Group Captive Solar India 2026, Detailed Setup Guide

Group captive solar is the structure most large Indian factories now use to cut electricity bills without buying the plant outright. Under the Electricity Rules 2005, Rule 3, a group captive plant is a solar park where the captive users collectively hold at least 26% of the ownership (voting equity) and consume at least 51% of the annual generation, in proportion to their shareholding. Get those two thresholds right and you legally side-step the Cross Subsidy Surcharge (CSS) that hits regular open access (OA) buyers, pulling landed tariffs down to ₹4 to 5/kWh against a DISCOM grid rate of ₹8 to 10/kWh. State regulators now verify these tests every financial year, so the structure needs to be designed for compliance from day one.

This guide walks through the 5-Stage Group Captive Setup Path Heaven Green Energy uses across Gujarat, Maharashtra, Tamil Nadu, Karnataka, and Madhya Pradesh, including the SPV (Special Purpose Vehicle) formation rules, the share-purchase math, the open access charge map by state, and where group captive beats CAPEX, OPEX, and IPP (Independent Power Producer) structures on landed cost.

Direct answer. Group captive solar lets industrial consumers together hold ≥26% of the voting equity in a dedicated solar SPV and together consume ≥51% of its annual generation, in proportion to their shareholding, under Electricity Rules 2005. The structure removes Cross Subsidy Surcharge (CSS) and Additional Surcharge, pulling landed tariffs to ₹4 to 5/kWh against a ₹8 to 10/kWh grid rate, typical net savings of ₹2 to 3/kWh over 25 years for textile mills, ceramic clusters, IT parks, and multi-site SMEs.

If you’re an HT industrial consumer with a monthly bill above ₹40 lakh and no rooftop or land of your own, group captive is almost always the cheapest legitimate path. The trade-off is upfront equity, a 12 to 18 month setup window, and ongoing compliance, all manageable with the right SPV partner.

What Group Captive Means Under Electricity Rules 2005

The Ministry of Power’s Electricity Rules 2005, Rule 3, draws a clean line between three structures: regular open access, captive, and group captive. Each has a different cost stack because each is treated differently by the State Electricity Regulatory Commission (SERC) on the surcharge front.

• Regular open access: consumer buys solar power from a third-party generator over the DISCOM grid. Pays full Cross Subsidy Surcharge, additional surcharge, wheeling, transmission, and banking charges. Landed cost typically ₹5.5 to 7/kWh.
• Single captive: one consumer holds at least 26% of the ownership and consumes at least 51% of the generation (often 100% of both). No CSS. Used by very large standalone plants (steel, cement). Landed cost ₹3.5 to 4.5/kWh.
• Group captive: multiple consumers form an SPV and together hold ≥26% of its voting equity, with collective consumption ≥51% of annual generation, shared in proportion to their shareholding within a 10% variation. No CSS or Additional Surcharge; wheeling and transmission charges still apply. Landed cost ₹4 to 5/kWh.

The 26% and 51% tests are checked on a financial-year basis against the SPV’s shareholding and metered consumption data. In Gujarat, GERC’s Green Energy Open Access Regulations, 2024 require the plant and captive users to file an affidavit on generation, consumption and shareholding by 31 October of the following year, and the DISCOM or Commission can verify it with SLDC data. Miss either test in a year and that year’s supply is treated as third-party sale, with CSS and Additional Surcharge payable. This is the single biggest risk to manage, and it is why the SPV structure matters more than the panels themselves.

The 5-Stage Group Captive Setup Path

This is the framework Heaven Green Energy applies on every group captive engagement, five sequential stages with discrete deliverables. The end-to-end window runs 12 to 18 months from feasibility to first unit exported.

Stage 1: Feasibility & Member Anchoring (Month 1 to 3)

Before any SPV paperwork, the project needs an anchor consumer, usually a single industrial buyer with ≥20% of the total offtake. Heaven Green runs a feasibility study covering:

• Annual electricity demand of each prospective member (kWh and load profile).
• Connected DISCOM and HT tariff slab, including current CSS, wheeling, and additional surcharge.
• Site shortlist for the solar park (5 to 30 MW typical, requiring 25 to 150 acres).
• Power evacuation point at the nearest 33 kV / 66 kV / 132 kV substation.
• Indicative landed tariff after CSS waiver and wheeling.

The output is a member-by-member savings sheet, without ₹2 to 3/kWh of indicated savings, the structure rarely justifies its overheads.

Stage 2: SPV Formation & Regulatory Filings (Month 3 to 5)

The SPV is incorporated as a private limited company under the Companies Act 2013, with each consumer subscribing to equity in proportion to their planned offtake. Filings include:

• Registrar of Companies (ROC) incorporation with Memorandum and Articles drafted for power generation.
• Shareholder agreement specifying the 26%/51% covenants, the proportional-consumption rule, exit terms, and dilution triggers.
• Open access application with the State Load Despatch Centre (SLDC) and SERC.
• Land lease or purchase, with conversion to non-agricultural use where applicable.

Stage 3: Member Onboarding & Consumption Sizing (Month 4 to 7)

Each member signs a Power Purchase Agreement (PPA) with the SPV, usually 20 to 25 years, and a Share Subscription Agreement so that members together hold at least 26% of the voting equity. Consumption is sized so the collective demand from members holding equity is ≥51% of expected generation, split in proportion to each member’s shareholding; the residual can be sold to non-equity consumers as regular open access, but that share carries CSS and is treated as a separate revenue stream.

For a deeper view on how PPAs are negotiated under similar structures, see our how solar PPAs and RESCOs work in India guide.

Stage 4: Equity Funding & EPC Award (Month 6 to 10)

Member equity is called in tranches against capex milestones. Typical financing stack for a 20 MW group captive park:

• Member equity, enough for members together to hold at least 26% of the SPV’s voting equity.
• Sponsor equity, from the developer, for the balance of the equity.
• Senior debt for the rest of the project cost, from lenders such as IREDA, SBI or PFC, at rates set by the lender.

The Engineering, Procurement and Construction (EPC) contract is awarded against fixed CAPEX and a 25-year performance guarantee. Heaven Green’s solar EPC services handle ground-mount parks across this MW range; for utility-scale builds see our ground mount solar park page.

Stage 5: Commissioning, Banking & Compliance (Month 10 to 18)

Commissioning involves the Chief Electrical Inspectorate (CEI) clearance, SLDC scheduling registration, and grid-synchronisation tests. Banking arrangements are signed with the DISCOM on the terms in the state’s current regulations; in Gujarat, the 2021 solar policy set banking charges of ₹1.50/unit for demand-based consumers and ₹1.10/unit for MSME and other consumers. Compliance becomes recurring:

• Annual filing of shareholding and consumption details (in Gujarat, an affidavit by 31 October of the following year).
• Consumption data proving ≥51% collective offtake in proportion to shareholding.
• Quarterly energy accounting with SLDC.

26% Equity + 51% Consumption Rule Explained

The two thresholds are easy to state and trickier to engineer. Here’s how the math actually works for a 20 MW solar park generating ~36 million kWh annually, with three members.

Member	Annual demand (kWh)	Share of total offtake	Equity held	Equity value (₹ Cr)
Anchor textile mill	14.5 million	40%	40%	28.0
Ceramic cluster (4 units)	11.0 million	30%	30%	21.0
Multi-site IT park	11.0 million	30%	30%	21.0
Total members	36.5 million	100%	100%	70.0 (project cost ₹98 Cr)

Project cost ≈ ₹98 Cr; member equity ≈ ₹70 Cr (~70% of project); the balance is sponsor equity plus senior debt. The members together hold 100% of the member equity pool, well past the 26% aggregate test, and collective consumption is 100% of generation, well past 51%, with each member’s offtake matching its shareholding.

The formula Heaven Green uses for each member:

Member equity (₹) = (Member’s planned offtake ÷ Total member offtake) × Total member equity pool

The 26% test applies to the captive users in aggregate, every financial year. The consumption test is stricter: for an SPV, the captive users must consume at least 51% of net generation in proportion to their shareholding, within a 10% variation. If a textile mill holding 40% of the shares cuts production and its consumption drops to 18% of the captive offtake, it falls outside that band and puts the structure at risk. Plan for demand variation by under-sizing the park slightly.

The 51% test is the harder one to engineer because it tracks actual metered consumption over the financial year. A common mistake is sizing the park to match peak member demand; in reality, plant shutdowns for maintenance, seasonal production cycles, and demand contraction during slowdowns can pull collective consumption below 51%. Heaven Green uses a 90 to 95% sizing rule, generation expected at 95% of the lowest forecast year of demand, so the 51% threshold has natural headroom even in a weak production year. The residual generation in strong years is sold as banked surplus or to non-equity buyers as regular open access.

A second subtle point: the 51% threshold is collective, but each member’s share of it must stay in proportion to its shareholding within a 10% variation. So a weak performer in one year cannot simply be balanced by stronger offtake from another member. Also, any inter-se sale of energy between equity holders is treated as third-party sale, not captive consumption. The shareholder agreement should include a “true-up” mechanism so a member who consistently under-consumes is diluted, with shareholding realigned to actual offtake at the start of the year.

Tariff Savings Compared to Grid + OA Charges

Here is an illustrative all-in landed cost comparison for an HT industrial consumer in Gujarat. The figures are indicative planning numbers, not taken from a Gujarat Electricity Regulatory Commission (GERC) order, so model your own project against the current orders.

Cost component	DISCOM grid (HT)	Regular open access	Group captive
Energy charge	₹7.20	₹3.40	₹3.40
Cross Subsidy Surcharge (CSS)	,	₹1.65	₹0 (waived)
Additional surcharge	,	₹0.55	₹0 (not applicable to captive)
Wheeling charge	included	₹0.85	₹0.55
Transmission charge	included	₹0.40	₹0.40
Banking charge (illustrative)	,	₹0.35	₹0.35
Electricity duty	₹0.85	₹0.85	₹0.85
Landed cost (₹/kWh)	₹8.05	₹8.05	₹5.55

The grid and regular OA land roughly the same, which is exactly why regular OA never became dominant in India. Group captive cuts ₹2.50/kWh in this illustrative Gujarat example, because captive use avoids both CSS and Additional Surcharge under Gujarat’s solar policy. For an HT mill consuming 36 million kWh annually, that’s about ₹9 crore of recurring savings.

For a full structural comparison of finance models, including how CAPEX, OPEX, and group captive trade off, read our OPEX vs CAPEX guide for 2026.

Three line items deserve a closer look because they are the ones most often mis-estimated by first-time SPV members. Cross Subsidy Surcharge is set by the SERC and recalculated each year, the ₹1.65/kWh used above is illustrative, not a permanent figure. Always model with the latest tariff order, and stress-test the savings against a ±20% CSS movement.

Wheeling charges vary with voltage class. A consumer connected at 132 kV pays a lower wheeling charge than one at 33 kV because fewer transformation stages are involved. If your industrial estate is on 132 kV, the wheeling line in the table above can drop another ₹0.15/kWh.

Banking is the most under-appreciated cost. Depending on the state, the banking charge is levied in kind (a share of banked energy) or in cash per unit; in Gujarat, the 2021 solar policy set ₹1.50/unit for demand-based consumers and ₹1.10/unit for MSME and other consumers. On a park generating 36 million kWh, the banking cost runs to lakhs of rupees a year. Tight scheduling and demand-aligned generation profiles minimise this leakage.

Talk to our group captive team. We’ve structured group captive parks across Gujarat, Maharashtra, Tamil Nadu, Karnataka, and Madhya Pradesh, from anchor sizing through SPV formation to commissioning. Request a feasibility study →

Group Captive vs CAPEX vs OPEX vs IPP, Where Each Wins

Four structures dominate Indian commercial and industrial solar in 2026. Each fits a different balance-sheet position.

Dimension	CAPEX (own)	OPEX (PPA)	Group Captive	IPP (third-party)
Ownership	100% consumer	Developer	SPV (≥26% consumer equity)	Developer
Upfront cost	100% project cost	₹0	Member share of SPV equity	₹0
Landed tariff	₹2.5 to 3/kWh (post-AD)	₹4 to 5.5/kWh	₹4 to 5/kWh	₹5.5 to 7/kWh
CSS exposure	None (rooftop)	None (rooftop OPEX)	Not applicable while captive tests are met	Full CSS payable
Accelerated Depreciation benefit	Direct to consumer	Captured by developer	Claimed by the SPV (asset owner)	Captured by developer
Tenure flexibility	Forever	15 to 25 years	20 to 25 years	15 to 25 years
Best for	Cash-rich mid-size factory	Cash-light SME, rented roof	Multi-member large industrial	Light-asset consumer

The decision tree is straightforward: if you own the roof or land and have surplus cash plus a profit position to absorb depreciation, CAPEX wins. If you have no land but want zero CAPEX, OPEX or IPP wins depending on tariff. If your consumption is large, your DISCOM CSS is high, and you can put up the member equity, group captive wins by 15 to 20% on landed tariff over its life.

For a tax-driven CAPEX view, see our accelerated depreciation guide. For the rooftop OPEX comparison specifically, see OPEX vs CAPEX solar.

A simple rule of thumb our deal team uses with CFOs: if your monthly HT bill is under ₹10 lakh, run CAPEX rooftop on whatever roof you have, and ignore group captive. If it’s ₹10 to 40 lakh, run OPEX rooftop and supplement with group captive only if you have spare capital and predictable demand. Above ₹40 lakh a month, group captive becomes the dominant structure because the CSS savings alone, typically ₹50 lakh to ₹2 crore per year, comfortably justify the SPV setup costs and annual compliance overhead. The IPP route is the rarest in practice: it’s used by consumers who specifically want zero balance-sheet exposure and are happy to pay a 15 to 20% premium over group captive for that purity. Most listed Indian manufacturers don’t choose it; the savings difference is too large to ignore.

State-Wise Open Access Charge Exemptions

Each SERC sets its own open access framework, which means group captive economics vary state to state. Exemption from CSS for captive use comes from the Electricity Act, but wheeling, additional surcharge, and banking treatment differ, so check each state’s current orders.

State (Regulator)	CSS waiver under group captive	Wheeling charge	Banking allowance	Notes
Gujarat (GERC)	Yes, while captive status is proved	As per GERC order	₹1.50/unit (demand-based) or ₹1.10/unit (MSME and others) under the 2021 policy	Active group captive market
Maharashtra (MERC)	Yes, while captive status is proved	As per MERC order	As per MERC regulations	High CSS savings
Tamil Nadu (TNERC)	Yes, while captive status is proved	As per TNERC order	As per TNERC regulations	Strong industrial pipeline
Karnataka (KERC)	Yes, while captive status is proved	As per KERC order	As per KERC regulations	Bengaluru IT parks
Madhya Pradesh (MPERC)	Yes, while captive status is proved	As per MPERC order	As per MPERC regulations	Thinner member pipelines
Rajasthan (RERC)	Yes, while captive status is proved	As per RERC order	As per RERC regulations	Strong irradiance, growing pipeline
Andhra Pradesh (APERC)	Yes, while captive status is proved	As per APERC order	As per APERC regulations	Check for disputes on captive status

Tariff orders are revised annually; check the current wheeling and banking figures for your state before modelling. For the master regulatory reference, the Central Electricity Regulatory Commission publishes the model regulations, while each SERC issues state-specific tariff orders, MERC and MNRE publish state-wise summaries used by most developers.

Gujarat remains the deepest market. GERC’s open access regulations are stable, land conversion timelines are reasonable, and the state’s industrial belt, Ahmedabad, Surat, Vadodara, Rajkot, generates enough demand to anchor multi-member parks; for the broader state incentive landscape beyond open access, see our Gujarat solar policy overview. Maharashtra can offer high savings because CSS there is significant; model a Pune textile cluster against the current MSEDCL tariff and MERC orders.

Tamil Nadu has a mature open access market. Coimbatore textile mills and Hosur engineering plants are the dominant offtakers. Karnataka suits the IT and data-centre segment; check KERC’s current banking rules against Bengaluru’s evening peak. Madhya Pradesh can offer competitive landed tariffs, but member pipelines are thinner, finding three or four well-rated anchors takes longer.

The state-wise picture is fluid. Tariff orders are typically issued in March-April; any group captive feasibility done in February must be re-run against the new order before equity is committed.

Common Mistakes Setting Up Group Captive

Five mistakes we see repeatedly, each one preventable in feasibility, painful to fix after commissioning.

1. 1
   Over-sizing the park relative to member demand. If members hold equity but cannot absorb 51% of generation in proportion to their shares in a given year, the supply is treated as third-party sale and CSS becomes payable for that year. Size at 90 to 95% of total member demand, not 110%.
2. 2
   Weak shareholder agreement on exit and dilution. If a member sells out and captive users' combined holding falls below 26%, or shareholding stops matching offtake, the SPV loses captive status. Lock pre-emption rights and minimum holding clauses in the SHA from day one.
3. 3
   Ignoring banking charge erosion. Banking charges, in kind or per unit depending on the state, silently lift landed cost. Build them into the feasibility tariff, not the headline tariff.
4. 4
   Mis-reading [accelerated depreciation](/glossary/accelerated-depreciation). In a group captive SPV, the SPV owns the plant, so the SPV claims AD, not the members. Members benefit indirectly, through the SPV's lower tax and the tariff it can offer. Model this in the SPV's financials, not on members' books.
5. 5
   Skipping annual compliance filings. The shareholding and consumption affidavit and supporting documents must be filed every year. Failing to prove captive status means the supply is treated as third-party sale, with CSS and Additional Surcharge demanded.

For a member-side view of project economics, our solar ROI calculator guide walks through the IRR math that group captive members should run before signing the SHA.

Two more mistakes that don’t make the numbered list but cost members money every year. First, under-budgeting transmission losses. Power evacuated from a 25 MW park to a textile mill 80 km away loses 4 to 6% in transmission. If your feasibility tariff assumes a “delivered” generation figure, those losses are silently absorbed by the SPV; if it assumes generation at the busbar, the consumer absorbs them. Make sure the PPA and the financial model match.

Second, weak EPC performance guarantees. Group captive parks live or die on the Performance Ratio (PR) of the EPC build, a 78% PR vs a 75% PR delta on a 20 MW park is worth ₹2 crore a year. Lock the PR target at ≥77% in the EPC contract, with liquidated damages for underperformance, and tie a portion of the EPC payment to the first three years of generation data.

Group Captive vs Direct OPEX/PPA

For mid-sized consumers, those with 10 to 50 million kWh annual demand and no land of their own, the real choice is between joining a group captive SPV and signing an OPEX rooftop PPA. Here’s the honest balance.

Verdict. Group captive is the strongest structure for industrial consumers spending ₹40 lakh+ a month on electricity, with stable demand, in a high-CSS state (Maharashtra, Karnataka, Gujarat). It is the wrong structure for small or volatile loads, those should stick to rooftop OPEX, which removes the 51% consumption risk and the compliance overhead. The break-even is roughly 8 to 10 million kWh annual demand; below that, the equity cost rarely justifies the savings.

For factories sitting in this break-even zone, our commercial solar page maps the OPEX rooftop alternative, and the industrial solar page covers blended structures combining rooftop and group captive shares.

The blended structure deserves a separate mention. A textile mill with 40,000 sqm of usable roof and 18 million kWh of annual demand can put 4 MW of rooftop solar (CAPEX or OPEX) on its own building, covering ~30% of demand, and join a group captive park for the remaining 60 to 70%. The rooftop share carries no CSS and no wheeling. The group captive share carries no CSS but pays wheeling and banking charges. The blended landed tariff is typically ₹0.30 to 0.50/kWh better than pure group captive and ₹0.80 to 1.20/kWh better than pure OPEX. This is the structure most large Indian manufacturers settle on after running all the comparisons.

How Heaven Green Energy Helps Set Up Group Captive

Heaven Green Energy has structured group captive solar parks across Gujarat, Maharashtra, Tamil Nadu, Karnataka, and Madhya Pradesh for textile, ceramic, IT, and MNC consumers. We handle the full path end-to-end so the consumer’s CFO and plant teams aren’t running three separate vendors for legal, EPC, and compliance.

• Feasibility & anchor sourcing: landed-tariff modelling against your DISCOM tariff order, with member-by-member savings sheets your board can sign off on.
• SPV formation: ROC incorporation, Memorandum drafting, shareholder agreement, share-subscription documents, and open access filing.
• EPC delivery: utility-scale ground-mount construction from 5 MW to 30 MW with Tier-1 modules, central inverters, and 25-year performance guarantees.
• Banking & SLDC integration: banking arrangement with the DISCOM, SLDC scheduling registration, and metering reconciliation.
• Annual compliance: shareholding and consumption affidavits and supporting documents kept on a managed-service basis.

Explore the services that match your structure:

• Commercial Solar: rooftop and ground-mount for 100 kW–5 MW consumers.
• Industrial Solar: group captive and OPEX blends for large HT loads.
• Solar EPC Services: turnkey EPC with 25-year O&M.
• Ground-Mount Solar Park: utility-scale park design and delivery.
• Contact us: for a feasibility quote tailored to your DISCOM and demand profile.

Most engagements start with a one-page demand and DISCOM brief from the consumer, last twelve months of HT bills, plant location, sanctioned load, and an indicative growth view. Within two weeks, our deal team returns a feasibility note showing landed tariff under each structure (CAPEX rooftop, OPEX rooftop, group captive, blend) for the next twenty-five years, with sensitivity tables on tariff escalation, CSS movement, and PR variance. From there, anchor sourcing and SPV formation are the longest stretches; EPC delivery sits inside our standard 6 to 9 month construction window for ground-mount parks up to 20 MW. The CFO-facing model and the plant-facing energy plan are kept in sync throughout, a discipline we’ve found makes the board sign-off considerably faster.

Frequently Asked Questions

What is group captive solar and how does it differ from regular open access?

Group captive solar is a power-generation structure under Electricity Rules 2005 where multiple industrial consumers form a Special Purpose Vehicle (SPV) to own a solar park collectively. The consumers together must hold at least 26% of the SPV’s voting equity and together consume at least 51% of the annual generation, in proportion to their shareholding within a 10% variation. Unlike regular open access, where consumers buy power third-party and pay Cross Subsidy Surcharge, group captive consumers are exempt from CSS, cutting landed tariff by ₹1.5 to 3/kWh depending on the state.

How much equity does each consumer need to hold in a group captive SPV?

The 26% minimum applies to the captive users together, not to each one: combined, they must hold at least 26% of the SPV’s voting equity. Each member’s shareholding should match its planned offtake, because consumption must be in proportion to shareholding within a 10% variation. For a ₹98 crore, 20 MW project, a consumer taking 40% of the generation would subscribe to roughly 40% of the member equity pool, about ₹28 crore. Shareholding and consumption are verified every financial year; in Gujarat, through an affidavit filed by 31 October of the following year.

What savings can an industrial consumer expect from group captive solar in 2026?

Typical landed tariff under group captive is ₹4 to 5 per kWh, against HT industrial grid tariffs of ₹8 to 10 per kWh, net savings of ₹2 to 3 per kWh. For a textile mill consuming 14.5 million kWh annually, that translates to ₹3 to 4.5 crore of recurring savings. The savings widen in high-CSS states like Maharashtra and Karnataka, where the Cross Subsidy Surcharge alone is ₹1.5 to 2 per kWh.

How long does it take to set up a group captive solar project?

End-to-end setup runs 12 to 18 months from feasibility study to commissioning. Stage breakdown: feasibility and member anchoring (1 to 3 months), SPV formation and regulatory filings (2 to 3 months), member onboarding and Power Purchase Agreement signing (1 to 3 months), EPC award and construction (4 to 8 months), and commissioning with banking and SLDC integration (1 to 2 months). The construction window depends on park size and DISCOM evacuation readiness.

Which states are most active for group captive solar projects?

Gujarat, Maharashtra, Tamil Nadu, Karnataka, and Madhya Pradesh dominate group captive activity in 2026. Gujarat leads on volume because of GERC’s clean open access framework, low wheeling charges, and strong industrial demand. Maharashtra produces the highest CSS savings per kWh due to MERC’s tariff design. Karnataka attracts IT parks around Bengaluru. Madhya Pradesh offers the lowest absolute landed tariffs due to low wheeling charges.

What happens if a group captive member’s consumption drops below the required share?

If collective member consumption falls below 51% of annual generation in a given financial year, or a member’s consumption falls outside the 10% band around its shareholding, the supply for that year is treated as third-party sale and CSS and Additional Surcharge become payable. This is the single largest risk in the structure. Heaven Green sizes parks at 90 to 95% of total member demand and writes minimum-offtake covenants into the Power Purchase Agreement to manage this risk.

Can a single consumer claim accelerated depreciation in a group captive structure?

No. Depreciation under Section 32 of the Income Tax Act is claimed by the owner of the asset, and in a group captive structure that is the SPV, not its members. The SPV claims the 40% AD, which lowers its tax and its cost of power; members benefit indirectly through the tariff and the value of their shares. A consumer who wants to claim AD directly needs to own the plant itself, for example a rooftop system on the CAPEX route.

Is group captive better than rooftop OPEX for industrial consumers?

It depends on demand size and balance-sheet position. For consumers with annual demand above 8 to 10 million kWh, stable consumption, and the equity headroom to fund their share of the SPV, group captive delivers a lower landed tariff and gives upside exposure to rising grid rates. For smaller or volatile loads, rooftop OPEX is the better fit, no equity, no 51% consumption risk, and no annual SERC compliance. Many of our clients run a blend: rooftop OPEX on factory roofs plus group captive equity for the residual baseload.