A 3kW system may suit a smaller home with modest electricity use, while 5–6.6kW systems are common for households using more power during the day. A 10kW system can be worth considering for larger homes, electric vehicles, pool pumps or high daytime demand, subject to roof space and network limits. Actual generation depends on your location, panel direction, shading and equipment, so compare estimated annual output rather than panel count alone. A qualified installer can assess your usage, export limits and battery plans before recommending a size.