A system is disclosed having a primary vehicle and a secondary vehicle that is carried by the primary vehicle when not in use. The system further includes at least one of an immobilizing device to immobilize the primary vehicle if the secondary vehicle is removed from the primary vehicle, a data storage device for storing information regarding usage of the primary and secondary vehicles, a user interface device for displaying information regarding usage of the primary and secondary vehicles, and a user prompt for providing information regarding potential opportunities for use of the secondary vehicle to encourage usage of the secondary vehicle and lower CO2 emissions.