Tokamak Energy, a company working on nuclear fusion technology, has recently announced a major breakthrough in its research and development. Testing of its cryogenic power electronic technology for its superconducting magnet's high-efficiency operation was, by all accounts, a big success.
The company's bid to provide the world with near-limitless energy uses a combination of spherical tokamaks and high-temperature superconducting (HTS) magnets. According to reports, tests of the new power electronics showed twice the efficiency of previous systems.
“We have now invented a new type of cryogenic power supply, based on the latest power electronics devices, that is highly efficient at low temperatures. This means we have the potential to reduce cryogenic capital and running costs for HTS magnets, by 50%, or more. This novel approach will provide significant cost savings, contributing to the achievement of commercial fusion energy,” said Tokamak Energy CEO Chris Kelsall.
This resulted in a substantial reduction in the power required to cool the HTS magnets, lowering the cost of future fusion power plants. This is a critical step toward commercializing and scaling fusion technology.
The use of superconducting magnets in tokamak reactors, like the one under development by Tokamak Energy, is required to concentrate and isolate plasma so that it can reach the incredible temperatures needed for nuclear fusion. Cryogenic cooling is one of the numerous energy issues for such a system — hence the focus on making it as energy-efficient as possible. This new approach uses a higher-efficiency power converter within a vacuum cryostat.
Back in 2020, Tokamak Energy was awarded significant multi-year funding by the U.S. Energy Department to enable the company to further its research and collaborate with experts on U.S. soil.
The company's ST40 prototype reactor is being developed in collaboration with Oak Ridge National Laboratory and Princeton Plasma Physics Laboratory. The U.K. government awarded a research grant as part of the Advanced Modular Reactor initiative.
Tokamak fusion reactors are not a new idea and can trace their routes back as far as the 1960s. Back in 2005, one Russian T3 tokamak even managed to generate the temperatures needed for fusion, far ahead of others in its day.
However, older models required far more energy to achieve fusion than could be harvested from them — not ideal. To attempt to overcome this problem, Alan Sykes, a cofounder of Tokamak Energy, conducted research back in the 1980s and found that altering the geometry of exiting tokamak designs boosted performance significantly.
He also discovered that using better magnetic confinement using HTS magnet technology could, in theory, offer a path to make such reactors commercially viable.
HTS magnets are composed of rare earth copper barium oxide fashioned into thin strips of less than 0.1-mm thickness. Such magnets are able to produce far greater magnetic fields while taking up less area when shaped into coils — handy when space is at a premium.
To help achieve this, Tokamak Energy has been collaborating with the European Organization for Nuclear Research (CERN) to develop HTS magnets scalable to the size required for fusion power modules. For Tokamak's part, they are developing two core technologies, the main compact spherical tokamak and HTS magnets.
“These enabling technologies are essential to the development of economic fusion,” explains Kelsall.
In fact, according to the company, their fusion power system should be able to produce 500MW of heat or 150MW of electricity. This is enough to heat plasma within the reactor to temperatures of 100 million degrees Celsius (180 m deg. F), which is more than enough for commercial fusion energy.
“If so, Tokamak Energy will be the first commercial fusion developer to achieve this key milestone in a controlled plasma,” Kelsall said. “However, we also believe there are other key ingredients which are essential to achieve commercial fusion.”
Nuclear fusion is the "Holy Grail" of energy generation
Tokamak Energy's current ST40 reactor has, thus far, not been able to achieve temperatures of anything like this as of yet. However, it has managed to reach 15 million degrees Celsius (27 m deg. F) in its first year of operation. The breakthrough seen in the testing of its magnets should, the company claims, enable their ST40 reactor to overcome repulsive forces between deuterium and tritium ions, bringing them close enough to fuse.
If achieved, this would make it the first privately-funded fusion reactor to achieve temperatures required for nuclear fusion sustainably.
And this is critical for producing clean, low-cost, secure, and near-limitless energy in the future. It will also be incredibly safe and reliable.
“The race to commercialize fusion will gather further pace next year as fusion companies make further technology advances,” Kelsall predicts.
“Applications developed within the fusion sector will present substantial crossover opportunities in different industries, including aerospace, industry, and health care. 2022 will see the public and private sectors continue to work closely, to capitalize on the immense opportunities that fusion offers. This augurs well for the future,” he added.
Nuclear fusion should, once commercially viable, require less space to set up and with its inherent safety should make it possible to build fusion reactors closer to population and industrial centers. This means it will be cheaper and easier to deploy.
All a big plus in a world apparently on a mission to move for energy security. So far, things are looking very bright for companies like Tokamak Energy.