The research project “Open-source modeling of the future role of renewable hydrogen in Germany and Europe” was conducted between December 2021 and November 2024 by the Technical University of Berlin and the German Institute for Economic Research (DIW Berlin) and focused on the key question of what role renewable hydrogen can play in a future climate-neutral energy system in Germany and Europe. At a time of politically ambitious hydrogen strategies at the national and European level, the project critically examined the actual potential and limitations of hydrogen use on the basis of comprehensive model-based analyses.
Methodologically, the project is based on the further development and linking of three open energy models: the hydrogen market model HydrOGEnMod, the energy system model GENeSYS-MOD (Global Energy System Model), and the electricity market model DIETER. These model extensions and model coupling enabled detailed investigation of interactions between international markets, cross-sector energy flows, and the German electricity system. All models and data sets developed were published under open licenses and thus represent a significant contribution to the open-source model landscape.
The key finding of the project is that hydrogen is an important component of decarbonization strategies, especially in sectors where direct electrification is not possible or inefficient, such as parts of industry, air and maritime transport, and long-term storage. However, it also became apparent that the use of hydrogen is associated with considerable energy losses and high costs, especially when produced by electrolysis. In many applications, the direct use of electricity, e.g., through heat pumps or battery electric vehicles, proves to be significantly more efficient and cost-effective. The studies therefore call for the targeted and economical use of hydrogen in order to enable an economically viable energy transition. However, in order to compensate for seasonal fluctuations and, in particular, to deal with extreme weather events (dark doldrums), a timely and comprehensive ramp-up of hydrogen-based long-term storage appears indispensable to accompany the expansion of fluctuating renewable energies and ultimately secure the energy transition.
In addition, the political objectives for the expansion of the hydrogen economy were viewed critically. The German government's current plans appear to be somewhat overambitious when measured against the calculated demand paths of the model analyses. The model results indicate that many of these goals are technically feasible, but economically inefficient and not optimally coordinated with other sectors of the energy transition.
Overall, the research project provides important scientific and political guidance for the targeted, efficient, and responsible use of hydrogen in the energy transition. It shows that hydrogen is not a panacea, but a valuable yet limited tool for achieving climate goals, the use of which must be carefully considered.