Comparison table
| Item | 3 kW | 5 kW |
|---|---|---|
| Suits monthly use of | 250–400 units | 520–700 units |
| Annual generation | ~4,377 units | ~7,295 units |
| Daily average | ~12 units | ~20 units |
| Panels (545 W) | 6 | 10 |
| Roof area | ~270 sq ft | ~450 sq ft |
| Typical price before subsidy | ₹1.74 lakh – ₹2.04 lakh | ₹2.9 lakh – ₹3.4 lakh |
| PM Surya Ghar subsidy | ₹78,000 | ₹78,000 |
| Estimated monthly savings | ~₹2,736 | ~₹4,559 |
| Payback (if fully used) | ~3.3 years | ~4.2 years |
| Subsidised loan (≤3 kW) | Eligible | Standard solar loan |
Prices are indicative for DCR modules and a standard structure; elevated structures cost more.
Choose 3 kW if…
- Your average bill is roughly ₹2,000–₹3,500 a month.
- Roof space is limited.
- You want the collateral-free, low-interest PM Surya Ghar loan (up to 3 kW).
Choose 5 kW if…
- You run two or three ACs through summer.
- You plan to add an EV or a home office soon.
- You have 450+ sq ft of shadow-free roof and a suitable sanctioned load.
The mistake to avoid
Buying 5 kW for a home that only uses 300 units. Under net metering, the surplus beyond your consumption earns far less than the units you replace, so the extra 2 kW barely pays back. Size to your real consumption — our calculator does this from your bill.