Hydrogen generation by electrolysis and storage in salt caverns: Potentials, economics and Systems aspects with regard to the German energy transition

The Plan-DelyKaD project focused on an in-depth comparison of relevant electrolysis technologies, identified criteria for and selected most relevant salt cavern sites in Germany, studied business case potentials for applying hydrogen taken from storage to different end-users and engaged in identifying the future role of hydrogen from large scale storage in the German energy system. The focus of this paper is on the latter three topics above. The bottom-up investigation of most suitable salt cavern sites was used as input for a model-based analysis of microeconomic and macroeconomic aspects. The results identify dimensions and locations of possible hydrogen Storages mostly in Northern Germany with ample potential to support the integration of fluctuating renewable electricity into the German power system. The microeconomic analysis demonstrates that the most promising early business case for hydrogen energy from large scale storage is its application as a fuel for the mobility sector. From a System perspective the analysis reveals that an optimized implementation of hydrogen generation via electrolysis and storage in salt caverns will have a positive impact on the power system in terms of reduced curtailments of wind power plants and lower residual peak loads

Power-to-Hydrogen:Technical and Economic Assessment

Hydrogen generation by electrolysis is expected to play an important role as a crosslinking technology between power generation on one hand and transport and industry on the other hand. When produced by water electrolysis from renewable energies - such as solar or wind - hydrogen can directly replace fossil fuels in transport and industry, thereby helping in the integration of renewable energies in other energy sectors. The relevant technologies are either the mature alkaline water electrolysis or the newer proton exchange membrane (PEM) water electrolysis, which exhibits higher potentials for performance enhancement and cost reduction. In this presentation, the results of the study Plan-DelyKaD are presented, which is a collaborative and comprehensive effort of several institutes in Germany to evaluate the impact of power-to-hydrogen on the energy system and also discusses the possible business cases and their profitability for different uses. The study comprises a detailed analysis of the electrolysis technology with specific plant designs, the analysis of geological salt formations and the determination of specific locations for hydrogen storage in salt caverns in Germany, the investigation of business cases for different uses of hydrogen, and the impact on the whole energy system regarding the integration of renewable energies into the power sector. Due to the limited time of the presentation only the electrolysis plant design, techno-economical aspects and some important results from the energy system analysis will be discussed