Hydrogen is the most abundant chemical element on Earth, and it has really wide variety of applications, starting from use in refining, petrochemical industry, steel manufacturing, and ending with use in energy production and renewable gas (hereinafter – RG) blending for gradual replacement of the natural gas in all sectors of the national economy. Being practically emission-free, if produced in sustainable way or from renewable energy sources (hereinafter – RES), hydrogen is regarded as one of the most promising energy sources for decarbonization of practically all segment of industrial and energy production. So, growing pressure of the European climate neutrality targets has triggered a special interest in production, use, storage and transportation of hydrogen – especially the green one, which can be used in at least four fundamental ways: as a basic material, a fuel, an energy carrier and an energy storage medium. In the context of sector coupling, however, hydrogen facilitates decarbonization of those industrial processes and economic sectors in which carbon dioxide (hereinafter – CO2) emissions can either not be reduced by electrification or this reduction would be minimal and linked to very high implementation costs. At the same time, development of an extensive hydrogen economy is key to the achievement of the European climate protection targets, with the European Commission’s (hereinafter – EC) Hydrogen strategy, a framework created in 2020 to develop and promote sustainable hydrogen economy in the European Union (hereinafter – EU), in its center.