Influencing factors of water electrolysis electrical efficiency

As a promising method of hydrogen production by utilizing renewable energy sources for future, water electrolysis is one of the favorite fields of the study and scientific experiment for many researchers all around the world. One of the most popular related research areas is the efficiency enhancement of the process by the means of reducing the electric power consumption in electrolysers. Regarding to different effective factors related to this issue, many efforts have been done to reach elevated levels of current densities by maintaining or even reducing the electrolysis cell voltage. According to this matter, recommendations could be given for reaching higher process efficiencies. This paper analyzes the factors with an influence on water electrolysis efficiency by studying available verified information in the electrical, electrochemical, chemical, thermodynamics and fluid mechanics fields.