If you’re planning a rooftop solar installation in Kolkata, Howrah, or anywhere else in West Bengal, the very first decision you’ll face isn’t panel brand or wattage — it’s which type of system to install. The on-grid vs off-grid solar system question shapes everything else: your upfront cost, your subsidy eligibility, and how your home behaves during a power cut. Here’s a clear, practical breakdown to help you decide.
The Two System Types, Explained Simply
On-grid (grid-tied) solar connects directly to your local power utility’s electricity grid. Your panels power the home during the day, and any surplus flows back into the grid through net metering. At night or on cloudy days, you draw power from the grid as usual — no batteries involved. Systems like this are also what qualify for the PM Surya Ghar Yojana subsidy, which we’ve covered in detail in our guide to the West Bengal solar subsidy.
Off-grid solar disconnects entirely from the utility. All your electricity comes from panels plus a battery bank. It’s the setup you’d see on a remote farmhouse with no grid access nearby — not something most West Bengal homeowners in Kolkata or Howrah actually need, since grid coverage here is already reliable and extensive.
How Each One Performs on the Things That Matter
| Factor | On-Grid | Off-Grid |
| Upfront cost | Lower | Higher |
| Works during power cuts | No (shuts off for safety) | Yes |
| Net metering credit | Yes | No |
| PM Surya Ghar subsidy | Yes | Not eligible |
| Battery maintenance/replacement | None | Ongoing |
| Best suited for | Reliable grid areas, lower budget | Remote, no-grid locations |
One point worth flagging clearly: off-grid systems are not eligible for the PM Surya Ghar Yojana subsidy, because the scheme is built around net metering and grid integration with your power utility. If lowering your upfront cost through the subsidy matters to you — and for most homeowners, it does — that alone rules off-grid out unless you genuinely have no grid connection to begin with.
Why This Decision Looks Different in West Bengal
A few regional factors are worth weighing before you choose:
- Net metering payback. Under WBERC’s net metering regulations, exported units are settled at a set feed-in tariff against your bill, with any surplus carried into the next cycle. This only applies to on-grid systems — it’s a real, ongoing saving that off-grid homeowners simply don’t get.
- Monsoon and humidity. West Bengal sees 1,500–2,000 mm of annual rainfall, and coastal and Sundarbans-adjacent areas deal with high humidity year-round. Whichever system you choose, insist on an IP66-rated inverter and marine-grade circuit board coating — this matters more here than in drier states.
- Voltage fluctuation. Some WBSEDCL-served district towns experience grid voltage swings, so inverters rated to handle a wide voltage band (roughly 180–270V) hold up better long-term.
- Which power utility serves your area. Kolkata city runs on CESC, while most of the rest of West Bengal is served by WBSEDCL. Both currently support net metering for solar, but the application process and empanelled vendor lists differ slightly between the two — worth confirming which applies to your address before you commit to a system type.
A Simple Way to Decide
Ask yourself these two questions:
- Do you have a reliable grid connection at your address? If yes — which is true for the vast majority of homes in Kolkata and Howrah — on-grid is almost always the better choice.
- Do you want the subsidy to bring your cost down? If yes, on-grid is the way to go — off-grid doesn’t qualify for PM Surya Ghar Yojana at all, since the scheme is built around grid integration.
For nearly every home in Kolkata and Howrah, on-grid is the practical, cost-effective choice — lower upfront cost, subsidy-eligible, and backed by ongoing net metering savings. Off-grid only makes sense if you’re genuinely without grid access, which is rare in this region.
Still Not Sure Which Fits Your Home?
The right choice depends on your roof, your load pattern, and how your specific locality’s power supply actually behaves — not just general rules of thumb. As an EPC (Engineering, Procurement, and Construction) solar company, Apris Solar handles the full journey in-house — from designing the right system for your home, to sourcing the equipment, to installation — so you get one straight recommendation instead of juggling multiple vendors, no pressure either way.
📞 WhatsApp us or visit apris.in/solar-company-contact-us for a free rooftop assessment.
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