Solar System for 5 Marla House
A typical 5 marla house with fans, LED lights, an inverter fridge, a TV, one 1.5 ton inverter AC, a water pump and an iron needs a solar system of about 5.27 kW (9 panels of 585 W) with a 5.11 kW inverter. The system size is the larger of daily units ÷ sun yield and running watts ÷ performance ratio.
How this result was calculated
Energy: each appliance's watts × quantity × hours a day (an inverter AC counts at its average draw, below its rated watts), added up = 15.6 units a day; ÷ 4 units per kW of panels a day for your city = 3.91 kW. Power: 4,085 W running load ÷ 0.78 performance ratio = 5.24 kW so the panels alone can carry the house at midday. The larger of the two, 5.24 kW, needs 9 panels of 585 W = 5.27 kW installed, which makes about 632 units a month. Inverter = 4,085 W × 1.25 = 5.11 kW, with a surge rating of at least 5,885 W for the water pump.
Key facts
- A typical 5 marla house with one 1.5 ton inverter AC has a running load of about 4,085 W and uses about 15.6 units a day, so it needs a solar system of about 5.27 kW with a 5.11 kW inverter.
- Solar system size in kW = the larger of (units a day ÷ sun yield per kW) and (running watts ÷ performance ratio); the second rule makes sure the panels can run the AC at midday without a battery.
- One kW of panels makes about 4 units a day in Lahore over the year, so a 5.27 kW system makes about 632 units a month.
- Panels are counted up to the next whole panel: 5.24 kW ÷ 585 W = 9 panels, about 23 square metres of roof.
Formula
kW = max(E_day ÷ yield, P_run ÷ 1000 ÷ PR); panels = ceil(kW × 1000 ÷ W_panel)
- E_day = Σ (watts × qty × hours) ÷ 1000, units used a day
- yield = units one kW of panels makes a day in your city
- P_run = total running watts, PR = performance ratio
- W_panel = watts of one panel
- Inverter kW = P_run × margin ÷ 1000; surge ≥ largest starting load
- Battery Ah = P_run × night hours ÷ (V × DoD × η)
What is the electrical load of a 5 marla house?
A 5 marla house usually has two or three bedrooms, a lounge, a kitchen and one or two bathrooms. The default list above is what runs in such a house in summer: four ceiling fans, ten LED bulbs, an inverter fridge, a TV, one 1.5 ton inverter AC, a water pump and an iron. Together they come to 4,085 W running and 15.6 units a day, which is about 632 units a month from the solar system.
The running load, not the daily units, is what sets the size here. The AC, the pump and the fans can all be on at noon, so the panels must carry 4,085 W by themselves. If your house has fewer or more appliances, change the list and the result updates.
How many kW solar for a 5 marla house?
For the typical house above the answer is 5.27 kW of panels with a 5.11 kW inverter. The energy rule alone would ask for 3.91 kW, but the power rule (4,085 W ÷ 0.78) asks for 5.24 kW so the house runs on sun at midday, and the larger number wins.
The panel count is rounded up, so the installed size is a little above the calculated 5.24 kW. Installers quote by inverter size, which is why this house is sold as a five kW system.
When is a 5 kW solar system right for a 5 marla house?
A five kW inverter with 9 panels suits a 5 marla house with one inverter AC, fans, lights, a fridge and a pump, which is exactly the default above. It runs the whole house in the day and feeds spare units to the grid.
With two inverter ACs running at the same time the running load goes above the inverter rating, and the calculator moves you to the next size. See the second worked example below for that house.
Solar for a 5 marla house with one AC
One 1.5 ton inverter AC is the single biggest load in the list. On average it draws about 1 kW while running, which is most of the house's daily units in summer. The default result is the one-AC case: 5.27 kW of panels and a 5.11 kW inverter.
If the AC is non-inverter, the starting surge is much larger and the inverter must handle it. Pick the non-inverter AC in the list and the surge rating in the result changes.
What does a 5 marla solar system cost?
We do not print a price here because panel and inverter prices in Pakistan move with the dollar rate and change from month to month. Ask for quotes in Rs per watt of panels, so a 5.27 kW system is compared like for like; a quote checker that compares your quote against the current market range is coming to this site.
A complete quote must include the panels, the inverter, the mounting structure, DC and AC cables, breakers and surge protection, earthing, installation labour and, for a grid-tied system, the net-metering or net-billing application and the bidirectional meter. A quote that leaves any of these out looks cheaper than it is.
Do you need a battery for a 5 marla solar system?
A grid-tied system with no battery is the cheapest and runs the house in the day; at night you buy from the grid. If your area has load shedding after sunset, enter the hours of backup you want and the calculator adds a lithium battery sized for the full running load for those hours.
The battery figure is for every appliance in your list running after dark. Most houses run only fans, lights and the fridge at night, so make a second list without the AC and pump to size a smaller battery.
Worked examples
Typical 5 marla house with one inverter AC
Four fans, ten bulbs, an inverter fridge, a TV, one 1.5 ton inverter AC, a water pump and an iron: 4,085 W running and 15.6 units a day. Solar system 5.27 kW (9 panels), inverter 5.11 kW, about 632 units a month.
5 marla house with two inverter ACs
The same house with a second 1.5 ton inverter AC: 5,535 W running and 23.6 units a day. Solar system 7.61 kW (13 panels), inverter 6.92 kW, about 913 units a month. This is a step above a five kW system.
Typical house with 5 hours of battery backup
The default house with 5 hours of backup after sunset on a 48 V lithium bank: the panels and inverter stay at 5.27 kW and 5.11 kW, and the battery must hold 20.4 units, which is about 525 Ah at 48 V using 90% of it. Running only fans, lights and the fridge at night needs a far smaller battery.
5 marla house without an AC
Fans, bulbs, fridge, TV, pump and iron only: 2,635 W running and 7.6 units a day. Solar system 3.51 kW (6 panels), inverter 3.29 kW. The water pump and iron set the running load even though they run for a short time.
Solar system size for common 5 marla house setups in Lahore sun, from a small house with no AC (first row) to two inverter ACs with an electric geyser (last row)
| House | Solar system | Panels | Inverter | Units a month |
|---|---|---|---|---|
| 4 kinds of appliance, 576 W running, 5.2 units a day | 1.76 kW | 3 × 585 W | 0.72 kW | 211 |
| 6 kinds of appliance, 2,635 W running, 7.6 units a day | 3.51 kW | 6 × 585 W | 3.29 kW | 421 |
| 7 kinds of appliance, 4,085 W running, 15.6 units a day | 5.27 kW | 9 × 585 W | 5.11 kW | 632 |
| 7 kinds of appliance, 4,435 W running, 19.2 units a day | 5.85 kW | 10 × 585 W | 5.54 kW | 702 |
| 7 kinds of appliance, 5,535 W running, 23.6 units a day | 7.61 kW | 13 × 585 W | 6.92 kW | 913 |
| 8 kinds of appliance, 8,535 W running, 29.6 units a day | 11.12 kW | 19 × 585 W | 10.67 kW | 1,334 |
Common mistakes
- Sizing from the monthly bill alone. The bill gives the energy rule, but a house with an AC is usually limited by the power rule, so the system comes out too small to run the AC at noon without the grid.
- Forgetting the pump and iron. They run for minutes, but they are on the running load when they do, and the pump's starting surge sets the inverter's surge rating.
- Buying an inverter equal to the panel kW. The inverter is sized from the running load with a margin; the panels are sized from energy and power, and the two numbers are different.
- Expecting the rated panel watts every day. The performance ratio of 78% covers heat, dust, cable loss and cloudy days; the units a month shown is the realistic yearly average, not a sunny-day peak.
- Sizing a battery for the whole house. The battery line assumes every listed appliance runs after dark; list only the night loads for a battery you can afford.
Safety: A rooftop solar system connects to the grid and to your house wiring at mains voltage; have a licensed electrician and a DISCO-approved installer do the wiring, earthing and net-metering connection.
Frequently asked questions
How many solar panels does a 5 marla house need?
The typical 5 marla house above needs 9 panels of 585 W, which is 5.27 kW and about 23 square metres of roof. Smaller panels mean more panels for the same kW.
Is a 5 kW solar system enough for a 5 marla house?
Yes for one 1.5 ton inverter AC with fans, lights, a fridge and a pump, which needs 5.27 kW of panels and a 5.11 kW inverter. For two ACs at the same time, or an electric geyser, the calculator moves to the next size.
How many units will a 5 marla solar system make a month?
About 632 units a month for the 5.27 kW system in Lahore, as a yearly average. Summer months make more and winter months less; choose your city above for its own sun yield.
Can I run a 1.5 ton AC on a 5 marla solar system?
Yes. The power rule sizes the panels so the 4,085 W running load, including the AC, runs on sun alone at midday. In the evening the AC runs from the grid or from a battery.
What is the price of a solar system for a 5 marla house?
Prices change with the dollar rate, so we do not print one. Compare quotes in Rs per watt for a complete system of 5.27 kW, including structure, cables, protection, installation and the net-metering application.
Grid-tied, hybrid or off-grid for a 5 marla house?
Grid-tied is cheapest and sells spare units to the grid. Hybrid adds a battery for load shedding, sized with the backup hours field above. Off-grid needs a battery for every night and cloudy day and is rarely worth it where the grid is available.
Why does the result change when I add an appliance that runs for a few minutes?
The panels must carry the full running load at midday, so any appliance that can be on at the same time counts. If the iron or pump never runs with the AC, remove it from the list for the panel size and keep it in mind for the inverter surge rating.
Sources
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