The relentlessly rising demand for computing power, especially for HPC and AI, is driving rapid growth in both the number and scale of supercomputers. This expansion comes with a sharp increase in energy consumption (for example, to approximately 17 MW for the Exascale system JUPITER at JSC), posing significant sustainability challenges for HPC centres.
As an representative example German HPC centres have collaborated to identify the innovations required to meet sustainability and energy-efficiency goals, shaped by high energy costs, national policies, and environmental commitments. Their work highlights a range of measures that can guide HPC toward a more energy-efficient future. (https://doi.org/10.3389/fhpcp.2025.1520207)
Involved in the review report are: Deutsches Klimarechenzentrum (DKRZ), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), High-Performance Computing Centre Stuttgart (HLRS), Jülich Supercomputing Centre (JSC), Karlsruhe Institute of Technology (KIT), Leibniz Supercomputing Centre (LRZ), Max Planck Computing and Data Facility (MPCDF) and Technische Universität Dresden (TUD).
All German HPC sites mentioned above together host a total of about 20 machines ranking places 4 (JUPITER Booster at JSC) to 493 (AlphaCentauri at TUD) in the Top 500 list (status November 2025), and 2 out of the 10 most energy-efficient systems in the Green 500 list (status November 2025).