A glimpse into the future for commercial fusion reactors
Most of the USD 7 billion in investment in private fusion initiatives has gone to companies that are building devices from the ground up. But recently, another breed of entrepreneur has come onto the scene: industrial players that offer some of the building blocks.
The challenge for the companies laying the groundwork for what will eventually become a supply chain for commercial reactors is that it is still a very early market. As long as the industry remains in an experimental phase, startups that develop supporting technology and services have to look for commonality among the different approaches and bet their business on the small number of technologies that will prevail.
Several of these supply chain innovators visited ITER for the Private Sector Fusion Workshop in May 2024.
Chang Ho Choi, Chief Technology Officer of EnableFusion, told the audience that his company aims to export technological experience gained on the Korean tokamak KSTAR, which achieved its first plasma in June 2008. Since then, KSTAR has been operating continuously with no major pauses—a successful demonstration of the engineering and project management practiced by national and international partners in the Korean ecosystem, according to Choi.
As a private-public partnership supported by the Korea Institute of Fusion Energy, universities, and private investors, EnableFusion, where Choi works with former ITER Deputy Director-General Gyung-Su Lee, targets as potential clients all fusion startups in the world that don't have the manufacturing capacity to build a reactor themselves. "We want to apply not only conventional design and manufacturing methods, but also digital twins and virtual simulators that use empirical data to allow scientists and engineers to explore new architectures with minimal trial and error."
Another company representing supply chain innovators at the ITER workshop was Kyoto Fusioneering, which has a three-phase approach to the fusion supply chain. First, they seek to establish partnerships with the academic community to gain early access to new ideas. "Once we see something that works, we make it into a reliable industrial component," said Christian Day, Senior Vice President and head of fuel cycle for the company. "That's our second stage. But knowing a component works is not sufficient; for that, integration testing is needed. Our third phase is designed to show a technology works in a given environment."
The company operates a platform for integration testing, called UNITY-1, at their research centre in Kyoto. They are also planning a second integration centre, UNITY-2, which will be built and operated through a joint partnership with Canadian Nuclear Laboratories (CNL) and will concentrate on fuel cycle systems. UNITY-2 will run at Chalk River in Canada, where a tritium facility is already available to store tritium by-products from the Canadian CANDU reactor fleet. Kyoto Fusioneering has three particular areas of technical expertise: plasma heating with gyrotrons, thermal cycle systems, and fuel cycle systems. "We want to act as enablers providing technology from these three areas to anybody who wants to build a power plant," said Day.
ExoFusion, a third company sharing its story at ITER, is a spinoff from the University of Texas at Austin, whose founders developed some of the first simulation-based transport models used to predict plasma profiles. "We've been actively involved in the development of groundbreaking gyrokinetic codes, including GS2 and GENE," said David Hatch, co-founder and Chief Technology Officer.
The company views simulation design using AI and machine learning as a low capital, high intellectual property business with the potential for big returns on investment. "Even though most of the fusion occurs in the core of the plasma, the core is very sensitive to what happens on the scrape off layer, which could be as small as a few centimetres wide in a plasma on the scale of metres," said Hatch. "Our focus is on the edge of the plasma, and this has resulted in a growing portfolio of innovations, including a new divertor concept."
Hatch's colleagues, Mike Kotschenreuther and Swadesh Mahajan invented the Super X divertor, which was among the first innovations in advanced divertors. This prompted a major upgrade of the UK-based MAST project, where the SuperX divertor was experimentally verified in 2021.
ExoFusion also has innovations in liquid metal alloys that are much more conducive to fusion performance than other alloys, in core edge integration for both tokamaks and stellarators, and in transport barrier initiation, control, and optimization. "Our business model is licensing and intellectual property," said Hatch. "We bring many of our own innovations to the table, but also consult. We're happy to take your concept and work with you to maximize its performance."
As public and private initiatives continue to experiment with different ways of harnessing the power of nuclear fusion, an industry is starting to take shape. A few entrepreneurs are making a business out of supplying the current generation of experiments—and those who pick the right approach to nuclear fusion will be very well positioned for what is likely to become a big industry.