Though Electric vehicles(EV) are invented to reduce the emission of harmful green house gases but it is being found not so effective..It is  found that increasing the use of EVs is not an effective way to produce large emissions reductions..The researchers ran 108 different scenarios in a powerful energy systems model to determine the impact of EV use on emissions between now and 2050. They found that, even if EVs made up 42 percent of passenger vehicles in the U.S., there would be little or no reduction in the emission of key air pollutants.
                             The energy systems model also showed that key factors in encouraging use of EDVs are oil price and battery cost. If batteries are cheap and oil is expensive, EDVs become more attractive to consumers.
                     So, at present the main requirement is to make popular the EVs among the people, drivers,among the consumers..We need to take steps against this problem...

     Electric cars have been invented recently..They already have achieved more than 180 miles per hour and have established world speed records above 300 mph.  Electric race cars have such a great capacity for speed because they utilize energy more efficiently than internal combustion engines. Explanation is like this:
         Turning gasoline into motion involves multiple steps that transfer motion from pistons to a crank shaft, to a flywheel, through a transmission and other mechanisms to finally reach the wheels. Each step consumes energy before it can become applied as motion, or torque, to the wheels. In an EV, in contrast, the conversion is more direct, from batteries to an electric motor that operates with negligible friction (electic motor still goes through a simplified gearbox and other mechanisms to the wheels). EV motors often provide up to 15,000 revolutions per minute (rpm), compared to less than 8,000 rpm for internal combustion engines (consumer cars usually provide less than 6,000). The high rpm of the electric motor eliminates the need for heavy and expensive transmissions.