A new fusion experiment in the UK to address the plasma exhaust issue in fusion energy development has been given a £21m boost from EUROfusion and the Engineering and Physical Sciences Research Council.

The experiment dubbed as Mega Ampere Spherical Tokamak (MAST) Upgrade will be carried out at Culham in Mega Ampere Spherical Tokamak.

At the Culham Science Center, the UK Atomic Energy Authority is carrying out the assembly of MAST Upgrade and the device is expected to begin its operations within few months. 

The funding will be used for plasma exhaust enhancements which will be undertaken in various phases until 2022.

MAST Upgrade Operations Head Andrew Kirk said: “MAST Upgrade provides a uniquely flexible test bed for plasma exhaust physics in all divertor configurations. This extra funding will enhance our capabilities even further, enabling MAST Upgrade to assess alternative divertors for use in the first fusion power plants.”

According to the researchers, the biggest challenge faced by a future fusion power plant that uses the tokamak design comes from the controlled exhaust of power and particles from hot fusion plasma, via the divertor portion of the reactor.

Constant need to replace reactor components along with adverse affect in economics and electricity costs result from extreme power loadings in a conventional divertor, as per the researchers.

It is for this reason, divertor and exhaust physics have become an important part of the reactor design work of EUROfusion in its EU Roadmap to the Realisation of Fusion Energy.

To possibly solve the problem, the flexible divertor design of MAST Upgrade is already focussed on assessing a number of configurations. Included in them is the new Super X divertor which has been designed to bring down temperature of the particles by steering them on a longer exhaust way away from the plasma.


Image: MAST Upgrade under construction. Photo: courtesy of Crown.