Energy meter

An electric meter or energy meter is a machine that measures the amount of electrical energy supplied to a residence or business. These are customers of an electric company.
The most common type is more accurately known as a (kilo) watt-hour meter or a joule meter. They may also record other variables including the time, when the electricity was used. Modern electricity meters operate by continuously measuring the instantaneous voltage and current (amperes) and finding the product of these to give direct electrical power (watts) which is then integrated against time to give energy used (joules, kilowatt-hours etc). The meters fall into two essential categories, electromechanical and electronic. The type of meter described commonly used on a single-phase AC supply. Different phase of meter configurations use additional voltage and current coils. The most general type of electricity meter is the electromechanical induction meter.

Power

Power is the rate at which work is performed or energy is transmitted or the amount of energy essential or finished for a given unit of time. It is many types of conversion Power. It is the quantity of work done or energy transferred per unit of time. Motive power is power which moves great, such as output of a motor. Electric power generation is the process of converting any form of energy to electrical energy.
Power station, a capability for generating electricity, nuclear power, the conversion of nuclear force to electricity, solar power, the translation of solar energy to electricity, wind power, the conversion of wind energy to electricity, wave power, the conversion of signal energy to electricity, tidal power, the conversion of energy of the tides energy to electricity, geothermal power, the conversion of geothermal power to electricity, hydropower, the conversion of possible or kinetic energy of water to electricity, Optical power of a lens is the opposite of its focal length, Effective radiated power in radio telecommunications is a calculate of radio station antennas.