Solar Panel vs Electricity Bill — How Much Will You Actually Save?
The most important question before going solar is: how long until I get my money back? Let's do the math with real Indian electricity tariffs.
How Electricity Tariffs Work in India
Indian electricity uses a slab system — the more you use, the higher the rate per unit:
| Monthly Units | Typical Tariff (₹/unit) | Monthly Bill |
|---|---|---|
| 0–100 units | ₹3–5 | ₹300–500 |
| 101–300 units | ₹6–8 | ₹900–2,400 |
| 301–500 units | ₹8–12 | ₹2,400–6,000 |
| 500+ units | ₹10–15 | ₹5,000–15,000 |
Higher tariff slabs = better ROI for solar
Savings by Monthly Bill Amount
| Current Bill | Ideal System | Net Cost (Post-Subsidy) | New Monthly Bill | Payback Period |
|---|---|---|---|---|
| ₹1,000 | 1 kW | ₹35,000 | ₹50–150 | 3–4 years |
| ₹2,000 | 2 kW | ₹60,000 | ₹100–300 | 2.5–3 years |
| ₹3,000 | 3 kW | ₹92,000 | ₹200–500 | 2.5–3 years |
| ₹5,000 | 5 kW | ₹2,00,000 | ₹300–700 | 3–4 years |
| ₹10,000 | 10 kW | ₹4,22,000 | ₹500–1,500 | 3–4 years |
City-wise Savings Comparison
| City | Avg Tariff | 3kW Monthly Savings | Payback (3kW) |
|---|---|---|---|
| Mumbai (MSEDCL) | ₹9–12/unit | ₹3,200–5,400 | 1.5–2.5 years |
| Delhi (BSES/Tata) | ₹8–12/unit | ₹2,800–5,400 | 2–3 years |
| Bangalore (BESCOM) | ₹7–10/unit | ₹2,500–4,500 | 2–3 years |
| Jaipur (JVVNL) | ₹7–10/unit | ₹2,500–4,500 | 2–3 years |
| Hyderabad (TSSPDCL) | ₹7–9/unit | ₹2,500–4,050 | 2.5–3.5 years |
The 25-Year Picture
A 3 kW solar system with ₹92,000 net cost:
- Year 1–3: Recover investment
- Year 4–25: Pure savings — ₹2,500–3,500/month × 22 years = ₹6.6–9.2 lakh
- Electricity rates will rise 5–8% per year — making solar MORE valuable over time
When Is Solar NOT Worth It?
- Bill under ₹800/month — payback period too long
- Rented property — you won't recoup investment
- Heavy shading — output drops 30–50%
- Planning to move within 3 years