https://www.lowcarbonhub.org/p/projects/sandford-hydro/ says that the hydro generates 1.6GWh every year and runs at 440kW. 1.6 x 10^9 divided by 365.25 divided by 24 = 182kW. This must be the average power with 440kW the peak, I suppose. 1.6 x 10^9 divided by 450 = 3500kWh roughly or a household electricity bill of around £400 a year.
