Nuclear fusion has long been hailed as a potential source of abundant, cheap, and carbon-free energy. After all, the process — which involves fusing hydrogen atoms together under tremendous pressure and incredibly high temperatures to release enormous amounts of energy — is what powers the sun and the stars. Despite decades of effort, researchers have yet to succeed in harnessing the power of fusion, much less commercializing the process. However, a Canadian company plans to begin construction later this year on a facility in the United Kingdom that is intended to serve as a proving ground of sorts for its proprietary fusion process whose only waste byproduct is helium.
Known as the Fusion Demonstration Plant, the approximately $400 million facility will showcase the magnetized target fusion technology developed by General Fusion. Formed in 2002, General Fusion has its headquarters in Burnaby, British Columbia, Canada, along with locations in Washington, D.C., and London.
In June, General Fusion and the U.K. Atomic Energy Authority — the U.K. government body responsible for researching and developing fusion energy — announced that the privately funded company would build and operate the FDP at the UKAEA’s Culham Science Centre, near Oxford, England . Construction is scheduled to begin in 2022, and operations are expected to start in 2025, according to a June 16 news release from General Fusion. Following completion of the facility, General Fusion will lease it from the UKAEA.
The MTF process
Efforts to conduct fusion typically seek to combine the hydrogen isotopes deuterium and tritium. Deuterium, which has one proton and one neutron in its nucleus, is available in seawater. Tritium, which contains one proton and two neutrons, can be extracted from lithium.
If heated to temperatures on the order of 150 million degrees Celsius, the isotopes will speed up to the point that they fuse when they collide. In doing so, deuterium and tritium combine to form helium, while also releasing a spare neutron. The fusion of the two isotopes creates a significant amount of energy, which then may be captured and converted to electricity.
General Fusion’s magnetized target fusion technology differs from other approaches to achieving fusion in that it does not rely on massive superconducting magnets or large lasers. Instead, the MTF device consists of three main components: a rotating chamber, a plasma injector, and a compression system.
The chamber is filled with liquid metal and rotated rapidly, forming a central cavity. Hydrogen plasma then is injected into this cavity. At the same time, the compression system surrounding the chamber uses high-pressure pneumatic pistons to compress the metal, increasing the pressure and temperature in the chamber to the point at which fusion can occur. The heat from the resulting release of energy is transferred to the liquid metal. This heat then is to be extracted from the metal and used to create steam, which in turn would power a turbine to create electricity.
Demonstrating the process
As a demonstration facility, the FDP will not generate electricity, says Jay Brister, the chief business development officer for General Fusion. “The role of the FDP is to prove the viability of our MTF technology so we can scale it to a commercial pilot plant,” Brister says. “To do this, we will create fusion conditions in a power-plant-relevant environment without producing power,” he explains. “The FDP will create neutrons, and the data it creates will provide the information we need to build a commercial pilot plant that generates electricity. Our goal is to bring zero-carbon fusion energy to the world by the early 2030s.”
“The facility is the result of over a decade of development,” Brister says. “It assembles proven components into a scaled version of our commercial machine.” At 70% of the scale of the planned commercial pilot plant, the approximately 11,000 sq m facility will house an estimated 3,000-ton MTF machine, Brister says.
The building design had to account for the fact that the machine and the science are advancing together.
“The facility must provide adequate space to install, commission, operate, service, repair, and modify the machine,” Brister says. “The design must also maximize the aesthetic effects and impacts of this disruptive technology for visitors, investors, (and) employees” while also helping attract world-class talent. “Finally, the design must also consider and provide space and flexibility for potential future expansions and modifications,” he says.
The visitor experience
In November 2020, General Fusion hired the U.K. architecture firm AL_A to design the demonstration facility. The architectural design includes a focus on the experience of visitors to the facility. “Architect Amanda Levete (the founder and principal of AL_A) has designed our facility to display the promise of fusion by integrating science with nature,” Brister says. “When we are able to accommodate visitors on the Culham campus, environmental designs will include educational corridors with informative displays that capture visitors’ imaginations as they contemplate a clean energy future.”
In January 2020, General Fusion entered into an industrial partnership with the global engineering and construction firm Hatch Ltd. Under the terms of the partnership, Hatch invested in the company and agreed to provide power plant engineering and related expertise in the development of the FDP.
Both parties benefit
Locating the FDP at the Culham site offers benefits for the UKAEA as well as General Fusion. “This new plant by General Fusion is a huge boost for our plans to develop a fusion industry in the U.K., and I’m thrilled that Culham will be home to such a cutting-edge and potentially transformative project,” said Amanda Solloway, a member of Parliament and the U.K. government’s minister for science, research, and innovation, in the June 16 news release. “Fusion energy has great potential as a source of limitless, low-carbon energy, and today’s announcement is a clear vote of confidence in the region and the U.K.’s status as a global science superpower.”
“Coming to Culham gives us the opportunity to benefit from UKAEA’s expertise,” said General Fusion CEO Christofer Mowry in the news release. “By locating at this campus, General Fusion expands our market presence beyond North America into Europe, broadening our global network of government, institutional, and industrial partners. This is incredibly exciting news for not only General Fusion but also the global effort to develop practical fusion energy.”