The PHCN, or Power Holding Company of Nigeria, measures its electrical energy in kilowatt-hours (KWh). This is a unit of energy that is commonly used to measure the amount of electricity that is consumed or generated over a period of time. A kilowatt-hour is equivalent to the amount of energy consumed or generated by a one kilowatt power source in one hour. So, by measuring the electrical energy in kilowatt-hours, PHCN can keep track of how much electricity is being used by its customers and bill them accordingly.