Once the system is installed, everyone asks the same thing: “Is it making enough?” To answer that, you need a rough idea of what to expect.
- Pakistan averages roughly 4 to 5 units per kW of panels per day across the year.
- Spring and summer are higher, winter and smoggy weeks lower.
- A 10kW system often makes around 1,200 to 1,500 units a month on average.
- Compare clear-day output month to month to spot problems early.
The basic rule of thumb
Across a year, a well-installed, south-facing system in most of Pakistan produces roughly 4 to 5 units (kWh) per kW of panels per day on average. Sunnier, less polluted areas tend toward the top of that range. Smoggy winters pull the average down.
What that means for common sizes
| Panel capacity | Per day (avg.) | Per month (avg.) |
|---|---|---|
| 3kW | 12 to 15 units | 360 to 450 |
| 5kW | 20 to 25 units | 600 to 750 |
| 10kW | 40 to 50 units | 1,200 to 1,500 |
| 15kW | 60 to 75 units | 1,800 to 2,250 |
These are averages over the year. Individual months will be above or below.
How the seasons change it
- March to May: often the best months. Strong sun, long days, not yet extreme heat.
- June to August: long days, but heat reduces panel efficiency and monsoon clouds cut some days short.
- September to October: good, steady production.
- November to January: shortest days, low sun, smog and fog. Output can drop significantly. See solar output in winter.
Why your numbers might be lower
- Panels facing east, west or north, or at a very flat angle
- Shade from tanks, walls or trees, especially in winter
- Dust and bird droppings
- Inverter clipping, when panels exceed what the inverter can take
- Battery full and nothing using the power, so the inverter throttles solar (common in off-grid setups)
- A faulty string or loose connector
The “battery full” trap
On hybrid systems without export, once the battery is full and the house isn’t using much, the inverter reduces solar output. Your app shows lower units, but the panels are fine, there was just nowhere for the power to go. That’s a sign to shift more appliances to daytime.
How to check your system
- Pick two or three clear days each month.
- Note total solar units for each.
- Divide by your panel kW to get units per kW per day.
- Compare month to month and with the ranges above.
A sudden drop on clear days usually means a fault or new shade. A slow drift down is often dust. For fault causes, see common inverter faults.
Think your system is underperforming?
Send us your panel size and a month of app data. We’ll tell you if it looks normal.
