Your roof isn't what caps your solar size. Your BESCOM sanctioned load is.

Most quotes size your system to your roof. BESCOM sizes it to your connection.

Ask most installers how big a system you can put on your roof, and they'll measure shadow-free area and stop there. But BESCOM won't approve a net-metered rooftop system larger than your sanctioned load — the contracted capacity on your electricity connection, not the capacity your roof could physically hold. For a lot of Bengaluru homes, especially older ones, that number is smaller than homeowners expect, and it quietly caps the solar conversation before roof space ever comes up. The mismatch usually surfaces late — after a site visit, sometimes after a quote — and it changes what you can actually get approved, not just what you'd like to buy.

What sanctioned load is, and why yours is probably smaller than you think.

Sanctioned load (also called contracted load) is the maximum demand BESCOM has agreed to supply to your connection, fixed when it was first set up or last revised. Many older Bengaluru homes — sanctioned 10, 15, even 20 years ago before ACs, geysers, and induction stoves were standard — carry just 2–3 kW on a single-phase connection. Under BESCOM's rooftop rules, your net-metered system capacity is generally capped at that figure, not at whatever your roof or budget allows. A homeowner with a 2 kW sanctioned load and a roof that could easily carry 6 kW will typically find their approval capped well short of 6 kW, unless the connection itself is upgraded first.

Your sanctioned load	What it usually means for solar approval
2–3 kW (common on older single-phase homes)	System capacity typically capped near this range — a load enhancement is usually needed for anything larger.
5 kW (newer single-phase homes, revised connections)	Comfortably covers most standard residential system sizes without any extra paperwork.
Three-phase connections	Higher ceiling, but still capped at the sanctioned figure on file — worth confirming before you shortlist a system size.

The part most quotes skip: raising your sanctioned load isn't free, and it isn't a one-time cost.

If your sanctioned load won't cover the system you want, BESCOM lets you apply for a load enhancement — a separate application, with its own paperwork and processing time, before your solar connection can go through at the larger size. That part is usually explained. What's rarely explained is what happens after: BESCOM's fixed charge is billed per kW of sanctioned load, roughly ₹120/kW every month, whether you consume that capacity or not. Enhance from 2 kW to 6 kW to fit a bigger system, and you've added several hundred rupees to your fixed monthly charge — permanently, starting immediately, regardless of what your panels generate.

That's worth weighing against the actual benefit. If the larger system is sized for load you already have — a second AC, a water heater running daily — the enhancement pays for itself through higher solar offset. If it's sized for load you're hoping to add later — an EV you haven't bought, a renovation that isn't planned — you're paying the higher fixed charge now for a benefit that starts later, if it starts at all.

How to check where you stand before you shortlist a system size

• Find your sanctioned load on any recent BESCOM bill — it's listed alongside your meter and tariff category, usually near the top.
• Compare it to the system size your installer is quoting. If the quote exceeds your sanctioned load, ask directly whether a load enhancement is required and who's filing it.
• Ask for the enhanced fixed charge in rupees, not just the enhancement fee — the one-time paperwork cost is trivial next to the new monthly fixed charge you'll carry for as long as the connection stands.
• Size for load you have, not load you're hoping for, unless the extra fixed charge is small enough that future-proofing genuinely makes sense for your household.

A homeowner in Malleshwaram we advised had exactly this gap: a 2 kW sanctioned load from a connection set up in the early 2000s, and a quote for a 5 kW system aimed at an EV the family was considering buying in a year or two. Enhancing to 5 kW added roughly ₹360 a month in fixed charges, starting immediately, well before any EV arrived. We resized the system to 3 kW, matched to current usage, and left the enhancement as a deliberate future step once the EV was actually on order — not a cost carried for months against a benefit that hadn't started.