How to convert watts to kilojoules

How to convert electric power in watts (W) to energy in kilojoules (kJ).

You can calculate kilojoules from watts and seconds, but you can't convert watts to kilojoules since watt and kilojoule units represent different quantities.

Watts to kJ calculation formula

The energy E in kilojoules (kJ) is equal to the power P in watts (W), times the time period t in seconds (s):

E(kJ) = P(W) × t(s) / 1000


kilojoules = watts × seconds / 1000


kJ = W × s / 1000


What is the energy consumption of an electrical circuit that has power consumption of 300 watts for time duration of 3 seconds?

E(kJ) = 300W × 3s / 1000 = 0.9kJ


How to convert kJ to watts ►


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