How to convert watt-hours to watts

How to convert energy in watt-hour (Wh) to electric power in watts (W).

You can calculate watt from watt-hour and hours, but you can't convert watt-hour to watt units, since watt-hour and watt units represent different quantities.

Watt-hour to watts calculation formula

The power P in watts (W) is equal to the energy E in watt-hour (Wh), divided by the time period t in hours (h):

P(W) = E(Wh) / t(h)


watts = watt-hours / hours


W = Wh / h


What is the power consumption in watts when the energy consumption is 15 watt-hour for time duration of 3 hours?

P = 15 Wh / 3 h = 5 W

Kilowatt-hour definition

Kilowatt-hour is an energy unit (symbol kWh or kW⋅h).

One kilowatt-hour is defined as the energy consumed by power consumption of 1kW during 1 hour:

1 kWh = 1kW ⋅ 1h

One kilowatt-hour is equal to 3.6⋅106 joules:

1 kWh = 3.6⋅10J

The energy E in kilowatt-hour (kWh) is equal to the power P in kilowatts (kW), times the time t in hours (h).

E(kWh) = P(kW) ⋅ t(h)

Watt definition

Watt is the unit of power (symbol: W).

The watt unit is named after James Watt, the inventor of the steam engine.

One watt is defined as the energy consumption rate of one joule per second.

1W = 1J / 1s

One watt is also defined as the current flow of one ampere with voltage of one volt.

1W = 1V × 1A

How to convert watts to Wh »

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