Rooftop Solar for Businesses: Subsidies and Payback

For most Indian businesses, the roof is an unused asset sitting above a large electricity bill — and solar has quietly become one of the highest-IRR investments available to an MSME: paybacks of 3–5 years, 25-year asset life, and a tax treatment built to accelerate adoption. The residential headlines (PM Surya Ghar's household subsidies) don't apply to companies, but the commercial case doesn't need them. Here is the honest business math and the buying playbook.

The economics, straight

• Capex: commercial rooftop systems currently run roughly ₹40,000–55,000 per kW installed (scale, structure and module choice moving the number)
• Generation: ~4 units/kW/day across most of India — a 100 kW plant produces ~1.4–1.5 lakh units annually
• Offset value: against commercial/industrial tariffs of ₹7–10/unit, that's ₹10–14 lakh a year on a ~₹45–50 lakh investment — 3.5–5 year simple payback, then two decades of near-free power
• O&M: minimal (cleaning, inverter replacement mid-life) — budget 1–2% of capex annually

The policy stack for businesses

Accelerated depreciation — the big one: solar assets enjoy 40% depreciation (WDV) under income tax, letting profitable businesses recover a large slice of capex through tax savings in the first years — this alone compresses effective payback by around a year for tax-paying firms. Net metering — export surplus to the grid for credits, per state regulations (capacity caps and banking rules vary by DISCOM; some states restrict C&I net metering sizes — verify before design). MSME-specific support — several states' industrial policies and energy-efficiency schemes offer capital subsidies or interest subvention on solar for MSMEs, and cluster programmes (with bodies like SIDBI's green financing lines — 4E schemes) finance it cheaply. GST — solar devices attract concessional rates (12% regime on the equipment composite per current structure), with ITC available for businesses. No central capex subsidy for C&I — the household 40%/₹78,000-capped subsidies are residential-only; commercial cases stand on economics, which they comfortably do.

Buying well: the checklist

• Size to your daytime load first: self-consumption beats export economics almost everywhere — analyse 12 months of bills (contract demand, ToD patterns) before capacity is chosen
• Structural audit: the roof must carry ~15 kg/sqm plus wind loads; ballast vs penetrating mounting decided by an engineer, not a salesman
• Component tiers: ALMM-listed modules (mandatory for many connections), reputed inverters with 5–10 year warranties, and performance-ratio guarantees (>75–80%) in the contract
• Paper stack: DISCOM approval/net-metering application, CEIG safety approval beyond thresholds, and insurance riders adding the plant to your fire policy
• Vendor diligence: installed-base references, O&M terms, generation guarantees with liquidated damages — the industry has both excellent EPCs and disappearing ones

Beyond the roof: open access and the future bill

Larger consumers (typically 100 kW–1 MW+ contract demand, state-wise) can source solar via open access/group captive — buying from off-site solar parks at tariffs that undercut grid power meaningfully, without using your roof at all. Charges (wheeling, cross-subsidy surcharges) vary by state and change; model with current numbers. And watch the direction of travel: ToD tariffs, green-energy obligations on larger consumers, and buyers' ESG procurement all reward early movers. A business that solarises today is hedging twenty years of tariff inflation at a known price — which is the actual investment case beneath the payback math.

How Aidwish helps

Aidwish runs solar decisions for businesses — load analysis and sizing, capex/opex model comparison, vendor and contract diligence, DISCOM/net-metering paperwork, and the depreciation/GST structuring — so the roof starts paying rent.