In Sub-Transmission & Distribution system the significance of HT Capacitor Bank is increasing day-by-day for Shunt compensation. In West Bengal the premier power utility had taken an initiative for installation of HT Shunt Capacitor Banks at 11kV bus of 33/11kV substations. The main motto has been to improve the p.f. under Maximum demand conditions and subsequently improvement of voltage profile by reducing the huge network losses. Thus a part of today’s increasing demand can be served, keeping the same Generation & Transmission capacity and consequently, more revenue can be earned. A systematic approach for designing the shunt compensation system along with post commissioning results have been presented herewith as case study basis.