In short: size a solar system by the units on your electricity bill, not by marla. In Lahore, each kW of panels produces about 130 units a month on average.
A 5 marla home using around 500 to 700 units in summer usually needs about 4 to 6 kW. A 10 marla home using around 1,000 to 1,300 units usually needs about 8 to 10 kW.
For net billing you also need a three-phase connection and a sanctioned load of at least 5 kW, and at least equal to your solar size.
Last updated: 14 September 2026. Production figures are from the European Commission’s PVGIS solar calculator for Lahore. Sources are listed at the end.
Why marla alone is the wrong way to size solar
Two 10 marla houses can have completely different bills. One family might run three ACs all evening, and another might have one AC and inverter fans. What matters is how many units you use and when you use them. The plot size matters mainly for one thing: how much roof space you have for panels.
Step 1: find your monthly units
Take your highest summer bill (June to August) and your lowest winter bill from the last 12 months. The summer figure shows your peak need; the average across the year shows what a system should cover over time. You can check past bills on LESCO’s official website under “Customer Bill”.
Step 2: convert units to system size
PVGIS data for a south-facing system at a 20-degree tilt in Lahore gives about 1,570 units per kW per year, roughly 130 units per kW per month on average. It varies from about 116 units in January to about 152 units in May.
| Average monthly units | Approximate system size | Typical home |
|---|---|---|
| 300 units | About 2.5 to 3 kW | Small home, 1 AC |
| 500 units | About 4 kW | 5 marla, 1 to 2 ACs |
| 700 units | About 5.5 kW | 5 marla, 2 ACs |
| 1,000 units | About 8 kW | 10 marla, 2 to 3 ACs |
| 1,300 units | About 10 kW | 10 marla, 3 or more ACs |
The “typical home” column is a loose illustration only; your own bill is what counts. Divide your average monthly units by 130 for a starting estimate, then adjust for the next step. For bigger homes, see our guide to a solar system for a 1 kanal house.
Step 3: adjust for net billing
Under net billing, a unit you use yourself saves your full tariff, but a unit you export is credited at a much lower rate, reported at roughly Rs 8 to Rs 11 per unit when the rules started. So:
- If most of your use is in daylight (pumps, washing, work-from-home, daytime ACs), sizing close to your total units works well.
- If most of your use is in the evening, a very large on-grid system mainly adds cheap exports. Consider a slightly smaller system, moving loads to daytime, or a battery. See our guide to hybrid solar systems in Lahore.
Step 4: check your roof space
In most Lahore housing societies a marla is counted as 225 square feet, so a 5 marla plot is about 1,125 sq ft and a 10 marla plot about 2,250 sq ft. Some areas use a different marla size. Usable roof space is always smaller than the plot, because of stairs, water tanks and shade.
As a rough guide, a modern panel of about 580 to 600 watts measures about 2.3 m × 1.1 m. With spacing for mounting and cleaning:
- a 5 kW system needs about 9 panels and roughly 350 to 450 sq ft of clear, unshaded roof;
- a 10 kW system needs about 17 to 18 panels and roughly 700 to 850 sq ft.
Elevated steel structures can make better use of limited roofs; in DHA, height limits apply and DHA must approve the installation first (see solar installation in DHA Lahore). Always keep panels clear of shade from water tanks, parapet walls and neighbouring buildings.
Step 5: check net billing eligibility
- Three-phase connection, which net billing applicants need.
- Sanctioned load of at least 5 kW, and at least equal to your solar size. Many 5 marla homes have a lower sanctioned load, so check your bill. See how to check and increase sanctioned load with LESCO.
- Spare transformer capacity on your street’s transformer.
Then follow our step-by-step guide to applying for LESCO net billing in Lahore.
Frequently asked questions
What size solar system do I need for a 5 marla house?
Most 5 marla homes using around 500 to 700 units a month in summer need about 4 to 6 kW. Check your own bill: divide average monthly units by about 130.
What size solar system do I need for a 10 marla house?
Homes using around 1,000 to 1,300 units a month usually need about 8 to 10 kW, if the roof has enough unshaded space.
How much roof space does a 10 kW solar system need?
Roughly 700 to 850 square feet of clear, unshaded roof for about 17 to 18 modern panels, including spacing.
Can a 5 marla house get net billing?
Yes, if it has a three-phase connection and a sanctioned load of at least 5 kW that is not smaller than the solar system. Otherwise the load must be extended first.
How much does 10 kW net billing cost?
With Solar Net Metering, net billing for a 10 kW system costs Rs 160,000 with LESCO, or Rs 200,000 with the other distribution companies. See the full net metering cost breakdown for Lahore.
اردو خلاصہ
سولر سسٹم کا سائز مرلے سے نہیں بلکہ بجلی کے بل کے یونٹس سے طے کریں۔ لاہور میں ہر کلو واٹ سولر اوسطاً ماہانہ تقریباً 130 یونٹ بناتا ہے، اس لیے اپنے اوسط ماہانہ یونٹس کو 130 سے تقسیم کریں۔ عام طور پر 5 مرلہ گھر کے لیے تقریباً 4 سے 6 کلو واٹ اور 10 مرلہ گھر کے لیے تقریباً 8 سے 10 کلو واٹ سسٹم درکار ہوتا ہے۔ 10 کلو واٹ کے لیے تقریباً 700 سے 850 مربع فٹ بغیر سائے کی چھت چاہیے۔ نیٹ بلنگ کے لیے تھری فیز کنکشن اور کم از کم 5 کلو واٹ منظور شدہ لوڈ ضروری ہے۔
اردو میں مکمل گائیڈ: بجلی کے بل سے سولر سسٹم کا سائز کیسے نکالیں
Not sure what size you need?
Send us your LESCO bill and Solar Net Metering will suggest the right system size for your home in Lahore. Net billing for a 10 kW system with LESCO costs Rs 160,000. Office: 222 Main Boulevard, DHA Phase 6, Lahore.
Sources
- PVGIS (European Commission Joint Research Centre): Lahore, 20° tilt, south-facing, 14% losses, PVGIS-ERA5 2005–2023
- NEPRA (Prosumer) Regulations 2026, S.R.O. 251(I)/2026
- PITC Net Metering / Net Billing Portal and its installer guidelines
Sizes and roof areas are estimates for planning; a site survey confirms the right system for your home.