DTU is a popular destination for Denmark's third-year high school students when they have to write their mandatory, multidisciplinary assignments. The university grants the students access to experts in a wide range of subject areas as well as the opportunity to carry out exercises that they cannot do at secondary school or at home.
For example, DTU's fusion reactor, NORTH, was particularly well-visited in the spring of 2023. A total of 30 students on the STX programme (Higher General Examination Programme) experienced the reactor up close and gathered knowledge and data in order to write about fusion energy in their specialized study project (SRP). In this article, we follow a group of 10 students who visited NORTH on 1 March.
NORTH is also called a tokamak, and in larger versions of this type of machine, you can create fusion processes, i.e., melt atomic nuclei together. The process is identical to the one constantly taking place in the interior of the Sun, and DTU’s tokamak is of the same type as the fusion power plants of the future.
Fusion is the reverse of the process in conventional nuclear power plants. Here, the atomic nuclei are cleaved in a process called fission.
A sustainable energy source
NORTH is too small to produce fusion energy, and increasingly large tokamaks are therefore being built, such as ITER in the South of France, which is currently scheduled to be ready for use in 2025. In turn, NORTH’s size makes it possible to carry out many tests without using huge amounts of energy, making it attractive for researchers.
During their visit, the high school students were first introduced to fusion energy, after which they were ready to enter the room that houses NORTH. Here they measured the temperature and density of electrons in a plasma magnetically enclosed in the small tokamak.
The plasma examined by the students is formed by heating gas—in this case hydrogen—to an extremely high temperature using microwaves. In larger and hotter tokamaks, this causes the atomic nuclei to fuse to form the gas helium. The fusion process releases large amounts of energy, making fusion a sustainable energy source with huge potential.
A large tokamak contains plasma that can reach a temperature of well over 100 million degrees Celsius. In comparison, the temperature at the Sun’s core is approximately 15 million degrees Celsius.
In the future fusion power plants, we need to create a fusion plasma with as high a temperature and density as possible if the fusion process is to occur often enough to produce a surplus of energy. We are not at that stage yet, but with the help of NORTH, DTU's researchers are continuously learning more about what it takes to create such a plasma.
A future as a fusion researcher
Falke Geels, who graduated from Roskilde Gymnasium this summer, had just read an article about a major breakthrough in fusion energy when he signed up for the SRP-assignment at DTU Physics.
“Fusion energy is something I’m interested in right now, but I’m also participating in order to figure out whether I want to study this at DTU and conduct research in this field in the long term,” he explains.