Yeah, I came here to say this. In particular, I remember a bit about how to take an alternator from a car, use a river's current and a paddle-wheel to spin it,

Yeah, I came here to say this. In particular, I remember a bit about how to take an alternator from a car, use a river's current and a paddle-wheel to spin it, and tada: you've made a hydro-electric generator. Each one provides a small but consistent amount of electricity, so if you need more power, find another alternator.