How Many Units Does 1kW, 3kW, 5kW & 10kW Solar Generate Daily in India? Real Data
Rajesh Sharma · September 21, 2026 · 7 min read
📊 Benchmark Rule: In India, 1 kW of rooftop solar panels generates an average of 4 kWh (units) per day over a full calendar year. However, actual daily output varies between 3 units on overcast winter days to 5.5 units during peak clear summer days.
1. Standard Daily & Annual Generation Table
| Solar Capacity | Daily Avg Output (Units) | Monthly Avg Output (Units) | Annual Output (Units) | Est. Annual Bill Savings (at ₹8/unit) |
|---|---|---|---|---|
| 1 kW System | 4.0 – 4.5 Units | 120 – 135 Units | 1,440 – 1,550 Units | ₹11,500 – ₹12,400 |
| 3 kW System | 12.0 – 14.0 Units | 360 – 420 Units | 4,300 – 4,800 Units | ₹34,400 – ₹38,400 |
| 5 kW System | 20.0 – 23.0 Units | 600 – 690 Units | 7,200 – 8,000 Units | ₹57,600 – ₹64,000 |
| 10 kW System | 40.0 – 46.0 Units | 1,200 – 1,380 Units | 14,400 – 16,000 Units | ₹1,15,000 – ₹1,28,000 |
2. Seasonal Generation Variation (Summer vs Monsoon vs Winter)
- Summer (March – June): Peak irradiance. A 3kW system generates 14 – 16 units/day. (Note: Extreme heat over 45°C causes a minor 5% drop due to thermal coefficient).
- Monsoon (July – September): Rain & clouds. A 3kW system generates 6 – 9 units/day on overcast days, spiking to 13 units on clear post-rain days.
- Winter (October – February): Shorter sun hours but cooler panel temperatures. A 3kW system yields 11 – 13 units/day.
3. Top 3 Factors Influencing Your Daily Generation
- Tilt Angle & Azimuth: Facing south at an angle equal to your city's latitude (e.g., 28° in Delhi, 19° in Mumbai) maximizes annual generation by up to 12%.
- Shading Loss: Even a partial shadow from a water tank or parapet wall on 1 panel can drop string inverter output by 25% to 50%.
- Panel Technology: N-Type TOPCon panels generate 5% to 8% more daily units than legacy Polycrystalline panels.