How to convert electric power in kilowatts (kW) to energy in kilojoules (kJ).
You can calculate kilojoules from kilowatts and seconds, but you can't convert kilowatts to kilojoules since kilowatt and kilojoule units represent different quantities.
The energy E in kilojoules (kJ) is equal to the power P in kilowatts (kW), times the time period t in seconds (s):
E(kJ) = P(kW) × t(s)
So
kilojoules = kilowatts × seconds
or
kJ = kW×s
What is the energy consumption of an electrical circuit that has power consumption of 3 kilowatts for time duration of 3 seconds?
E(kJ) = 3kW × 3s = 9kJ