Stellarator Fusion Reactor
>> What is a Stellarator
The Stellarator reactor is a way for humans to create safe, clean and renewable energy. This reactor is one of the technologies scientists believe could lead to real-world fusion. The name Stellarator comes from the probability of harnessing power from the stars and the sun.
A Stellarator confines plasma in a twisted doughnut shape similar to that of a Tokamak. To confine the plasma (yellow), magnets (blue) are placed around the reactor vessel at different angles depending on how that part of the vessel is twisted. Although the Strellarator bears a resemblance to the Tokamak, they are still different.
The first stellarator was created in 1950 under Princeton Plasma Physics Laboratory founder, Lyman Spitzer. The Stellarator he created is very stable with little risk of plasma disruptions.
>> How does it Work
A stellarator reactor functions in a very similar fashion to a Tokamak Reactor. It uses magnetic fields to confine plasma in the reaction chamber that is shaped like a twisted torus. These magnetic fields allow scientists to control the plasma particles and create the right conditions for fusion reactions to occur. Stellarators use extremely strong electromagnets to generate twisting magnetic fields that wrap the long way around the torus.
The stellarator uses less power than a tokamak to sustain the plasma. However, because of the twisted shape of the reactor vessel, it would also seem that it is very complex, especially the magnetic field coils. Because of this complex design, scientists are more invested in other models of fusion reactors rather than the stellarator.
>> Differences Between
Tokamaks and Stellarators
Stellarators have lots of advantages over Tokamaks, the other main technology that scientists are exploring for fusion power. Stellarators require less injected power to sustain the plasma, a Stellarator would have greater design flexibility and allow for easier aspects of plasma control. However, these benefits come at the cost of the Stellarator being very complex, especially for the magnetic field coils.
Spitzer and Mercier stated that there are three different ways to twist the magnetic field: 1 creating a poloidal field by a toroidal electric current; 2 rotating the poloidal cross-section of stretched flux surfaces around the torus; 3 making the magnetic axis non-planar.
While Tokamaks use the first approach, Stellarators usually rely on the other two methods, namely, in Tokamaks the twisting is produced by a toroidal plasma current and in Stellarators by external non-asymmetric coils.
>> Wendelstein 7-X
What Is It?
a large Stellarator with modular superconducting coils which enable steady state plasma operation in order to explore the reactor relevance of this concept.
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Where is it?
The location of the Wendelstein 7-X is at Greifswald Branch Institute of the IPP in Germany. Tho many components of the project were manufactured outside of Germany.
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What is the goal of the Wendelstein-7X?
Its objective is to investigate the suitability of this type for a power plant. It will test an optimized magnetic field for confining the plasma, which will be produced by a system of 50 non-planar and superconducting magnet coils, this being the technical core piece of the device.
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How much power will it generate?
Wendelstein 7-X will never generate a single watt-hour of energy. Rather it is intended to establish the potential of stellarators as power plants by demonstrating their main advantage over tokamak fusion reactors, which is the ability to operate continuously rather than only in short bursts.
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How much will it cost? Who is funding it?
more than €1 billion ($US 1.1 billion) and one million man-hours
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The people who funded this project are Greifswald's Technical Services along with the Integrated Technical Centre and the KIP Group at Garching. Firms throughout Europe that include: Karlsruhe Institute of Technology Jülich Research Centre Over 160 person-years of work was invested by specialists in superconductivity technology from the Polish Academy of Sciences Oak Ridge and Los Alamos
This is a picture inside the Wendelstein-7X reactor hall
This is a picture of the inside of the reactor vessel of the Wendelstein-7X. Here you can observe the twisted shape of the vessel and the special lead tiling that handles the high temperatures of plasma
>> Videos
Here are some shore videos about the Stellarator and the Wendelstein-7X
