Retrofitting Autonomous Island Power Systems

The installation of variable renewable energy sources (VRE) such as wind turbines or photovoltaic (PV) in autonomous island power systems promises high potential for fuel, cost and emission reduction. However, the volatile nature of wind and solar power limits todays maximum feasible penetration. This particularly applies for small autonomous island power systems since no load shifting can take place into neighboring grids and the existing operating reserves are significantly lower compared to large interconnected systems. In order to operate the power systems securely, the system operators have the option to limit the installation of VRE, curtail excessive amounts of electricity from VRE or by using engineering measures to increase the system's acceptance for VRE; e.g. by installation of storage capacities. This thesis provides a systematic approach for a technical and economic analysis of autonomous island power systems in terms of the optimum system retrofit to accommodate high shares of VRE.