The beam engine was not what you’d recognize today as a steam engine. What did the work was not steam pressure, but atmospheric pressure. Low pressure steam was allowed into the cylinder and then condensed, forming a vacuum, and atmospheric pressure drove the piston. read more
A steam engine is a heat engine that performs mechanical work using steam as its working fluid. Unless you are specifically referring to steam railway locomotives, a particular application of the steam engine, then yes steam engines are widely used as the most common worldwide means of producing electric power. read more