Nissan has joined forces with the City of New York to unveil a fleet of electric cars that will be put to use as taxis in the Big Apple. The six Nissan Leaf taxis are part of a test program and a larger goal from New York Mayor Michael Bloomberg that would see electric cars make up a third of the city's taxi fleet by 2020.

The experiment, launched in celebration of Earth Day earlier today, will give the city as well as others around the country an idea of how reliable electric cars can be under such strenuous usage scenarios. Nissan said the cars in question will have a range of roughly 100 miles which should cover the average taxi drivers' shift of 70 miles.

Of course, mileage can and will vary between cab so in order to prevent the cars from running out of juice during a shift, Nissan will install quick charging stations around the city to enable drivers to fuel up between and during shifts if need-be.

The six-car fleet is expected to hit the streets this spring, ahead of the debut of the Nissan NV 200 van later this year. Known as the Taxi of Tomorrow, the NV 200 beat out several others in a competition to standardize the New York taxi fleet last year.

David Yassky, taxi and limousine commissioner, said an electric version of the NV 200 should be available soon although not before the official launch of the regular NV 200 cabs later this year.