3kW solar system in India: cost, output, savings and who it suits
The 3 kW solar system is the most popular choice for Indian residential rooftop solar in 2026. It is the size at which the PM Surya Ghar central subsidy is maximised at Rs 78,000, and it suits the consumption profile of the majority of urban Indian households with 2 to 4 BHK homes.
What does a 3kW solar system cost in India?
A fully installed 3 kW rooftop solar system in India currently costs Rs 1.5 lakh to Rs 2 lakh before subsidy. The range reflects differences in panel brand, inverter quality, installer location, and roof complexity.
After the PM Surya Ghar central subsidy of Rs 78,000, the out-of-pocket cost falls to approximately Rs 72,000 to Rs 1.22 lakh.
If your state has an active additional state subsidy through GEDA, HAREDA, RRECL, or similar agencies, the net cost reduces further.
The subsidy is paid as a direct bank transfer 30 to 60 days after your commissioning certificate is uploaded to the portal. You pay full installation cost upfront.
How much electricity does a 3kW system generate?
A 3 kW system generates different amounts depending on your location and the solar irradiance your area receives.
| City | Monthly generation (approx) | Annual generation (approx) |
|---|---|---|
| Jaipur, Jodhpur | 420 to 480 units | 5,000 to 5,800 units |
| Ahmedabad, Surat | 400 to 460 units | 4,800 to 5,500 units |
| Delhi, Gurugram | 360 to 430 units | 4,300 to 5,100 units |
| Hyderabad, Nagpur | 350 to 420 units | 4,200 to 5,000 units |
| Pune, Bengaluru | 330 to 390 units | 4,000 to 4,700 units |
| Chennai, Mumbai | 300 to 370 units | 3,600 to 4,400 units |
These figures assume optimally tilted, south-facing panels with no significant shading. East or west-facing panels generate 10 to 20 percent less.
Who does a 3kW system suit?
A 3 kW system is well-matched to a household consuming 250 to 450 units of electricity per month.
This typically describes a home with: 1 to 2 air conditioners used moderately, a refrigerator, washing machine, LED lighting throughout, a television and entertainment system, and standard kitchen appliances.
If you consume below 200 units per month, a 2 kW system may suit you better. If you consume above 500 units consistently, consider 4 to 5 kW.
However, many households choose 3 kW specifically because it maximises the central subsidy even if a 2 kW system would meet their current consumption. This can make sense if your consumption is likely to grow — adding an EV charger, additional AC, or a heat pump will increase consumption over time.
How much will a 3kW system save on your bill?
Monthly savings depend on your tariff and consumption pattern.
| Scenario | Monthly saving |
|---|---|
| 300 units/month, mid tariff | Rs 1,800 to Rs 2,500 |
| 400 units/month, mid tariff | Rs 2,500 to Rs 3,200 |
| 500 units/month, higher tariff | Rs 3,000 to Rs 4,000 |
After the subsidy, with out-of-pocket cost of Rs 90,000, and savings of Rs 2,500 per month, payback is 36 months — 3 years. After that, approximately 22 years of free electricity generation.
What does a 3kW system physically look like?
A 3 kW system using standard 400-watt panels requires 7 to 8 panels. Each panel is approximately 1.7 metres by 1 metre.
For 8 panels mounted at an angle, you need approximately 25 to 35 square metres of usable roof space. This is typically available on a 2BHK or larger Indian flat or independent house rooftop.
The inverter is a box roughly the size of a briefcase, mounted on an exterior wall near your main distribution board. It makes a low hum during operation and is silent at night.
What warranties come with a 3kW system?
Quality systems come with three warranty types.
Panel performance warranty: Most Tier 1 panels carry a 25-year linear performance warranty guaranteeing at least 80 to 82 percent of rated output at year 25.
Panel product warranty: 10 to 12 years on panel manufacturing defects, from reputed brands.
Inverter warranty: Typically 5 years standard, extendable to 10 years with some brands. The inverter is the component most likely to need replacement within the system’s life.
Installation warranty: Reputable installers offer 1 to 5 years on workmanship.
Summing up
The 3 kW system is the right size for most urban Indian households and the smart financial choice because it maximises the PM Surya Ghar central subsidy. At Rs 72,000 to Rs 1.22 lakh out of pocket after subsidy, with monthly savings of Rs 2,000 to Rs 3,500 for a typical household, it pays back in 3 to 5 years and generates free electricity for 20 or more years after that.