Off-grid solar needs more than panels: you will generally need batteries, an inverter, backup generation and enough capacity for periods of low sunlight. System sizing depends on your household’s energy use, location, seasonal conditions and whether high-demand appliances such as air-conditioning or electric hot water are included. A properly designed system should allow for battery replacement, maintenance and a backup plan during extended cloudy weather. Ask an accredited solar designer or electrician to assess the property, and check any planning, electrical and building requirements with your state authority or local council.