Carbon dioxide recycling in hydrogen-based energy systems using power-to-gas facility and stochastic multi-objective optimization

With the rise of renewable energy sources (RES) due to detrimental impacts of climate change, the potential for clean energy sources such as hydrogen has gained attention. The development of various technologies, such power-to-gas (P2G) and hydrogen-based energy systems (HES), enables the integration of these systems with conventional ones in this task. This approach will help improve efficiency and resolve the substantial carbon emission problem on the demand and supply sides. This paper focuses on using hydrogen as a primary source of energy and uses wind turbine (WT) and Photovoltaic (PV) as RES. Hot- and chilled water storages besides a HTS are implemented to improve energy efficiency. Upstream grid and hydrogen markets are connected to this system to compensate for the energy deficiency in some periods. P2G functions as a carbon recycling system by reducing carbon emissions and generating extra heat from its chemical reaction for end-users. The proposed hydrogen-based energy system combined with Power-to-gas (HES-P2G) is based on stochastic programming, and takes into account various uncertainties. The nonlinearity in some restrictions is converted using the piecewise linearization technique. The epsilon-constraint method is used as a multi-objective optimization to achieve both economic and environmental goals. The fuzzy satisfying technique is used to obtain a trade-off solution between two objectives. The numerical results show the impacts of using P2G in HES in reducing carbon emission and operating cost. The current HES can significantly reduce carbon emissions; however, using P2G influences environmentally and economically. P2G will thereby cut carbon emissions by 14.2% and operating expenses by 11.7%.