Auxiliary power in coal-tired power stations accounts for 7% (500 MW units) to 12% (30 MW units) of the gross generated power at the full plant load. The minimum AP varies between 4.5 and 9.0% for the same capacity range. The excessive power due to factors such as coal quality, excessive steam how, internal leakage/ingress in equipment, inefficient drives, distribution network losses, reduced power quality, ageing, etc., is quantified. An experimental study has shown that 85.7% of the AP in excess of the design value can be traced to coal quality and its indirect effects. The AP can be minimized even below the design value by operational optimization, overhaul of equipment and revamping. The paper discusses in detail the techniques for restoration of the AP to the designed value and further improvements.