Before buying solar, you need to know your load: how many watts your appliances draw and how many units they use each day. This solar load calculator adds up your fans, lights, ACs, fridge and pump, then tells you the solar system size, number of panels and inverter you need.
Solar Load Calculator
Apne appliances add karein: wattage, quantity aur roz ke ghante.
Uses 5 peak sun hours and 80% system efficiency. Refrigerators and ACs cycle on and off, so their real use is usually lower than rated wattage × hours.
How to use the solar load calculator
- Pick each appliance from the list. Typical wattages are already filled in.
- Enter how many of each you have and how many hours a day they run.
- Tap + Add appliance for anything missing, and × to remove a row.
- Read the results: total load in watts, daily and monthly units, recommended solar size and inverter.
How the calculation works
- Daily energy = wattage × quantity × hours, added up for every appliance and divided by 1,000 to get kWh (units).
- Solar size = daily units ÷ (5 peak sun hours × 80% efficiency), rounded up to the nearest 0.5 kW.
- Inverter = the bigger of your solar size or 125% of your total connected load, rounded up to a standard size.
8 LED lights for 8 hours, 4 fans for 12 hours, one 1.5-ton inverter AC for 8 hours, a fridge for 12 hours and a TV for 5 hours use about 19.5 units a day, or roughly 585 units a month. That calls for a system of about 5 kW, or 9 panels of 585W.
Typical appliance wattage in Pakistan
| Appliance | Typical watts | Notes |
|---|---|---|
| LED bulb / tube | 9 – 20 W | Lowest load in most homes |
| Ceiling fan (AC motor) | 70 – 90 W | DC inverter fans use 30–40 W |
| 1.5 ton inverter AC | 800 – 1,600 W | Draws less once the room cools |
| 1.5 ton non-inverter AC | 1,800 – 2,200 W | Hard to run on small systems |
| Refrigerator | 150 – 250 W | Compressor cycles on and off |
| Water pump (1 HP) | 750 W | High starting surge |
| Iron | 1,000 – 1,200 W | Short use, but high load |
Tips to reduce your solar load
- Switch to inverter ACs and DC fans; they cut load sharply.
- Run the pump, washing machine and iron during sunny hours.
- Replace old fridges, which can use twice the power of new inverter models.
Next: check today’s solar panel prices, find the right inverter with our inverter size calculator, or see all solar calculators.
Frequently asked questions
How do I calculate my home’s load for solar?
Multiply each appliance’s wattage by its quantity and daily hours, add them up and divide by 1,000 to get daily units. Divide that by about 4 (5 sun hours × 80% efficiency) to get the solar size in kW.
How much solar do I need to run one AC?
A 1.5-ton inverter AC running 8 hours a day needs roughly 2.5–3.5 kW of solar, depending on outside temperature and how cool you keep the room.
What is the difference between load and units?
Load (watts) is how much power appliances draw at the same moment, which decides your inverter size. Units (kWh) are energy used over time, which decides how many panels you need.
Prices and rules change often. This page was last reviewed on 12 November 2026. Spotted an outdated rate? Tell us and we'll update it.