UK Engineers Achieve Fusion Milestone with 3D Magnetic Coils

Scientists at the UK Atomic Energy Authority (UKAEA) have made a significant breakthrough in fusion energy research by stabilizing plasma through a pioneering experiment. This achievement marks a critical step toward realizing the potential of limitless energy through nuclear fusion.

The researchers successfully implemented a new method using 3D magnetic coils to create a magnetic field around a spherical tokamak, specifically the MAST Upgrade, allowing for unprecedented plasma stabilization. This innovation addresses one of the major challenges in fusion energy—the difficulty of maintaining plasma stability during the fusion process.

Nuclear fusion, the same reaction that powers the sun, occurs when two atoms collide, forming a heavier nucleus and releasing vast amounts of energy. Tokamaks, which utilize strong magnetic fields, are designed to control the burning plasma necessary for these reactions.

Located at the Culham Centre for Fusion Energy in Oxfordshire, the MAST Upgrade began operations in 2020. It serves as the largest spherical tokamak currently in operation, and its design enables scientists to confine fusion fuel at extremely high temperatures, creating the plasma needed for fusion.

While this process is promising, it also comes with challenges. If the pressure, density, or current levels within the tokamak become too high, the plasma can destabilize, leading to inefficiencies and potential damage to expensive components within the facility.

In an official statement, the UKAEA team detailed their success in suppressing Edge Localised Modes (ELMs), which are instabilities that can occur at the plasma’s edge and pose significant risks to nuclear fusion infrastructure. The team utilized Resonant Magnetic Perturbation coils to apply a small 3D magnetic field, achieving complete suppression of ELMs for the first time in a spherical tokamak.

“Suppressing ELMs in a spherical tokamak is a landmark achievement,” stated James Harrison, Head of MAST Upgrade Science at UKAEA. “It is an important demonstration that advanced control techniques developed for conventional tokamaks can be successfully adapted to compact configurations to develop the scientific basis for future power plants like STEP,” he added, referring to the Spherical Tokamak for Energy Production initiative.

This experiment was conducted during the MAST Upgrade’s fourth scientific campaign, which focused on plasma characteristics and exhaust control. The findings from this project will directly inform the design of future ELM control systems for the STEP program, which aims to achieve net electricity generation from fusion by 2040.

The UK government has committed £2.5 billion to support nuclear fusion advancements, underscoring its importance as a potential solution for sustainable energy. The successful stabilization of plasma using innovative techniques positions the UK at the forefront of fusion research, bringing the world closer to harnessing this virtually limitless energy source.