Solar + Electric Car · Example: Tata Punch EV
Drive your EV on your own rooftop solar
Sunshine is the fuel. At 6 km per unit, 5 kW of solar is enough for about 3,510 km of driving a month if all of it went to the car. A typical owner driving 1,500 km a month uses about 250 units, 43% of this plant’s output.
| Solar system | 3 kW | 5 kW | 7 kW |
|---|---|---|---|
| Monthly generation | 351 units | 585 units | 819 units |
| EV driving per month* | 2,106 km | 3,510 km | 4,914 km |
| Full charges / month (30 · 40 kWh) | 10.6 · 8.0 | 17.7 · 13.3 | 24.8 · 18.6 |
| Investment after subsidy | ₹1,22,000 | ₹2,37,000 | ₹3,62,000 |
| Annual electricity value | ₹29,484 | ₹49,140 | ₹68,796 |
| Payback period | 4.1 years | 4.8 years | 5.3 years |
| Annual return | 24.2% | 20.7% | 19.0% |
5 kW is the ideal start for a home with one EV: solar power for the house and the car. With a hybrid system you can also charge at night from the battery.
* Theoretical figure if all solar power goes to the EV. Assumes 3.9 units/kW/day (Kerala average), ₹7/unit, 6 km per metered unit, 10% charging loss, petrol ₹107/litre at 15 km/l. An on-grid system cannot charge the car directly at night; net-metering rules apply. Confirm variant, range and price with the vehicle maker. Not a guaranteed return.


