Sunwon Solar › Solar unit calculator
Solar unit calculator for your home
Our in-house estimator for Pondicherry and Tamil Nadu homes. The numbers below are a guide; the exact ones are in your free written quote.
How many units a solar panel makes in Pondicherry
A 1 kW rooftop solar system in Pondicherry and Tamil Nadu makes about 4 units a day on a clear day, which is roughly 125 units a month and 1,500 units a year over the year, counting cloudy and rainy days.
| System size | Per day (clear) | Per month | Per year | Roof needed |
|---|---|---|---|---|
| 1 kW | ~4 units | ~125 units | ~1,500 units | ~100 sq ft |
| 3 kW | ~12 units | ~375 units | ~4,500 units | ~300 sq ft |
| 4 kW | ~16 units | ~500 units | ~6,000 units | ~400 sq ft |
| 5 kW | ~20 units | ~625 units | ~7,500 units | ~500 sq ft |
Make sure the roof is shade-free between about 9 am and 4 pm; even a small shadow on one corner can cut what a whole string makes.
Suggested system size by EB bill
| Monthly EB bill (Puducherry) | Bi-monthly EB bill (Tamil Nadu) | About units | Suggested kW | Price (incl. GST) | After central subsidy |
|---|---|---|---|---|---|
| Up to ₹3,000 | Up to ₹5,000 | up to ~300/mo | 3 kW | ₹1,89,000 | ₹1,11,000 |
| ₹3,000 – ₹5,000 | ₹5,000 – ₹8,500 | ~500/mo | 3 kW | ₹1,89,000 | ₹1,11,000 |
| Above ₹5,000 | Above ₹8,500 | 500+/mo | 4–5 kW | ₹2,42,000 – ₹2,95,000 | ₹1,64,000 – ₹2,17,000 |
In Tamil Nadu, eligible homes also get up to ₹22,000 state top-up for 3 kW and above, so the net price comes down further.
Try the full calculator
Our home-page calculator does the same working with your real bill: suggested kW, subsidy, estimated EMI and payback.
Estimates — what we assume
- Generation: about 125 units per kW per month in this region, averaged across the year.
- Roof: about 100 sq ft of shade-free roof per kW; RCC terraces and sheet roofs both work.
- Tariff: today's domestic tariff of your state (Puducherry monthly, Tamil Nadu bi-monthly); fixed charges are not included.
- EMI: illustration only — a 90% loan over 10 years at about 5.75% a year for loans up to ₹2 lakh; the lender decides your real rate, tenure and approval.
- Payback: an estimate that depends on your actual usage, tariff, system cost, subsidy, financing and generation.
Questions people ask
How many solar units does a 3 kW system make a day in Pondicherry?
About 12 units on a clear day, or roughly 4,500 units a year averaged across the year. Cloudy and rainy days make less, sunny days make more.
Which kW system is right for a 2 BHK home?
Most 2 BHK homes with 1–2 ACs run on a 2–3 kW system. A bill around ₹2,500 a month in Puducherry usually suits 3 kW. See our size table above.
Does the solar unit calculator include subsidy?
Yes. The home-page savings calculator shows the central PM Surya Ghar subsidy and the Tamil Nadu state top-up where it applies, and shows what you pay after subsidy.
Can I size my system from only my EB bill?
Yes, that's enough for a first estimate. For the exact system size we also check your roof during the free visit, because shade, direction and the EB connection all matter.
Talk to a person, not a call centre.
Send a photo of your EB bill on WhatsApp and we reply with the right system size, your subsidy and your EMI. We reply within 5 minutes, 8 am – 8 pm, every day.