Given most of water comes from public facilities it is structurally just unsanctioned and ineffective transmission of power from shared pump to private generator. Would be a simple energy theft if you didnt pay for water. A waste of water and energy anyway.
Tldr? Why would anyone do this? To what end?
You can do this with a long enough hose and height difference by just using river water
Why not set something up by the river instead and just route the power?
what? Something like a Water Mill? You are crazy!
To utilize power that is otherwise wasted? The water can still be used in the garden etc. Also if there is a power cut the water often keeps running, so you could use this to charge a small battery or a phone.
If the power goes out you’d probably be better off using solar or a even gas. Maybe if you’re using water for something else anyways it makes sense but how much power can really be generated by turning a house on for a min? How much water is wasted?





