Solar Tax Benefits for Indian Factories: Accelerated Depreciation, GST & ITC Guide 2026

TL;DR — Solar Tax Benefits for Indian Industrial Buyers

• Accelerated Depreciation (AD) under Section 32 of the Income Tax Act allows 40% depreciation in Year 1 on the written-down value of solar power assets. For a ₹3.5 Cr / 1 MW plant, that's a ₹1.4 Cr deduction — saving approximately ₹42 lakh in tax at the 30% corporate rate — effectively cutting your net capex by 12%.
• GST Input Tax Credit (ITC) is blocked for most captive rooftop solar plants. Per the Rajasthan AAAR ruling (June 2026) and Section 17(5)(c)/(d) of the CGST Act, electricity is an exempt supply — so ITC on solar inputs, capital goods, and services is disallowed.
• Because ITC is blocked, GST sits inside your depreciable base — increasing your Section 32 deduction by approximately 12% of the pre-tax equipment cost. This partially offsets the ITC loss.
• The 40% rate applies only if the plant is put to use for at least 180 days in the financial year. Commission before October to get the full 40%; after October, only 20%.
• AD is available to companies, LLPs, partnership firms, and sole proprietors with business income. Salaried individuals and presumptive-taxation filers (Section 44AD/44ADA) cannot claim AD.
• The effective net capex after AD for a 1 MW plant drops from ₹3.5 Cr to approximately ₹3.08 Cr — improving IRR from 23% to approximately 27% and shortening payback from 3.8 to 3.2 years.

Why Tax Treatment Makes or Breaks Solar ROI

Most Indian factory owners evaluating solar focus on the electricity bill savings — and that's the right starting point. But the difference between a good solar investment and a great one comes down to tax planning.

Here's what most solar EPC companies won't tell you: the tax benefit from accelerated depreciation alone can be worth 12–14% of your total project cost in Year 1. Combined with the energy savings, a well-structured solar investment can return your entire capex within 3 years — and then produce free electricity for the next 22.

This guide covers everything an Indian industrial buyer needs to know about solar taxation in 2026: depreciation, GST, MAT, capitalisation rules, timing strategy, and documentation — all with real numbers and practical advice.

Accelerated Depreciation — The 40% Rule

The Legal Basis

Three documents form the chain:

The rate was 80% until AY 2017-18; the Finance Act 2017 reduced it to 40%, where it remains through 2026 (unchanged in the Finance Act 2026).

How the Math Works

For a ₹3.5 Cr / 1 MW industrial rooftop solar plant:

After Year 5, the remaining ₹27.2 lakh continues depreciating at 15% WDV until negligible.

Tax saving at 30% corporate rate (common for Indian manufacturing companies):

• Year 1: ₹1.40 Cr × 30% = ₹42 lakh saved
• Year 2: ₹84 L × 30% = ₹25.2 lakh saved
• Cumulative Years 1–5: ₹3.23 Cr × 30% = ₹96.8 lakh saved

This effectively reduces the ₹3.5 Cr capex to a net ₹2.53 Cr — a 28% effective discount from the government.

What Assets Qualify for 40% AD

Key principle: The 40% rate applies to the integrated solar power generating system — modules, inverters, structures, dedicated transformer, and related electrical BOS. Civil works, office equipment, and general-purpose assets use their standard rates.

Eligibility — Who Can Claim AD?

Eligible entities (must file under "Profits and Gains of Business or Profession"):

• Private Limited Companies and Public Limited Companies
• Limited Liability Partnerships (LLPs)
• Partnership firms with business income
• Sole proprietors running a business
• Professionals with professional income (doctors, lawyers, architects, CAs)

Not eligible:

• Salaried individuals (even if they own a rooftop solar plant — AD cannot be claimed against salary income)
• Entities filing under presumptive taxation (Section 44AD/44ADA)
• Residential installations used purely for personal consumption

Important: If a salaried individual invests via a company or LLP that owns the solar plant, the entity can claim AD (reducing corporate tax), and the individual benefits indirectly through profit distribution or dividends.

The 180-Day Rule — Timing Matters

If the solar plant is put to use for less than 180 days in the financial year, only half the depreciation rate (20% instead of 40%) can be claimed in that year.

Practical implication: Commission your plant before October 1 (i.e., before the halfway mark of the financial year) to claim the full 40% in that assessment year. A plant commissioned in, say, December gets only 20% Year 1 — costing you approximately ₹21 lakh in foregone Year-1 tax savings on a 1 MW plant.

Plan your EPC schedule accordingly. A 90–120 day project started by May–June comfortably meets the September deadline.

GST on Solar Equipment — The Current Landscape (2026)

GST Rates by Component

On a typical 1 MW plant costing ₹3.5 Cr ex-GST, the weighted-average GST is approximately 12–13% — adding ₹42–45 lakh to the invoice.

Input Tax Credit — The Critical 2026 Update

For most captive industrial rooftop solar plants, ITC is blocked. Here's why:

The Rajasthan Appellate Authority for Advance Ruling (AAAR) ruled in June 2026 that:

1. Electricity generated by a solar plant is an exempt supply under GST (nil-rated per Notification 02/2017)
2. Input supplies used for establishing the solar plant are attributable to that exempt supply
3. Therefore, ITC on inputs, capital goods, and input services is blocked under Section 17(5)(c) and 17(5)(d) of the CGST Act

What this means for your factory: You cannot reclaim the 12–13% GST you pay on solar equipment if the electricity is used for captive consumption in your manufacturing business — which is the standard C&I rooftop use case.

The Silver Lining: GST Boosts Your Depreciation Base

Because ITC is blocked, the GST you pay becomes part of the asset's actual cost under Section 43(1) of the Income Tax Act. This means your 40% AD applies to the GST-inclusive cost:

• Equipment cost (ex-GST): ₹3.50 Cr
• GST paid (12% avg): ₹0.42 Cr
• Total depreciable base: ₹3.92 Cr
• Year 1 AD at 40%: ₹1.57 Cr (vs ₹1.40 Cr ex-GST)
• Additional Year-1 tax saving: ₹5 lakh

This partially — though not fully — offsets the ITC blockage. Your effective tax benefit is still strong; it's just delivered through depreciation rather than input credit.

When ITC IS Available

ITC may be available in specific scenarios:

1. RESCO/OPEX model: The developer owns the plant and sells electricity under a PPA — the developer's business IS power generation, and they may be eligible for ITC on their inputs. As the buyer, you simply expense PPA payments.
2. Open access power sale: If you generate solar power and sell it to a DISCOM or third party (taxable supply), ITC eligibility may differ — consult a GST specialist.
3. Captive power for taxable manufacturing with output GST liability: Some interpretations allow ITC when the solar plant powers a factory producing GST-taxable goods. This is a grey area post the Rajasthan AAAR ruling. Get a written opinion from your tax advisor before claiming.

Never claim both ITC and include GST in your depreciable base — this is dual benefit and will be reversed at audit.

MAT (Minimum Alternate Tax) Considerations

For companies, the Minimum Alternate Tax applies at 15% of book profits (plus surcharge and cess). Here's how it interacts with AD:

• AD reduces taxable income under the Income Tax Act, but depreciation for MAT purposes follows the Companies Act rate (typically 5.28% for solar, based on a 25-year useful life with 5% residual value).
• This creates a timing difference: your tax depreciation (40%) is much higher than book depreciation (~5.3%), so you pay MAT in the early years.
• The MAT credit can be carried forward for 15 years and set off against future regular tax liability — so the AD benefit is not lost; it's partially deferred.

Practical impact: A company in the 30% tax bracket claiming AD on a ₹3.5 Cr plant will save ₹42 lakh in Year 1 under normal provisions, but may pay ~₹21 lakh in MAT. The MAT credit of ~₹21 lakh is carried forward and can be utilised in subsequent years. Net-net, the full AD benefit is realised — just spread across Years 1–15 rather than concentrated in Years 1–5.

For LLPs, partnership firms, and sole proprietorships, MAT does not apply — the full AD benefit flows through immediately.

Capitalisation — What Goes Into the Asset Base

When capitalising your solar plant for tax purposes, include:

1. Modules, inverters, and mounting structures (ex-factory cost)
2. Cables, switchgear, junction boxes, combiner boxes
3. Transformer (if dedicated to the solar plant)
4. SCADA and monitoring equipment
5. Civil works (foundations, trenches, cable trays — at 10% rate)
6. Freight, insurance, and logistics for equipment delivery
7. Commissioning charges, professional fees, and third-party inspection
8. GST paid on all of the above (since ITC is blocked)
9. Interest on pre-commissioning borrowing (if applicable, under AS-10 / Ind AS-16)

Do NOT include in the depreciable base:

• Land cost (land is not depreciable)
• Post-commissioning O&M expenses (these are revenue expenditure)
• Staff salaries (revenue expenditure, unless directly attributable to construction)
• General administrative overheads

Financial Planning — How to Structure for Maximum Tax Benefit

Scenario 1: CAPEX Model, Corporate Buyer

Best for: Manufacturing companies with strong taxable profits and the ability to absorb AD deductions.

• Structure: Company owns the plant. Claims 40% Year-1 AD under Section 32.
• GST: ITC blocked; GST added to depreciable base.
• MAT: Pay MAT in early years; carry forward MAT credit.
• Net capex reduction: ~12% in Year 1, ~28% over 5 years (via AD).
• Best commissioning window: April–September for full 40% in that FY.

Scenario 2: CAPEX Model, LLP / Partnership / Sole Proprietor

Best for: Partnership firms, family-owned manufacturing businesses, professional firms.

• Structure: Entity owns the plant. Claims 40% AD.
• GST: ITC blocked; GST added to depreciable base.
• MAT: Not applicable — full AD benefit in Year 1.
• Net capex reduction: Same as corporate, but without MAT deferral.
• Caveat: Sole proprietors cannot separate solar ownership from personal assets — ensure clear documentation of business use.

Scenario 3: RESCO/OPEX — Delegate Tax to the Developer

Best for: Buyers without sufficient taxable income to absorb AD, or buyers preferring simplicity.

• Structure: RESCO developer owns the plant. Buyer pays ₹4.40–5.20/kWh under PPA.
• Tax: Buyer simply expenses PPA payments as revenue expenditure — reducing P&L electricity costs.
• GST: Developer handles GST and ITC on their side.
• AD: Not claimed by buyer; developer claims if eligible.

Scenario 4: Group Captive — 26% Equity + AD

Best for: Industrial estate clusters, multi-entity groups.

• Structure: Each consumer holds 26% equity in a shared solar SPV/plant.
• Tax: The SPV claims AD. Consumers expense PPA payments.
• GST: More complex; consult a specialist.
• Key advantage: Nil cross-subsidy surcharge on group captive power.

Documentation Checklist for Tax Filing

Before filing your return, ensure you have:

Common Tax Mistakes (and How to Avoid Them)

Mistake 1: Claiming Both ITC and AD on the Same GST Amount

What happens: You claim GST ITC on solar equipment AND include GST in your depreciable base. This is dual benefit — the tax department will reverse it in scrutiny assessment, with interest and penalty.

Fix: Pick one. For captive C&I solar, ITC is typically unavailable, so include GST in depreciable base and document the ITC disallowance.

Mistake 2: Missing the 180-Day Cutoff

What happens: Plant commissioned in December — you claim 40% AD instead of 20%. The excess 20% is disallowed, with interest.

Fix: Track the exact commissioning date. If less than 180 days, claim 20% Year 1. The remaining 20% catches up in Year 2.

Mistake 3: Claiming AD on Residential Rooftop

What happens: A factory owner installs solar on their farmhouse and claims 40% AD as business depreciation. This is disallowed because the asset is not used for business.

Fix: Install solar at business premises only. If you want AD, the factory roof is the right place.

Mistake 4: Not Capitalising All Eligible Costs

What happens: Only module and inverter costs are capitalised. Freight, commissioning, professional fees are expensed — losing AD on those amounts.

Fix: Capitalise the full installed cost: equipment + freight + commissioning + professional fees + pre-commissioning interest. Every rupee capitalised earns 40% Year-1 AD.

Mistake 5: Ignoring MAT Credit Carry-Forward

What happens: Company pays MAT in Year 1, records it as an expense, and forgets to track the MAT credit for future utilisation.

Fix: Maintain a MAT credit ledger. The credit is valid for 15 years. Set calendar reminders to utilise it against regular tax liability in profitable years.

Frequently Asked Questions

Can a salaried individual claim accelerated depreciation on rooftop solar?

No. AD under Section 32 is a business deduction — it can only be claimed against "Profits and Gains of Business or Profession." A salaried individual cannot claim AD against salary income, even if they own a rooftop solar plant. The workaround: invest via a company or LLP, which can claim AD and distribute benefits as dividends.

What is the GST rate on solar panels in India in 2026?

Solar PV modules and panels attract 12% GST. Solar inverters also attract 12% GST. This rate was raised from 5% by the GST Council in 2022 and remains at 12% through 2026.

Can I claim GST input tax credit on my factory's solar plant?

For most captive industrial rooftop solar plants, ITC is blocked. Per the Rajasthan AAAR ruling (June 2026), electricity is an exempt supply under GST, so ITC on solar inputs, capital goods, and services is disallowed under Section 17(5)(c)/(d) of the CGST Act. Exceptions may apply for power-generation businesses and RESCO developers — consult your tax advisor.

If GST ITC is blocked, do I lose the GST amount entirely?

Not entirely. Since ITC is blocked, the GST you paid becomes part of the asset's actual cost for depreciation purposes. Your 40% AD applies to the GST-inclusive cost — recovering approximately 40% of the GST amount through depreciation over the asset's life. It's not as good as full ITC, but it's better than losing it completely.

Does accelerated depreciation apply to used or refurbished solar panels?

No. Section 32 AD applies only to new solar equipment. Used or refurbished modules, inverters, or structures do not qualify for the 40% rate — they depreciate at standard rates (15% WDV for plant and machinery).

What happens if I sell my factory before the solar plant is fully depreciated?

If you sell the solar plant (or the factory containing it), the sale proceeds are compared against the written-down value. If sale value exceeds WDV, the excess is taxable as balancing charge (short-term capital gain under Section 50). If sale value is less than WDV, the shortfall is a terminal depreciation deduction. Plan exit strategy accordingly.

Is accelerated depreciation available under the new tax regime (Section 115BAC)?

No. Entities opting for the concessional tax regime under Section 115BAC (25.17% for domestic manufacturing companies) cannot claim accelerated depreciation. The concessional rate and AD are mutually exclusive. Run the numbers both ways — for many industrial solar buyers, the standard 30% rate + AD delivers better after-tax returns than the concessional 25.17% without AD.

Should I commission before or after September?

Before September (at least 180 days of use in the FY) to claim the full 40% in Year 1. Commissioning after September halves the Year-1 rate to 20%. For a ₹3.5 Cr plant, that's approximately ₹21 lakh in deferred tax savings. Start your EPC project by May–June to comfortably meet the September deadline.

How does accelerated depreciation affect solar IRR?

AD significantly improves project IRR by front-loading tax savings. A 1 MW plant with 23% baseline IRR (energy savings only) improves to approximately 27% IRR when AD is factored in. Payback shortens from ~3.8 years to ~3.2 years at the 30% tax rate. See our solar panel ROI payback period guide for the full calculation methodology.

Can I claim AD on a solar plant that hasn't been commissioned yet?

No. AD is available only from the year the plant is put to use (i.e., commissioned and generating). Pre-commissioning costs are capitalised as capital work-in-progress (CWIP) — no depreciation on CWIP. AD begins from the assessment year in which commissioning occurs.

Sources

• Section 32, Income Tax Act, 1961 — incometaxindia.gov.in
• Depreciation Rates, Income Tax Act (as amended by Finance Act 2026)
• Heaven Green Energy — Accelerated Depreciation on Solar 2026 Guide
• Wattency — Solar Tax & Policy Guide India 2026
• GreenTax India — Complete Guide to 40% Solar Depreciation (Section 32)
• TaxGuru — No ITC on Solar Plant Costs: AAAR Rajasthan, June 2026
• Central Board of Direct Taxes (CBDT) — Circulars and Notifications
• GST Council — Rate Notifications (Notification 02/2017-CT(Rate) and amendments)

Sun Wave Technologies — Industrial & commercial solar EPC. Faridabad HQ. 50+ MW commissioned across Delhi-NCR, Haryana, Rajasthan, UP, and Gujarat.