You get about 6 hours of direct sunlight on the panels so his sizing is probably about right? My dad gets about 6 kWh daily during the summer from an 1140 Wp P

You get about 6 hours of direct sunlight on the panels so his sizing is probably about right? My dad gets about 6 kWh daily during the summer from an 1140 Wp PV array. 45° latitude, 1250 W/m² yearly insolation.