An electric car is an automobile that is propelled by electric motor(s), using electrical energy stored in batteries or another energy storage device. Electric cars were popular in the late 19th century and early 20th century, until advances in internal combustion engine technology and mass production of cheaper gasoline vehicles led to a decline in the use of electric drive vehicle. The energy crises of the 1970s and 80s brought a short-lived interest in electric cars, but in the mid-2000s a renewed interest in the production of electric cars took place, due mainly to concerns about rapidly increasing oil prices and the need to curb greenhouse gas emissions. As of March 2012, series production models available in some countries include the Tesla Roadster, REVAi, Buddy, Mitsubishi i MiEV, Tazzari Zero, Nissan Leaf, Smart ED, Wheego Whip LiFe, Mia electric, BYD e6, Bolloré Bluecar, Renault Fluence Z.E., Ford Focus Electric, BMW ActiveE, and Coda. The Leaf, with more than 25, 000 units sold worldwide by March 2012, and the i-MiEV, with global sales of more than 17, 000 units through October 2011, are the world's top-selling highway-capable electric cars. Electric cars have several potential benefits compared to conventional internal combustion automobiles, including: a significant reduction of urban air pollution, as they do not emit harmful tailpipe pollutants from the onboard source of power at the point of operation (zero tail pipe emissions); reduced greenhouse gas emissions from the onboard source of power, depending on the fuel and technology used for electricity generation to charge the batteries; and less dependence on foreign oil, which for the United States and other developed or emerging countries is cause for concern about their vulnerability to price shocks and supply disruption.
