A Alternating current: An electric current that reverses directions at regular intervals (typically 60 times per second); abbreviated "AC." This is the current usually found in homes.
Ampere, Amps: The measurement of the flow of an electric current through a conductor.
Anemometer: An instrument for measuring wind speed and velocity.

B Battery: A single electric cell, or group of connected cells, that produces a direct electric current.
Biomass: Organic materials such as plants and animal waste that can be used as a fuel.
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.

C Cell: A container filled with a chemical substance consisting of electrodes and electrolytes that produces an electric current by chemical action.
Charge: Electricity produced by a surplus (positive) 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.

D Direct current: An electric current flowing in only one direction; abbreviated "DC".
Dynamo: The first type of large generator developed for a power plant.

E Electricity: A form of energy created by the movement of electrons creating a current. It occurs naturally in the form of lightning, or can be produced with a generator.
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.
Electron: A negatively charged particle that rotates around the nucleus of an atom.
Energy: The power for doing work.

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

G 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.

H Hydroelectricity: Electric energy made by the conversion of energy produced from running or falling water.

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

K Kilowatt (kW): A unit for measuring electrical energy.
1,000 watts = 1 kilowatt

L Lightning: A static electrical discharge between two clouds or between a cloud and the earth accompanied by a flash of light.
Load: The power output of a generator or power plant. Also, the resistance of a device to which power is delivered.

M Magnet: An object surrounded by a magnetic field that has the ability to attract iron or steel.
Magnetic field: A detected force that exists around a magnet.
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.

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

O Ohms: The unit of measurement of the electrical resistance of a material to the flow of current.

P Photosynthesis: The process in which green plants absorb the energy of sunlight to produce carbohydrates and oxygen from carbon dioxide and water in the presence of chlorophyll.
Photovoltaic: Capable of producing a voltage when exposed to light or other electromagnetic radiation.
The capacity, force, or energy used to do work.

R 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 opposition of a body or substance to energy or electric current passing through.

S 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.

T 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 wind, water, or steam, is converted to mechanical power that drives an electric generator.

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

W Watt: A unit for measuring electric power.
1 Kilowatt = 1000 watts.
1 Megawatt = 1,000,000 watts.