New milestones in magnetic fusion power

Part of Today in the Lab – Tomorrow in Energy?

Today in the Lab – Tomorrow in Energy? shines a spotlight on research projects under development in the Technology Collaboration Programmes (TCPs). Learn more about the initiative, read the launch commentary, or explore the TCPs.

Bringing the stellarator concept to maturity

What is the aim of this project?

Wendelstein 7-X is one of the largest nuclear fusion devices worldwide and the most advanced of the stellarator type. Its objective is to bring the stellarator concept to maturity in a power plant that generates electricity by using heat from fusing hydrogen nuclei.

How could this technology be explained to a high school student?

Nuclear fusion produces energy using the heat that is released when hydrogen nuclei – transformed into the plasma state of matter – fuse to form helium. The stellarator, one of two types of magnetic confinement fusion reactors under development today, is based on an optimised magnetic field that protects the hot plasma from the cold wall. The magnetic field is formed by complex superconducting magnetic field coils. These coils create a ring-shaped, twisted magnetic “cage” in which a few milligrams of hydrogen gas will be heated to temperatures of up to 100 million°C, transforming it into plasma. With plasma pulses potentially lasting up to 30 minutes, Wendelstein 7-X aims to demonstrate the essential stellarator property: continuous operation with stable high performance.

What is the value of this project for society?

  • advances applications of physics for fusion power
  • enhances the effectiveness and productivity of worldwide fusion research
  • paves the way for the production of abundant, clean and sustainable energy

At what stage of development is this project?

The project was approved in 1996 and first plasma produced in December 2015. After three successful operation phases, comprehensive upgrading of the machine began at the end of 2018. In 2022, plasma operation is expected to resume with the necessary installations for 30-minute high-performance plasma pulses.

What government policies could bring this from the lab to the market?

  • Programmes to enhance public-private collaboration on key technologies like high-temperature superconductors, high-performance materials, additive manufacturing and big data science.
  • Stable, long-term institutional funding of large fusion devices to enable continuous development of science and technology and to bring the fusion concept to technological maturity.
  • Support to spur innovation and advance the competitiveness of involved industries by allowing them to go to technological limits as required to master high heat fluxes, strong forces, magnetic fields and extremely high integration densities

View into the plasma vessel of the Wendelstein 7-X. It is adapted to the complex shape of the magnetic field generated by 50 superconducting coils. Photo source: IPP, Bernhard Ludewig

Video presentation


  • Max Planck Institute for Plasma Physics, Germany
  • TCP partners in the European Commission, Japan, Russia, Ukraine and the United States


  • Federal Republic of Germany
  • Mecklenburg-Western Pomerania
  • European Union

Partners and funders

About the Technology Collaboration Programme on Stellarators and Heliotrons (SH TCP)

Established in 1985, the objective of the SH TCP is to improve the physics base of stellarator and heliotron technologies and to enhance the effectiveness and productivity of research and development efforts by strengthening co-operation among the member countries.