Optimal Energy Flow of integrated energy systems with hydrogen economy considerations

This paper investigates the formulation of a general optimal energy flow (OEF) problem for integrated energy systems, paying particular attention to "hydrogen economy" issues, i.e. production, distribution and utilization of hydrogen, as well as considering the impact of energy storage devices. Based on the concept of energy hubs, the optimal conversion and transmission of multiple energy sources and energy carriers, in particular natural gas, electricity, district heat and hydrogen, considering energy storage devices are discussed. A 3 energy-hub system with electricity, gas, heat and hydrogen production, distribution, demand and storage capabilities is used to illustrate some of the proposed concepts and analysis techniques. The results illustrate some of the advantages of combining different energy sources and carriers, particularly if hydrogen is considered as an integral part of the energy system, given its storage characteristics.