Commercial Solar Power: ROI, Tax Benefits & Accelerated Depreciation Explained

For Indian businesses, rooftop solar has stopped being a green initiative and become a balance-sheet decision. Commercial tariffs of ₹8–₹13 per unit, a 40% accelerated depreciation benefit in the first year, and 18% GST input credit together push payback periods to 3–4 years, with another 21+ years of free generation after that.

Why commercial solar pays back faster than residential

Commercial users pay much higher per-unit tariffs than households. A factory paying ₹10/unit saves twice as much as a home paying ₹5/unit on every solar unit generated. Combined with tax benefits available only to businesses, the economics flip dramatically in favour of commercial.

The three financial benefits stacked together

1. Accelerated depreciation (40%)

Under Section 32 of the Income Tax Act, businesses can depreciate solar assets at 40% in the first year (down from 80% pre-2017, but still excellent). For a ₹50 lakh solar plant, this saves ₹6+ lakh in taxes in year one alone, depending on your tax bracket.

2. 18% GST input credit

The 18% GST paid on solar equipment is fully recoverable as input tax credit if you are GST-registered. On a ₹50 lakh project, that's roughly ₹7.6 lakh in recoverable taxes.

3. Lower per-unit electricity cost

Solar generation cost over 25 years works out to ₹2.5–₹3.5 per unit, against ₹10+ paid to the grid. The delta is pure cost saving against the P&L.

CAPEX vs OPEX (PPA) models

• CAPEX: you fund the plant upfront, claim depreciation and GST input, own the plant outright. Best ROI but needs upfront capital.
• OPEX (PPA): a third party installs the plant on your roof and sells you electricity at a fixed lower-than-grid rate (₹4–₹6/unit) for 20–25 years. Zero capex from your side, but you don't get tax benefits.

Most growing SMEs in India choose CAPEX because the post-tax IRR typically exceeds 25%.

Real ROI example: 100 kW factory installation

• System cost: ₹45 lakh
• Annual generation: 1,40,000 units
• Annual savings at ₹10/unit: ₹14 lakh
• Year-1 tax savings (depreciation + GST): ₹14 lakh
• Effective net cost after Year 1: ₹17 lakh
• Simple payback: ~1.2 years post tax

Numbers vary by state, tariff slab, and tax bracket — but the directional story holds for almost every Indian SME and manufacturer.

Beyond money: brand and compliance

• BRSR & ESG reporting: solar adoption directly improves your sustainability score for top-500 listed entities.
• Renewable Purchase Obligation (RPO): helps DISCOM-connected commercial users meet RPO targets.
• Customer perception: bigger buyers (especially MNCs and exporters) increasingly prefer suppliers with renewable footprints.

If you run a factory, warehouse, hotel, school, or hospital, request a commercial solar feasibility report from Siyag Group with your last 12 months of electricity bills.