A business can put solar on its roof in two ways. It can buy the system outright (CAPEX) or let a solar company install and own it and pay only for the power (RESCO, also called the OPEX model).
CAPEX: buy and own it
You pay for the system upfront and own it for its whole life. Published 2026 prices for turnkey commercial rooftop plants run roughly ₹38 to ₹50 per watt-peak, or ₹38,000 to ₹50,000 per kW. Owning gives the lowest cost per unit over the system’s life, and a tax-paying company can claim 40% accelerated depreciation in the first year.
RESCO: pay per unit
A developer finances, builds, owns and runs the plant on your roof. You sign a 15 to 25 year agreement and pay only for the units it generates. Published 2026 tariffs run about ₹4.50 to ₹5 a unit. Savings start in month one and the cost stays an operating expense.
Side by side
| CAPEX | RESCO | |
|---|---|---|
| Upfront cost | Full system price | Nothing |
| Cost per unit over life | Lowest | Higher (developer’s margin) |
| Accelerated depreciation | Yes, 40% in year one | No, you don’t own it |
| Maintenance | Your responsibility | Developer’s responsibility |
| Best for | Owned premises, tax-paying firms | Leased premises, capital-light firms, hospitals and schools |
Example
A 250 kW system at ₹40,000 per kW costs ₹1 crore upfront. With a ₹9 grid price and about 3.75 lakh units a year, it saves roughly ₹33 lakh a year and pays back in about three years. On a ₹4.75 RESCO tariff the same roof saves about ₹16 lakh a year with no investment.
Related: accelerated depreciation, net metering.
Sources
Figures last checked on 26 September 2026.