Europe develops a new fuel source for JT-60SA

Building a fusion reactor requires mastering an extraordinary range of technologies. From plasma heating to diagnostics and cryogenics, the engineering challenges are many and demand deep know-how. Research has laid much of the groundwork, but it is industry that must turn the concepts into components at scale. Through its contribution to ITER or JT-60SA, Europe is closing strategic gaps. Fuel sources are a prime example.

The powerful fusion reaction runs on hydrogen isotopes, which need to be continuously replenished. In devices like JT-60SA and ITER, operators will use a Pellet Launching System (PLS) to refuel and control the plasma instabilities. The PLS consists of three parts: an extrusion system to produce frozen hydrogen pellets, a centrifuge accelerator propelling them to high speeds and a transfer system injecting them into the plasma.

In Europe, these technologies have been developed by laboratories like CIEMAT, CEA, HUN-REN or IPP. However, the industry's experience is so far limited, as F4E's Fuel Cycle Mapping report pointed out. In this context, Fusion for Energy (F4E) is engaging with companies to build Europe's supply chain and deliver new reactor-scale fuel sources.

JT-60SA, the world's largest active tokamak, presents a unique chance to do so. In its next upgrade phase (after the upcoming operations), Europe and Japan will add a PLS to the device. In 2023, F4E signed a contract with Sener to manufacture the centrifuge accelerator. The firm, an aerospace supplier, completed the component in under three years. The 5-metre-long centrifuge is now at the Max Planck Institute for Plasma Physics (IPP), where it will later be integrated and tested with other PLS parts.

"Our close collaboration with IPP was essential. We leveraged their expertise in previous generations of centrifuges to modernise the technology and deliver a system capable of very high performance," explains Nandor Hajnal, Technical Officer for F4E. The centrifuge is designed for rapid and precise fire: using a rotating arm, it can accelerate up to 80 pellets per second, at speeds of up to 600 metres per second.

"We're delighted to see the development of the pellet centrifuge accelerator come to fruition. Beyond its potential in fusion, this product also contributes to advancing key technologies relevant to other strategic markets, such as space, particularly for high-performance satellite momentum wheels," says Joan Manel Casalta, Head of Science Programmes at Sener.

In parallel, F4E has kicked off the procurement of the extrusion system for JT-60SA, offering a new opportunity to strengthen Europe's know-how in fusion fuel-cycle technologies.