GUY PHILLIPS

Fusion for Energy’s head of unit for JT-60SA tells us more about the challenges of nuclear fusion and its future

HOW DID IT FEEL TO SEE THE FIRST JT60SA PLASMA?

It was an amazing moment for us. After 15 years of working on this machine, we signed an agreement with the Japanese in 2007, and in 2023 we actually started operating the machine for the first time. It’s a huge achievement and we’re really proud and happy to have got to that point.

WHAT HAVE BEEN THE BIGGEST CHALLENGES IN CONSTRUCTING JT-60SA AND IN DEVELOPING NUCLEAR FUSION ENERGY?

Probably the biggest thing is the materials for construction. It’s not well understood how different materials will react under the neutron loads that they will have in a device that would be manufactured for power production. Within Fusion for Energy, we have a group looking after a linear accelerator. This is being built so that we can study the material behaviours and we can better understand how the materials would behave without actually having a fusion device to study materials. At the moment it is in the prototyping stages, so there’s a lot of work that needs to be done on this before we get to the point of understanding more about the materials, but it’s a critical step.

HOW LONG WILL JT-60SA CONDUCT EXPERIMENTS AND HELP OTHER TOKAMAKS LIKE ITER?

I would say there’s not really a life span.

It’s something which we intend to develop over the years. At the moment we have operation plans well into the 2030s and into the future. The intention is that JT-60SA remains as a support device for ITER, so when things come up on ITER we should be there and ready to be able to react and adjust things accordingly, and experiment accordingly. There’s no intention to shut the device down and stop everything, so it’s indefinite at the moment.