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Q&A with General Fusion – Getting Down to Brass Tacks

Posted on December 25, 2022 by djysrv

                  Q&A with General Fusion – Getting Down to Brass Tacks

Editor’s Note: The phase “Get down to brass tacks” is an idiomatic expression, like a ‘dime a dozen,’ meaning – to start discussing or considering important details. For example, “We’ll get down to brass tacks and complete the research method tomorrow.” or,  “Don’t be intimidated by the lengthy resort. Just get down to brass tacks.”

Fusion energy is the process that powers the sun radiating its life giving energy across 93 million miles of space. On 12/01/22 in a blog post titled –  How Fast Will Fusion’s Promise Come True? – a list of ”get down to brass tacks type’ questions were published asking, without regard to any fusion energy developer, about the commercialization of fusion energy. The questions focus on the promises fusion startups in the U.S., Canada, and the UK are making to their investors and especially about efforts to master the technologies needed to achieve their project timelines for commercial plants.

In this blog post readers are provided with detailed answers to these questions from General Fusion, a leading developer of fusion technology, based in Vancouver, BC, Canada, about its drive to deploy commercial fusion powered electricity generation plants within the next decade. 

Background on Commercialization of Fusion Energy

Big Money Is Flowing into Commercialization of Fusion Energy

According to the 2022 report of the Fusion Industry Association (FIA), there are three dozen fusion energy startups which are attracting billions of dollars in investor commitments. It’s not just private investors who are pouring money into fusion. The Department of Energy for 2023 will be funded by Congress with a record levels of appropriations for fusion R&D and support for commercialization efforts.

Last October DOE announced a funding opportunity announcement (FOA) which is expected to award $5-25 million each to three-to-five project teams.  The principal applicant must be a for profit firm but partnerships with national laboratories and universities are acceptable. There are two “swim lanes” or tiers to the funding. The two tracks are;

  • Develop a pre-conceptual design / roadmaps for a pilot fusion plant

  • Come up with improvements to the performance of current fusion efforts none of which so far have produced a long duration self-sustaining fusion process.

Fusion developers are in a highly competitive race to develop unique, first-of-a-kind fusion power plants. The cost of their efforts have required, and will continue to require, hundreds or even billions of dollars from their investors as well as government financial support. No fusion developer wants either of these stakeholders to be put off by unanswered questions about the challenges they face.

Plus, there is growing confidence among commercial fusion developers who claim that their power plants are likely to be built in the 2030s. Yet, the director of the National Ignition Facility at Lawrence Livermore National Laboratory (LLNL) thinks this timeline isn’t realistic.

The scientists at LLNL are quick to clarify their recent accomplishment in the realm of fusion ignition has great scientific merit, but they also add a note of caution that the engineering work ahead to design and build commercial plants faces many uncertainties.

In response,  the current cadre of developers of commercial fusion plants say it is time to retire the old assessment that fusion is still 50 years in the future. Plus, MIT Technology Review, in its assessment of the LLNL accomplishment, noted, “While [laser driven] inertial confinement is the first fusion scheme to produce net energy gain, it’s not the most likely path forward for any possible commercial fusion efforts.”

Key Technical Challenges Facing Fusion Developers

Key technical challenges facing fusion developers fall in three broad categories that have to be resolved in order to build fusion energy plants for commercial use.  

  • Produce and maintain a long lasting, self-heating burning plasma by any of a variety of means

  • Develop materials that can withstand neutron bombardment over the plant’s lifetime, e.g., 40-60 years or longer; or work around that problem with alternative means of generating the plasma

  • Transfer the plasma heat out of the fusion space to generate electricity or for industrial process heat

Key Enabling Technologies Needed to Achieve Success

A lot of progress has been made in several key areas. According to DOE’s ARPA-E Program, more work needs to be done to address many technical challenges.

  • Advances in 3D printing that make for quicker and cheaper components

  • Development of super conducting magnets to control the plasma, but not all tokamaks use magnets and some fusion methods don’t use them at all

  • Applications in supercomputing to calculate best methods and engineering designs for creating and sustaining the plasma

  • Fabricating advanced materials need for the construction of fusion machines

  • Designing new control room instruments and operator interfaces needed for fusion machines

A Q&A with General Fusion

General Fusion is one of the leading developers globally working to achieve a commercial implementation of fusion energy. The Canadian company’s technology focus to develop a fusion power device is based on magnetized target fusion (MTF).

The firm was founded in 2002 by Dr. Michel Laberge.  General Fusion’s CEO is Greg Twinney, who was appointed last July. Previously, he was General Fusion’s Chief Financial Officer, In 2021 he led the company to achieve a successful oversubscribed $65 million Series E financing round. According to Crunchbase,the firm has raised $322 million from 32 publicly disclosed investors in 15 rounds of financing. 

General Fusion of Canada, in partnership with the UK’s Atomic Energy Authority (UKAEA), is on track to build a fusion demonstration project (FDP) at a site in Culham, England, 60 miles (100 km) west of London, as a precursor to a commercially viable pilot plant. Readers are referred to an online walk through of the stages of the firm’s magnetized target fusion process. General Fusion – Visual Capitalist Infographic


Questions Asked and General Fusion’s Answers

These questions were prepared by the NeutronBytes blog and emailed to General Fusion for a response. The published answers from the firm were not edited for content. A few minor changes were made in the format of the text to enhance ease of reading the material. Reference links were added to the text to clarify some technical aspects of the content. 

How close is GF to demonstrating core temperatures and pressure conditions for the fusion energy produced to exceed the heating energy injected into the reactions. Will you be able to do it once the Fusion Demonstration Project (FDP) is built in the UK?

After 20 years of research, technology advancements and large-scale test beds, General Fusion has proven its core technologies, which include its plasma injector and compression system. Now, we’re integrating that technology at power-plant-relevant scale in our fusion demonstration.

It will reach fusion conditions, including reaching our target temperature (10keV+) or 100 million degrees Celsius, while demonstrating the advantages of Magnetized Target Fusion (MTF) and refining both the optimal size and economics of a commercial fusion power plant. With these results, we will use established scaling laws to complete the design of our commercial pilot plant that will achieve net energy and put power on the grid.

You’ve committed to an ambitious set of milestones with plans to break ground in the UK next year (2023) and to have an operating facility by 2027. Are these plans realistic given the first-of-a-kind technology that you committed to for your design?

We’ve already proven our core technologies with large test beds and prototypes in our labs. The performance of these large-scale prototypes, combined with advanced modelling and simulation, give us confidence in the expected performance of our fusion demonstration and our timeline, which includes commissioning the integrated fusion machine by the end of 2026 and achieving expected performance in 2027.

Then, because our approach to fusion inherently addresses the major barriers to commercializing fusion through our mechanical compression system and liquid metal wall, we’re well-positioned to put a first commercial fusion plant on the grid in the early 2030s.

Unlike other planned fusion demonstrations, General Fusion uses an approach to fusion that translates to a commercial plant without requiring additional scientific or materials breakthroughs. When we reach net gain, it won’t be in a stand-alone lab experiment, it will be in a commercial power plant with a fusion machine scaled up from our FDP which is a scale-up from 70% to full scale.

In addition, our fusion machine will integrate with a traditional balance of plant; the fusion reaction heats our proprietary liquid metal which then runs to a heat exchanger to produce steam and drive a turbine generator. This is consistent with the balance of plant in a coal-fired power plant.

Why did you choose a combination of magnetized target fusion and inertial confinement fusion? What technological and economic benefits accrue from this design approach compared to Tokamak and Stellarator designs?

When Dr. Michel Laberge founded General Fusion in 2002, his sole purpose was to create affordable electricity from fusion power. To do this, he sought a practical approach – Magnetized Target Fusion (MTF) using mechanical compression. It’s the fusion equivalent of a diesel engine: practical, durable and cost effective.

This approach was originally conceptualized by the U.S. Navy in the 1970’s in response to the practical challenges associated with tokamaks, which had been under development since the 1950s. Dr. Laberge set out to apply modern enabling technologies such as supercomputing, 3-D printing and digital controls to this elegant approach to fusion.

The game-changer is our proprietary liquid metal wall in the fusion vessel that is mechanically compressed by high-precision steam-driven pistons, compressing a plasma to fusion conditions using a pulsed approach. This approach means we do not have to sustain a plasma indefinitely, but only long enough to be compressed, which eliminates the need for active magnetic stabilization, auxiliary heating or conventional divertors, all of which drive complexity, inefficiency, and cost in other approaches.


Plasma Injector: General Fusion’s plasma injector exceeds requirements with 10-millisecond self-sustaining energy confinement time without requiring active magnetic stabilization, auxiliary heating, or a conventional divertor.  Image: General Fusion file

The liquid metal wall protects our fusion vessel from neutron degradation, making our machine durable; breeds sufficient tritium for sustained plant operations; and provides a simple way to extract heat from the fusion reaction, by passing the liquid metal through a heat exchanger. These are challenges that other approaches to fusion have yet to solve.

Finally, our design does not require large superconducting magnets like magnetic confinement, or high-powered lasers or expensive targets, like inertial confinement, making our approach competitive with coal-fired power generation on an LCOE basis.

Editor’s Note: LCOE refers to “levelized cost of electricity” which is a measure of lifetime cost of an energy producing facility relative to the amount of energy it produces. See this Department of Energy slide show for briefing on how LCOE is calculated and used by investors to compare options.

Have you confirmed or do you have a target date for confirming the required performance parameters of the injector system?

On December 19, 2022, General Fusion announced core technology advancements: plasmas with self-sustaining energy confinement times of 10-milliseconds, and the validation of five-millisecond compression time for the FDP. Together, these indicate that our plasmas will last long enough to be compressed to fusion conditions, and that we’re on track to meet the FDP’s goal of achieving 100 million degrees Celsius.

Now, we are putting all these proven technologies together with our fusion demonstration program in the U.K. Basically, to successfully create commercial fusion with MTF, we need three things: (1) good plasmas, (2) good compression, and a (3) stable fusion process. We’ve demonstrated each of these in our test beds. Through the years, we have honed our technology and proven the core components with test beds.

  • When it comes to plasma – we’re leaders. We operate the world’s largest and most powerful operational fusion plasma injector. Over the years, we have created more than 200,000 plasmas. When it comes to our MTF approach, a “good plasma” means a plasma that holds its energy long enough (i.e. energy confinement time) to be compressed without any active magnetic stabilization, auxiliary heating or conventional divertors. Our most recent plasma injector has achieved the plasma conditions and energy confinement time required for compression in our fusion demonstration.

  • “Good compression” means the smooth, rapid and symmetric compression of a cylindrical liquid wall to a spherical shape in order to surround and compress a plasma to fusion conditions. Our latest compression technology test bed has achieved the smooth, rapid and symmetric compression required for our design.

  • Finally, through a series of tests, we have shown that neutron yield and temperatures increase when plasma is compressed, and we have also confirmed plasma performance when interacting with liquid metal.

What happens if one of the drivers doesn’t perform on time or not at all?

Our compression system approach is being designed to be robust and reliable in a power plant environment, with multiple layers of protection to ensure its operations.

  • First, digital control interlocks and real-time digital driver optimization means that operations will continue if a single driver were to fail within a cluster.

  • Second, the design will ensure that multiple mechanical driver failures within a cluster is highly unlikely.

  • Finally, the system includes several lines of defense against digital control failure. In short, if one driver fails, the machine will continue to operate, and the driver will be replaced at the next regularly scheduled maintenance.

For the FDP what are the key economic measures you will evaluate? The planned commercial plant is reported to be composed of two fusion machines to produce 230 MWe. That’s the approximate electrical generation capacity of a medium size PWR type small modular reactor (SMR). At 4,500/Kw such an SMR would cost $1.035 billion. Can GF produce two machines (in volume) combined to be competitive with that cost figure?

When General Fusion was founded by Dr. Michel Laberge, he set out to create a power plant that would be cost-competitive with other forms of energy, including coal and SMRs. Our innovative technology, such as the liquid metal wall, allows us to avoid damage to the fusion machine. It enables us to breed our own fuel. As a result, our two-machine commercial plant design will have total capital costs that are competitive with the SMR numbers cited above.

While capital costs are one dimension, levelized cost of electricity (LCOE) is what utilities use to evaluate their economics. Our estimated LCOE for nth-of-a-kind plants is competitive with coal and less expensive than fission SMRS due to the lower regulatory burden, operational costs, and fuel costs.

We improve the economics of fusion through our practical approach. General Fusion addresses the four long-standing barriers to fusion in more cost-effective ways than other fusion approaches.

  • First, we avoid the “first wall” neutron degradation challenge and ensure the durability of the machine with our proprietary liquid metal wall. The collapsing liquid metal wall, used to compress and heat magnetized plasma, uniquely shields the fusion machine from damage caused by high-energy neutrons released by the fusion reaction. With a machine that lasts longer, the economics improve.

  • We address fuel production challenges. Science Magazine recently reported that tritium costs upwards of $30,000/gram, questioning how fusion companies could rely on this as a fuel source. General Fusion is advantaged for using tritium as fuel because our approach produces its own fuel over the life the machine. In General Fusion’s MTF machine, tritium is produced with a breeding ratio high enough to sustain the operation of the plant over its lifetime. The liquid metal wall that surrounds and compresses our plasma to produce a fusion reaction contains lithium, which is converted into tritium by fusion neutrons. This reduces fuel costs to almost zero.

  • Getting heat out of a fusion machine has been a design challenge for many companies. We solve this with General Fusion’s liquid metal wall which provides a simple way to extract heat from the fusion reaction. In a commercial fusion power plant, the hot (500 degrees Celsius) liquid metal, which has absorbed heat from the fusion reaction, will be circulated from the fusion machine through a heat exchanger to produce steam that will drive a turbine and generate electricity. This is a fully industrialized process used in most modern power plants today that can be readily applied to our MTF approach to fusion. Using commercial off-the-shelf  steam systems provides another economic competitive advantage for General Fusion.

  • Finally, our MTF approach is cost-effective because it does not require powerful lasers, expensive targets or large superconducting magnets necessary to create or sustain the fusion process in other technologies.

What regulatory challenges do you expect to face in the UK, in the US? What is the current state of quality and safety standards for fusion machines, as compared to more stringent prescriptive regulatory requirements? Help or hinderance?

Regulatory bodies around the world recognize the potential for fusion energy and are developing regulations appropriate to the technology. For example, the UK’s Regulatory Horizons Council established a bold, forward-looking vision supporting the appointment of the Health and Safety Executive and Environment Agency to regulate fusion energy, rather than the traditional nuclear power regulator, the Office of Nuclear Regulation. The regulatory framework governing the permitting of fusion power plants is intended to be based on technology-appropriate requirements for fusion rather than a fission-based framework.

In the US, the Nuclear Regulatory Commission will regulate fusion power plants. The Fusion Industry Association is working with the NRC to establish a regulatory framework for fusion based on existing regulations for nuclear medicine in hospitals and research particle accelerators.

In Canada, the Canadian Nuclear Safety Commission is in the process of recommending new guidelines for the regulation of fusion energy that reflect the inherent safety attributes of the technology.

What are you doing to develop a global supply chain and how will your suppliers qualify to use fusion specific standards like fission’s NQA-1 for production of components for your machine?

We are developing relationships with suppliers and experts globally as we progress our commercialization strategy. From the beginning, General Fusion has been committed to using widely available materials, components and machining processes and standards, with our focus on commercialization.

In addition, through our relationship with UKAEA for our fusion demonstration, we are able to access the fusion supply chain which has supported the Joint European Torus (JET) on UKAEA’s Culham campus for the last 40 years. For example, we recently shared photos of the trial ring forged by Sheffield Forgemasters for our fusion demonstration. UK’s Sheffield Forgemasters brings to this project over 200 years of expertise creating complex steel components.

General Fusion’s UK team has set-up the pre-qualification questionnaire for use with the supply chain for its Fusion Demonstration Plant in Culham using existing standards for the nuclear industry which are largely technology-neutral. They focus on the entire manufacturing and planning process. With the UK using IRR17, and the US and Canada indicating respectively 10CFR Part 30 and Class II regulations, we are starting with an ideal trio: all technology-neutral and addressing the fundamentals of radiation protection.

In the US, fission nuclear facility applications have NQA-1 programs addressing quality assurance requirements for the whole life cycle (from design to decommissioning including waste and spent fuel management), which are specific to these types of technologies. This standard acts as a guide to meet the regulatory requirements for these technologies as prescribed by 10CFR Part 50 (production and utilization facilities), Part 71 (packaging and transportation of radioactive materials) and Part-71 (storage of spent nuclear fuel and high-level radioactive waste) and are not meant for fusion technologies due to drastic differences in radiological profile and risks.

We expect that the regulatory requirements for fusion energy will be created to appropriately address fusion energy technology. Due to the low radiological risks associated with this technology, the framework would be more in line with what is required of medical research or particle accelerators. Therefore, we anticipate that current nuclear suppliers will be able to meet the requirements easily, and other suppliers will be able to gain certification easily.

What are you doing to develop a workforce to build and later operate a GF fusion plant?

Our headcount has increased by about 30 percent in the last year, and we continue to grow. We are actively recruiting from both industry and universities to build out talent and recruiting from other fields as well.

In Canada, we are moving into expanded headquarters and lab space in Vancouver, BC, near the airport. Much of our intellectual property and talent originated in British Columbia and continues to do so. We also have a team in the US near Oak Ridge, TN, where we can draw on the existing research experts and the supercomputing capabilities located at the Oak Ridge National Laboratory.

Finally, our demonstration at Culham ensures we have access to a deep pool of talent and supply chain. Since JET will cease operations and start decommissioning in 2023, we are collaborating with the UKAEA to leverage the fusion talent base and supply chain there. As we think ahead to operating our fusion demonstration in the UK, we are building a team in the UK to ultimately commission and operate the demonstration facility.

While General Fusion does not plan to own or operate commercial General Fusion plants, we have developed a Market Development Advisory Committee (MDAC) with several potential utility and industrial early adopters. Our engagement with our MDAC will help us develop and support workforce needs to operate commercial plants, among other things.

Do you have any expressions of interest from utilities for a fusion plant? What are utilities telling you about their interests – e.g., risks, financing, licensing, operations?

General Fusion has set up a Market Development Advisory Committee – the MDAC, to cultivate interest in fusion plants by potential users. The committee is made up of utilities serving millions of customers, innovative renewable energy providers, and companies leading the decarbonization of heavy industry.


With their insight, we are building a portfolio of prospective, early adopters for fusion who will ensure that the performance and specifications of our commercial power plant will align with customer needs. Earlier this year, we signed an agreement with Bruce Power in Ontario to work together on a strategy to deploy Canada’s first fusion power plant. In general, our MDAC members are interested in developing economical, carbon-free baseload power generation with a manageable regulatory framework, and they recognize the advantages of fusion power in this context.

We announced that Bruce Power, General Fusion, and the Nuclear Innovation Institute (NII) entered a Memorandum of Understanding (MOU) to collaborate on accelerating the delivery of clean fusion power in Canada. Together, these organizations will evaluate potential deployment of a fusion power plant in Ontario, including in the tri-county Clean Energy Frontier region of Bruce, Grey and Huron.

Editor’s Note: Subsequent to the submission of these questions to General Fusion, on November 10, 2022, the firm announced that the Canadian Nuclear Laboratories (CNL) and General Fusion signed an MOU to pursue a series of joint projects to accelerate the deployment of commercial fusion power in Canada. The MOU will act as a framework for both companies to partner to advance fusion energy research and commercialization.

CNL and General Fusion will collaborate on projects in key areas, including feasibility studies, regulatory framework, power plant siting and deployment, infrastructure design, and testing and operations support. Overall, the aim is to develop fusion energy research capabilities within CNL, to support the goal of constructing a potential General Fusion commercial power plant in Canada before 2030.

What is the service life in years of a GF fusion machine?

Our current models estimate a life of 40 years; we expect there will be the potential to extend a plant’s life beyond 40 years with refurbishment of certain components.

At the end of life for a GF fusion machine how will it be decommissioned?

We expect the decommissioning of a General Fusion machine to be significantly less costly or complicated compared to nuclear fission plants because the radiation profile of our fusion fuel is similar to that of medical isotopes and our fusion machine will not generate any long-lived radioactive waste.

We also expect our decommissioning to be more straightforward compared to large historical fusion projects or some of our competitors’ designs. That is because our required tritium inventory is relatively low, and our proprietary liquid metal wall protects the fusion vessel from activation. As we finalize our commercial power plant design with input from our fusion demonstration, we will be able to refine our decommissioning plans and economics.

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