How to use this data — Peak sun hours tell you how much solar energy reaches your location each day. To estimate the system size you need, divide your daily kWh usage by the peak sun hours for your region: system size (kW) = daily kWh ÷ peak sun hours. Your monthly electricity bill shows your total kWh for the month — divide that by the number of days to get your daily figure. For example, if your bill shows 900 kWh/month, that's about 30 kWh/day. In a region with 5.5 peak sun hours, you'd need roughly a 30 ÷ 5.5 ≈ 5.5 kW system.