Nuclear fusion has been researched into for decades. If we could manage to tame them and let them run in a controlled manner in a power plant, we would have tapped into the primordial fire of the billions and billions of stars in the universe. What is the current state of affairs?
The astrophysicist Josef M. Gaßner has this to saypublished a YouTube video. With his help and some additional information from Professor Harald Lesch, we discuss where nuclear fusion stands at the end of the first quarter of the 21st century.
We structure oursQuick introduction to nuclear fusion
as follows:
- What concepts are there for using nuclear fusion to generate electricity?
- Where does Josef M. Gaßner see the core challenges?
- Does nuclear fusion produce nuclear waste?
- Can fusion reactors explode?
- Do we have enough fuel?
- Can it be estimated when the first nuclear fusion power plants will come online?
What concepts are there for using nuclear fusion to generate electricity?
At theNuclear fissionan atomic nucleus is broken down into two or more smaller ones. In doing so, he releases energy. For this to happen, the starting core must be sufficiently heavy - for example uranium. This is the basis of all today's nuclear power plants.
KernfusionOn the other hand, two light atoms fuse to form a heavier one. We use hydrogen and turn two into one helium atom. Energy is primarily released in the form of neutrons. During fusion, plasma is created (fourth basic state of matter: solid, liquid, gaseous, plasma).
We (usually) have to use heat to do this. The sun does it with pressure, which we can't exert on a sustained basis. We currently know the following main ways to achieve a merger:
- Stellarator or Tokamak:Electric current is used to generate magnetic fields that keep a plasma suspended inside an annular reaction chamber.
- Inertial Fusion (bullet or laser):Tiny amounts of hydrogen are fused either by lasers or the impact of a projectile. When the bullet hits, an extremely large amount of pressure is created for a short time, not constant as with the sun. But whether this way or through lasers: We then essentially collect the energy from exploding miniature hydrogen bombs.
The electrical power that we can all use is usually generated in the classic way using turbines driven by steam. This is created by heating water using the energy released during fusion.
You can find out more about the basic principles of nuclear fusion and, in particular, the inertial function in.
Where does Josef M. Gaßner see the core challenges?
Aside from the countless individual challenges depending on the type of reactor, the astrophysicist outlines three core areas that, in his opinion, generally delay the construction of the first power plant:
- More in than out:Currently, even in the laboratory, it has not yet been possible to generate electricity. We always use more energy than we can tap into.
- Nonlinearity:When it comes to nuclear fusion, room-sized systems in the laboratory cannot simply be scaled up and expanded to those larger than football fields. The physics is very complex. On a small scale it may work for a short period of time. But continuous operation to produce electricity for baseload supply is a completely different league. Almost like senior amateurs against A world champions in a sport of your choice.
- International collaborations increase complexity:Based on theflagship tokamak reactor ITER, which is created in southern France, Gaßner illustrates another point. When dozens of nations work on a project, that is politically and socially fantastic, but it extremely inflates the bureaucracy and necessary agreements. The reason: everyone wants to generate as much knowledge as possible to build their own power plants.
Most other research reactors built under simpler conditions do not currently reach the scales of ITER. And even it is far from suitable for operational use. In the future, we want to use what we have learned to build humanity's first large-scale fusion reactor, called DEMO (viaMax-Planck-Institut).
Does nuclear fusion produce nuclear waste?
Yes, nuclear fusion produces radiant material. However, according to Gaßner, the half-lives are far shorter than those of classic nuclear waste. This makes handling and, above all, storage easier.
Can fusion reactors explode?
No, switching off fusion processes is more direct: Imagine it as turning off the pipe on a gas stove. The fusion plasma and thus the energy release expire immediately. With fission power plants, problems can still arise despite switching off electricity production. Nuclear fission occurs on its own and in most cases has to be actively inhibited. Fusion, on the other hand, requires a supply of electrical energy for the magnetic fields or fuel that can be bombarded.
Do we have enough fuel?
Yes, because it swims in our oceans in virtually infinite quantities. Hydrogen isotopes such as deuterium and tritium are primarily fused. Like Professor Harald Lesch as a colleague of Josef M. Gaßner in an older oneYouTube-Videoexplains: There is as much energy usable through fusion in one liter of seawater as there is in a barrel of oil, around 159 liters.
Can it be estimated when the first nuclear fusion power plants will come online?
Josef M. Gaßner has given up hope of drawing nuclear fusion electricity from the socket: "I won't live to see it." He will celebrate his 59th birthday in 2025. This is in line with Harald Lesch's estimates: According to him, commercial nuclear fusion is at least 30 years away.
Gaßner further states: Once they are built, they remain reserved for nations with established high-tech infrastructure, research and development. Without this basis they will not be able to operate because fusion power plants are complex systems.
