About the Solar Panel Output Calculator
What is the Solar Panel Output Calculator?
This solar panel output calculator estimates how many units a rooftop system will generate. It multiplies the system size by your location's peak sun hours and deducts losses from heat, dust, wiring and the inverter.
In most of India, each kilowatt of panels generates about 4–5 units a day, or 1,400–1,700 units a year.
How to use the Solar Panel Output Calculator
- Panel Rating (Wp) (sample: 540)
- Number of Panels (sample: 6)
- Peak Sun Hours per Day (sample: 5)
- System Losses (%) (sample: 20)
- Electricity Tariff Saved (₹ per kWh) (sample: 7)
- Press Estimate Solar Output (results also refresh as you type). The result card shows the Energy per Day, along with System size, Energy per month, Energy per year and Yearly savings.
Formula used
Daily energy (kWh) = System kWp × Peak sun hours × (1 − Losses)
- System kWp = panel watts × number of panels ÷ 1,000
- Capacity utilisation factor = daily kWh ÷ (kWp × 24)
Output is lower in the monsoon and higher in March–May.
Worked example
These are the sample values already filled in the calculator above, and the result it returns for them:
| Input | Sample value |
|---|---|
| Panel Rating (Wp) | 540 |
| Number of Panels | 6 |
| Peak Sun Hours per Day | 5 |
| System Losses (%) | 20 |
| Electricity Tariff Saved (₹ per kWh) | 7 |
| Result | Value |
|---|---|
| Energy per Day | 12.96 kWh |
| System size | 3.24 kWp |
| Energy per month | 389 kWh |
| Energy per year | 4,730 kWh |
| Yearly savings | ₹33,113 |
| Capacity utilisation factor | 16.7% |
Tips for using the Solar Panel Output Calculator
- Face panels south, tilted roughly at your latitude, and keep them shade-free.
- Clean panels every 2–4 weeks; dust can cut output by 5–15%.
- PM Surya Ghar Muft Bijli Yojana offers subsidies for residential rooftop solar.