Tokamak Energy — a leading global commercial fusion energy company based in the U.K. — and the University of Illinois have been awarded a $500,000 grant from the U.S. Department of Energy to collaborate on the development of liquid lithium systems for spherical tokamak devices (toroidal apparatus for producing controlled fusion reactions in hot plasma).

The Center for Plasma Material Interactions (CPMI) at the University of Illinois at Urbana Champaign is the premier university-based lithium technology laboratory in the U.S. CPMI is developing novel divertor concepts that utilize flowing liquid lithium as a solution to the erosion and impurity accumulation challenges faced by solid divertors.

Tokamak Energy

Lithium is very effective at pumping deuterium and tritium and has been shown to improve plasma performance. This new work will add a continuous plasma source and a lithium distillation column to the lithium loop at CPMI to demonstrate that the proposed technology is relevant for spherical tokamak fusion reactors.

The low-hydrogenic-recycling concept aims to achieve higher plasma confinement times, higher core-electron temperatures, a more stable plasma and enable a low-cost fusion reactor. Existing collaboration work between the two parties is seeking to create a reactor-compatible, flowing-lithium-divertor plate for testing in Tokamak Energy’s latest spherical tokamak, the ST40. In a world-first, the ST40 recently achieved a plasma temperature of 100 million° C, the threshold required for commercial fusion energy.

The new project also seeks to determine the amount of tritium that liquid lithium can pump and how quickly unburnt tritium can be recovered, which is essential for any lithium-based fusion concept. The outcomes are expected to inform a model of the fuel cycle within a tokamak fusion reactor.

Ultimately, this research hopes to fast-track the end of global reliance on fossil fuels by making fusion energy a globally available and secure energy resource. It is believed that spherical tokamak technology and high temperature superconductor magnets will enable world-wide access to clean, sustainable, and low-cost energy.