Renewable Hydrogen Production Steps Up Wastewater Treatment under Low-carbon Electricity Sources - A Call Forth Approach

Switching to renewable resources for hydrogen production is essential. Present hydrogen resources such as coal, oil, and natural gas are depleted and rapidly moving to a dead state, and they possess a high carbon footprint. Wastewater is a promising avenue in searching for a renewable hydrogen production resource. Profuse techniques are preferred for hydrogen production. Among them, electrolysis is great with wastewater against biological processes by hydrogen purity. Present obstacles behind the process are conversion efficiency, intensive energy, and cost. This review starts with hydrogen demand, wastewater availability, and their H2 potential, then illustrates the three main types of electrolysis. The main section highlights renewable energy-assisted electrolysis because of its low carbon footprint and zero emission potential for various water electrolysis. High-temperature steam solid oxide electrolysis is a viable option for future scaling due to the versatile adoption of photo, electric, and thermal energy. A glance at some effective aspirations to large-scale H2 economics such as co-generation, biomass utilization, Microbial electrolysis, waste to low-cost green electrode, Carbon dioxide hydrogenation, and minerals recovery. This study gives a broader view of facing challenges via versatile future perspectives to eliminate the obstacles above. renewable green H2 along with a low carbon footprint and cost potential to forward the large-scale wastewater electrolysis H2 production, in addition to preserving the environment from wastewater and fossil fuel. Geographical and seasonal availability constraints are unavoidable; therefore, energy storage and coupling of power sources is essential to attain consistent supply. The lack of regulations and policies supporting the development and adoption of these technologies did not reduce the gap between research and implementation. Life cycle assessment of this electrolysis process is rarely available, so we need to focus on the natural effect of this process on the environment.