One of the biggest hurdles to getting more electric cars on the road is " range anxiety," the worry people have of their car battery dying before they get to a charging station. A new study should help brush those fears aside. Most American drivers do not go beyond the distance that today's electric cars can go on a single battery charge in one day, the study found. In fact, 87 percent of the vehicles on the road could be replaced by low-cost EVs on the market today even if they were only charged overnight, say the MIT researchers who conducted the study published in Nature Energy. If this large-scale swap were to happen, it would lead to roughly 30 percent less carbon emissions even if the electricity were coming from carbon-emitting power plants. The researchers analyzed daily vehicle travel patterns across the U. S. by bringing together two large datasets. One, the National Household Travel Survey, gave them information on millions of trips made by all kinds of cars. The other included detailed GPS-based data collected by state agencies that measured second-by-second velocity of each kind of trip. The researchers also factored in ambient temperature and inefficient driving behavior to calculate the energy consumption of each trip: extensive heating or cooling and driving habits such as hard acceleration zap energy and can reduce driving range. Taking the 2013 Nissan Leaf as an example of an affordable EV on the market, the researchers found that it could meet the driving needs of 87 percent of vehicles on a single day. That number could go up to 98 percent as batteries meet new capacity targets set by the Advanced Research Projects Agency-Energy. What about the remaining 13 percent of trips? The researchers admit that electric cars might not cut it for longer trips, such as vacation travel. For those times, they suggest that people in a two-car household could use their gasoline-powered vehicle, or they could rely on car-sharing or renting services. The data covered the country's 12 major metro cities, from dense urban areas such as New York to sprawling cities like Houston. Surprisingly, the adoption potential of electric vehicles was pretty similar across these diverse cities: it only varied from 84-93 percent. " This goes against the view that electric vehicles—at least affordable ones, which have limited range—only really work in dense urban centers," said the study's lead author Jessika E. Trancik in a press release. Trancik and her colleagues admit that addressing range anxiety might not be enough to boost EV sales. "Satisfying consumer preferences for vehicle performance and aesthetics will also be important, as will financing options to offset the purchase price," they say in the paper.

单选题 What has the new study found?

单选题 What do we know about electric cars today?

单选题 The word "swap" (Para. 2) is closest in meaning to______.

单选题 According to the passage, which of the following has not been considered by the MIT researchers?

单选题 What information do Trancik and her colleagues offer on the use and marketing of EVs?