Hybrid Taxi Cabs Arrive in Chicago
Chicago jumps on the hybrid taxi bandwagon, putting its first Ford Escape Hybrid Taxi on the road. San Francisco and New York already hav...

In Chicago, a city rule was put into effect on July 1st. It requires taxicab owners to license one hybrid or alternative fuel vehicle if they have 50 taxicabs on the road.
Cab drivers usually have to pay for the gas, so they love driving more fuel efficient vehicles. But its the taxi companys that need to purchase the vehicles in the first place. They need to be convinced of the cabs reliability and/or convinced of its environmental benefits.
Source: Cab firm adds city's first fleet-based hybrid taxi :: CHICAGO SUN-TIMES