Abstract
Road vehicles are more energyconsuming than rail vehicles. In spite of a certain incomparability of traffic modes it is clear, that energy can be saved if transport by private car is substituted by transport by bus or by train. The trolleybus combines the advantages of bus and tram, having few of the disadvantages. The advanced transport modes can only be used in densely built-on centres, because of high costs. Saving of energy does not yet play a great part in the choice of transportation modes.