Fun fact:
There are electric dump trucks which never need external charging - they go uphill empty, fill up, then use regenerative braking hauling cargo downhill, getting enough energy to repeat.
Very narrow use case, yes, but interesting/amusing.
Might work if you have say a copper mine at a mountaintop. There is a big one in Indonesia but not many others.
they go uphill empty, fill up,
= = =
And at the top, the (no-longer-steam) shovels are running on batteries, too?
Kind of like pumping river water up hill to store it during excess power times of the day.