On June 18, 2026, the University of Rostock and the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) established the High Energy Density Initiative, or HEDI, in Mecklenburg-Vorpommern. The institute researches a fusion approach that Germany has not pursued in this form before: inertial confinement fusion, or ICF, using lasers. While Wendelstein 7-X in Greifswald traps plasma using massive magnets, HEDI aims to achieve the same with laser pulses fired at microscopic fuel capsules. Whether this approach reaches the goal faster or more cheaply than magnets remains open. That it can function, however, the United States proved for the first time in December 2022.
What Is Inertial Confinement Fusion?
Nuclear fusion merges light atomic nuclei into heavier ones and releases substantial energy in the process, without generating long-lived radioactive waste. The challenge: to fuse nuclei, they must be heated to millions of degrees and stabilized at that temperature. Two approaches exist.
The first approach, pursued by Wendelstein 7-X, is called magnetic confinement: the hot plasma is held in a loop by powerful magnetic fields, so it doesn't touch a wall and doesn't cool. The second principle is inertial confinement fusion: instead of holding plasma stable for hours, a small capsule filled with frozen deuterium and tritium is bombarded simultaneously from all sides by laser beams. The laser pulses compress the capsule so extremely and rapidly that fusion begins before the capsule shatters. The reaction lasts nanoseconds.
The U.S. National Ignition Facility (NIF) in Livermore, California, demonstrated in December 2022 that this principle works: the fusion energy produced exceeded the laser energy delivered. It was the first experimental proof of net energy gain in fusion research history. The NIF result noticeably shifted priorities in the global fusion community.
HEDI does not directly pursue the NIF approach, but starts one level earlier: high-energy-density physics explores states of matter under extreme pressures of megabar to gigabar. These are conditions like those in stellar and giant planet cores, existing on Earth only for fractions of a second. The founding directors, Ronald Redmer (theory) and Dominik Kraus (experiment), start with two research projects: mixtures of light elements under megabar pressures, and dynamic properties of hot dense matter under gigabar pressures.
Why Now and Why Rostock?
Mecklenburg-Vorpommern is investing 20 million euros in a research building for HEDI, to be completed by 2030. The federal government funds 90 percent of HZDR operations, Saxony ten percent. The choice of Rostock was not random: the university has a powerful laser center, and Greifswald with Wendelstein 7-X lies 110 kilometers away. HEDI and Wendelstein thereby complement each other as two fusion approaches in the same state, enabling shared infrastructure and personnel.
Cooperation partners include the European XFEL near Hamburg, one of the world's most powerful X-ray laser sources, providing essential infrastructure for high-energy-density experiments. HEDI also cooperates with Marvel Fusion, a Munich startup bringing private capital into ICF research. The federal program "Fusion 2040" frames the initiative as industrial policy: basic research aimed at preparing commercial fusion power plants by 2040.
Germany in the Global Fusion Race
The United States currently sets the standard. After its 2022 breakthrough, NIF significantly increased funding for ICF commercial research. Private companies such as Commonwealth Fusion Systems in Massachusetts and Focused Energy in Austin are simultaneously pursuing different fusion approaches with billion-dollar investments. Focused Energy is notably a German-American company pursuing the ICF approach with offices in Darmstadt and Austin.
China invests in both fusion pathways: in the tokamak sector, EAST is running, and the more ambitious CFETR plans to exceed Wendelstein and ITER in scale. In the laser sector, China operates multiple ICF facilities, information about whose progress emerges only sporadically. Germany's commitment to researching both magnetic confinement and inertial fusion at least closes a conceptual gap against other leading research nations.
The decisive boundary lies between experiment and power plant. NIF has generated net energy, but the overall system's efficiency remains far below a commercial power plant. The laser light itself consumes more energy than it produces. HEDI, too, researches physical fundamentals first; no power plant is on the schedule by 2030. Kraus and Redmer are scientists, not utility operators. The gap between a record experiment and an electricity bill persists.
First Measurements: Earliest 2028
The HEDI research building is planned for completion by 2030. First experiments will be possible earlier in existing HZDR laboratories, at the European XFEL, and at Wendelstein 7-X, the founding directors estimate. The HZDR expects concrete results from HEDI projects no earlier than 2028, when the first junior research teams complete their measurement campaigns. Wendelstein 7-X plans for 2026 or 2027 to demonstrate 30-minute plasma, which would serve as proof that magnetic confinement functions in sustained operation. Both milestones together would position Germany favorably for the next step: the decision on which fusion approach the federal government prefers for a demonstration power plant.