What is the Solar Panel Calculator?
Thinking about going solar? Enter your average monthly electricity units (from your bill), the peak sun hours in your area and the panel wattage, and this calculator estimates the system size in kW, the number of panels, roof space, suggested inverter size, monthly generation, cost and payback period.
In most of Pakistan there are 5–6 peak sun hours per day, which makes solar one of the fastest-paying home investments.
How to use the Solar Panel Calculator
- Enter your monthly units (kWh) from your electricity bill.
- Check sun hours and panel wattage (e.g. 550 W mono panels).
- Add cost per watt and your unit price to see savings and payback.
Example
400 units per month ÷ 30 = 13.3 units/day. At 5.5 sun hours and 80% efficiency: 13.3 ÷ (5.5 × 0.8) ≈ 3 kW, which is about 6 panels of 550 W.
On-grid, hybrid or off-grid?
- On-grid (net metering): cheapest, sells extra units to the grid, no backup during load-shedding.
- Hybrid: grid + batteries, gives backup.
- Off-grid: batteries only, for places without grid power.
Frequently asked questions
How many units does a 5 kW system make?
Roughly 550–700 units per month in Pakistan, depending on season and location.
How much roof space do I need?
About 2.5–3 m² per 550 W panel, plus walking space.
Is net metering worth it?
Rules and buy-back rates change – check the latest policy with your DISCO and installer.
Is this a quote?
No, it is an estimate. Get a site survey from a certified installer.
This solar panel calculator is 100% free, needs no signup and works on phones, tablets and computers. Your data is processed in your browser and never uploaded.
Last updated: · By NodifyTech