Originally Posted by
Pinelli
Bigger problem with hydrogen is making sure the car doesn't go bang if something goes wrong.
Brisbane City has just grounded half of its bus fleet (>500 buses) because an LNG tank exploded today. No one hurt luckily, it was just sitting in the depot, but it did damage two buses. Hydrogen is much worse.
They are working on developing 'sponges', made out of palladium and other materials that can store hydrogen quite densely, and yet safely in case of an accident.
Switzerland used to run a fleet of buses using flywheel technology. Plug them in overnight while a motor spun them up, unplug them for the day, and drive around, converting rotational kinetic energy to electric energy and back to kinetic again.
Again, big problem in an accident because if those flywheels let loose, they're storing an awfully large amount of energy in them and they can go flying.