Air conditioning is what decides solar system size in Pakistan. Everything else in a typical home, lights, fans, a fridge, a TV, adds up to a few hundred watts. One inverter AC can draw more than all of it combined. This page works through the arithmetic honestly.
What an air conditioner actually draws
- 1 ton inverter AC: roughly 700 to 1,000 watts while running
- 1.5 ton inverter AC: roughly 1,000 to 1,400 watts
- 2 ton inverter AC: roughly 1,500 to 1,900 watts
- Conventional (non-inverter) AC: considerably more, and with a heavy startup surge
An inverter AC modulates its compressor instead of switching on and off at full power, so it settles to a lower steady draw once the room is cool. On solar that difference is decisive, and it is the single cheapest upgrade before you size a system.
Panels per air conditioner
To run one 1.5-ton inverter AC through daylight hours you want roughly 2 to 3 kW of panels dedicated to it, which is four to five modern 600 W panels. That allows for the fact that panels rarely produce their rated output: cloud, heat, dust and the angle of the sun all take a share.
Then add the rest of the house, usually 1 to 2 kW of general load. So:
| Air conditioners running by day | Sensible system size | On-grid price |
|---|---|---|
| One 1.5 ton | 5 kW | Rs 350,000 |
| Two | 8 kW | Rs 560,000 |
| Three to four | 10 kW | Rs 700,000 |
| Five to six | 15 kW | Rs 1,050,000 |
The night problem
Panels produce nothing after sunset, and in Pakistan air conditioning is often wanted most at night. On an on-grid system that consumption comes from the grid at the full tariff. On a hybrid it comes from the battery.
A 1.5-ton inverter AC running five evening hours needs roughly 6 kWh of usable storage, which means about a 7 to 8 kWh lithium bank once you allow for usable depth. Two ACs through the evening pushes you toward 12 to 15 kWh. See our battery sizing guide.
Do not size for the worst week of July
It is tempting to size for the hottest afternoon of the year. Under net billing that is usually a mistake: the extra capacity exports at about Rs 11 for the other eleven months to cover a handful of extreme days. Size for your typical daytime load and accept drawing from the grid at the true peak.
Practical ways to get more from the same system
- Set the thermostat to 26 °C. Every degree lower costs meaningful power.
- Clean the filters monthly. A clogged filter makes the compressor work harder for the same cooling.
- Service the outdoor unit. A dusty condenser in a Lahore summer is a permanent efficiency tax.
- Shift other heavy loads into daylight, so the AC is not competing with the washing machine and the water pump for solar output.
Frequently asked questions
How many solar panels do I need to run one AC?
A 1.5-ton inverter air conditioner draws roughly 1,000 to 1,400 watts while running. To run it through the day you need about 2 to 3 kW of panels dedicated to it, which is four to five 600 W panels, plus capacity for the rest of the house.
Can solar run an AC at night?
Only with a battery. Panels produce nothing after sunset, so night-time air conditioning comes from the grid on an on-grid system, or from storage on a hybrid. A 1.5-ton inverter AC for five evening hours needs roughly 6 kWh of usable battery.
How many ACs can a 10 kW system run?
Comfortably three to four inverter ACs during daylight, alongside normal household load. That is the most common reason Lahore homes land on 10 kW.
Is an inverter AC necessary for solar?
Not necessary, but strongly advisable. A conventional AC draws a large surge at startup and runs at full power; an inverter AC modulates and uses substantially less. On solar, that difference decides how many units you can run.
Should I size solar for peak summer AC use?
Size for your typical daytime load, not the worst July afternoon. Under net billing an oversized system exports surplus at about Rs 11 for most of the year to cover a few extreme weeks, which rarely pays.
See system prices in Lahore or work out what solar would actually save you.
Want this worked out for your own ACs?
Tell us how many air conditioners you run, what size, and roughly when, on WhatsApp 0321 878 3630. SNM Solutions will size the system and battery around your real usage, free.