Estimate assumes 80% system efficiency and planning-average sun hours. Inverter, batteries, structure and installation are extra.
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The calculator above works out the solar panel for a 1.5 ton AC, or a 1 ton or 2 ton unit, from three things: the AC size, whether it is a DC inverter or an old non-inverter model, and which panel you plan to buy. Below we explain the method, show worked examples with live panel prices, and list what else on your load (fridge, motor, fans, air cooler) needs to be added before you size an AC solar panel setup.
How the calculation works
An AC does not use its full tonnage in watts all the time. The calculator turns tonnage into running watts, adds a safety margin, and divides by your panel’s wattage.
- Running load. We take 1.0 kW per ton for a DC inverter AC and 1.5 kW per ton for a non-inverter AC. A 1.5 ton inverter AC is therefore treated as 1.5 kW, and a 1.5 ton non-inverter as about 2.25 kW.
- Margin. We add 25% to cover morning and evening sun, heat on the panels, dust and cable losses. Panels in Lahore or Multan in June rarely give their full label wattage.
- Panels. System watts divided by the panel wattage, rounded up. You cannot buy half a plate.
- Daily units. AC kW multiplied by the hours you run it, multiplied by 0.7, because the compressor slows down or cycles once the room is cool.
Where those numbers come from
The 1.0 kW per ton figure is close to what makers publish. Gree’s 1.5 ton DC inverter model GS-18PITH11S, sold widely in Pakistan, lists a rated cooling input of 1,450 W, with a range from 350 W when it is just holding temperature to 1,900 W at full boost. A fixed-speed non-inverter AC cannot slow down. With about 5.3 kW of cooling output for 18,000 BTU and the lower efficiency of older units, it pulls roughly 1.7 to 2 kW whenever the compressor is on, so 1.5 kW per ton keeps you safe.
| AC size | Cooling (BTU) | Inverter AC load used | Non-inverter load used |
|---|---|---|---|
| 1 ton | 12,000 | 1.0 kW | 1.5 kW |
| 1.5 ton | 18,000 | 1.5 kW | 2.25 kW |
| 2 ton | 24,000 | 2.0 kW | 3.0 kW |
One example in plain words: a 1.5 ton inverter AC is 1.5 kW. Add 25% and you need about 1.9 kW of panels. With 585 watt plates, 1,875 divided by 585 is 3.2, so you buy 4 panels.
Inverter vs non-inverter AC on solar
If you are still choosing an AC, this comparison matters more than the panel brand:
| DC inverter AC | Non-inverter AC | |
|---|---|---|
| How the compressor works | Speeds up and slows down | Full power on, then off |
| Start-up surge | Low, soft start | High, can trip a small inverter |
| Panels for 1.5 ton (585 W) | 4 | 5 |
| Daytime units on solar | Lower, because it slows down once cool | Higher |
| Best for | Solar homes, long daily running | Short use, existing units |
A non-inverter AC can run on solar, but you pay for an extra panel and need a larger inverter to survive the start-up kick. Many families who go solar replace the old unit in the main bedroom first.
Worked examples: 1 ton, 1.5 ton and 2 ton AC
These are the answers the calculator gives with 585 W panels, which are the most common size on Pakistani rooftops. Costs are panels only and update with our daily price sheet.
| AC | Type | Panels needed (585 W) | Panels cost today | Daily solar units (8 hours) |
|---|---|---|---|---|
| 1 ton | DC inverter | 3 | Rs 70,200 | about 5.6 |
| 1 ton | Non-inverter | 4 | Rs 93,600 | about 8.4 |
| 1.5 ton | DC inverter | 4 | Rs 93,600 | about 8.4 |
| 1.5 ton | Non-inverter | 5 | Rs 117,000 | about 12.6 |
| 2 ton | DC inverter | 5 | Rs 117,000 | about 11.2 |
| 2 ton | Non-inverter | 7 | Rs 163,800 | about 16.8 |
How many solar panels are required for a 1.5 ton AC
So, how many solar panels are required for a 1.5 ton inverter AC? Four 585 W panels run it through the middle of a sunny day. A 1.5 ton non-inverter AC needs five. If you choose bigger 620 W plates, the count for the inverter AC stays at four, but you get more margin on hazy days.
How many solar panels are required for a 1 ton AC
A 1 ton DC inverter AC is happy on three 585 W panels. A 1 ton non-inverter needs four, the same as a 1.5 ton inverter model. That is the clearest argument for replacing an old non-inverter AC before going solar: the newer AC cuts the panel count.
What a solar panel AC setup costs in Pakistan
The panel cost above is only part of the solar panel for AC price in Pakistan. You also need:
- An inverter. For one 1.5 ton AC, most installers fit a hybrid or on-grid inverter of 3 kW or more so the AC, fridge and fans can run together. See our solar inverter price guide.
- A mounting structure, DC cable, breakers and earthing.
- Batteries only if you want the AC to run after sunset, which is expensive. Check the solar battery price page before deciding.
Solar panels needed for common appliances
An AC is rarely the only thing running. Add the rest of your daytime load to the AC result before buying. The figures below are typical running watts for appliances in Pakistani homes; check the label on yours.
| Appliance | Typical running watts | 585 W panels for this alone | Notes |
|---|---|---|---|
| 1 ton DC inverter AC | about 1,000 W | 3 | Soft start, easy on the inverter |
| 1.5 ton DC inverter AC | about 1,450 W | 4 | The most common solar AC choice |
| 1.5 ton non-inverter AC | about 1,700 to 2,000 W | 5 | High start-up surge |
| Refrigerator | 150 to 250 W | 1 shared | Runs all day; needs grid or battery at night |
| Water motor (1 hp) | about 750 W | 2 | Start-up surge is two to three times running watts |
| Ceiling fan (AC type) | 75 to 100 W | 1 for 5 to 6 fans | Inverter or DC fans use roughly half |
| Air cooler | 150 to 250 W | 1 | The cheapest way to cool a room on solar |
| LED lights | 10 to 20 W each | small share | Negligible |
On-grid, hybrid or a “solar AC”?
There are three ways to run an AC on solar panels, and the panel count above applies to all of them:
- On-grid inverter with your normal AC. The cheapest route. Panels power the AC in the day and the grid fills any shortfall. It stops during load-shedding unless the inverter has backup.
- Hybrid inverter. Works with the grid, panels and an optional battery. The AC keeps running during daytime load-shedding as long as the sun is strong.
- DC or hybrid “solar AC” units. Some AC makers sell models that take panel power directly into the outdoor unit. They avoid a separate inverter for the AC but tie you to one brand’s design, and spare parts are harder to find.
For most homes, a normal DC inverter AC with a hybrid inverter is the flexible choice: you can add panels or a battery later.
Air cooler with solar panel
If an AC is out of budget, an air cooler with a solar panel is a practical start. One 585 W panel and a small inverter will run a room cooler and a couple of fans through the day. In dry cities like Multan and Faisalabad a cooler works well; in humid Karachi, a 1 ton inverter AC usually makes more sense.
Putting it together
A typical family running a 1.5 ton inverter AC, a fridge, four fans and lights in the daytime needs about 2.1 kW of running load. Add 25% and the panel need is about 2.6 kW, or five 585 W panels. For your whole house, including night units and the monthly bill, switch to the solar panel calculator, which sizes from your bill units.
Tips for an accurate result
The calculator is a sound starting point, but your roof and your habits change the answer. Before you order:
- Check the AC label. Look for “rated power input” in watts on the outdoor unit sticker. If it is higher than our figure, use yours.
- Be honest about hours. Running the AC from 11 am to 7 pm means two hours with weak or no sun. Those hours come from the grid or a battery, not the panels.
- Avoid shade. A water tank or a neighbour’s wall shading one plate in the afternoon pulls down the whole string. Place panels where they get sun from about 9 am to 4 pm.
- Face south. In Pakistan, panels facing south at the right tilt give the most output. Our tilt angle calculator gives the angle for your city.
- Leave space for one more panel. Summer heat cuts panel output, and dust adds to the loss. A spare spot on the structure is cheap insurance.
- Use A-grade panels. Our best solar panels in Pakistan guide covers which brands hold their output in heat, and today’s rates are on the solar panel price list.
Summer vs winter
| Season | What changes | What to do |
|---|---|---|
| May to August | Highest AC use, but heat cuts panel output by several percent | Size for this season; keep the 25% margin |
| Monsoon | Cloudy spells drop output sharply for hours | Keep grid backup for the AC |
| October to March | AC barely runs; panels produce surplus | Use the extra for the water motor, iron and washing |
| Mistake | What happens | Fix |
|---|---|---|
| Sizing for tonnage, not running watts | You buy too many panels | Use the label’s rated input |
| Ignoring the 25% margin | AC trips on cloudy afternoons | Add one panel |
| Small inverter | Inverter overloads when AC and motor start together | Fit 3 kW or more for a 1.5 ton AC plus house load |
| Counting on panels after 5 pm | AC switches to grid or stops | Plan grid backup or battery |
Frequently asked questions
How many solar panels are required for a 1.5 ton inverter AC?
Four 585 watt panels, about 1.9 kW in total, run a 1.5 ton DC inverter AC through the sunny part of the day. That figure includes a 25% margin for heat, dust and weaker morning and evening sun.
How many solar panels are required for a 1.5 ton non-inverter AC?
Plan on five 585 watt panels, because a fixed-speed AC draws close to 2 kW whenever the compressor runs and has a strong start-up surge. You will also need a larger inverter than for an inverter AC.
How many solar panels are required for a 1 ton AC?
A 1 ton DC inverter AC needs three 585 watt panels, and a 1 ton non-inverter AC needs four. Use the calculator above to check with the panel size you plan to buy.
Can a 1.5 ton AC run on solar panels at night?
Not on panels alone. After sunset the AC runs from the grid or from a battery bank, and a battery big enough for an AC all night is expensive.
What size inverter do I need for a 1.5 ton AC on solar?
Most installers fit a 3 kW or larger hybrid or on-grid inverter for one 1.5 ton AC, so the fridge, fans and a water motor can run at the same time. A non-inverter AC needs extra headroom for its start-up surge.
Is an air cooler with a solar panel a good option?
Yes, for dry cities and tight budgets. A single 585 watt panel with a small inverter can run a room cooler and a couple of fans in the daytime, but coolers work poorly in humid weather like Karachi's.
What is the solar panel for AC price in Pakistan?
The panel cost changes with daily market rates, so the calculator above uses today's price sheet. Add the inverter, structure, wiring and installation to get the full cost.
Do I need a special solar AC?
No. A normal DC inverter AC works well with a hybrid or on-grid solar inverter. Dedicated solar ACs exist but tie you to one maker's design.