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Generation & sizing

How much will solar generate here? · Sizing: why we start from your bill, not your roof

How much will solar generate here?

On the plains of Bengal and the Bihar border, a well-designed, shadow-free, south-facing plant typically produces 3.4 to 4 units per kWp per day, averaged over a year — roughly 1,240 to 1,460 units per kWp a year.

  • Strongest months: March to May, when skies are clear and days are long.
  • Weakest months: December and January, when days are short and often hazy. July to September dip too, under monsoon cloud. We put both in the numbers.
  • Orientation matters: an east-west roof can produce around 7% less than the same plant facing south.
  • Hills differ: Sikkim and Darjeeling sites depend heavily on slope, aspect and shading. They are always simulated.
Some quotations promise 4.5 to 5 units per kWp per day. Independent satellite-based modelling for Siliguri does not support that at any tilt. We would rather under-promise — and every Solarverse proposal is backed by a 3D simulation of your actual roof.

Sizing: why we start from your bill, not your roof

  • Consumption first. Twelve months of bills tell us how many units solar can usefully replace.
  • The legal ceiling. Capacity cannot exceed your sanctioned load or contract demand.
  • Then the roof. Allow about 90–100 sq ft of shadow-free flat roof per kWp. Elevated structures keep a terrace usable; sheet roofs take modules flush.
  • Then the details. Inverter loading, string design, cable runs, walkways for cleaning and where the plant ties into your LT panel.

A plant that is sized correctly is not always the biggest plant the roof can carry. Sometimes the honest answer is a smaller one — and we will tell you.

Rather we read your bill for you?

Send it on WhatsApp. We will decode it, tell you which of these rules apply, and size a plant to it.