There's a hydroelectric powerhouse near hear that was built in 1912 and remained in use until the late 1990's. Then a new powerhouse with more efficient turbines came online, and the old powerhouse was turned into a museum. All the original switchgear still seems to be there, though it was adapted for remote monitoring and control at some point.
There are a few photos here:
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It was built in a time when there was no power grid in the area, so it was designed to be able to start "cold", with no outside source of electricity. A bank of lead-acid batteries provided initial power, probably for instruments and DC generator field. There are a pair of DC generators, driven by tiny turbines, to provide DC armature power to the main alternators. Output voltage control seems to have been done with
*large* carbon rheostats in the DC supply to each alternator.
The washrooms look like they are 1912 vintage, too...
Dave