Integrated energy system operation optimization with gas linepack and thermal inertia

An optimal scheduling model that can integrate the power, heat and gas networks considering the gas linepack and the thermal inertia of heating system is proposed here. By coupling the characteristics of various energy flows, the flexibility and reliability of system operation can be improved without further investment on the storage equipment. First, the storage capacity of the gas pipeline, the process of thermal system transmission and the heat storage capability at the consumer side are analysed and modelled. The associated gas linepack model, heat system thermal inertia model and primary electricity-gas-heat model are subsequently combined and simplified through incremental linearization to establish an optimal scheduling model that can be applied for the Integrated Energy System (IES) based on the characteristics of thermal inertia and gas linepack. Case studies are conducted to assess the potential of optimizing the two energy flows using the proposed optimal scheduling method and the results indicate that the IES can significantly enhance the system capability to accommodate excessive renewable energy and maintain reliable operation during peak hours.