Given the task definition and input, reply with output. In this task, you are given a paragraph, and your job is to generate comma-separated entities present in the given paragraph. Generate entities from a given passage in such a way that (i) they are present in the paragraph, (ii) they are non-duplicate, (iii) they underwent a state change during the process. Avoid creating entities that (i) aren't present in the process paragraph and (ii) aren't significant. 

The coal is pulverized to a very fine powder. The coal powder is mixed with hot air and blown into the firebox of the boiler. Water pumped through pipes inside the boiler is turned into steam by the heat. The pressure of the steam pushing against a series of giant blades turns the turbine shaft. Turbine shaft is connected to the shaft of the generator. The magnets inside the generator spin within wire coils to produce electricity. 

coal powder ,water ,steam ,turbine shaft ,magnets ,electricity 