"Net zero": The strategy of the UK government on the way to thermonuclear energy
Material posted: Publication date: 07-12-2021
Natural gas prices in Europe have skyrocketed in recent months amid the transition to renewable energy sources and a reduction in supplies from Norway, Russia and LNG (liquefied natural gas) from the United States, as well as higher demand for electricity. In early August, gas futures in Europe were trading around $ 515 per thousand cubic meters, by the end of September they had more than doubled, in early October exceeding a record $ 1,900 per thousand cubic meters (at the peak, on October 6, to $ 1,937 per thousand cubic meters), with an average price in previous years of $ 200.

The energy crisis requires clear political solutions. And the question is acute: how to promote the transition to low-carbon energy under the "Net Zero" program in such conditions?

Thermonuclear fusion is a process that occurs in the cores of stars. It is a source of light and heat emitted by the Sun. For decades, scientists and engineers around the world have been

  • Fuel abundance: The fuel used in fusion reactions is practically inexhaustible. Deuterium is easily obtained from seawater, and tritium is produced using lithium.
  • Baseload Power: Fusion energy is independent of external factors such as wind or sun, making it continuously deployable if necessary.
  • High fuel efficiency: Fusion produces more energy per gram of fuel than any other process that can be achieved on Earth.
  • Carbon-free production: the product of the fusion process is helium.
  • No chain reaction: Synthesis is not based on a chain reaction; special heat conditions and pressure must be maintained continuously for synthesis to occur. Therefore, if there are technical problems, the fusion plant will be shut down immediately, and the process will stop within a few seconds or less.
  • Short-lived waste: thermonuclear power plants are not expected to produce long-lived waste.

The theory that thermonuclear fusion is a process that drives the Sun was first proposed in the 1920s, and the first laboratory demonstration of thermonuclear fusion was provided ten years later. During the experiment, helium was obtained from the synthesis of deuterium. Decades of attempts to use the energy released by the fusion of nuclei of light elements are explained by two advantages of this source: easily accessible and cheap fuel - hydrogen - and a significant energy yield. But it is very difficult to create the necessary conditions for the start of synthesis. In order for two atomic nuclei to merge into one heavier one, they must come together at a sufficient distance. This is prevented by electric repulsion, because the nuclei have the same (positive) electric charge. As a result, synthesis occurs in a very highly heated substance, where the thermal energy of the particles is large enough to overcome this repulsion. Therefore, specialists in thermonuclear fusion have to deal with heated plasma, which constantly tends to expand and cool down. The plasma cloud is held by powerful magnets.

After seven years of reconstruction, the MAST (Mega Ampere Spherical Tokamak) fusion reactor, located at the Culham Centre for Fusion Energy, began operating again in the UK. Now it is called MAST-Upgrade.

One of the most notable features of MAST Upgrade is the Super-X divertor. A divertor is a part of a tokamak that is designed to remove excess heat and impurities from the plasma. When existing divertor designs are scaled to future power plants, it turns out that these devices will experience very high thermal loads and they will need to be replaced every few years. The Super-X divertor should reduce thermal loads by about ten times, which will help solve one of the main problems of commercially viable thermonuclear energy. Inside the tokamak, the plasma reaches a temperature of 100 million degrees. Without a cooling system capable of coping with such temperatures, the materials in the structure would have to be replaced regularly, which would affect the operating time of the power plant.

Tasks and interim results

Physicists are studying two classes of systems for holding hot plasma: systems that operate almost continuously and use magnetic fields (fusion with magnetic confinement); and those that operate with short pulses, using the inertia of hot fuel to hold it in place for a short time (fusion with inertial confinement).

In addition to JET support and ITER training, the EUROfusion Consortium is designing a demonstration thermonuclear power plant called DEMO (DEMOnstration Power Plant) based on ITER. The UK provides many leadership roles and is one of the largest participants in the DEMO program.

The STEP program complements the work of private companies in the UK by acting
as a magnet for global investments. STEP will not be located in Calam, where JET is located. The final location of STEP has not yet been officially announced.

The UK Atomic Energy Authority (UKAEA) conducts The Oxfordshire Advanced Training Program (OAS). Since 2019, OAS has been training up to 350 technical trainees per year, specializing in areas such as energy, artificial intelligence, robotics and nuclear engineering.

Source: "Net Zero": The strategy of the UK government on the way to thermonuclear energy / Habr (habr.com ) 

Tags: assessment , UK , technology