Commercial Solar Calculator India 2026
For businesses and industry. Work out your ROI and payback, the accelerated depreciation tax benefit, and whether buying the system (CAPEX) or a zero-investment RESCO/PPA (OPEX) deal saves you more.
1 Your system
Commercial & industrial rooftop systems typically run from 25 kW to several MW. Note: PM Surya Ghar subsidy is residential-only; commercial relies on depreciation instead.
C&I solar runs roughly ₹35–₹50 per watt installed in 2026, falling with system size.
2 Tariff & tax
C&I tariffs in India have climbed to ₹8–₹14/unit in many states — the high tariff is what makes commercial solar pay back so fast.
The corporate tax rate at which depreciation reduces your taxable profit. Most Indian companies are at 25% (or ~25–35% with surcharge/cess).
Under Section 32, businesses can depreciate 40% of the asset value in year 1, cutting taxable profit. The remaining value depreciates on a written-down basis after that.
3 RESCO / PPA comparison — optional
In a RESCO/OPEX model a developer owns the plant on your roof and you buy the power at a fixed rate (often ₹4.5–₹6.5/unit) for 15–25 years. Zero investment, but lower savings and no ownership or depreciation.
Indicative estimates only. Depreciation rules (Section 32), tax rates, net-metering caps and tariffs vary and change by notification. Consult a chartered accountant for the exact tax treatment for your business. Confirm figures before investing.
How commercial solar economics work in India
40% × cost × tax rate. That lowers your effective net cost and speeds payback.RESCO / OPEX (PPA): a developer funds and owns the plant; you simply buy the power at a fixed rate below the grid. Zero capital, zero maintenance, but lower lifetime savings and no depreciation or ownership.
LCOE (levelised cost) is the system cost spread over 25 years of generation — for commercial solar it's typically ₹2–₹3/unit, far below the ₹8–₹14 grid tariff, which is the arbitrage. Consult a CA for exact tax treatment.
Commercial solar in India: the business case
For Indian businesses, rooftop solar is often an even stronger investment than for homes. Commercial and industrial electricity tariffs are typically higher than residential ones, daytime operation aligns perfectly with solar generation, and businesses can claim accelerated depreciation as a tax benefit. Many commercial systems pay back in just a few years and then deliver decades of low-cost power, improving the bottom line and supporting sustainability goals. This calculator estimates the ROI, payback and tax benefit, and compares owning the system outright with a third-party (RESCO/PPA) model.
Tax and tariff rules change, so the figures here are dated references; confirm current depreciation rules and your tariff with a qualified advisor before deciding.
Accelerated depreciation: the key tax lever
The standout financial benefit for businesses is accelerated depreciation, which lets a company write down a large portion of the solar asset's value against taxable income early in its life — currently up to around 40% in the first year for eligible businesses. For a profitable, tax-paying business, this brings forward a substantial tax saving, effectively reducing the net cost of the system in its first couple of years and shortening payback significantly. The exact benefit depends on your tax position and current rules, so it's worth modelling with your accountant, but it's often what tips commercial solar from "good" to "compelling."
Why daytime operation suits businesses
Most businesses consume the bulk of their electricity during daylight working hours — exactly when solar generates. That means a high share of self-consumption at the full (high) commercial tariff, rather than exporting cheaply. Offices, factories, cold storage, retail and the like can offset a large part of their daytime load directly, which is the most valuable form of solar saving. Combined with higher commercial tariffs, this daytime alignment is why commercial payback is often faster than residential, even without a residential-style subsidy.
CAPEX vs RESCO/OPEX: two ways to go solar
Businesses can adopt solar two ways. Under the CAPEX (ownership) model, the business buys the system, captures all the savings and the depreciation benefit, and gets the best long-term returns — but funds the upfront cost. Under the RESCO or PPA (OPEX) model, a developer installs and owns the system on your roof and you simply buy the power it generates at an agreed, usually lower-than-grid tariff — no upfront cost, but lower long-term savings and no depreciation benefit, since you don't own the asset. CAPEX suits profitable businesses that can use the tax benefit and want maximum returns; RESCO suits those wanting zero upfront cost and a simple, immediate saving. The calculator compares both so you can see the trade-off for your situation.
Frequently asked questions
For most businesses, yes — often more so than residential. Higher commercial tariffs, strong daytime self-consumption and the accelerated-depreciation tax benefit commonly produce payback in just a few years, followed by decades of low-cost power. Run your figures through the calculator for an estimate.
A tax provision letting businesses write down a large share of the solar asset's value (currently up to around 40% in year one for eligible firms) against taxable income early on, bringing forward a significant tax saving and shortening payback. The exact benefit depends on your tax position and current rules.
Ownership (CAPEX) gives the best long-term returns and the depreciation benefit but requires upfront funding. A RESCO/PPA (OPEX) model needs no upfront cost — you just buy the power at an agreed tariff — but delivers lower long-term savings and no tax benefit. The right choice depends on your cash position and tax profile.
No — PM Surya Ghar is a residential scheme. Commercial solar's incentives are different, centred on accelerated depreciation and the inherent savings from offsetting higher commercial tariffs, rather than a direct capital subsidy. That's why the business case rests on tax benefit and tariff savings, which this calculator models.