A hydroelectric dam would be really cool to see! It could provide electricity to a broad area. If put into the game it should be difficult to get operational. Missing parts you have to find, broken parts you have to replace, and of course repairing transformers and what not. Very interesting idea that could bring a really interesting dynamic to the game.
It would need to be fortify-able in some way to keep zombies out, or at least make it difficult for them to break in. Aside from the rushing water sounds, the generators and other machinery make noise that would potentially attract zombies. You wouldn't want them getting in and break things at random! I suppose players could sabotage it as well.
There's a main coal burning power plant on the island, this plant will be functional in probably even the earlier builds of STN. The plan is to let the plant power substations. The substations could power even smaller stations outside towns. Fix all the breaker panels and electric meters and in theory you could power an entire town.
With alpha release you'll likely only be able to power individual structures. With either a small portable generator (found around the map) or for larger structures a commercial grade, fixed (typically on the rooftop) generator.
Electrics will play a big role in the game, we'll tweak them and get all your feedback and ideas after release
No, totally forgot about coal mines actually lol. We could maybe get one in someplace, we could also assume the coal maybe was barged to the island.
We all really want to eventually introduce a working freight train. A train that would run from the port to the power plant. The idea being you'll need to team up to get the train running, get the train full of coal to the power plant.