How Much Does It Cost to Keep Your Air Conditioner Running All Day? Experts Do the Math

There's no single figure that captures how much it costs to run an air conditioner — it all depends on the unit's power, the size and features of the room, the outdoor temperature, and how many hours a day the device is switched on. That's according to specialists from Daikin, PREenergo, and Panasonic Heating & Cooling Solutions.

According to Vladimír Havlíček, a technical support representative at Daikin, you can get a rough idea of cooling costs from the air conditioner's energy label — the figures on it are calculated for a temperate climate and vary depending on the model, power output, and type of split system.

How much it adds up to over a summer

Take, for example, a panel-building flat with a 2+1 layout, where two rooms are cooled by a multi-split system with a combined output of 4 kW. Over an entire summer, electricity consumption could come to around 164 kWh. At a rate of 6 crowns per kilowatt-hour, that works out to roughly 10 crowns a day. But that's an average figure for typical summer weather — on days when the temperature climbs to 40°C, costs can double or even triple, Havlíček warns.

Radek Šediv, a sales specialist for energy services at PREenergo, cites higher numbers. In his estimate, on tropical days a small system with one or two indoor units can cost 30–40 crowns a day to run. He stresses, though, that this is only a ballpark figure, since it's affected by many factors — including geography, as temperatures in southern Moravia and, say, in the Jizera Mountains can differ substantially.

Every degree counts

How you use your air conditioner also affects the final "price of staying cool." The most important factor is the temperature you set indoors. According to Radek Vanduch, a technical specialist at Panasonic Heating & Cooling Solutions, the optimal setting for economical cooling in summer is 24–26°C. Setting it to, say, 22°C will noticeably increase energy consumption — raising the target temperature by just one degree can cut cooling costs by roughly 6–10%.

It's also wise not to turn your flat into a fridge. Specialists recommend keeping the difference between the outdoor and indoor temperature within 5–6°C — that way, the air conditioner won't have to work at full capacity, and moving between the cool indoors and the heat outside will be gentler and safer for your body.

Around Prague, based on reporting by novinky.cz