Design solar water systems against the standard.

Free calculators that implement the UNICEF and Water Mission design guide. Every result shows its calculation trace and the design rules it was checked against.

Water demand

Daily project water demand from population, usage and losses. Computes all three demands the guide requires and checks the design basis against each.

Total dynamic head

Static lift from the dynamic water level, pipe friction by Hazen-Williams, minor losses. Flags survey-grade elevation and velocity constraints.

Solar array sizer

Panel field performance at your site conditions, array output with derating, motor voltage-window checks, and the IEC 62253 four-condition report.

Where the rules come from

Each check cites a numbered rule extracted from the guide, section by section. The calculation engines reproduce the guide's own worked examples exactly before any release. Where the guide is silent, the source used is named instead; nothing is invented.