Review on recent optimization strategies for hybrid renewable energy system with hydrogen technologies: State of the art, trends and future directions

The world is currently facing a power shortage due to the inadequacy of conventional energy sources and increased energy requirements in almost all sectors of human life. To mitigate this issue, the researchers have taken the considerable interest of researchers over the past decade in enhancing energy efficiency and viability. A hybrid renewable energy system (HRES) can efficiently produce clean energy to meet energy demand. Thus, it is extensively employed to improve power system quality, reliability, and economy, rather than solely relying on non-renewable energy sources. Nevertheless, RE sources' uncertain and intermittent nature, like wind speed and solar radiation, is associated with HRES. This problem can be solved with proper optimization by coupling HRES with energy conversion and storage devices, e.g., electrolyzer, fuel cell, and hydrogen tank, which can admirably balance power generation and energy demand. The literature is rich in employing optimization techniques on HRES with hydrogen technologies (HRES-H2). However, a gap is found in the overall research progress of optimization approaches, considering HRES coupled with H2 equipment. Therefore, the current study comprehensively reviews all the optimization approaches applied in this field worldwide. Further, a text mining-based software VOSviewer is used to investigate the scientific landscape of the literature body to figure out the current trends and future scope of HRES-H2. It has been investigated that the researchers are focusing on: techno-economic optimization of HRES-H2, developing sophisticated hydrogen infrastructure to reduce the overall cost of hydrogen fuel, introducing AI-based multi-objective optimization techniques to make the HRES-H2 system more reliable and economically viable, and the impact of renewable and hydrogen technologies on the reduction of global warming. Lastly, an insightful of the current review highlighting the present shortcomings and opportunities of clean energy and hydrogen has been discussed, and suggestions are provided.