1. Find the running current of the air conditioning unit and multiply it by the voltage. This will give you the Watts.
2. Multiply the Watts by the average running hours of use per day. This will give you the Kilowatt Hours (kWh).
3. Then multiply this by the electricity unit rate you are paying for.
Mitsubishi Electric MSZ-AP25VGK running current on cooling mode = 2.9A
2.9A x 240v = 696W
696W x 8hours per day = 5568
5568/1000= 5.57kWh per day
5.57kWh x £0.21 (electric unit rate) = Total Cost £1.17 per day