Power in watts (W) to energy in kilowatt-hours (kWh) calculator and calculation formula.

**How to calculate :-** Enter the power in watts, consumption time period in hours and press the *Calculate* button:

The energy E in kilowatt-hours (kWh) is equal to the power P in watts (W),

times the time period t in hours (hr) divided by 1000:

*E*_{(kWh)} = *P*_{(W)} × *t*_{(hr)} / 1000