Steam engine
Steam energy is a form of thermal energy that is harnessed by using steam to power turbines that generate electricity. It is commonly used in power plants that rely on steam as a source of energy to produce electricity.
water
A steam engine uses a hydrocarbon based fuel source. The combustion of the fuel releases the chemical energy in the bonds in the form of thermal energy.
The energy source in a steam engine is the heat source that converts water into steam thus creating pressure. The heat source itself can be a coal, wood, gas or petroleum burner but can also be something different like a solar panel or a nuclear reactor (most nuclear reactors are themselves steam engines-generators).
Steam engine
the steam engine
the steam engine
the steam engine
The function of the steam engine is to convert heat energy into motive power, mechanical energy. A boiler generates steam by the application of heat, that steam is then expanded (losing its heat energy) into a steam engine which moves a load (locomotive, line shaft, pump, machine, generator, etc.).
steam engine
Other to coal I suppose you mean. Burning of any fuel like oil, wood, etc. Nuclear reactors. I suspect solar energy would make steam. It would be possible to use natural steam from deep in the ground.