Steam turbine simply ignore engie tune up buff. This bug is beeing reported many time :
Maybe now is time to fix it, or maybe not?
Steps to Reproduce
Build a steam turbine (in debug mode), use engie tune up on it. Run steam turbine one cycle. Look in game report how many watts turbine created. Now deconstruct & construct steam turbine (without engie tune up). Run it for one cycle. Look at report. Numbers are SAME as in previous try.
This issue has not been confirmed by a developer yet.