Energy management of a grid-tied residential-scale hybrid renewable generation system incorporating fuel cell and electrolyzer

• Energy management of a hybrid generation system with hydrogen storage tank is optimized.
• We improve the problem formulation to cover the dynamic behavior of both fuel cell and electrolyzer.
• We study the fluctuations of the power generated (or exchanged with local grid) and demand.
• We investigate the role of initial state of charge of the storage tank in both cost and the way that subsystems participate to supply demand.
• The price variations of stored hydrogen are also discussed.

In this paper, a new methodology has been discussed on economical power management of a grid-connected CHP system which consists of a wind turbine, photovoltaic array, polymer exchange membrane fuel cell and an electrolyzer. Hence, the paper also attempts to present the thorough modeling of energy management of the hybrid system in the form of a nonlinear optimization problem; through which offline energy management is regarded to use the available options in order to determine the role of each generator in producing heat, power and hydrogen in the system under study. In addition to this, variable tariffs of daily exchange with local grid have been taken into account in different operation conditions so as to reach real utilization requirements. Based on these facts, choosing the most suitable model for each element of the hybrid system has been considered in regard to their dynamic behavior. The proposed hybrid system is to supply the electrical and thermal demands of renewable energy laboratory of Shahid Bahonar University of Kerman (SBUK). The economical energy management is comprehensively studied and surveyed in the form of various scenarios while the hybrid system is connected to the grid.