A Village Chlorination System with No Chemical Supply Chain: Electrolytic Hypochlorite from Salt, Water and Sunlight, Sized End-to-End from Electrochemistry and Chlorine Decay

A complete, closed first-principles sizing of a village chlorination system that needs no chlorine supply chain: a photovoltaic array powers a brine electrolyser producing sodium hypochlorite from salt and water, stored under a stated decay law and dosed against a stated chlorine demand and distribution residual decay. For a 10 m3/day supply the required tank dose is 1.185 mg/L, decay-corrected production is 13.65 g of chlorine per day at 4.652 kWh/kg, requiring 63.5 Wh/day (14.1 Wp in theory, a 50 Wp module in practice) and 45.0 g of salt per day; hypochlorite storage decay at 30 C forces a production oversize factor of 1.152. All results are simulated, not measured; nothing described has been built or tested. Computations are reproducible from the deposited compute.py and results.json.