Solar Rooftop Calculator
Estimate solar panel system size for your roof. Enter available area, peak sun hours, and panel wattage to get system capacity, annual generation, electricity savings, and payback period.
โ๏ธ Solar Rooftop Calculator
System Size
Panels19 panels
System Capacity7.6 kW
Generation
Daily Output30.4 kWh/day
Annual Output11,096 kWh/year
COโ Saved9.1 tons/year
Financials
System Costโน418,000
Annual Savingsโน88,768
Payback Period4.7 years
Solar Rooftop System Sizing
A rooftop solar system converts sunlight into electricity using photovoltaic (PV) panels. Sizing depends on three factors: available roof area, peak sun hours in your location, and panel efficiency.
Quick Sizing Rules
| System Size | Roof Area Needed | Monthly Generation | Suitable For |
|---|---|---|---|
| 1 kW | 100 sq ft | 120โ150 kWh | 1โ2 BHK, low usage |
| 3 kW | 300 sq ft | 360โ450 kWh | 2โ3 BHK, moderate usage |
| 5 kW | 500 sq ft | 600โ750 kWh | 3โ4 BHK, AC usage |
| 10 kW | 1000 sq ft | 1200โ1500 kWh | Large house / commercial |
Government Subsidies (India 2025)
Under the PM Surya Ghar scheme: โน30,000/kW subsidy for up to 3 kW and โน18,000/kW for 3โ10 kW capacity. This can reduce system cost by 30โ40%.