How much does an air conditioner cost to run each month?
It depends on the unit's electrical power, how many hours you use it and what you pay per kWh. Work it out with your own figures.
By the ClimaEasy team. Updated
Work out your running costs
Choose a type of unit or enter the electrical power shown on its spec sheet, and set the price per kWh to the one on your bill.
How it's calculated
Monthly cost = electrical power (kW) × hours per day × days × price per kWh
For example, a split that draws 0.6 kW, running 6 hours a day for 30 days, uses 0.6 × 6 × 30 = 108 kWh. At €0.15/kWh, that's about €16 a month.
The result is an upper estimate. Inverter units reduce their consumption once the room reaches the set temperature, so in practice they usually use less than at full load.
Don't confuse cooling power with electrical power
A "3.5 kW" split doesn't draw 3.5 kW. That figure is the cooling capacity, the cooling it produces. What you pay for is the electrical power it draws, which in an efficient unit is several times lower. You'll find it on the spec sheet or the energy label, next to the seasonal efficiency (SEER).
That's why, for the same cooling capacity, a split usually costs much less to run than a portable: it needs less electricity to produce the same cooling.
How to spend less
- Don't set the thermostat too low. Every degree lower makes the compressor work harder.
- Add a fan. Feeling cooler lets you set the thermostat a couple of degrees higher.
- Keep the sun out. Blinds and awnings reduce the heat the unit has to remove. More ideas in cooling without appliances.
- Clean the filters. A dirty filter reduces airflow and efficiency.
- Check your tariff. If you use it a lot in the afternoon and evening, compare the price of each time band.
Frequently asked questions
How much does a portable air conditioner cost to run per month?
A 9,000 BTU portable drawing about 1 kW, used 6 hours a day for 30 days, uses about 180 kWh. At an example price of €0.15/kWh, that's about €27 a month. Adjust the calculator with your unit and your tariff.
Does a portable or a split cost more to run?
For the same cooling capacity, the portable usually costs more, because it's less efficient, especially single-hose models.
Where can I find my unit's electrical power?
On the spec sheet or the rating plate on the unit itself. It appears as power input or consumption, in W or kW.