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

So

kilojoules = watts × seconds / 1000

or

kJ = W × s / 1000

Example

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 ►

 


See also

Write how to improve this page

ELECTRICAL CALCULATIONS
RAPID TABLES