Pepco: Megawatt U Print Page


A - C

  • Alternating Current (A.C.): Electricity constantly alternating from one direction to the other.
  • Ampere (Amp): The amount of current flowing through a conductor.
  • Atom: The smallest unit of an element or substance. It is made up of a positively charged center or nucleus surrounded by electrons.
  • Battery: In science terms, it is a device that uses chemicals to produce an electric current. In common use this relates to the items bought in shops for use in clocks, radios, etc.
  • Circuit Breaker: A switch that automatically opens an electric circuit when too much current is flowing.
  • Conductor: A material through which electric charges can travel. Materials can include metal, water, trees, moist earth and skin.
  • Current: movement or flow of electricity from one point to another.
  • Cycle: When A.C. electricity has traveled once in both directions.

D - E

  • Direct Current (D.C.): Electricity from a power source traveling only in one direction.
  • Distribution Lines: Cables that carry electricity throughout communities.
  • Electric Circuit: The path that an electric current follows.
  • Electricity: A form of energy associated with the presence and movement of electrical charges.
  • Electricity Grid: The system by which electricity is distributed from the power station to wherever it is needed. A series of cables either underground or, more commonly, held up above ground suspended from pylons are connected to substations that direct and regulate the voltage.
  • Electric Shock: Electricity going through the body. The shock can cause a person to fall to the ground or to become unconscious, depending upon the amount of electricity.
  • Electron: Negative electric charge (-1) that moves outside the nucleus of an atom.

F - O

  • Fuse: A safety device that prevents too much electricity from passing through a circuit.
  • Generator: A device that produces an electric current by spinning a coil within a magnetic field. A portable generator is often used during power outages as a "backup" electricity source.
  • Ground Wire: A device that provides the shortest, easiest path for electricity to reach the ground.
  • Insulator: A material that does not allow electricity to flow through it. The most common materials used for industrial insulators are porcelain, glass and plastics and are used in plugs, switches and protective covers for electrical devices.
  • Kilowatt-hour (kWh): The amount of electricity used and a measure by which a consumer is charged for electricity. It is the number of Kilowatts (1,000 watts) used in an hour.
  • Matter: Anything that takes up space and has mass.
  • Nucleus: The central area of an atom.
  • Ohm: Unit used to measure electrical resistance.

P - Z

  • Proton: Positive electric charge (+1) found inside a nucleus.
  • Rate: A toll, tariff, fee, price, or other charge or a combination of these items, by a public service company for public utility service.
  • Static Electricity: The build-up of electric charges (both positive and negative) on an object.
  • Substation: A facility with equipment that changes, routes, or controls the flow of electrical power. A substation in a neighborhood will lower the voltage of power and distribute it along wires to many homes.
  • Transformer: A device that increases or lowers the voltage, or pressure, of electrical power. This device enables power to be transmitted over long distances and to be used safely in homes and businesses. Near your home, a transformer lowers the voltage of electricity so that it can flow to your home.
  • Transmission Lines: Cables that carry electricity over long distances.
  • Transmission Tower: An object that holds up electrical cables carrying electricity from power stations.
  • Volt (V): A unit of measurement of the force, or pressure, available to move charges in an electrical circuit. Also referred to as voltage. Named after Alessandro Volta, an Italian scientist who developed the voltaic pile, which was the first battery.
  • Watt (W): Unit of power; measure of how much electrical power is needed for an item to work.