Advancements and Innovations in Green Hydrogen Technologies

The only fuel, Green Hydrogen is recognized as a net zero carbon combustion product which favours environmental sustainability. It can be widely used to fulfil energy needs owing to its green impact on environment and many other advantages over the traditional fossil fuels. Green Hydrogen is becoming an inevitable alternate energy source replacing fossil fuels in industries, transportation, and also for decentralized power generation, aviation, and marine transport. Green Hydrogen is produced by an electrochemical process in which water molecules are dissociated with the help of electrolysis into hydrogen and oxygen. The potential technologies of producing Green Hydrogen are proton exchange membrane (PEM), alkaline cell, solid oxide electrolysis cells (SOEC), photo electrochemical (PEC) and solar-driven water splitting, biological and microbial electrolysis as well as hybrid technologies. These technologies have their own merits and demerits in production of Green Hydrogen in view of efficiency, cleanliness, production rate, initial cost, production cost, availability, and extent of sustainability. The present chapter provides the fundamental detailed description of these Green Hydrogen producing technologies along with their suitability and sustainability for the stated purpose. The durability of membrane, cost, and reliability are the main constraints limiting the usage of PEM for Green Hydrogen production in large scale. PEC is the potential green hydrogen producing technology and can be used to store abandoned solar energy in the form of Green Hydrogen. But the applicability of PEC is limited by its poor efficiency along with the sluggish reaction. Biological and microbial electrolysis can also be used as a suitable and sustainable Green Hydrogen producing technique as per its relevant zone of operation. The hybrid technologies are proposed by integrating multiple techniques with the objectives of enhancing Green Hydrogen production and reducing their adverse effects to enhance the sustainability of the aggregate process.