Working at a high enough temperature to make an efficient heat engine run would almost certainly make the PV performance worse or destroy it.

This will be low grade heat for space or water heating. Possibly applicable to chemic process or electrolysis too (heat can reduce the electricity needed to just splitting the molecule). Might be able to use the electricity to upgrade the heat using a heat pump for chemical use, although you're unlikely to beat a heliostat which is much simpler.