Selection of Synchronous Condenser technology for the Granite Substation

Vermont Electric Power Company recently commissioned a Synchronous Condenser based reactive power device in the Granite substation as part of the Northwest Vermont Reliability Project. The reactive power device consisted of four +25/−12.5 MVAr synchronous condensers and four 25MVAr shunt capacitor banks. This synchronous condenser based reactive power device was chosen over Static Var Compensators or STATCOM. This installation is significant in that it represents the first new conventional synchronous condenser provided by GE for a utility application in more than thirty years. This paper examines the needs surrounding the Granite Substation Reactive Power Device and provides a comparison of the different technologies considered. This paper also discusses both the technical and business reasons why synchronous condenser technology made the most sense in this application.