What supplies megawatts?

Answer 1

Megawatts are a unit of power. The question has many answers depending on from which layer you're asking.

Given the category, I assume you mean megawatts as transmitted through electricity. Electricity is generated at a power plant, usually by burning some type of fuel (e.g. coal or nuclear rods).

The heat produced by the fuel boils water to produce steam. The pressure from the steam will spin a turbine. As the turbine rotates, it moves magnets around a metal wire. The movement of the magnets around the wire generates, in the wire, a current of electrons. This current is what we call electricity. Roughly, a megawatt, is an amount of electricity at any given point in time.

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