To better support long-term energy security for Tasmania and facilitate new renewable energy development, Hydro Tasmania sought to upgrade its methods for optimizing its existing power systems and planning future expansions. This was accomplished by deploying an innovative, hybrid simulation interface between transient stability programs using Siemens PTI’s PSS®E-PSCAD Co-Simulation Add-On Module and E-Tran Plus for PSS®E from Electranix.