What Size Solar System Do I Need for My Pakistani Home in 2026?
A simple framework for sizing your system based on your last twelve months of bills, plus what changes under the 2026 net billing rules
By Asad Baig · Lahore · April 2026 · Approx. 5-min read
The simple framework
The right solar system size for your home depends on three numbers:
- Your average monthly electricity consumption in units (kWh)
- The proportion of that consumption that occurs during daylight hours (roughly 6 AM to 6 PM)
- Whether you want to maintain a grid connection for backup
Pull your last twelve months of electricity bills. Calculate your average monthly consumption. Estimate what proportion is daytime versus evening. With those two numbers, you can size your system within a 10-20 percent margin without consulting an engineer.
This article walks through the calculation in plain English.
Step one: Calculate your average monthly consumption
Look at your last 12 months of electricity bills. Each bill shows your "units consumed" for the billing period. Add them up. Divide by 12.
That is your average monthly consumption in units (kWh).
For most middle-class Pakistani households, this number is between 400 and 1,200 units per month. Heavy AC users in summer can hit 2,000+ units in peak months. Lower-middle-class households without AC typically consume 200-500 units.
Note that consumption varies seasonally. Summer (May to September) is typically 30-50 percent higher than winter (December to February) for households with AC. Annual average smooths this out.
Step two: Estimate your daytime versus evening usage
This is harder because most Pakistani bills do not break out daytime versus evening consumption. Estimate based on your household pattern.
Mostly daytime use (say 70-80% during daylight): Office or shop running daytime hours, school-age children at home, AC running during peak afternoon heat, kitchen during day.
Mixed use (50-50 daytime to evening): Typical residential pattern with people home in evenings, AC running into the night, evening activities (TV, fans, lights, devices charging).
Mostly evening use (60-70% post-6 PM): Office workers home only in the evening, heavy nighttime AC use, household activities concentrated after sunset.
Your daytime versus evening estimate determines whether a hybrid system with battery is right for you. Hybrid is recommended when evening use exceeds 30% of daily total.
Step three: Calculate target system size
The standard rule of thumb in Pakistan in 2026:
- System size in kW = (Monthly consumption in units) ÷ 100
So a household consuming 800 units per month should look at approximately an 8 kW system. A household consuming 1,200 units should look at approximately 12 kW.
This rule of thumb assumes you want to cover most of your daytime consumption with solar production, with surplus going to battery (in hybrid systems) or to grid export (in pure grid-tied systems).
The rule of thumb sizes for self-consumption rather than maximum export. This is the right approach under 2026 net billing, where exporting at Rs. 11/unit to buy back at Rs. 48/unit is poor economics.
| Monthly consumption | Recommended system size | Configuration |
|---|---|---|
| 200-400 units | 4-5 kW | Pure grid-tied or small hybrid |
| 400-700 units | 5-7 kW | Hybrid with 5 kWh battery |
| 700-1,000 units | 7-10 kW | Hybrid with 10 kWh battery |
| 1,000-1,500 units | 10-15 kW | Hybrid with 10-15 kWh battery |
| 1,500-2,500 units | 15-20 kW | Hybrid with 15-20 kWh battery |
| 2,500+ units | 20-25 kW | Hybrid with 20+ kWh battery |
What changed under the 2026 rules
Under 2024 net metering, the right strategy was to oversize for export. Bigger system, more revenue from grid export at parity rates, faster payback. Many 2024 installations were 50% larger than current consumption to maximise export revenue.
Under 2026 net billing, oversizing for export is poor economics. The export rate (Rs. 11) is much lower than the import rate (Rs. 48). The right approach is to size for self-consumption.
This means the system size that was right in 2024 is too large in 2026. If you are installing today, do not let an installer size you on 2024 assumptions. Insist on sizing based on your actual consumption pattern with the 2026 net billing rates assumed for export.
I have written about this at Net Metering vs Net Billing in Pakistan and Hybrid Solar Systems in Pakistan: The New Math.
THE 2026 SIZING DECISION RULE
Size for self-consumption (matching daytime use), not for maximum export. Add battery storage if you have meaningful evening usage. The system that was right in 2024 (oversized for export) is too large in 2026.
What can throw off the calculation
Three things to consider beyond the rule of thumb.
Roof area and orientation: A south-facing flat roof or south-sloped roof gets the best solar exposure in Pakistan. East and west facings get less. North gets least. Available roof area limits maximum system size regardless of consumption.
Shade: Trees, neighbouring buildings, water tanks, antennas. Solar panels lose disproportionate output when partially shaded. Walk your roof at noon to check for shade. Adjust system layout (or panel selection - microinverters tolerate partial shade better) accordingly.
Future plans: If you are planning to add an electric vehicle (consumption +200-400 units/month), an additional AC unit, or a swimming pool pump, factor these into your sizing. Going larger initially is cheaper than adding capacity later.
What you should take away
Three things.
Size your system based on your actual monthly consumption, not on rules of thumb. Pull 12 months of bills. Calculate average. Use the rule of thumb as a starting point.
Size for self-consumption in 2026, not for export. The 2024 oversize-for-export strategy no longer makes economic sense.
Add battery storage if you have meaningful evening consumption. Hybrid systems are now the right choice for households with post-6 PM usage above 30% of daily total.
For the comprehensive decision framework with three household scenarios, see my pillar on solar in Pakistan in 2026.
Now you know how to size. Pass it on.
Thank you for reading.
, Asad Baig, Lahore, April 2026
Frequently asked questions
What size solar system do I need for a typical Pakistani home? For a household consuming 500-1,000 units per month, a 5-10 kW system is appropriate. Use the rule of thumb: system size in kW equals monthly consumption in units divided by 100.
Should I oversize my solar system in 2026? No. Under the 2026 net billing rules (export at Rs. 11/unit, import at Rs. 48/unit), oversizing for export is poor economics. Size for self-consumption matching daytime use, with surplus stored in battery for evening use.
How do I estimate my daytime versus evening electricity use? Most Pakistani bills do not break out the split. Estimate based on your household pattern. If most household members are home only in the evening with AC running at night, evening use is likely above 30% (use hybrid). If household activity is mostly daytime, evening use is likely below 30% (pure grid-tied may be sufficient).
Sources and notes
- NEPRA Prosumer Regulations 2026 (nepra.org.pk)
- BloombergNEF residential solar sizing methodology
- Pakistan Solar Association installer pricing and sizing guides
- IRENA solar resource data for Pakistan
Related reading from Asad Baig
The pillar this answers under
Sibling long-tail explainers
- Should I Install Solar in Pakistan After the 2026 Rules?
- Is Solar Still Worth It in Pakistan in 2026?
- Solar With Battery vs Net Billing: Which Is Better in 2026?
- How to Calculate Solar Payback in Pakistan in 2026
Asad Baig