Industrial Solar in West Bengal & Kolkata: 2026 Guide

The short answer

West Bengal industrial consumers on WBSEDCL pay roughly ₹5.30–7.95 per kWh depending on voltage, slab and time of day, while CESC tariffs in Kolkata and much of Howrah run higher — which makes rooftop solar one of the strongest cost levers available to factories in the state. Under the WBERC Prosumer Regulations, 2025 (effective 31 July 2025), net metering is available up to 500 kW or sanctioned load (whichever is lower), with net billing and gross metering options beyond.

TL;DR: Industrial power in West Bengal costs ₹5.30–7.95/kWh on WBSEDCL and more under CESC, so solar displacing daytime grid units saves immediately. Net metering is capped at 500 kW or sanctioned load, whichever is lower; WBERC set FY26 feed-in tariffs of ₹3.73–4.80/kWh for net billing and gross metering by licensee and voltage. Expect 3–5 year paybacks for well-sized C&I rooftops, strongest in CESC areas.

Why West Bengal industrial tariffs make solar work

West Bengal has four main distribution licensees: WBSEDCL (state-wide), CESC (Kolkata and much of Howrah), India Power Corporation (IPCL, Asansol–Durgapur belt) and DVC (industrial command areas). Energy charges for industrial and commercial consumers broadly fall in these ranges (FY 2025-26 tariff framework):

Two things follow for a factory owner in Howrah, Dankuni, Sankrail, Haldia, Durgapur, Kharagpur or the Kolkata fringe:

1. Daytime self-consumption is the prize. A rooftop plant running alongside a daytime industrial load avoids grid units at the industrial tariff — not at the much lower export/feed-in rate. Design the plant to match load, not roof capacity.
2. CESC-area units save the most. Kolkata city and much of Howrah sit under CESC, where retail tariffs are higher than WBSEDCL's. The same kW of solar is worth more per unit there.

If your plant also carries demand charges and pays fixed/demand charges on sanctioned kVA, size the solar against the energy component first. Solar offsets roughly 30–60% of the total bill on a typical industrial site (the energy portion up to ~70%); demand charges remain unless you also manage peak demand.

The WBERC prosumer framework: net metering, net billing, gross metering

The WBERC (Grid Interactive Rooftop Solar PV System for Prosumers) Regulations, 2025, published in the Kolkata Gazette with effect from 31 July 2025, is the operative rulebook. The essentials:

• Three settlement models. Net metering (bidirectional meter, exported units netted against imports), net billing (imports at retail tariff, exports at a Commission-set feed-in tariff), and gross metering (all solar credited at the feed-in tariff).
• Capacity cap. Rooftop capacity is capped at 500 kW or the consumer's sanctioned load, whichever is lower. Systems up to 10 kW are auto-approved; larger systems need a technical feasibility study.
• Grid limits. Total rooftop capacity on a feeder/transformer cannot exceed 100% of its capacity; anti-islanding protection is mandatory.
• Application fees. ₹1,000 for LV/MV consumers and ₹5,000 for HV/EHV; licensees must respond within 20 days.
• Tariff validity. Once agreed between prosumer and licensee, the feed-in tariff remains valid for the 25-year life of the system.

For net billing and gross metering, WBERC's August 2025 order (SM-40/25-26) set FY26 feed-in tariffs by licensee and voltage: WBSEDCL ₹3.73 (EHV), ₹3.89 (HV) and ₹4.37/kWh (LMV); CESC ₹4.42–4.80/kWh; IPCL ₹4.19–4.36/kWh; and DVC ₹4.31/kWh at HV.

The practical read: net metering is worth the most because exports offset imports at the retail rate. If your sanctioned load caps your net-metered capacity, design for high self-consumption rather than maximum export.

Where the industrial demand sits

Sun Wave serves factories across the Kolkata–Howrah corridor and the state's industrial belts. The clusters where rooftop solar pencils out fastest:

• Howrah, Sankrail, Dankuni, Uluberia — engineering, casting and light manufacturing on the west bank; a mix of WBSEDCL and CESC supply.
• Kolkata (CESC areas) — printing, packaging, food processing, cold storage and IT parks; highest retail tariffs in the state.
• Haldia and Falta — petrochemicals, chemicals and warehousing; large shed roofs and process loads.
• Durgapur–Asansol–Raniganj — steel, refractories and coal-belt industry, partly under DVC/IPCL supply.
• Bardhaman, Kalyani, Kharagpur — food processing, engineering and institutional loads.

For a worked method on sizing before you commit, see our industrial solar feasibility study checklist and how to size a solar plant for a factory.

What a West Bengal rooftop project actually involves

A typical C&I rooftop installation follows the same statutory path as elsewhere in India, with WB-specific details:

1. Feasibility and design. Load history, roof structure, shadow analysis, and a plant size capped by the 500 kW/sanctioned-load net-metering rule.
2. Application to the licensee. Online or physical application (fee ₹1,000 LV/MV, ₹5,000 HV/EHV). Up to 10 kW is auto-accepted; above that the licensee runs a feasibility study and must respond within 20 days.
3. Electrical inspector approval. Installations above the state threshold also need the electrical inspector's (CEIG) safety approval — see our CEIG approval guide for industrial solar.
4. Metering. Net meter or bidirectional meter plus generation meter, installed and maintained by the licensee.
5. Commissioning and net-metering agreement. Once the tariff (for net billing/gross metering) is agreed, it holds for the project's 25-year life.

Payback: what to actually expect

At ₹5.30–7.95/kWh avoided cost, a well-sized industrial rooftop in West Bengal typically achieves:

• CAPEX (self-owned): payback in 3–5 years, then near-free power for the remaining life. The 40% accelerated depreciation under Section 32 materially improves year-one economics — see our solar accelerated depreciation guide.
• RESCO/zero-capex: the developer funds the plant and sells you power below the grid tariff, typically 10–30% cheaper from month one. Compare models in our CAPEX vs OPEX vs open access comparison.
• Open access / group captive becomes interesting for loads above what the roof can serve — though West Bengal's open access charges and banking rules are state-specific and should be modelled before committing.

Illustrative example (indicative, not a quote): a 500 kW rooftop on a Howrah plant generating ~7.5 lakh units a year, with 85% self-consumption against a ₹7/kWh blended tariff, displaces roughly ₹44–45 lakh of annual energy cost. Actual numbers depend on your load profile, tariff schedule and net-metered capacity — get a plant-specific estimate.

Frequently Asked Questions

What is the net metering limit for rooftop solar in West Bengal?

Net metering is permitted up to 500 kW or the consumer's sanctioned load, whichever is lower, under the WBERC Prosumer Regulations 2025. Systems up to 10 kW are approved automatically; larger systems require a feasibility study by the distribution licensee, which must respond within 20 days.

How much does industrial electricity cost in West Bengal?

WBSEDCL HT/industrial energy charges run roughly ₹5.30–7.95 per kWh for FY 2025-26 depending on voltage, consumption slab and time of day; LT industrial is around ₹6.00–7.50/kWh and commercial ₹7.50–9.00/kWh. CESC tariffs in Kolkata and parts of Howrah are higher, which strengthens the solar case there.

What is the feed-in tariff for rooftop solar in West Bengal?

WBERC's August 2025 order set FY26 feed-in tariffs for net billing and gross metering: WBSEDCL ₹3.73/kWh (EHV), ₹3.89 (HV) and ₹4.37 (LMV); CESC ₹4.42 (EHV) to ₹4.80 (LMV); IPCL ₹4.19–4.36/kWh; DVC ₹4.31/kWh at HV. Once agreed, the tariff is valid for the 25-year project life.

Is rooftop solar worth it for factories in Howrah and Kolkata?

Yes, especially where daytime load is steady. Displacing CESC-area or WBSEDCL HT units at ₹5.30–7.95/kWh (and higher under CESC) with self-generated solar typically yields a 3–5 year payback on CAPEX, with larger savings where self-consumption is high and net metering banks weekend surplus.

Does West Bengal allow third-party sale or group captive solar?

Yes, subject to West Bengal's open access framework — eligibility, cross-subsidy surcharge, wheeling and banking are set by WBERC and vary by consumer category. Because those charges change the landed cost materially, model the full open access chain against rooftop self-consumption before choosing a route.

Sources

• WBERC (Grid Interactive Rooftop Solar Photovoltaic System for Prosumers) Regulations, 2025 — effective 31 July 2025 (Kolkata Gazette), as reported by SolarQuarter, 3 September 2025.
• WBERC suo-motu order SM-40/25-26, 20 August 2025 — feed-in tariffs for net billing and gross metering under the 2025 Prosumer Regulations.
• Mercom India, 18 and 28 August 2025 — West Bengal prosumer regulations and FY26 feed-in tariff determination.
• WBSEDCL Tariff Notification / Gist of Tariff Order, FY 2025-26 (WBERC tariff order TP-98/22-23 line) — industrial and commercial energy charge ranges.
• Open Access Exchange, West Bengal electricity tariff FY 2025-26 — LT/HT industrial and commercial rate bands.

Explore Sun Wave's solar solutions

Sun Wave Technologies is a C&I solar EPC with an active West Bengal programme, serving Howrah, Kolkata, Haldia, Durgapur and the wider industrial belt with EPC/CAPEX solar, zero-capex RESCO/OPEX and open-access models — including statutory approvals, net metering and long-term O&M. If you run a factory in the Kolkata–Howrah corridor or the Asansol–Durgapur–Haldia belt, talk to our team for a load-matched rooftop assessment.