Introduction
India's commercial and industrial (C&I) solar sector added a record 36.6 GW of capacity in 2025 — a 43% year-over-year increase. Yet the single biggest barrier for businesses remains the same: upfront capital. A 1 MW commercial solar installation typically costs ₹4–6 crore, a figure that pushes many businesses to delay or abandon solar adoption entirely.
This guide covers the major solar financing models available to Indian C&I businesses in 2026:
- Outright purchase and term loans
- Power Purchase Agreements (PPAs) and leases
- Government-backed schemes and subsidies
- Group captive and open-access structures
Whether you run a manufacturing unit, IT park, hospital, or data centre, understanding these options helps you pick the right structure without overpaying or locking into unfavourable terms.
TLDR: Solar Business Financing Options at a Glance
- Own the system outright with CAPEX — maximum long-term savings with full control over your asset
- Zero upfront cost with OPEX/PPA — pay only for electricity generated while a third party owns and maintains the system
- Solar loans let you borrow to own, retain all tax benefits, and repay from energy savings at rates starting from 7.75%
- Group captive structures let you co-invest in off-site plants with minimal equity for ₹3-5/kWh savings and regulatory exemptions
- 40% accelerated depreciation, state subsidies, and ISTS waivers apply across models — making solar financially attractive regardless of which route you choose
CAPEX vs OPEX: The Foundational Choice in Solar Financing
Understanding the Core Distinction
CAPEX (Capital Expenditure) means your business owns the solar asset — it appears on your balance sheet, qualifies for depreciation, and all savings flow directly to you. OPEX (Operating Expenditure) means a third party owns the system and you pay a per-unit tariff or fixed monthly fee — no asset ownership but also no capital outlay.
When CAPEX Makes Sense
CAPEX suits businesses that can put the asset to full financial use. Key indicators:
- Healthy balance sheet with capacity to absorb upfront spend
- Sufficient tax appetite to absorb 40% first-year accelerated depreciation
- Long-term facility ownership (not operating on leased premises)
- Priority on maximizing 20-25 year savings over capital preservation
Manufacturers, IT parks, data centres, and process industries typically fit this profile. With payback periods of 3-5 years, CAPEX delivers the highest lifetime returns of any financing structure.
When OPEX Makes Sense
OPEX suits businesses where capital preservation or operational flexibility is the priority. Strong indicators include:
- Operating from leased premises with no long-term facility commitment
- Limited capital budget or competing investment priorities
- Preference for predictable, fixed energy costs without O&M responsibility
- Appetite for clean energy without the complexity of asset ownership
Hotels, hospitals, and commercial complexes commonly choose this route. The trade-off is straightforward: OPEX preserves working capital but transfers the long-term financial upside to the developer.
The ROI Trade-off
10-Year Cost Comparison Example (1 MW System):
- CAPEX: ₹5 crore upfront → ₹2 crore depreciation benefit → Net cost ₹3 crore → 10-year savings ₹8 crore → Net gain ₹5 crore
- OPEX/PPA: ₹0 upfront → ₹4.5/kWh tariff with 3% annual escalation → 10-year cost ₹5.5 crore → Net gain ₹2.5 crore
The right choice depends on your balance sheet strength, facility tenure, and how you weigh capital risk against lifetime returns — not on which model looks better in isolation.
Solar Financing Options for C&I Businesses: A Complete Breakdown
Solar Loans and Green Term Loans
The business borrows from a bank or NBFC to fund the CAPEX solar installation, retains full ownership, and repays the loan from energy cost savings. Typical tenures run 5-10 years with competitive interest rates.
Public sector banks and green-finance lenders have been offering preferential rates — Bank of Baroda's partnership with Tata Power provides collateral-free loans up to ₹10 crore starting from 7.75%, while IREDA prices private sector borrowers at 8.65%-9.65%.
Key Eligibility Factors Indian Lenders Assess:
- Credit rating (minimum "A-" for longer tenures)
- Energy audit reports showing projected savings
- EMI coverage ratio (savings should exceed monthly loan payments)
- Collateral (though CGTMSE schemes enable collateral-free loans up to ₹10 crore)
- Installation type (rooftop vs. ground-mounted)
Beyond private lenders, government-backed institutions offer larger ticket sizes. SIDBI finances MSMEs up to ₹50 crore at MCLR-linked rates, while SBI's Surya Shakti product provides term loans up to ₹50 crore with 15-year repayment for businesses with long-term PPAs.
For businesses weighing ownership against flexibility, Power Purchase Agreements offer a zero-capex alternative worth comparing.
Power Purchase Agreements (PPAs) and the RESCO Model
A developer (RESCO — Renewable Energy Service Company) funds, installs, owns, and operates the solar system on your premises or off-site. Your business signs a long-term agreement (typically 15-25 years) to buy electricity at a fixed or escalating tariff lower than DISCOM rates. This is the most common zero-capex route for Indian C&I businesses.
Trade-offs to Weigh:
| What You Gain | What You Give Up |
|---|---|
| No upfront capital outlay | No asset ownership or depreciation benefits |
| Predictable energy tariff | Contractual lock-in for 15-25 years |
| Partial hedge against DISCOM escalation | 3% annual tariff escalation from Year 2 onward |
| Reduced carbon footprint | Missed accelerated depreciation tax benefits |
Standard RESCO PPA templates include a 3% annual tariff escalation clause starting from the second operational year — and over a 15-25 year term, this compounds significantly.
Why Escalation Clauses Matter:
A PPA starting at ₹4/kWh with 3% annual escalation reaches ₹5.52/kWh by year 10 and ₹7.61/kWh by year 20. If DISCOM rates don't escalate as rapidly, your "savings" shrink over time.
Before signing any PPA, comparing tariff offers across multiple developers is critical. Opten Power's marketplace lets C&I businesses benchmark PPA tariffs, savings projections, and developer credentials across India's top power producers — covering 16 states with real-time IRR, payback, and regulatory analysis to support negotiation.
Group Captive and Open Access Solar
The Group Captive Model:
Under India's Electricity Act, a business can become a co-owner (minimum 26% equity collectively) in an off-site solar plant and draw power at near-generation cost, bypassing DISCOM retail tariffs entirely. The March 2026 Electricity (Amendment) Rules overhauled compliance requirements, allowing the 26% equity and 51% consumption thresholds to be met collectively by the Association of Persons (AoP) rather than strictly proportionally per user.
This model suits heavy industries — steel, cement, textiles — with large 24x7 power demands. Per-unit savings typically land at ₹3-5/kWh, with additional regulatory benefits including wheeling charge exemptions in several states.
Applicable Open Access Charges (State-Specific):
- Maharashtra: Cross-Subsidy Surcharge ₹1.79/kWh + Additional Surcharge ₹1.39/kWh + Wheeling ₹0.60/kVAh
- Gujarat: Additional Surcharge ₹1.00/kWh (Oct 2025-Mar 2026) + Banking charge ₹1.5/kWh
Open Access Procurement:
Even without equity ownership, businesses above the 100 kW contracted demand threshold (under Green Energy Open Access Rules) can procure solar power from third-party generators through open access. Opten Power's real-time DISCOM intelligence covers standardized landing prices across states to help businesses calculate true landed cost after accounting for transmission, wheeling, and cross-subsidy charges.
Government Schemes and Subsidized Financing
PM Surya Ghar Muft Bijli Yojana:
Primarily targeted at residential consumers — C&I applicability is limited. Businesses should focus on MNRE's rooftop solar programs and state-level capital subsidy schemes instead.
SIDBI and IREDA Financing:
India's dedicated renewable energy finance institutions offer concessional debt for solar projects. IREDA provides loans up to 70% of project cost with 10-15 year repayment periods at 8.65%-9.65% interest rates. SIDBI offers direct finance to MSMEs up to ₹50 crore covering 75% of total project cost with repayment up to 10 years.
Tax Incentives and Government Support for Solar in India 2026
Accelerated Depreciation (AD) Benefit
Under the Income Tax Act, businesses can claim 40% accelerated depreciation on solar plant and machinery in the first year, significantly reducing tax liability. This is one of the most powerful financial levers available exclusively to asset owners (CAPEX model).
Effective Tax Saving Example:
For a ₹5 crore solar installation with 40% depreciation:
- Year 1 depreciation: ₹2 crore
- Corporate tax rate: 25% (for companies with turnover under ₹400 crore)
- Tax saving: ₹50 lakh in Year 1
This substantially improves project IRR and shortens payback periods.
GST Benefits and Input Tax Credit
As of September 2025, the GST rate on renewable energy components (solar panels, inverters, etc.) was reduced from 12% to 5%. For EPC contracts, 12% GST applies to 70% of the contract value and 18% to the remaining 30%.
However, recent AAR rulings have denied Input Tax Credit (ITC) on solar plant installation inputs — a development that raises real cost concerns for businesses financing under the CAPEX model.
What About a "Business Tax Credit for Solar"?
India offers no direct Investment Tax Credit (ITC) equivalent to the US system. The comparison often confuses buyers researching financing options across markets:
| Incentive | India | United States |
|---|---|---|
| Direct tax credit | Not available | 30% ITC (Inflation Reduction Act) |
| Depreciation benefit | 40% accelerated (Year 1) | MACRS schedule |
| Capital subsidy | State-level schemes | Federal + state stacking |
India's primary incentives are accelerated depreciation and state-level capital subsidies — not a credit applied directly against the tax bill.
ISTS Charge Waiver
Solar projects commissioned before June 30, 2025, were eligible for 100% Inter-State Transmission System (ISTS) charge waivers — a significant cost benefit for businesses procuring power from remote solar plants.
The waiver has now expired, significantly changing the economics of inter-state solar procurement. Most businesses are redirecting focus toward intra-state projects where transmission costs remain manageable.
How to Choose the Right Solar Financing Model for Your Business
The Three-Question Decision Framework
1. Do you own or lease your facility?
- Ownership favors CAPEX/loan
- Leased premises push toward PPA/RESCO
2. Do you have a tax appetite?
- Profitable businesses benefit most from CAPEX + accelerated depreciation
- Loss-making or low-tax entities should consider OPEX
3. What is your power demand profile?
- 24x7 high-load industries (steel, cement, data centres) → Group captive or open access
- Moderate-load commercial entities → Rooftop PPA
- High grid tariff businesses (₹10-15/kWh) → Third-party open access
Compare Total Landed Cost, Not Just Headline Tariff
A full financial comparison requires these inputs:
- DISCOM tariff escalation assumptions (historical average: 4-6% annually)
- Open access charges (CSS, AS, wheeling, transmission)
- O&M costs (₹3-5 lakh per MW annually)
- Depreciation benefit (40% Year 1 for CAPEX)
- Loan interest and tenure
- Expected solar generation yield (CUF: 18-22% depending on location)
Running this analysis manually across multiple developers is time-intensive. Opten Power's platform generates IRR, payback, and regulatory cost breakdowns in real time — across financing models and project types — so you can compare like-for-like before committing.
Red Flags in Financing Contracts
Before signing any solar financing contract, check for these clauses:
- Escalation caps: Uncapped annual tariff hikes of 3%+ compound heavily over a 15-25 year contract
- Exit penalties: Some agreements lock you in even when the developer fails to meet generation targets
- Generation guarantees below 90%: Industry standard is 90% performance assurance — anything lower shifts risk to you
- Change-of-law provisions: These transfer the cost of future regulatory changes (open access charges, grid fees) from the developer to your business
First-time solar buyers who miss these clauses typically discover the gap only at renewal — by which point renegotiation leverage is limited.
Frequently Asked Questions
What tax benefits can Indian businesses claim on a solar installation?
Indian businesses benefit from 40% accelerated depreciation on solar assets in year one under the Income Tax Act, along with state capital subsidies and GST input tax credits. There is no direct investment tax credit equivalent, but accelerated depreciation alone can deliver significant first-year tax savings.
What is the difference between CAPEX and OPEX solar financing models?
CAPEX means the business purchases and owns the solar system, gaining tax benefits and maximum savings with payback in 3-5 years. OPEX means a third party owns the system and the business pays only for the power it consumes, with no upfront investment required but lower long-term returns.
What is a corporate PPA and how does it work for a business in India?
A corporate PPA is a long-term agreement where a solar developer installs and operates a system (on-site or off-site) and the business buys the generated electricity at a pre-agreed tariff — typically ₹3.5-4.5/kWh with 3% annual escalation — for 15-25 years, with zero capital investment from the business.
Can a business claim accelerated depreciation on a solar installation?
Yes, businesses that own their solar assets under a CAPEX model can claim 40% accelerated depreciation in the first year under the Income Tax Act, reducing taxable income materially in year one. This benefit is not available under PPA/RESCO models where the developer owns the asset.
Which solar financing option is best for a large manufacturing or industrial company?
Large C&I consumers with 24x7 operations typically benefit most from group captive or open access arrangements that reduce dependence on DISCOM tariffs, or from CAPEX purchase to maximize accelerated depreciation. The right choice depends on facility ownership, power demand, and tax position.
How long does it take to get ROI on a business solar installation in India?
Payback periods for CAPEX solar installations in India typically range from 3-5 years depending on system size, financing cost, local tariff rates, and available incentives. After payback, businesses enjoy electricity at minimal O&M cost for the remaining 15-20 years of the system's life.
