They put buses (battery and diesel) inside garages overnight. That helps the battery buses in keeping them powered up, though generally they do plug them in.
Streetcars, light rail, and heavy rail (subway) are mostly stored outside, though they can be powered up overnight to keep warm. If they need cleaning or maintenance, they put them inside.
Actually, they shift streetcars all night long. Practically every car is moved inside (which is where the interior cleaning is done) and then spotted back outside in the order that’s planned for next day’s dispatch. (Ask me how I know - I lived a block north of Roncy for five years. Lots of screeching and some pretty nasty bang’s.) So each car potentially makes two moves a night, one into the barn and one out again.
I’m curious how that works with buses. Are they currently refuelled and spotted for cleaning when they come in? Or are they shuffled for service all night long? Is that done by the operator returning the bus, or by maintenance? (Does the operator unplug in the morning, or is it ready to go? ) If they are shuffled,, they may be plugged in and then unplugged twice each night. I presume that there is an interlock that prevents the bus from being moved while connected to the charger, or human error will happen eventually. But is the hardware going to add time to the hostler’s task? Sounds simple, just unplug or lower trolley arm before you move vehicle, but if that’s even 15 seconds it will add up when one moves 30 or 40 a night....and has to reconnect them after cleaning to finish the charging cycle. Not a dealbreaker, but just one complication. Perhaps quicker than time spent at the fuel pump, of course. Am I missing something?