All entries for Thursday 24 November 2022

SOFT32 – A Reality Check for what fusion power really is

A belated entry considering that SOFT32 took place way back in September (incidently just after we had reproduced decent Gen2 RSB samples)

This is the first in a somewhat belated set of entries but this blog aims to be unlike others and not just get abandoned because things are busy, since that is more or less a given.

The 32nd Symposium on Fusion Technology (SOFT32) in Dubrovnik, Croatia took place from the 18th-23rd of September. This was the first hybrid/live conference since before 2020 since SOFT31 was a virtual conference held online. This conference is not long after JET's record-breaking dueterium-tritium campaign, holding a fusing plasma for 5s and ITER director Dr Bigot's untimely death in May.

Certainly, while there is a lot that can be done online, nothing beats the immersion that happened when you are interacting informally with people as well as being in the talks and the posters. It has given us a greater appreciation for the international effort to get fusion working and on how far ITER and JET has come.

The biggest takeaway was that each fusion reactor is more than just a reactor. For a tokamak reactor, the plasma chamber is only 1 part of the reactor. The reactor also has to comprise of the following facilities:

Cryoplant: Cooling the magnetic coils (LTS/HTS and copper) and cooling the dueterium/tritium for the fuel plant

Fuel plant: Harvesting and handling tritium from the fuel blanket within the reactor prior to use as fuel. Making the fuel pellets and injecting them into the reactor to fuel the plasma.

Gyrotrons: Powerful microwave resonators to pre-heat and energise the plasma prior to initiating fusion.

Neutral beam injector: Linear accelerator to initiate fusing plasma reactions once the plasma is energised from the gyrotrons:

Monitoring and diagnostics: Monitoring the status of the plasma, vacuum, shielding, magnets and blanket.

Heat rejection: Removal of heat both for useful work and 'cool' heat from the magnets and cryoplant.

When the scale of setting up a tokamak is understood it becomes clear that the reason fusion power takes such a long time is that it is very difficult and it has taken a long time just to appreciate what needs to be done alone.

So from this we can see that ITER is a very important project, not just because it was the only international collaborative project initiated between the USSR and America in 1987 but that it has also carved out a path to industrialization for companies and universities working on fusion power. This has also stimulated research and development into related technologies and facilities that are critical to a wide range of applications inside and outside of fusion power.

What is for certain is that we are now in a situation where practical fusion power is no longer falling in the trope of '20 years away and always will be' but there will be plenty of challenges involved.

With respect to the cWC-RSB project it has also shown just how much qualification reactor candidate materials require. Not just the shielding but also materials that form the blankets, divertors, coolant networks, steels and plumbing adjacent to the inner shielding. This goes a long way to why W is still the main candidate shielding material since it has the most testing and data. The recent succesful JET campaign was used in part to qualify the W:Be inner wall, referred to as the ITER-like wall.

So the biggest conclusion we can take from SOFT32 alongside all the networking and knowledge about fusion is what is needed for a practical shielding material and the experimental data needed. W has blazed the trail so that cWC-RSB can follow.

Jessica Marshall : 24 Nov 2022 15:27 |  Tags: Fusion Power Iter Jet Soft32 |  Comments (0) |  Close comments |  Report a problem