The device that is used to measure the consumption amount of electrical energy that is being used up by any residential accommodation, a business facility or simply a device that is powered electrically is known as an electric energy meter.
These electric meters are installed at the customer sites by the electric utilities. The provided electric energy that is then being consumed by the customers is measured. These measurements are in turn used for the billing calculations by the utilities.
The measurements are particularly standardized in billing units. The most commonly used unit is the kilowatt hour [kWh]. The measurements are mostly recorded once each predefined period for billing. Whenever the requirement is that of energy savings in a particular period of time, there are meters specially designed for the measurement of demand, and the highest possible demand of power in a specific duration.
The concept of “Time of day” metering is the one in which it is possible to modify electric rates during a day. Due to this it is now possible to measure and log consumption during the high-cost intervals and the lower-cost intervals of the day. Moreover, there are meters which consist of relays. These relays play a vital role in demand response load shedding which is a requirement of peak load intervals.
There are various units of measurement for electric energy but the most widely used is the kilowatt hour [kWh]. It is equivalent to the energy consumed by a one kilowatt load in an interval of one hour or 3,600,000 joules. There are a few electric companies that prefer to make use of the SI megajoule unit instead of the primitive unit.
The demand measurement is usually made in watts, but the average is used over an interval which is usually a quarter or half hour.