Off-grid system for a livestock unit, Ziabar

The brief

A livestock unit far enough from the grid that running a line would have cost more than the array. The main loads were a water pump and ventilation fans, both with high starting currents that had to be designed into the inverter selection.

How it was done

1. 01 Daily load and pump starting current calculated to size the inverter
2. 02 Battery bank designed to carry consecutive overcast days
3. 03 Loads prioritised: ventilation and pumping first, non-essential lighting sheddable
4. 04 Galvanised ground-mount structure, standing off the ground to drain and breathe
5. 05 DC protection with a fuse and isolator per string
6. 06 Operator training: reading battery state and managing the load

The outcome

The unit runs with no grid connection, and pumping and ventilation have held up across the year. The operator reads the battery state and knows which load to drop during a run of overcast days.