Commercial & Industrial Solar in India: 2026 Guide

For an Indian business paying industrial electricity tariffs, solar has become one of the clearest levers on operating cost — and, increasingly, on compliance and competitiveness too. But "going solar" is not a single decision. It's a series of them: how to fund it, which procurement route to use, how policy affects your project, whether to add storage, and how to read a contract that may run for two decades. This guide brings those decisions together in one place, with links to detailed explainers on each.

Commercial and industrial (C&I) solar in India covers on-site rooftop solar and off-site green open access, funded through either CAPEX (you own the system) or OPEX/RESCO (a developer owns it and you buy the power). For most C&I buyers, the sensible path is to optimise rooftop solar first — it displaces daytime grid power without the open-access wheeling and transmission charge stack — then layer open access and storage for larger renewable targets. The right choices depend on your electricity tariff, load profile, roof, tax position, and state regulations, so the reliable numbers come from modelling your specific facility rather than a headline figure. This guide walks through each decision: funding, cost, policy (ALMM), procurement routes, storage, contracts, and sector-specific considerations.

Here's the full picture, decision by decision.

Why is C&I solar growing so fast in India?

Because commercial power carries relatively high landed costs in many states, solar costs have fallen over the longer term, and renewable energy is increasingly tied to decarbonisation targets, disclosure requirements, and customer expectations — not just cost savings. India's rooftop solar market reached about 27.6 GW of cumulative capacity, with about 9.2 GW added during calendar year 2025, according to CRISIL Intelligence. The C&I segment is an important part of India's rooftop solar market, while off-site green open access for C&I consumers has also expanded rapidly.

Three forces are driving it:

• Cost. Commercial and industrial consumers in many states face relatively high landed electricity costs, particularly after demand charges and other applicable components are included, so displacing grid units with self-generated solar has a direct effect on operating cost.

• Policy and market maturity. Clearer rules for open access, a growing domestic manufacturing base, and established funding models have made C&I solar more accessible than it was even a few years ago.

• Compliance and customer pressure. Corporate renewable targets, ESG disclosure requirements, and supply-chain expectations from large buyers are increasingly tying renewable energy to competitiveness for many businesses, not just cost.

The rest of this guide is about turning that opportunity into a sound decision for your specific facility.

How do you fund C&I solar: OPEX vs CAPEX?

One of the first major decisions is who owns and funds the system. Under CAPEX, you fund and own it and capture its full economics; under OPEX/RESCO, a developer funds and owns it and you buy the power with no upfront capital. Each suits a different balance sheet and tax position:

• CAPEX can deliver higher lifetime savings when you have capital to deploy, can use the applicable tax benefits, and achieve competitive project economics — along with asset ownership.

• OPEX/RESCO works when you'd rather keep capital in your core business, want the developer to handle most of the financing, operations, and maintenance responsibilities, and are comfortable buying power under a long-term contract.

We compare the two in depth — costs, tax, risk, and a decision framework — in OPEX vs CAPEX solar for business. If the "zero upfront cost" of OPEX sounds too good to be true, our honest breakdown of the model — zero-investment solar: what's the catch — explains exactly what you trade for it (ownership and some lifetime savings, in exchange for zero capital and transferred risk). The important point: OPEX doesn't eliminate risk, it reallocates it.

What does C&I solar cost in India?

There is no single national price — project cost varies with system size, module technology and sourcing, roof conditions, site complexity, and grid requirements. Larger systems generally achieve lower per-kW costs, but complex sites can sit well above any general figure, and 2026 has seen cost pressure in some module configurations (notably Chinese-module systems), making older benchmarks less reliable.

Rather than trust a headline number, the right approach is to compare complete installed-system quotations (not battery-only or panel-only prices) and, for any funding or savings estimate, benchmark against your own current landed grid tariff — pull your last 12 months of DISCOM bills and divide total cost by units consumed. We explain how project cost is actually built up, and why the "no national benchmark" reality is more useful than a fake number, in rooftop solar cost in India for C&I buyers.

How does solar policy (ALMM) affect a C&I project in 2026?

India's ALMM framework sets eligibility requirements for solar modules and, for applicable project categories, solar cells — and 2026 brought an important, time-sensitive change for net-metering and open-access projects. ALMM List-II for solar PV cells became mandatory for applicable projects from June 1, 2026. MNRE's July 18, 2026 order subsequently created a limited exemption window through December 31, 2026 for eligible net-metering and open-access renewable-energy projects, and an August 4, 2026 clarification further defined treatment based on project category, bid-submission date, and connection type.

Two points matter for a C&I buyer. First, eligibility is tied to commissioning (not ordering): eligible projects commissioned by December 31, 2026 can use cells not on List-II, while from January 1, 2027 List-II applies where required. Second — and often overlooked — certain behind-the-meter projects used solely for captive consumption are outside ALMM List-I and List-II under the specified conditions (with a stated Government/PSE exception). So this is not a universal deadline for every C&I rooftop project: the applicable requirement should be confirmed based on your project's exact configuration, connection type, and commissioning date. Two detailed explainers cover this:

• What ALMM List-II means for C&I buyers — the evergreen explainer on the framework itself.

• The December 31, 2026 ALMM deadline: a C&I action guide — the time-sensitive guide on the exemption window and what to do before it closes.

ALMM List-II is being updated regularly, so any project near a regulatory or procurement boundary should confirm the latest MNRE list and applicable requirements.

Rooftop or open access: which procurement route?

Rooftop solar generates on your own premises, avoiding the open-access wheeling and transmission charges associated with off-site procurement; green open access buys renewable power from a large off-site plant through the grid, unlocking far greater scale but carrying state-specific charges. They solve different problems, and for many C&I buyers the strongest strategy combines them:

• Rooftop as a logical first layer, because self-consumed on-site generation avoids the transmission and wheeling charges associated with open access and directly offsets daytime consumption.

• Open access for the residual, because many facilities consume far more than their roof can generate — or want a much higher renewable share. Where roof area is insufficient or unsuitable, open access can provide the additional scale. Many larger manufacturers use a group-captive structure, which can provide relief from certain open-access charges (such as cross-subsidy surcharge), though captive eligibility and the resulting charge treatment depend on meeting the applicable ownership and consumption requirements, and the economics are highly state-specific.

We compare the two routes in full — including the charge stack (wheeling, cross-subsidy surcharge, banking), the group-captive framework, and the 2026 rule changes — in rooftop solar vs green open access for industrial consumers.

A closely related decision is how your generation is credited: net metering vs net billing explains why, as billing shifts toward crediting exported power below the retail rate, self-consumption has become the key driver of solar value.

Does a C&I facility need battery storage?

Not always — but where a facility has sharp, high demand charges or wants to shift solar into non-solar hours, battery storage (BESS) can add real value. A behind-the-meter battery stores electricity (from the grid at off-peak times or from on-site solar) and discharges it during expensive peak periods, which can reduce demand charges through peak shaving — where the utility's demand-charge methodology recognises the resulting reduction in billed peak demand — as well as enable time-of-day arbitrage and increase solar self-consumption.

Whether it pays off depends entirely on your demand-charge structure, load profile, and tariff — there's no national payback figure. We cover the mechanics, the economics, and how to size a system in battery storage for Indian industry: how it cuts demand charges. Storage is usually best considered once rooftop (and, where relevant, open access) is in place, as the piece that manages peaks and timing.

What should you check in a solar PPA?

If you go the OPEX route, the PPA governs a relationship that can last 10 to 25 years — so the contract terms matter more than the headline tariff. The clauses that decide whether a PPA is a good deal include the tariff and its escalation, the tenure and lock-in, exit and termination terms, change-in-law protection, performance guarantees, and — for open access — the all-in landed cost after charges.

Two guides cover the contract in detail:

• Solar PPA terms C&I buyers should check before signing — the six clause areas to scrutinise, and why to compare offers on modelled full-term cost rather than year-one tariff.

• What happens when a solar PPA ends — the end-of-term options (renew, buy, or remove), the India-specific nominal-transfer structure, and why the outcome is set by clauses you agree to at signing.

Is solar right for my type of facility?

Most energy-intensive C&I facilities with adequate roof area and strong daytime load are good candidates — but the specifics differ by sector. The common thread is matching generation to on-site consumption; the differences are in load profile, roof type, and sector-specific drivers. We've covered the major segments:

• Rooftop solar for manufacturing plants — the core industrial case: process loads, shift patterns, and sizing to consumption.

• Solar for warehouses and cold storage — why cold storage often has a stronger solar fit, because refrigeration loads can continue across much of the day and night, and how dry warehouses differ.

• Solar for the automotive and auto-component sector — where cost savings meet supply-chain sustainability expectations (OEM renewable targets, sustainability disclosures, and increasing carbon-data requirements from global customers).

Whatever the sector, the reliable answer comes from modelling your actual load, tariff, and roof — not a per-square-foot rule of thumb.

How to approach a C&I solar decision: a practical sequence

Pulling it together, a sound way for most C&I buyers to approach solar:

1. Establish your baseline. Pull your last 12 months of electricity bills and work out your landed cost per unit — the number every option must beat.

2. Optimise rooftop as the first layer. Assess your roof (area, structure, shading) and size a system to your daytime load. Self-consumed on-site generation is a relatively simple first layer because it doesn't incur the open-access wheeling and transmission charge stack.

3. Choose a funding model. CAPEX if you have capital and can use the tax benefits; OPEX/RESCO if you'd rather preserve capital and transfer risk.

4. Model the residual. If your demand exceeds what the roof can supply and you have a larger renewable target, evaluate open access (and group captive) for your state.

5. Consider storage where demand charges or timing justify it.

6. Read the contract carefully if you go OPEX — tariff, escalation, exit, and end-of-term terms.

7. Check policy timing, especially the ALMM position for your project category and commissioning date.

8. Verify every number against your own facility — the recurring theme of this entire guide.

The bottom line for C&I buyers

C&I solar in India in 2026 offers a well-established set of procurement and financing options — but a genuinely good decision still depends on getting the specifics right for your facility. Start with your own electricity baseline, optimise rooftop first, choose the funding model that fits your balance sheet, and layer open access and storage where they earn their place. Read contracts for the full term, not the headline tariff, and check the policy timing for your project. Above all, treat headline savings and payback figures with caution — the reliable numbers come from modelling your actual load, tariff, and roof.

SustVest delivers rooftop solar for C&I buyers across India under OPEX and CAPEX models, with battery storage, in-house monitoring, and O&M — sized and modelled around your actual facility. Ranked #8 in CRISIL Intelligence's CY2025 Top 10 rooftop solar project-developer ranking (India Solar Rooftop Map, December 2025) — a ranking based on the report's stated methodology, not an endorsement — with 84+ projects delivered across 13+ states (company-reported figures). Book a free site assessment to get a facility-specific plan — funding, savings, and payback modelled on your real numbers.

Frequently Asked Questions

What is C&I solar? C&I (commercial and industrial) solar refers to solar power systems for businesses — factories, warehouses, cold storage, commercial buildings, and similar facilities — as opposed to residential rooftops or utility-scale plants. It covers on-site rooftop solar and off-site green open access, funded through either CAPEX (the business owns the system) or OPEX/RESCO (a developer owns it and the business buys the power).

Is solar worth it for a business in India in 2026? For most energy-intensive facilities on industrial tariffs with adequate roof area and daytime load, solar can meaningfully reduce electricity cost, and it increasingly carries compliance and customer-expectation value too. The actual savings and payback depend on your tariff, self-consumption, roof, and funding model, so they should be modelled for the specific facility rather than taken from a headline figure.

Should a business choose CAPEX or OPEX for solar? CAPEX (you fund and own the system) suits businesses with capital to deploy and a tax position that can use the applicable benefits, and it can deliver higher lifetime savings where the project economics are competitive. OPEX/RESCO (a developer owns the system and you buy the power) suits businesses that prefer to preserve capital and transfer much of the financing and operating responsibility to the developer. The renewable-energy benefit is available under either model; the choice is largely financial.

Does rooftop solar cover a business's full electricity demand? Often not, particularly for energy-intensive, multi-shift facilities whose annual electricity demand exceeds what their usable roof area and solar generation profile can supply. Businesses aiming for a high renewable share typically combine rooftop solar with green open access (often via group captive) and sometimes storage, starting with rooftop as the on-site foundation.

How does the 2026 ALMM deadline affect a C&I solar project? Eligible net-metering and open-access projects can be commissioned using cells not on ALMM List-II until December 31, 2026; from January 1, 2027, List-II applies where required. This is not a universal deadline for every C&I rooftop project — project configuration, connection type, bid date, and applicable MNRE provisions can change the treatment, and certain behind-the-meter captive projects are outside ALMM List-I and List-II under specified conditions. Projects should confirm their specific position against current MNRE rules, especially if commissioning close to the deadline.

How do I know what solar will actually cost and save for my facility? There is no reliable national figure — cost and savings depend on your system size, roof, tariff, self-consumption, and funding model. The dependable approach is to establish your current landed grid tariff from your bills, then get a costed, site-specific proposal and compare complete installed-system quotations. Modelling your actual facility is the only way to get accurate numbers.

Sources

• CRISIL Intelligence — India Solar Rooftop Map (December 2025): market capacity (~27.6 GW cumulative, ~9.2 GW added in CY2025); SustVest ranked #8 in the CY2025 Top 10 rooftop solar project-developer ranking

• MNRE / PIB — ALMM framework; List-II (June 1, 2026); July 18, 2026 exemption window to December 31, 2026; August 4, 2026 category clarification (including behind-the-meter captive treatment); List-II revised regularly (8th revision July 22, 9th August 21, 2026)

• Ministry of Power — Green Energy Open Access Rules, 2022; Electricity (Amendment) Rules, 2026 (captive framework: 26% ownership / 51% consumption tests)

• Mercom India Research — Q1/Q2 2026 Solar Open Access Market Reports (open-access additions and C&I demand); Q1 2026 rooftop/module reports (cost trends; Chinese-module cost movements)

• SustVest — the 13 linked cluster posts (funding, cost, policy, procurement, storage, contracts, sectors); 84+ projects, 13+ states (company-reported figures)