An optimistic new study by the Electrification Coalition says that as many as 14 million electric cars could be on U.S. roads by 2020 and account for 75% of all light-duty miles driven in the country by 2040.

Called the Electrification Roadmap, this highly ambitious plan has the backing of a consortium of companies including Nissan, FedEx, Coda Automotive and Coulomb Technologies. Basically, this coalition says that one in four cars on the road will be an EV by 2020.

The Electrification Coalition concedes that to achieve this lofty goal the federal government will have to provide strong incentives and pursue policies that encourage the spread of plug-in vehicles.

The group proposes building “electrification ecosystems,” meaning it wants to introduce “all the separate elements, from cars to infrastructure, simultaneously” to several major U.S. cities. The idea is to use government support to create pockets across the country that can demonstrate the benefits of plugging in.

Nissan CEO Carlos Ghosn thinks a target of 1 million EVs on the roads by 2015 is more realistic.

Still, the group flouts one wild card, which is the price of oil. Spikes in the cost of gas could spur consumers toward fuel-efficient cars faster than predicted. In the (unlikely) event that the group was right and the U.S. reaches the 2040 target, oil consumption for passenger cars would drop from 8.6 million barrels per day to 2 million a day.

Group Predicts 14 Million EVs on US Roads by 2020 (Reuters)