How to convert electric power in kilowatts (kW) to energy in joules (J).
You can calculate joules from kilowatts and seconds, but you can't convert kilowatts to joules since kilowatt and joule units represent different quantities.
Kilowatts to joules calculation formula
The energy E in joules (J) is equal to 1000 times the power P in kilowatts (kW), times the time period t in seconds (s):
E(J) = 1000 × P(kW) × t(s)
So
joules = 1000 × kilowatts × seconds
or
J = 1000 × kW×s
Example
What is the energy consumption of an electrical circuit that has power consumption of 3 kilowatts for time duration of 3 seconds?
E(J) = 1000 × 3kW × 3s = 9000J