Tokamak Energy Announces STX Advanced Prototype on Path to Demonstrate Grid Ready Fusion Power in the Early 2030s

  • STX will achieve a higher sustained triple product¹ than any previous device
  • ST-E1 fusion pilot plant will produce up to 200 MW of net electrical power

Tokamak Energy today announces plans for its advanced prototype, STX, formerly known as ST80-HTS, which will be the world’s first high field spherical tokamak using high temperature superconducting (HTS) magnets, at scale. STX will demonstrate multiple advanced technologies required for the delivery of commercial fusion energy. With build completion planned in 2026, it will also demonstrate the key operating advantages of the spherical tokamak and inform the design of the ST-E1 fusion pilot plant. This in turn will demonstrate the capability to deliver electricity into the grid in the early 2030s, producing up to 200 MW of net electrical power.

STX will achieve higher sustained triple product (nT𝝉E) than any previous fusion device, approaching the level required for commercial fusion energy. Triple product is a widely recognised fusion industry measure of plasma density, temperature and confinement, collectively a key measure of progress on the path to realising commercial fusion.

In addition, STX will push the boundaries of fusion conditions in a compact spherical tokamak, with long pulse (~15 minute) control of the plasma. While existing devices have shown that strong triple product results can be achieved for a second or less, typically performance quickly diminishes as pulse duration increases. STX will target the significantly longer pulse durations that are needed for sustained high power output in commercially competitive fusion power plants.

Earlier this year, the company’s ST40 spherical tokamak reached a world record-breaking 100M °C plasma temperature in a compact spherical tokamak – the threshold for commercial fusion energy. ST40 also achieved the highest triple product of any private fusion energy company.

Chris Kelsall, CEO of Tokamak Energy said: “At a time of heightened global concern with energy shortages and escalating prices, there is an acute need for new, clean, dispatchable technologies to reduce carbon emissions, provide grid flexibility and security of power supply.  Our roadmap for pioneering commercial fusion energy has the potential to deliver a game-changing solution. Our next high field spherical tokamak, the STX, has the goal of demonstrating the engineering solutions needed to make commercial fusion energy a reality, providing the foundation for the global deployment of fusion power plants in the mid-2030s.  This would provide humanity with access to clean, sustainable, on demand and low-cost energy, wherever and whenever it is needed.”



¹Triple product (nT𝝉E): Any device that is going to make fusion energy a commercial reality requires a plasma (an ionized gas of charged particles / hydrogen nuclei) with a high triple product. nT𝝉E is a widely recognised measure of progress towards the achievement of commercial fusion plasma conditions.  There are three plasma conditions that must be met simultaneously:

  1. Density, n – can the device contain a dense enough plasma so that a sufficient number of fusion collisions occur?
  2. Temperature, T – is the device capable of heating the plasma so that the charged particles move fast enough to fuse with each other, when they collide?
  3. Confinement time, tE – can the device keep the charged particles within the plasma for long enough to sustain fusion reactions?
1152 864 jacquireid