On Dec 20, 6:14*pm, charles wrote:

I can remember an article in Eagle (1950s) about a Swiss trolley bus with
an enormous flywheel to use for motive power when there were no overhead
wires.

The Parry People Mover, a curious little railbus thing used on the
Stourbridge Town to Junction shuttle train, uses a flywheel. It's
charged up by a diesel engine (one that'd be too small to move the
vehicle effectively on its own) and by braking. Not a dissimilar
concept, just a different way of doing things (though of course with
its own challenges).

Neil