Case Study – Tokamak Energy

Tokamak Energy

The Company

A spin-out from the Culham Centre for Fusion Energy, Tokamak Energy is working on nuclear fusion, the long-awaited holy grail of the energy field. Fusion reactions power the sun and the stars and are extremely hard to replicate, but harness this stellar reaction and clean, green, safe and abundant energy could be a reality around the world. The promise is tantalising, and momentum is building, as evidenced by a recent blog from Beauhurst, highlighting the company’s continued success in attracting private investment during the COVID-19 pandemic, resulting in £123m raised to date, the second largest sum of any cleantech business in the UK. This was on top of the recent announcement that it had won an award of a further £10m grant from BEIS to advance work on its next generation device.

The Science

Tokamak Energy

Unlike fission, fusion energy does not pose the risk of meltdown or produce long-lasting radioactive waste but has extremely high energy density and the potential to provide inexhaustible fuel. By combining spherical tokamaks with superconducting magnets, Tokamak Energy is building a device that will mimic the sun’s process to generate a cheaper and more sustainable alternative energy source. The Company forecasts that by 2050 fusion energy could account for a fifth of total energy production and lead to a 20% reduction in CO2 emissions globally. Beyond renewable energy, Tokamak Energy’s technology also has potential uses in proton beam therapy, particle accelerators, scientific research and other industrial processes.

In 2017, Tokamak Energy unveiled its ST40 spherical tokamak. The device aims to be the first in the world to produce the plasma temperatures necessary for fusion. In 2018, the Company achieved a significant milestone as the ST40 reached 15m degrees. Its next challenge is to attain a temperature of 100m degrees, close to the level required for fusion. COVID-19 has presented challenges for the company, with key components for the upgrade being stranded on the wrong side of lockdowns around the world, but Tokamak is still aiming to achieve this critical milestone within the next 12 months.

Watch how Tokamak Energy is developing nuclear fusion

The Impact of UKI2S Investment

UKI2S was the founder investor in Tokamak Energy in 2010, making a very modest £25,000 pathfinder investment to support the founders in shaping their initial thinking as to how a fusion neutron device might be developed commercially. Since then the Fund has continued to invest further in several rounds of financing and has helped Tokamak Energy to find other private and public investment, including £1m from the Innovate UK UKI2S Accelerator. Over and above the funding, UKI2S has been a long term presence around the board table and has been instrumental in bringing in Non-Exec Directors, including the Chairman, as well as the current CEO.

The £10m award from BEIS forms part of the UK Government’s Advanced Modular Reactor project designed to advance next generation nuclear energy. This will fund design and prototyping work on the divertor (effectively the exhaust system) for the next generation device. The plasma temperatures in a fusion device are unimaginably high at around 150,000,000,000 degrees meaning that the temperature of the exhaust system, even across a supposedly perfect vacuum, has to be capable of withstanding heat loads equivalent to 100,000 midday suns. Just one of the engineering challenges the company is tackling in their quest to deliver some of the cleanest and cheapest energy that the world needs.


“We are excited by the opportunity to tackle the substantial engineering challenges in fusion and motivated by the global impact this technology will have.”

David Kingham, Deputy Executive Chairman

Find out more about Tokamak Energy visit the website