Optimization of Operation for Tourism-Oriented Island Microgrid with Combined Wind-Wave Energy and Electricity-Heat Systems

To address the prominent issues of high operating costs, low renewable energy utilization, and acute supply-demand imbalance of thermal loads during peak tourist seasons in tourism-oriented island microgrids, this paper proposes a wind-wave-electrothermal co-generation coordinated optimization model. By integrating wind energy, wave energy, and combined heat and power (CHP) systems, a multi-energy coupled system is constructed, incorporating micro gas turbines (MTs), fuel cells, and electrical/thermal energy storage. A multi-objective optimization model is established, focusing on economic objectives (minimizing operating costs) and energy utilization objectives (maximizing primary energy efficiency), while considering constraints such as power balance, equipment operational boundaries, and renewable energy fluctuations. Case studies on a typical tourism-oriented island in southeastern China demonstrate that the proposed system reduces daily operating costs by 24.2% (¥1,156.53/day vs. ¥1,524.81/day), transforms grid interaction from net consumption to net revenue generation, and significantly improves thermal load supply stability. The model effectively enhances renewable energy accommodation capacity and provides theoretical support for multi-energy coordinated dispatch in island microgrids.