Off-grid Solar Sizing Calculator

Project

Project name Prepared for Start from an example

Loads

For appliances that cycle (fridges, pumps), enter the hours the compressor or motor actually runs per day. Surge is the start-up multiple (fridge or pump compressors are often 3-7x).

Appliance	Watts	Qty	Hours/day	Surge x	DC?	Wh/day	Remove

Site and equipment assumptions

Peak sun hours (worst month) Days of autonomy Battery chemistry Depth of discharge Battery round-trip efficiency Battery unit (V) Battery unit (Ah) Panel rating (W) System derate (PV losses) Inverter efficiency Share of AC loads on at once System voltage Battery to inverter cable (m, one way) Controller to battery cable (m, one way) Max voltage drop (%)