter future for the clean, renewable energy source. . . .
With widespread deployment, the impact of PHEVs on the transportation sector and the nation would be massive. A study by the Pacific Northwest National Laboratory found that replacing 73% of the U.S. light-duty vehicle fleet with PHEVs would result in a reduction in oil consumption of 6.2 million barrels a day, cutting the need for imported oil by about 50%.
But what would such a heavy reliance on electricity generation for transportation purposes do to aggregate power plant emissions? A joint study by the Electric Power Research Institute (EPRI) and the Natural Resources Defense Council found that if 60% of light vehicles in the U.S. were replaced by plug-in vehicles by 2050, electricity consumption would rise only about 8%. The net gain from significantly reducing oil use for transportation—while only marginally increasing the use of fossil fuels to produce electricity—would translate into net carbon dioxide reductions of 450 million metric tons annually—equivalent to taking 82 million cars off the road. And when you bring wind power into the equation, the news gets even better: if the renewable energy resource contributes a greater share to the electricity supply mix that ultimately would recharge the PHEV fleet, any increase in emissions from greater electricity usage can be cut dramatically, making the net emissions reduction even lower.
The primary reason PHEVs result in significant net emissions reductions is that electric motors are several times more efficient than gasoline internal combustion engines. EPRI estimates that while charging, PHEVs will draw only 1.4 kW-2 kW—about the same as a dishwasher. Moreover, in a transportation world that includes many PHEVs, electric rates are likely to be designed to ensure that vehicle charging occurs almost exclusively at night, guaranteeing that PHEVs will use low-cost electricity—while not imposing additional strain on the electric grid during daytime hours of peak electricity usage. And wind energy fits ideally into that part of the equation for another reason as well: wind power output is typically highest at night in many parts of the country. . . .