Clean (green and blue) hydrogen and synthesis fuels, which do not have a carbon footprint or emit much lower amounts of greenhouse gases, especially carbon dioxide, when burned, offer promising solutions for sustainability and environmental impacts in the energy sector.
Green hydrogen is an energy carrier obtained by the decomposition of water by electrolysis. During the electrolysis process, water molecules are decomposed into hydrogen and oxygen gases by using electricity obtained from renewable energy sources (wind, sun, etc.). The resulting hydrogen can be used in many fields such as electricity generation, transportation sector, industrial processes and long-term and flexible energy storage. Blue hydrogen, on the other hand, is produced in converters from fossil fuels, and the process waste carbon dioxide is kept without being released into the atmosphere and stored permanently by various means. Hydrogen fuel cells also draw attention as a technology in which hydrogen reacts with oxygen and produces useful energy (electricity) with a much higher efficiency than conventional internal combustion engines.
Synthesis clean fuels, on the other hand, refer to fuels formed by recombining hydrogen with nitrogen or carbon, and are also called LOHC (liquid organic hydrogen carriers). Examples of these are products such as methanol and ammonia, which are used both as fuel and as industrial and agricultural raw materials. In the case of combustion or use in processes, there is either no carbon dioxide emission (in the case of Ammonia) or much lower rates compared to fossil fuels (in the case of Methanol). These organic synthesis fuels can be easily integrated both as an existing fuel and as an input to industrial and agricultural infrastructure.
Clean hydrogen and synthesis fuels, which do not have a carbon footprint or carry much lower rates, bring many advantages. First, it reduces dependency on fossil fuels and increases diversity in the energy sector by using the same infrastructure and existing technologies, without requiring additional processes and investments. At the same time, by increasing long-term and available energy storage capacity, it largely offsets the irregularities brought about by intermittent renewable energy generation systems and provides sustainability (continuity and stability) and flexibility in energy supply. It is one of the most important steps in taking the final steps towards the targeted zero carbon emission energy system.
However, there are obstacles to be overcome for the widespread adoption of clean hydrogen and its synthesis organic fuels, and its dissemination requires support and willpower. Among these, issues such as reducing production costs, developing transmission (maritime or pipeline) infrastructures, making certification processes simple and clear and validating them on an international scale are at the forefront. In order to achieve the goals, providing policy supports and incentives in parallel with technological advances and developing regional and global cooperation will play important roles.