When we talk about means of transport, there are many of them, some common and others very interesting, such as the trolleybus . Also known by the name of trolley or trolley , this means of transport is a type of bus that works with electricity and is powered by means of laying cables above from which the electricity necessary for its movement is obtained.


Information of interest

  • Vehicle Type:  Electric Road Vehicle
  • Year:  1882
  • Inventor: Ernst Werner von Siemens
  • Main uses:  Transport of people

What is a trolleybus?


Trolleybus is a means of transport using electric power cables suspended above the transport and also uses tires of rubber for proper movement and transport of people.

  • Definition
  • What is a trolleybus for
  • Characteristics
  • Story
  • Trolley parts
  • How a trolley bus works
  • Crew
  • Advantage
  • Disadvantages
  • Examples
  • Curiosities


Trolleybus, also known as the trolley trackless , is a vehicle that is operated in the streets with tires of rubber and is powered by electricity which is extracted two overhead cables by trolley poles. It is different from a tram , which runs on rails rather than tires and is therefore a form of tram.

What is a trolleybus for

The trolleybus was designed with the aim of functioning as a means of transport for distances that are not excessively long from one place to another.


The trolleybus is characterized by being an electric bus that is powered by a system very similar to that used by trams . It is a more flexible means of transport , since it circulates on the road using tires instead of using special routes. They are non-autonomous electric buses, as they do not have electricity stored on board, so they must be powered from an external source of energy . It is a mix of tram and bus and provides intermediate transportation capacity between buses and trams, less capacity than a tram but more than a bus. 


In the late 1880s, several small transit systems were put into operation using electrical power supplied by the Leo Daft system in the United States , which used two overhead cables; the electrical energy was collected by a small carriage , or trolley , that ran on the cables . The car was carried in the vehicle by a bent piece called an arch or by a folding and adjustable frame called a pantograph . The word car comes from the small trolley of the Daft system. The trolleybuses had the advantages of electric propulsion which is a quieter operation, which avoids the production of smoke from and also has a faster acceleration and could load passengers on the sidewalk.

Several tram installations were made in England , especially in London and in the United States, but they were quickly replaced by buses . Trolleybuses were widely adopted by state-run urban transport systems in the Soviet Union , and operated alone or in conjunction with the subway , trams, or buses . Other Eastern European countries adopted them, as did China , Switzerland, and Italy . At the end of the 20th century, trolleybuses were still an important form of public transport in many Russian cities, but the trend in most other countries was to replace them with buses.

Trolley parts

The trolleybus consists of the following parts :

  • Lying
  • Sign travel
  • Mirror outside rearview
  • Lantern
  • Front and rear doors
  • First front single axle and second rear dual axle
  • Decorative bars
  • Turnbuckles , rope , head and trolleys or booms
  • Trolley or Boom Hitch
  • Trolley base and machine number
  • Lines trolleybus
  • Drivers

How a trolley bus works

The trolleys press the string to make contact . In the place where the plume makes contact with the line, a coal is placed for the flow of energy . The energy passes through a bank of resistors to dissipate the heat, avoiding heating in the event of a voltage variation. The energy goes through a converter , which converts it from 600 to 640 Volts of 12 volt direct current which is used for trolley accessories, such as the dashboard , internal lighting , etc.

The brake and the steering work through a compressed air system and the energy that comes directly from the electricity company . The company is in charge of feeding a substation with alternating current , reduced by a transformer , to go to a rectifier that converts it into direct current.

The electrical system has various electrical connections and to differentiate them, the cables generally have different colors , thereby codifying a kind of electrical language to operate the system.


The crew of a trolley bus is basically its driver or chauffeur . In some countries they usually take a companion who is in charge of explaining to passengers the different places where they pass.


Some advantages that are obtained with the use of the trolley bus are:

  • By its method of electrical operation , this transport produces less pollution air and noise. It is the quietest and cleanest .
  • It has been designed for the comfort of the passengers who use it, and for the comfort of the transport itself.
  • It generates a pleasant , spacious , comfortable trip with greater intimacy among passengers.
  • They can generate electrical energy from kinetic energy .
  • They have a better grip than trams.


One of the main disadvantages that can be observed in the use of the trolleybus is that when it is separated from the catenary , the vehicle will stop. For this reason, a battery or a heat engine must be included to avoid the inconvenience. Tires also produce increased spending of electricity and occurs if a blackout of electricity , trolleybus can not then function.


We can find trolleybuses in the following cities: Mendoza in Argentina , Lima in Peru , Medellín in Colombia , Caracas in Venezuela , Santiago in Chile , Port of Spain , Trinidad and Tobago .


One of the most curious aspects of the trolleybus is that the longest line to be transported by this means has a length of just 86 kilometers and is located in Russia . In addition, the oldest fleet of these means of transport is located in the city of Valparaíso in Chile . Currently they can be found in about 315 cities around the world and in some cities this type of transport is not known.

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