An electric trolley bus gets its power from electrical wires suspended above city streets. The bus is connected to the cables by a pair of contacts mounted on top of the bus.
Double-decker buses are a popular form of public transportation in London, where parking can be extremely difficult. The advantages of using buses within a city include the low cost, the relative freedom from stress in driving and parking a car, and, in this case, the view. Efforts to conserve energy and reduce traffic and pollution have encouraged more people to use buses and more cities to extend the scope of their bus systems.
Bus service operates diesel or electric buses along defined routes and according to published schedules. Buses vary in size from minibuses, which can carry up to 20 passengers, up to multisection articulated buses, which have an extra passenger unit attached by means of a flexible joint. Articulated buses can carry as many as 130 passengers. Buses operate on both city streets and highways. Some streets and highways have special lanes reserved only for bus transit, thus increasing the speed and efficiency of bus travel. Trolley buses are electrically powered buses that use electricity from overhead wires mounted along city streets. The use of electric power reduces pollution, noise, and the need for refueling but also limits the routes a trolley bus can take.