Why The Trolleybus?
With a much smaller emphasis on cars, a city needs to
be based around its public transportation. But which mode?
Subway, Elevated Rail and Monorail
Subways, elevated rail and monorail are grade separated – they run
along tracks completely separate from pedestrians and street traffic.
As well as being safer, this also means they can travel faster.
They can also be automated, doing away with the need for
However, these are also the most expensive modes to install.
Elevated rail and monorail are somewhat cheaper, but some people object
to them on visual grounds, particularly elevated rail and the huge areas of shadow
Diesel buses are the cheapest option. They are also the most
However they are roughly as loud and smelly as the fifty or so cars
they replace. And with their lurching ride and vibrations from the
diesel engine, they aren't comfortable to ride either.
Hybrid buses promise slight improvements, but they will still be the
least likely to tempt people out of their cars.
Trams and Trolleybuses
Trams and trolleybuses are altogether better propositions.
Taking their power from overhead lines, they emit no pollutants into the
street. They are energy efficient, especially when equipped with regenerative brakes,
which recover energy that would otherwise be lost when braking and feed it back
into the overhead lines.
They offer smooth, quiet rides. And, so long as the
trolleybuses are fitted with kerb guidance for level boarding at stops,
both are accessible to everyone.
They're also inexpensive enough to stay within the budget of small to
So tram or trolleybus?
The biggest advantage trams have over trolleybuses is their
greater capacity, particularly when trained together, so each driver can transport more passengers and thus fewer
are needed, reducing operating costs. In practice, however, very long trams
don’t mix well with pedestrian areas. For example the Nottingham trams are 33m
long, compared to 25m for a double articulated bus.
Trolleybuses are cheaper than trams. Since they operate on
rubber tyres, they are quieter. They’re safer too, able to brake much more
quickly in an emergency and steer around stray pedestrians.
In any public transportation system, reliability is very
important. When an entire city depends upon that system, reliability is
absolutely crucial. And it is here where the trolleybus really scores over the
tram. If equipped with an auxiliary battery, the bus is free to leave the
overhead lines to circumvent obstacles, whether they be broken-down vehicles or
road works. Trams just can’t do this, and any such problems would have a large
impact on service.
With medium sized cities the higher capacity of trams makes
them more or less essential, but the best choice for small cities is the