Retrofit of a Resilient Hybrid Power System for a Remote Island

A mathematical model is presented for the synthesis and retrofit of a resilient electricity network for a remote island. The current electricity network uses diesel fuel power plant as the main power source and will be supplemented with wind turbines in this study, where part or all of the electricity generated from the wind turbines is used to pump water into the upper reservoir for providing the smooth hydraulic electricity. The role of this pumped hydro storage (PHS) is to support the hybrid power system (HPS) and to smooth the unstable and uncontrollable renewable power sources. Based on the proposed superstructures for the hybrid power system, the hybrid power system retrofit problem is formulated as a mixed-integer linear program (MILP) with power losses during the allocation of power generated from power supplies to power loads or PHS. With the given collection of data for the island, the minimum electricity supply of the traditional power plant, the minimum numbers of renewable energy equipment, the minimum capacity required and the minimum power generation of PHS can be determined through a four-step optimisation approach. A practical case study is solved using historical data to illustrate the proposed approach.