How Much Does Air Conditioning Cost to Run?
Compare a fan, portable air conditioner, plug-in heater and our Bronze, Silver and Gold inverter systems using your own electricity tariff.
Current Calculator Default
Average electricity unit rate for Direct Debit customers under the Ofgem cap, 1 July to 30 September 2026.
You can replace this with the rate shown on your own electricity bill.
Air Conditioning Running Cost Calculator
Choose an appliance, enter your tariff and usage, then view an illustrative rated-input estimate.
Your Usage
Use the electricity unit rate shown on your bill for the most relevant estimate.
Bronze iPAC-12WS
12,000 BTU system with 3.5kW cooling output.
Published variable cooling-input range: 0.13–1.58kW. Actual use changes with load and operating conditions.
Hourly Cost Comparison
These bars update when you change the electricity tariff.
*Portable example assumes 1.5kW input. Products vary. Split-system figures use rated cooling input.
A Fan Is Cheaper. Air Conditioning Does More.
The useful comparison is not only price. It is also what the appliance does to the room.
Electric Fan
Moves air across your skin. It does not actively transfer heat outside or reduce the room's air temperature.
About 1.3p/hourPortable Air Conditioner
Actively cools but needs an exhaust hose. Noise, open-window sealing and product efficiency vary.
About 39.2p/hour*Wall-Mounted Split AC
Transfers heat outdoors through a sealed refrigerant circuit. It also provides heating, smart control and inverter modulation.
Bronze about 31.7p/hourOur Three Inverter Systems
Choose capacity based on the room's heat load, not by running cost alone.
iPAC-12WS
- ✓ 12,000 BTU cooling
- ✓ 3.5kW cooling output
- ✓ 1.213kW rated cooling input
- ✓ 0.13–1.58kW published range
- ✓ SEER 6.1 / SCOP 4.0
- ✓ Smaller suitable rooms
iPAC-18WS
- ✓ 18,000 BTU cooling
- ✓ 5.2kW cooling output
- ✓ 1.55kW rated cooling input
- ✓ 0.14–2.30kW published range
- ✓ SEER 7.4 / SCOP 4.0
- ✓ Larger suitable rooms
iPAC-24WS
- ✓ 24,000 BTU cooling
- ✓ 7.0kW cooling output
- ✓ 2.60kW rated cooling input
- ✓ 0.42–3.15kW published range
- ✓ SEER 6.1 / SCOP 4.0
- ✓ Large suitable spaces
Why Inverter Air Conditioning Does Not Stay at Full Power
Rated input is a useful comparison figure, but it is not a prediction of constant consumption.
Room Is Hot
The system increases output to remove heat and move towards the selected temperature.
Temperature Approaches Setpoint
The inverter can reduce compressor speed rather than repeatedly operating at one fixed output.
Steady Comfort
Consumption then depends on the heat entering the room, the setpoint and the system's minimum modulation.
Heating Cost: Heat Pump vs Plug-In Heater
This comparison shows the illustrative electricity cost per useful kWh of heat.
2kW Resistance Heater
26.11pIllustrative electricity cost per useful kWh of heat, assuming near one-for-one conversion.
AC Heat Pump at SCOP 4.0
6.53pIllustrative seasonal electricity cost per useful kWh of heat. Real performance varies with conditions.
Features That Help Control Energy Use
Comfort and control matter as much as the headline electrical input.
Wi-Fi App Control
Switch the system on or off remotely and avoid cooling an empty room unnecessarily.
Timer and Scheduling
Set operating periods around sleep, work and occupancy patterns.
Follow Me Sensing
Compatible controls can measure temperature closer to where you are sitting.
Inverter Modulation
Compressor output can reduce as the room approaches the selected temperature.
Silence and Sleep Modes
Lower fan settings support quieter overnight operation where suitable.
Heating and Cooling
One installed system provides summer cooling and reverse-cycle winter heating.
How to Reduce Air Conditioning Running Costs
Air Conditioning Running Cost Questions
How much does air conditioning cost per hour?
Multiply the unit's electrical input in kW by your electricity price in pence per kWh. At 26.11p per kWh, the rated-input estimates are about 31.7p for Bronze, 40.5p for Silver and 67.9p for Gold.
Is a fan cheaper than air conditioning?
Yes. A 50W fan costs about 1.3p per hour at 26.11p per kWh. A fan creates airflow but does not actively remove heat from the room.
Does a fan cool a room?
A fan can make people feel cooler through moving air and evaporation. It does not transfer the room's heat outdoors like an air conditioner.
Is wall-mounted AC cheaper than portable AC?
It depends on the two products, their efficiency, room conditions and usage. Wall-mounted split systems avoid an open exhaust hose arrangement and use inverter technology, but a fair cost comparison must use each product's actual electrical input.
Does AC use less electricity after reaching temperature?
An inverter system can reduce compressor output as the room approaches the setpoint. Actual consumption depends on the heat entering the room and the unit's operating range.
How much does AC cost overnight?
Enter the hours used into the calculator. Eight hours at rated input and 26.11p per kWh gives about £2.53 for Bronze, £3.24 for Silver and £5.43 for Gold. Actual inverter use may differ.
Is AC heating cheaper than a plug-in heater?
A resistance heater uses about one unit of electricity for one unit of heat. A heat-pump system with SCOP 4.0 can provide about four units of seasonal heat for one unit of electricity under rated conditions.
Which AC package is cheapest to run?
Bronze has the lowest rated electrical input. However, choosing a unit that is too small can reduce comfort and make it work harder. Capacity should be based on heat load.
Should I leave air conditioning running all day?
There is no single answer for every property. Use schedules, close doors and windows, and avoid cooling empty rooms. The best approach depends on occupancy and how quickly the room gains heat.
Sources: Ofgem unit rates · iPAC-12WS electrical input · iPAC-18WS electrical input · iPAC-24WS electrical input.
Choose the Right System, Not the Biggest System
Send room measurements and photos. We will assess the heat load and recommend Bronze, Silver or Gold.