Hydrogen production rate via serpentinisation reactions for natural hydrogen development

A major challenge in the societal implementation of hydrogen is the cost of hydrogen production. Against this backdrop, natural hydrogen—generated during the serpentinisation reaction, in which olivine reacts with water under high temperature and pressure—is attracting attention. As Japan possesses abundant reserves of peridotite, water and geothermal energy, there is recognised potential for hydrogen production through the injection of water into bedrock; however, a lack of fundamental data—such as the amount of hydrogen generated and the reaction rate—makes it difficult to assess the economic viability of utilising natural hydrogen. This is due not only to the difficulty of synthesising peridotite, which has a high melting point, but also to the technical challenges involved in conducting chemical reaction experiments under high-temperature, high-pressure conditions. In this study, utilising the research expertise of the Sustainable Hydrogen Research Institute, we will synthesise olivine artificially and measure the reaction rates of the chemical reactions that produce hydrogen when it reacts with water under high-temperature, high-pressure conditions. By comparing these results with the mineral and chemical compositions of natural olivine and its hydrogen production rates, we will calculate the effective recoverable reserves and economic viability of natural hydrogen.