Two poles on the roof of your bus just isn’t cutting it anymore?
What you need is this:
What you are looking at is a gyrobus. Developed in Switzerland, it uses the energy stored in a large flywheel to drive the bus (via an electric motor/generator) some distance before stopping at “charging stations” along the route to speed up the flywheel again. It was said to be capable of distances of around 3-6km between charges in traffic and braking energy was captured and used to help the (over one tonne) flywheel spin a little longer.
Three systems were constructed in Switzerland, Belgium and, weirdly, the Congo and surprisingly none survive to this day. The last surviving gyrobus in the world is preserved at the transport museum in Antwerp.
Touted as the “future of transport” ( back in the time when every such crackpot scheme was touted as such) this incarnation of the technology had major flaws; the buses were very heavy, rode badly and the system actually used more power than a conventional bus or tram at the time. A dead end then? Well no, not quite. Development of the idea continues to this day and there are some systems very similar in concept in use in motor racing (KERS anyone?) and has broken surface in some hybrid drivelines for commercial vehicles. GKN had a low cost hybrid system using this same technology ready for production and was actually trialled in some buses until the plug was pulled suddenly a few years back.
So flywheel powered public transport is dead? Nope. If you take yourself to Stourbridge in the West Midlands, you can see it in action in the form of the class 139 that shuttles between the town and junction stations. Will it make a further comeback? Who knows but I wouldn’t count it as a total dead end just yet.