Solar Water Disinfection Sized for a School: A Dose-Based Bottle, Area, Storage and Cost Bound

SIMULATED, NOT MEASURED. A dose-based sizing bound for solar water disinfection (SODIS) for a school: UV-A dose requirements for 3-log virus and bacterial targets, PET bottle transmission, turbidity attenuation and cloudy-day derating determine how many bottles, what rack area and what storage buffer a school of 300 pupils at 1.0 L per child per day requires, and the price per litre delivered (US$0.00744/L at 91.0% modelled coverage). The failure envelope for turbid water, aged bottles, cloudy and rainy days and 4-log virus requirements is stated in full. Nothing was built and no water was used by children.