Electricity-hydrogen-thermal energy system capacity configuration and scheduling optimization considering multiple energy scenarios

Abstract

To address the uncertainty of renewable energy and the energy supply-demand imbalance in energy island scenarios, and to improve the adaptability of integrated energy systems to different energy scenarios in off-grid mode, this paper proposes an off-grid electricity-hydrogen-thermal energy system that incorporates heat recovery from hydrogen fuel cell. The proposed system relies on renewable energy to meet electricity, hydrogen, and thermal demands. The system integrates a thermal storage tank to recover and store waste heat from hydrogen fuel cell, supplementing thermal load demand and improving system efficiency. Additionally, we design a capacity configuration and operational optimization strategy to minimize system investment cost and optimize energy allocation. Four energy scenarios from an industrial base in Northwest China are used to validate the feasibility and adaptability of the proposed energy system and optimization method. The results show that the model achieves complete energy self-sufficiency through renewable energy and energy supply-demand balance. The proposed system enables average energy and exergy efficiency to increase by 3.15 % and 1.2 %. Compared to single storage systems, the proposed multi-type complementary approach enhances energy and exergy efficiency by at least 8.01 % and 13.54 % during severe power shortages.