Optimal Investment Planning of Bankable Multi-Carrier Microgrid Networks

Abstract

Multi-carrier microgrids are increasingly recognized to play a critical role in capturing the synergies between various vectors of energy, including electricity, gas, and heating/cooling systems, thereby providing an effective platform for handling the complexities associated with the dynamic interactions of the system components. While a recent, growing body of the literature has conclusively shown the effectiveness of multi-carrier microgrids in improving the business cases of localized energy solutions with high penetrations of renewables, the potential benefits associated with interconnecting neighboring multi-carrier microgrids to form networked systems are less well-explored. This is particularly important as networked multi-carrier microgrids capable of trading energy with each other during grid outages can significantly improve the resilience of the aggregated system, whilst at the same time reducing the total discounted costs. In response, this paper introduces an integrated planning framework, formulated as a mixed-integer linear programming problem, for the optimal planning of neighboring multi-carrier microgrids in the presence of demand-side flexibility resources with the aim of minimizing the total discounted cost of the networked microgrids. Based on the numerical evidence obtained from the application of the proposed method to a test-case system, the integrated planning optimization framework's effectiveness in improving the economics and resilience of a cluster of electrically coupled multi-carrier microgrids is validated. More specifically, the numerical simulations confirm the proposed model's effectiveness in a significant reduction of the under-utilized storage and dispatchable generation capacities, as well as the otherwise-curtailed non-dispatchable generations. Accordingly, the findings from this study have important implications for accelerating the transition to locally more reliable, affordable, autonomous microgrids.