Planning and Operation of an Interconnected Energy and Gas System: A Robust Optimization Approach

The contemporary energy sector has witnessed a notable surge in integrating renewable energy sources (RESs) within energy hubs (EHs). The intermittent characteristics inherent to RESs present a consequential challenge, notably compromising the operational flexibility of EHs. This paper proposes a two-stage adaptive robust optimization (ARO)-based interconnected energy and gas system (IPGS) with optimally sized and allocated components and energy hubs (EHs). The IPGS components and EHs are optimally sized and allocated in the first stage for optimal performance before the uncertainty realization while minimizing the investment costs. The model’s second stage incorporates optimizing operations and managing RES output uncertainty. In the second stage, the RES output uncertainty is maximized after realization while minimizing operation cost. The integration of battery energy storage systems (BESSs), thermal energy storage systems (TESSs), hydrogen storage (HSs), power-to-gas (P2G), and gas-to-power (G2P) technologies collectively serve as flexible resources that also handle uncertainty. The IPGS also incorporates a carbon capture system (CCS) to support the decarbonization of power systems. To further minimize operation costs, methane is synthesized and sold, and fuel cells are added to convert hydrogen to electricity sold to the grid. A column and constraint generation (CC&G) algorithm decomposes the ARO model using the duality theory and dual cuts. The ARO model minimizes the investment and operation costs under the worst-case realization of the uncertainties, namely, PV output, electricity demand, heat demand, and electricity and gas prices. Simulation results have demonstrated the effectiveness of the proposed method through reduced energy consumption from the grid and increased RES penetration while handling RES output intermittency. The ARO model eliminated load shedding from 31.5 MW for IEEE 24-bus and 60.3 MW for IEEE 118-bus to zero.