Ultraviolet LED Point-of-Use, Dose-Budgeted: Flow Against Dose, the Adenovirus Exception, Energy per Litre, and the Storage Problem UV Cannot Solve

SIMULATED, NOT MEASURED. A UV-LED tap unit is dose-budgeted: 55 mJ/cm2 at 1.0 L/min falling to 18.3 at 3.0 L/min, covering bacteria, typical viruses and Cryptosporidium but not adenovirus (160 mJ/cm2 required) at any practical flow; energy is 0.556 Wh/L and cost US$1.644 per 1000 L. UV leaves no residual, so protection ends at the tap. Nothing was built or field-tested.