Fusion

Kernfusion
© shutterstock.
Kernfusion

Fusion technology promises nothing less than clean and sustainable energy for future generations. For this reason, research institutes around the world are working intensively on concepts for future nuclear fusion reactors – which do not have the risks associated with nuclear fission.

In a fusion reactor, light atoms such as hydrogen collide and fuse together to create heavier atoms such as helium, releasing huge amounts of energy in the process. In the sun, the fusion process is sustained by the enormous mass, gravitational force and high temperatures. In order to reproduce fusion on Earth, the gases must be heated to extremely high temperatures of around 150 million degrees Celsius. At this temperature, the gas transforms into a plasma, a prerequisite for nuclear fusion.

There are different approaches to heating a plasma to such temperatures. The most promising are magnetic fusion and inertial confinement fusion. In magnetic fusion, strong magnetic fields stabilize the plasma in a magnetically confined space. These magnetic fields also generate the temperatures and pressures required for fusion to take place. Inertial fusion is different; here, a fuel in fusion targets is compressed to an extreme and heated to the required temperature by a very rapid, external supply of energy.

Inertial fusion or inertial confinement

Inertial confinement fusion relies on the use of high-energy laser beams to compress a small fuel capsule. This compression leads to extremely high temperatures and pressures inside the capsule, which triggers the fusion of the hydrogen isotopes it contains.

Thirty institutes of the Fraunhofer-Gesellschaft are participating in a strategic process aimed at developing inertial fusion energy into a safe, carbon-free energy source of the future. Fraunhofer ILT is contributing its laser technology expertise not only to national, but also to international networks and collaborations, such as with the Lawrence Livermore National Laboratory LLNL in California.

High energy laser

The inertial confinement fusion laser systems consist of complex arrays of high-power lasers that must be precisely synchronized to generate a laser pulse of extreme intensity of over 2 million joules of UV light. At the same time, these laser pulses must be precisely controlled to ensure that they hit the fuel capsule with a mixture of hydrogen isotopes evenly and at the highest precision. In addition, the laser systems must be robust enough to withstand even the extreme stresses associated with generating these intense laser pulses.

The path from the laboratory to the power plant

In a funded joint research project with a consortium from industry and research, Fraunhofer ILT is developing the basic principles and framework conditions for the commercial use of inertial fusion.

The consortium aims to find efficient and practicable ways to further develop the technology in a targeted manner and use it commercially. They will start by developing suitable optics and laser beam sources, which must be as resilient and affordable as possible, through generating solutions for high-frequency fuel supply, to rapidly removing and using the waste heat generated sensibly.

Use our infrastructure

 

Further information about our laboratories