What’s interesting is that you make perfect sense. But if you look, this shop was constructed brand new in the age of electricity. They certainly could have flooded it 24/7 with them fancy 'lectric lights. That giant gantry crane clearly has an electric motor. And while I don’t believe there was a steam plant anywhere on the grounds. I will have to go back and look at the layout. But I think this was an all electric facility. Built some time in the first decade of the 20th century.
My pic I guess was of the machine shop/ repair shop. But the round house is also wall to wall windows.