Featuring transparent solar panel windows to harness solar power and provide panoramic view of the surroundings, the urban taxi also saves space by conjoining to each other and forming a train. The Runner Train can connect up to three cabins with secure wireless commands. Running on multi-level hubless dynamo wheels, the Renault Runner also includes a power converter to accumulate kinetic energy as an added source of power, while intelligent LED lights make it an entirely zero-emission vehicle.
Source: design blog
Renault Runner taxis concept