The most common unit of measurement on the electricity meter is the kilowatt hour [ kWh ], which is equal to the amount of energy used by a load of one kilowatt over a period of one hour, or 3,600,000 joules.nother type of smart meter uses nonintrusive load monitoring to automatically determine the number and type of appliances in a residence, how much energy each uses and when. This meter is used by electric utilities to do surveys of energy use.