ELECTRICITY FACT SHEET
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The magnets are on the outside (they don't move). Copper wire is around the "armature." When something spins the shaft, it causes the copper wire to "move in a magnetic field" - and electricity is produced!

A "generator" and "motor" are essentially the same thing: what you call it depends on
whether the unit is producing or using electricity.

A generator produces electricity. In a generator, something causes the shaft and armature to spin. An electric current is generated, as shown in the picture (lighting bolt). Lots of things can be used to make a shaft spin - a crank, pinwheel, windmill, bicycle, water wheel, diesel engine, jet engine, or steam turbine. They're different sizes but it's the same general idea.

A motor uses electricity. In a motor, the electricity comes in through wires attached to the positive (+) and negative (-) terminals. The electric current causes the armature and shaft to spin.  If there's just a little current and it's a small motor, it won't do very much work (i.e. it can only spin a small fan). If it's a large motor and it's using a lot of electricity, it can do a lot of work (i.e. spin a large fan very fast … or, turn the wheels of a car, bus, or truck).

Electric power plants are essentially the same thing - just LOTS BIGGER. A 180-megawatt generator at Hawaiian Electric Company's Kahe power plant on Oahu is 50 feet long, 20 feet in diameter, and weighs over 50 tons. The armature spins at 60 revolutions per second!

The different energy sources all do the same basic thing: spin something (connected to a generator made of copper wire and magnets). In a steam power plant, fuel (oil, wood, etc.) is burned to heat water into steam, which spins a turbine (connected to a generator). In a combustion turbine, burned fuel turns the turbine. In a hydropower plant, flowing water spins the turbine. The electricity is the same, regardless of energy source.

Then, the electricity flows from the generator into the powerlines and into your home, school, office, or garage (where it can charge an electric car). That’s it!
 

* The electro-mechanical approach described here (electromagnetic induction generating an alternating current) is just one way to produce electricity. There are also electrostatic, electro-chemical, photoelectric, and thermoelectric phenomena (just to name a few) which can be used to produce an electric charge or direct-current electricity. For example, you can generate an electric charge just by wearing leather-soled shoes and shuffling your feet on carpet (if the weather is dry enough). Chemical reactions can be used to produce electricity (batteries and fuel cells are based on this). Light waves can generate an electric current in certain materials (such as photovoltaic cells). A temperature difference can generate a current in a thermocouple. And there are many more examples.

Nevertheless, the electricity at your wall outlet -- that powers your toaster, blender, television, lights, etc., (or charges an electric vehicle) -- is usually produced by spinning a generator made of magnets and wires, as described above.