Alternating current - An electric current that reverses directions at regular intervals (typically 60 times a second); abbreviated "AC." This current found in homes.

Amps - The measurement of the flow of an electric current through a conductor.


Battery - A single electric cell, or group of connected cells, that produces a direct electric current.

Blackout - The total loss of electric power supplied by the electric company.

Brownout - A temporary reduction of voltage supplied by the electric company. Typically causes lights to dim.


Cell - A container filled with a chemical substance consisting of electrodes and electrolytes that produce an electric current by chemical action.

Charge - Electricity produced by a surplus (position) or shortage (negative) of electrons in an object.

Circuit - A complete or partial path followed by a flow of electric current.

Conductor - A substance or material that allows electrons, or electrical current, to flow through it.

Current - The flow of electricity through a conductor.


Direct current - An electric current flowing in only one direction; abbreviated "DC".

Dynamo - The first type of large generator developed for a power plant.


Electricity - A form of energy from the movement of electrons from one element to another producing a charge.

Electrolysis - The production of chemical energy by passing an electric current through a liquid called an electrolyte.

Electromagnet - A coil of wire that is wrapped around a soft iron core that is magnetized when electric current flows through it.

Electromagnetic - Objects made magnetic by an electric current.

Electron - A negatively charged atom that rotates around the nucleus of an atom.

Energy - The power for doing work.


Fuel cell - A device in which a fuel, such as hydrogen gas, is combined with oxygen to produce electricity, water, and heat.

Fuse - A safety device with a metal wire or strip that melts when the current gets too strong, cutting off the flow of the electrical current.


Generator - A machine for producing electrical current when rotated by an external driver such as a turbine.

Geothermal energy - The heat energy that is stored below the earth's surface.

Ground - A connection from an electrical circuit to the earth.

Grid - The power highways for electricity, including substations and large power lines.


Hydroelectricity - Electric energy made by the conversion of energy produced from running water.


Insulator - An object or material that does not let electricity pass through it.


Kilowatt (kW) - A unit for measuring electrical energy.

  • 1,000 watts = 1 kilowatt

Kilowatt Hour (kWh) - The use of 1,000 watts of electricity for one full hour.

  • 1 kWh = ten 100 watt bulbs all burning at the same time for one hour.
  • 10 bulbs x 100 watts each x 1 hour = 1,000 watts hours or 1kWh.


Lightning - A static electrical discharge between two clouds or between a cloud and the earth accompanied by a flash of light.

Load - The electrical device or devices that use electric power.


Magnet - An object surrounded by a magnetic field that has the natural ability to attract iron or steel.

Magnetic field - A detected force that exists around a magnet or electrical field.

Mechanical energy - The energy of motion used to perform work.

Megawatt - One million watts, or 1,000 kW.

Meter - An instrument that records or regulates the amount of something passing through it, like electricity, water, or gas.

Motor - A machine that produces motion or power for doing work.


Nuclear power - The energy produced by splitting atoms in a nuclear reactor.


ohm - The unit of measurement of the electrical resistance of a material to the flow of current.


Photovoltaic - Capable of producing a voltage when exposed to light or other radiation.

Power - The force or energy used to do work.


Radio - The sending or receiving of messages or effects, like sound, by means of electromagnetic waves through the air without a connecting wire.

Resistance - The resistance to flow of electricity through a material.


Socket - A hollow opening or cavity into which something fits, such as an electric light socket.

Solar energy - Energy produced by the action of the sun's light or heat.

Static electricity - An electrical charge that builds up due to friction between two dissimilar materials. Friction removes some electrons from one object and deposits them on the other.

Switch - A device for connecting, breaking, or changing the connections in an electrical circuit.


Thermal - Of, using, producing, or caused by heat.

Transformer - A device that raises or lowers the voltage or force of AC electricity.

Turbine-generator - A machine in which the energy of a moving fluid, such as water or steam, is converted to mechanical power that drives an electric generator.


Volt - A unit for measuring the force used to produce an electric current; the push or force that moves electric current through a conductor.


Watt - A unit for measuring electric power.

  • 1 Kilowatt = 1000 watts.
  • 1 Megawatt = 1,000,000 watts.

Wind turbine - A machine that captures the energy of the wind and transfers the motion to an electric generator shaft.