A trolleybus (also called trackless trolley or trackless tram) is an electric bus that gets its power from the overhead wires.
Trolleybuses as most often used in the cities as means of public transport. Nevertheless, there are also suburban and even intercity trolleybus lines. The longest intercity trolleybus line is to be found on Krimea, Ukraine. It connects Simferopol with the seaside resort Yalta. This trolleybus line is 75 kilometers long.
Apart from the passenger trolleybuses, there are also freight trolleybuses, but they are less common.
Advantages and disadvantages
- Environmentally friendly (compared to bus)
- Electric motor needs less mantainment than diesel engine
- Trolleybus is ceaper than the tram
- Trolleybus is more flexible than tram, since it can move independently from its infrastructure (wires) using batteries
- Trolleybuses are more expensive than buses
- Trolleybus wires cause visual pollution
- Average trolleybus can carry less passenger than tram (approx. 100 vs 200, if articulated)
While only few American and West European cities have trolleybuses, trolleybuses are very popular in Eastern Europe and former Soviet Union.
There are three French cities, Nancy, Caen and Clermont-Ferrand, that have so-called "rubber-tired trams". The vehicles got their power from the overhead wires and look like modern articulated trams, but they actually run on rubber-tired wheels, like trolleybuses. The only rail is used to guide to vehicle, but vehicle doesn't run on the rail, like normal trams do. Therefore the name "tramway" is controversial, and the vehicles are rather something between tram and trolleybus.