ST40 World first to achieve 100 million degrees in a compact spherical tokamak

Tokamak Energy Announces Triple Product on the Path to Commercial Fusion Energy – Presented at the American Physical Society Plasma Physics Conference

Tokamak Energy today announces that its ST40 spherical tokamak has achieved a triple product¹ result of 6×1018 keV.s.m-3. This result was achieved earlier this year at a plasma temperature of 100 million degrees Celsius, the threshold required for commercial fusion energy, in a spherical tokamak with a plasma volume of less than one cubic meter; 15 times less volume than any other tokamak which has achieved this temperature.

The triple product achieved is the highest by a private fusion energy company.  Triple product¹ is a widely recognised fusion industry measure of plasma density, temperature and confinement, collectively a key measure of progress in the path to realising commercial fusion conditions.  The company has been invited to present the results today at the 64th Annual Meeting of the American Physical Society’s Division of Plasma Physics in Washington, USA.

Chris Kelsall, CEO of Tokamak Energy said: High performance in smaller spherical tokamaks is the key to commercial fusion power.  Our latest achievement further substantiates this optimal route to clean, secure, low cost, scalable and globally deployable commercial fusion energy.  We are proud to have achieved this result in collaboration with the Princeton and Oak Ridge National Laboratories.”

The ST40 spherical tokamak is now undergoing an upgrade and will further develop operational experience and efficient technologies for future devices which the company will be announcing soon.



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?
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