kwh is the unit of power?
One thousand Watts is one kilowatt, abbreviated kW. That's a measure of power. If you use one kilowatt of power for an hour, you have used 1 kilowatt-hour, abbreviated kWh, of energy. One kilowatt-hour is equivalent to the energy of 1,000 joules used for 3,600 seconds or 3.6 million Joules.