The term that the original poster didn’t include is “Cogeneration” [0]. Another use case would be desalination in areas without an adequate supply of freshwater.
Ya, I get that, it just doesn’t seem to be always the case that you’d find something to do with the heat, especially given proximity of the coal plant to places that could use it. It wouldn’t seem to work well for Australia, at first glance (no serious heating needs, no desalination plants).
[0] https://en.m.wikipedia.org/wiki/Cogeneration