What are nuclear fusion hazards

Nuclear fusion - by no means that unproblematic!

The sun is a huge natural fusion reactor. Enormous pressure and extreme heat in the center of the sun are prerequisites for the fact that - to put it very simply - hydrogen atom nuclei fuse into helium atom nuclei, whereby one helium atom is formed from every two hydrogen atoms. During this process, heat is released.

For decades, scientists and technicians have endeavored to imitate this type of energy generation on earth as well. An artificial fusion with a positive energy balance has only succeeded in an uncontrolled manner in the hydrogen bomb. Controlled nuclear fusion in fusion power plants is - as is well known in specialist circles - associated with enormous risks.

Once upon a time, euphoric expectations were placed on the nuclear fission of today's nuclear power plants. Hardly anyone spoke of dangers. Today the same mistake is being made again: It is pretended that the risks of controlled nuclear fusion are manageable and that our energy problems can be solved with this technology without great dangers.

Therefore, some problems and risks associated with the operation of nuclear fusion power plants should be pointed out here:

- Nuclear fusion is associated with extreme neutron radiation. The reactor must therefore be surrounded by a protective jacket that intercepts the radiation. However, this radiation damages the material of the jacket and also causes induced radioactivity. Therefore, the parts of the jacket must be replaced at certain time intervals. This means that similar problematic substances arise in nuclear fusion power plants as in nuclear fission power plants: highly active nuclear waste.

- Hydrogen is a highly explosive gas. The hydrogen atoms are the smallest atoms there are and therefore "slip" (diffuse) in small quantities even through thick steel walls. So of course the radioactive hydrogen atoms.

- Hydrogen exists in nature in the form of three isotopes. Two are stable: "normal" hydrogen H1 (light hydrogen, "protium", 99.985% share of natural hydrogen) and heavy hydrogen H2 ("deuterium" D, 0.015% share of natural hydrogen). Heavy hydrogen D3, also called "tritium" (T), is the third isotope. It is unstable (radioactive) and only occurs in the smallest traces in nature (10-15 %). In the fusion reactor you are dealing with deuterium and tritium. Tritium, because it practically does not occur in nature, has to be "incubated" from lithium with the help of neutron radiation. Tritium is a beta emitter with a half-life of 12,323 years.

- An extremely high temperature (over 100 million degrees) is a prerequisite for successful nuclear fusion in a fusion reactor. The fact that this is associated with problems and dangers does not need any explanation. In the interior of the sun, however, there is extreme pressure (350 million times greater than in the earth's atmosphere near the ground), so that nuclear fusion already takes place at 16 million degrees.

- The use of the alkali metal lithium, which is used in a molten state, poses a further risk. As already mentioned, tritium is produced from lithium. At the same time, however, it also serves as a means of transporting the heat from the reactor to the boiler ("coolant"). This metal is extremely reactive and must therefore never come into contact with water (violent reactions, risk of fire).

"Imitating the sun" sounds very seductive, of course. When supporters of nuclear fusion admit that there are still decisive questions unanswered with regard to the peaceful use of fusion, the little word "still" arouses hope and justifies generous state subsidies, so to speak. It would be better to keep your hands off nuclear fusion in order to save yourself a lot of the following practical constraints and rather to generously support research in the fields of renewable energy and energy efficiency.