The largest nuclear project in history

International physicists will build the largest 5 billion euro factory ever to produce energy through nuclear fusion. Thanks to it, only three bottles of water can be supplied to one family throughout the year.

For half a century many physicists around the world have been trying to find ways to generate electricity and heat from nuclear fusion, although public opinion no longer hopes that their efforts will bring something. useful. But by the time almost no one is interested in their work, plasma physicists have achieved amazing progress.

Günther Hasinger, Director of Max Planck Institute for Plasma Physics (IPP) at Garching (Germany), said: "We are approaching a breakthrough. If there is an Apollo program for nuclear synthesis, we have "It's possible to build a reactor that supplies electricity and heat right from the beginning of the new millennium. Right now we only lack the money needed for such a large reactor."

Nuclear fusion occurs within the stars. Under a terrible pressure, mild hydrogen (H) nuclei synthesize into Helium (He). The energy released in that process was so great that it was almost unimaginable. For billions of years, nuclear fusion provides light and heat for life on earth. But people cannot simply simulate the sun in a laboratory on the globe.

Plasma chamber of fusion reactor at Max Planck Institute in Garching.Photo: Spiegel.

No machine on earth has the ability to create a high pressure like the stars. Scientists try to compensate for this flaw by heating up the charged hydrogen gas stream to 100 million degrees Celsius to create a temperature greater than the sun's surface. But controlling plasma to form is difficult. One has to use a lot of powerful magnets to keep it suspended in the reactor, because once it touches the kiln it will become impurities and cool, causing the nuclear synthesis to stop immediately.

So far, since the plasma insulation is not good enough, the fusion reaction in the lab releases too little energy. As a result, the reactions do not have enough energy to maintain the synthesis themselves. If continuous heat is not supplied from the outside, the process of fusing the seed will die. But there is still one solution: Build a really big nuclear synthesizer.

"If we increase the volume of the plasma, the heat loss will automatically decrease," explained Hasinger.

To prove that nuclear fusion is actually capable of producing energy, scientists plan to build a giant machine. In the next few months a nuclear synthesis plant called "Iter" will be built at the Cadarache nuclear research center in southern France. According to calculations, the experimental furnace with a capacity of 500 MW will provide 10 times the amount of energy it takes to heat its plasma. Hasinger said: "In 10 to 12 years, when Iter starts, no one will doubt whether this is a good investment."

The EU also has the United States, China, India, Japan and South Korea to participate in this 5 billion Euro project. Right now people have predicted that the cost for Iter will increase by another 30%.

In a nuclear fusion, the mass is transformed into energy. So a 1,000 MW reactor requires very little fuel: 1 kilogram of hydrogen can provide electricity equivalent to 11,000 tons of coal.

Heavy hydrogen (ie deuterium) can be produced in almost endless mass from seawater. People will no longer depend on fossil fuels such as oil or gas. Unlike a thermal power plant, nuclear fusion reactors do not release any toxic emissions into the atmosphere.

The risk of risk is also almost nonexistent, as the synthesis process will stop automatically once there is a minor incident. Radioactive waste formed when firing high-energy neutrons into the inner wall of the reactor. Only after about 100 years, their radioactivity is so weak that it cannot be dangerous.

Reactor (pictured) at the Cadarache Nuclear Research Center in South France.Photo: Spiegel.

Triti fuel also has similar safety. This isotope of H has weak radioactivity, half-life is only about 12.3 years. In the Iter reactor, triti will be mixed into the plasma of deuterium to improve energy efficiency.

A few weeks ago, the physicists at Garching discovered a new way to improve the synthesis process. Through many unpublished experiments, they found that mixing nitrogen (N) into the mixture was very effective.

Instead of cooling down due to impurities, the temperature of the plasma in the reactor increased - and at the same time the energy released also doubled. "We have not really understood this phenomenon, but it is clear that N increases insulation ," Hasinger said.

The biggest challenge for researchers is to build a better magnetic trap to keep plasma. All normal fusion reactors have a structural weakness: Many electrical impulses are fired at electrically charged H gas to create a magnetic field that holds the plasma, and also makes it more difficult to control.

"We force the plasma to build its own cell with electrical impulses. It reacts by nestling in this trap like a wild animal and finding a way to escape. Hasinger said.

In the near future, experts of Max Planck Institute will test a more stable option. At a branch of the institute in the city of Greifswald, the "Wendelstein 7-X" experimental reactor (worth over 400 million Euro) is under construction. It works based on a completely different structural principle.

A special feature of "Wendelstein 7-X" is that the magnetic trap is only formed by the external conductor coils, the plasma is securely held inside. Thanks to the world's most modern supercomputer, one can calculate the exact shape of these magnets. Each magnet weighs 6 tons, worth 1 million Euro and people use up to 70 such rolls. When joined together, they create a trap from giant.

The first 5 years of the experiment will begin. "If we succeed, this will change the world. Imagine that only 3 bottles of water will be able to provide electricity for the whole family for a year," Hasinger said.