WASHINGTON -- If motorists used rechargeable "plug-in" hybrid-electric vehicles in large numbers, the United States could see a significant drop in greenhouse gas emissions by the middle of the century, according to a study released yesterday.
Researchers estimated that with a market share of about 60 percent or more plug-ins, the vehicles could help eliminate approximately 450 million metric tons in greenhouse gas emissions a year by 2050. The reductions would be the equivalent of removing 82 million passenger cars, or about one-third of the cars currently on the road.