The right solar system size in 2026 depends on your electricity use, roof space, budget, daytime energy demand and whether you plan to add a battery or electric vehicle. A system with around 6.6 kW of panels and a 5 kW inverter is common, but larger systems may suit homes with high usage, subject to local network export limits. Review your recent electricity bills and have an accredited installer model your generation and export options. The installer and your electricity distributor can confirm what system size and connection requirements apply to your property.