Solar Irradiance Calculator
Estimate solar irradiance for your city and what it means for panel output.
About the Solar Irradiance Calculator
The Solar Irradiance Calculator gives you a clear, instant answer to a question that usually means digging through tables or guessing — enter your numbers and read the result straight away.
How much electricity will your solar system actually produce? The answer depends on the system size and the sun hours at your location. This Solar Irradiance Calculator estimates the monthly and annual energy production of a solar system in Pakistan.
The calculation multiplies the system size (kW) by the peak sun hours at your location and applies realistic system losses (inverter, wiring, temperature, soiling) to arrive at usable generation.
Peak sun hours vary across Pakistan: the south and Balochistan see more sun than the northern and western regions. Using your city's actual sun hours rather than a national average makes the estimate accurate.
Compare the estimated generation with your monthly consumption: if generation covers consumption, the system pays for itself through the bill savings — and with net metering, surplus generation earns credit.
Use the Solar Irradiance Calculator as often as you like — it is free, needs no account, and pairs well with the other calculators in this category for a fuller picture.
How to estimate solar production
- 1
Enter your system size in kW.
- 2
Enter the peak sun hours for your city (4.5–6 typical in Pakistan).
- 3
Adjust the system efficiency if you know your hardware's ratings.
- 4
Read the monthly and annual production in kWh, updated live.
Frequently Asked Questions
What is solar irradiance?
Irradiance is the solar power received per square metre. Pakistan's 4.7–5.9 peak sun hours correspond to 4,700–5,900 Wh/m² per day — among the best in the world.
How many units does a 10 kW solar system produce in Pakistan?
With ~5 peak sun hours and typical losses, a 10 kW system generates roughly 1,200–1,400 kWh (units) per month — often enough to cover a large household's full bill.
Why is actual production lower than rated?
Real-world losses — inverter conversion (~5%), wiring (~2%), temperature derating, dust and soiling — typically reduce output by 15–25% from the theoretical maximum.