A magnet, some wire, and movement
How Is Electricity Actually Made?
Every generator on Earth does one thing: it moves a magnet past wire.
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Step 1 of 5
A moving magnet pushes electrons.
Hold a magnet still by a wire and nothing happens. Move it, and the electrons in the wire are shoved sideways. The movement is essential — a still magnet makes no electricity at all.
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Step 2 of 5
More coils, more push.
One loop of wire gives a feeble push. Wind the wire into hundreds of loops and every loop adds its own, which is why a real generator is a fat spool rather than a single strand.
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Step 3 of 5
Spinning reverses it twice a turn.
As the magnet spins, each pole passes the coil in turn, so the push flips direction twice per revolution. That flipping back and forth is what alternating current is.
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Step 4 of 5
A motor is the same machine backwards.
Put electricity into a generator and the shaft turns; turn the shaft and electricity comes out. Electric cars use exactly this to recharge slightly every time they brake.
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Step 5 of 5
Something always has to do the turning.
Generators do not make energy, they convert it. Steam, falling water, wind or a diesel engine has to do the spinning — and the harder the electrical demand, the harder that thing must push.
Switch on a big appliance and the generator gets physically harder to turn. The extra electricity has to come from somewhere.
The short version
Each pole passing the coil flips the push twice a turn, which is exactly what alternating current is. Run the same machine backwards and it is a motor — and the harder the electrical demand, the harder something must push the shaft.
Try it yourself
Squeeze a wind-up torch. The resistance you feel in the handle is the electricity you are making.