Yes — an inverter aircon is one of the easiest large appliances to run on solar. It starts gently, without the current spike of a fixed-speed compressor, and once the room is cool it runs at a fraction of its full power.
How much power does it need?
A 9 000 BTU inverter draws about 0.8 kW at full output and often 0.3–0.6 kW once the room is cool; a 12 000 BTU unit about 1.1 kW at full output. Larger units scale up from there. Check the power input on the specification sheet of the model you choose, and see the chart in our running cost guide.
Inverter size
Your solar or backup inverter must supply the aircon’s full power input plus everything else running at the same time. A 5 kW inverter will usually run one or two bedroom units alongside normal household loads; larger units and several aircons need a bigger system. Ask your solar installer to check.
Battery size
Battery energy needed ≈ the aircon’s average power × hours. A bedroom inverter averaging 0.5 kW for 8 hours uses about 4 kWh — a big share of a typical 5 kWh home battery. Cooling during the day on solar is easy; running large units all night on batteries needs a large battery bank.
Tips
- Cool or heat the house while the sun is out, then let it coast.
- Set 24–25 °C and close the room.
- Choose a fixed-speed unit only if you will never run it on solar or backup power.
- Use Wi-Fi control to switch units off remotely when the battery is low.
Can I run an aircon on a 5kW inverter?
Usually one or two bedroom-size inverter aircons, as long as the total of everything running at once stays within the inverter’s rating. Large or fixed-speed units may be too much.
Can an aircon run during load shedding?
Only on a backup system — solar with batteries, a battery inverter or a generator. Because an inverter aircon uses little power once the room is cool, it is well suited to running from a battery for a few hours.
Will a generator run my aircon?
Yes, if the generator is large enough for the aircon and anything else connected. An inverter aircon is easier on a generator because it has no large start-up surge.