Recall that the rate at which energy is converted from one form to another is power.
power = energy converted / time
power = (voltage x charge) / time power = voltage x (charge / time) power = voltage x current
The unit of power is the watt (or kilowatt = 1000 watts).
So in terms of units,
electric power (watts) = current (amperes) x voltage (volts)
Thus, 1 watt = 1 joule / 1 second = 1 ampere x 1 volt.
