This hybrid tokamak / stellarator reactor could revolutionize nuclear fusion

Nuclear power covers more than 10% of global electricity needs. This is almost twice the combined electricity production from solar, wind and tidal power plants. As the world increasingly turns to renewable energy sources to combat global warming, improving nuclear power could facilitate the energy transition. Indeed, unlike fossil fuels, nuclear fission, process that allows the production of electricity in nuclear power plants, does not emit greenhouse gases. Researchers Sophie Henneberg And Gabriel Plunk proposed a new theory in their study entitled “ Compact stellarator-tokamak hybrid », published on June 4 by the American Physical Society. This theory could revolutionize the production of electricity from such infrastructures.

A hybrid design

The approach explored by the two scientists from the German Max Planck Institute for Plasma Physics consists of combining a tokamak and a stellarator. These are magnetic confinement devices that use powerful magnetic fields to compress a cloud of charged ions, also known as plasma. The goal is to release energy to trigger nuclear fusion. Depending on the nature of the confinement device, the way in which the plasma is confined will not be the same. The tokamak relies on a donut surrounded by coils of electromagnets to do the work, while stellarator-type reactors use twisted and bent coils.

A fusion reaction

You should know that unlike existing nuclear reactors, which operate using a fission reaction, these experimental devices are based on the principle of nuclear fusion. Their design presents a number of challenges which mean thatthey cannot yet be used in real conditions. In their current state, tokamaks suffer from an instability problem due to turbulence in the plasma. These phenomena are dangerous in that they can hinder the fusion process or even damage the reactor. For their part, stellarators have a fairly low efficiency due to their inability to produce a sufficient quantity of plasma.

Better stability

In order to increase the efficiency of nuclear power plants, Sophie Henneberg And Gabriel Plunk thus propose a new concept of hybrid tokamak-stellarator reactor. It turns out that this technology could help resolve the problems cited above, in particular by offering better stability. Additionally, it would reduce the amount of energy needed to trigger fusion. The study suggests keeping the donut shape of the tokamak, but using additional twisted electromagnetic loops. Called “banana coils”, these have demonstrated, during simulations, an ability to generate sufficient “twists” in magnetic fields.

A discovery that could revolutionize the design of nuclear reactors. “This is a great example of creative theory that could have a big impact on fusion energy if it leads to new research on the topic.”reacted Ben Dudson, from the Lawrence Livermore National Laboratory, which was not involved in the study. More information: journals.aps.org. What do you think of this study? I invite you to give us your opinion, your comments or point out an error in the text, click here to post a comment.