How our solar calculator works
This free tool turns one number — your average monthly electricity bill — into a realistic
solar plan for your home in Pakistan: the system size you need in kilowatts (kW), an
approximate cost, and how much you can expect to save every month.
Behind the scenes it does what a solar engineer does on day one. It converts your bill into monthly
units (kWh) using your city's electricity tariff, then divides that by how much solar
generates in your area — in Pakistan, roughly 4 units per day for every 1 kW installed,
or about 120 units a month per kW. A little headroom is added for future load growth and normal panel
ageing, giving the recommended system size. Because generation and tariffs differ by location, the
calculator also asks for your city.
Worked example. A Karachi home with a PKR 50,000 monthly bill uses
roughly 800 units a month. Divide by ~120 units per kW and you land near a 7–8 kW
system — enough to wipe out the bulk of that bill through net metering. Enter your own bill above to see
the number for your home.
What size solar system do I need in Pakistan?
Your monthly bill is the single biggest driver of system size. These are typical starting points for
a net-metered home — the calculator refines them for your exact city and usage:
| Monthly bill (PKR) | Approx. usage | Suggested system |
|---|
| 15,000 – 25,000 | ~250–400 units | 3 – 5 kW |
| 25,000 – 45,000 | ~400–700 units | 5 – 8 kW |
| 45,000 – 80,000 | ~700–1,200 units | 8 – 12 kW |
| 80,000 + | 1,200+ units | 12 – 15 kW + |
Actual size depends on your tariff slab, roof space and appliance load. Plan for about
60–70 sq ft of shade-free roof per kW.
What the calculator asks you
Your monthly bill. Use a recent average — ideally a summer month, when cooling load and
generation both peak. This anchors the whole estimate.
Your city. This sets two things at once: local sun-hours (Karachi, Multan and interior
Sindh see more usable sun than the far north) and your distribution company's tariff — K-Electric, LESCO,
IESCO, MEPCO and the rest all bill differently. Both feed into the size and savings you see.
Your load type. Whether you want a straightforward on-grid system for savings, or a
hybrid with battery backup for load-shedding, changes the recommendation and the cost.
How much can you save?
A correctly sized, net-metered system typically offsets 80–100% of your grid bill.
Surplus power generated during the day is exported to the grid and credited against the units you draw at
night, so your meter effectively runs backwards when the sun is out. With today's high tariffs, most
homeowners see the system pay for itself in about 3–4 years — after which it keeps
producing near-free electricity for 20+ years. Bigger bills pay back fastest, because every unit you
self-generate replaces a more expensive grid unit.
When you're ready, the numbers here become a proper engineered quote after a free expert
survey of your roof — no obligation.
Frequently asked questions
How accurate is the solar calculator?
It gives a well-grounded first estimate — typically within about 10–15% of a final engineered design. It sizes your system from your average monthly bill and city, using real Pakistani generation and tariff assumptions. The exact figure is confirmed after a free expert survey that accounts for your roof, shading and appliance load.
What size solar system do I need for my home in Pakistan?
As a rule of thumb: a PKR 15,000–25,000 monthly bill usually needs a 3–5 kW system, PKR 25,000–45,000 needs 5–8 kW, PKR 45,000–80,000 needs 8–12 kW, and above PKR 80,000 needs 12–15 kW or more. Enter your bill above for a figure tailored to your city and usage.
How is my system size calculated from my electricity bill?
The calculator converts your bill into monthly units (kWh) using your city's tariff slab, then divides by how much a solar system generates locally — in Pakistan roughly 4 units per day per kW, or about 120 units a month per kW. A little headroom is added for future load and panel degradation to give the recommended size in kW.
How much can I save with solar in Pakistan?
A correctly sized, net-metered system typically offsets 80–100% of your grid bill, so most homeowners save the large majority of what they currently pay. With today's high tariffs, the system usually pays for itself in about 3–4 years and then delivers effectively free power for 20+ years.
Does the calculator account for net metering?
Yes. The default estimate assumes an on-grid, net-metered system, where surplus daytime generation is exported to the grid and credited against the units you draw at night — the most cost-effective setup for most Pakistani homes.
What is the payback period for solar in Pakistan?
For a net-metered residential system at current electricity tariffs, payback is usually 3–4 years. Larger bills and higher tariff slabs pay back faster because every unit you self-generate avoids a more expensive grid unit.
Do I need batteries with my solar system?
Not for savings. A grid-tied, net-metered system saves money without batteries. Batteries are only needed if you also want backup during load-shedding — they add cost and are optional. The calculator estimates a standard on-grid system by default; ask us for a hybrid (battery) quote if backup matters to you.
Does my city change the recommended system size?
Yes. Your city sets two things: local sun-hours (Karachi, Multan and interior Sindh get more usable sun than the far north) and your DISCO tariff (K-Electric, LESCO, IESCO and others bill differently). Both feed into the size and savings estimate, which is why the calculator asks for your city.
How much roof space do I need?
Plan for roughly 60–70 square feet of shade-free roof per kW. So a 10 kW system needs about 600–700 sq ft of clear space. If your roof is tight, higher-wattage panels can reduce the footprint — we confirm the exact layout during the free survey.
Is the calculator estimate the same as a final quote?
No — it's a fast, free estimate to help you plan. Your final quote comes after a free expert survey that verifies your roof, wiring, shading and exact load, and reflects live equipment prices. The two are usually close, and the survey is free with no obligation.
