Quote:
Originally Posted by Piwoslaw
True. I forgot about the batteries.
And it's a shame that trains don't have a means to store braking energy. Of course, I mean commuter trains and such, not long distance freight trains.
|
Some do I think. Leyland (the bus and truck people, not the clunky cars built by unionised militant workers) used a few different systems to generate energy from braking on buses, and later on their (unsuccessful) bus to train conversions.
One of them definitely used a compressed air reservoir of some kind. The pressure would be built up under braking then released to give the bus a 'push' when it started up to save fuel. Another system used a flywheel which would be spun up under braking and then used to power an electrical 'assist' on restart.
A similar system was developed by a german tuner in the early 80s to try and remove turbo lag at the time when turbos did nothing below 4000 rpm. The system bled some pressure from the wastegate into a chamber and then released it when the pedal was floored at lower engine speed. It would be enough to get the engine to the point where the turbo could take over. It didn't work in the real world of course, and they went on to use autoboxes to 'keep the engine spinning fast enough for the turbo'. Kind of like developing a super efficient hair dryer by inventing dry water.