What happens when fuel burns in a power station furnace?

In modern power plants, the fuel (coal, oil, gas) is burned, and the heat boils water. Steam from the boiling water turns a turbine, which turns a generator that produces the electricity.

In one natural gas-fired, jet turbine engine, the jet engine turns the first generator. The hot exhaust passes through a heat exchanger, where it turns water to steam. The expanding steam turns a STEAM turbine, which turns a SECOND generator. The waste steam is used to heat about 40 acres of greenhouses that grow tomatoes.

In everyday coal fired plants, the coal is ground to a powder, and blown into the firebox with powerful fans, where it combusts instantly.