BUILDING A REGULATORY FRAMEWORK | FUSION


its member companies say that all foreseeable fusion machines are particle accelerators – which is in agreement with the Commission position – and they want to ensure the regulatory definition “clearly reflects that technical understanding”. The latest proposed rule from the NRC staff makes clear


that particle accelerators can include fusion machines, but does not specify that all fusion machines are particle accelerators. The NRC proposed removing a statement that the definition applied “at energies usually in excess of 1 MeV.” FIA says the change is not needed to accommodate fusion machines and if it is removed it may expand the definition inadvertently to other technologies. The NRC staff have also updated the proposed definition of “fusion system” but FIA wants to retain a definition already in legislation (H.R. 6544, the “Atomic Energy Advancement Act”), saying it is simple, practical and robust and it avoids unnecessary inclusion of ancillary materials and systems that may be located on site but not part of the fusion machine. Other issues raised by FIA are largely around the draft


guidance (Preliminary Draft Guidance, NUREG-1556 Volume 22). The organisation says that it should apply solely to the use and possession of byproduct material in commercial fusion machines, not R&D. FIA says NRC staff have put “strong effort” into making


the preliminary draft guidance technology-inclusive and performance-based, particularly given the diversity of fusion technologies. But FIA saw instances where enhanced focus was given to deuterium–tritium (D-T) fusion-based systems and prescriptive requirements were mentioned For example one section states that tritium “will be


produced as a byproduct” and therefore tritium monitoring of atmospheric stacks is required. FIA wants a change to say tritium “may be produced.” Licence applications would currently have to include


statements about operating and emergency procedures for tritium handling systems and breeding blankets, but not all fusion machines will use these. Heat exchange systems currently “should be fully enclosed to prevent activated materials and tritium from becoming airborne” but FIA wants to replace this prescriptive language to allow a license applicant to state how they will ensure activated tritium does not become airborne. Separately one company, TAE Technologies, illustrated


the variety of fusion technologies now under development. In a May response it reminded NRC of the latter’s stated aim of a “risk -informed, technology neutral approach”. TAE Technologies offers a proton-boron fusion option, which it says has lower radiological and environmental risk. It said regulatory language and guidance should revise references to tritium to clarify that requirements do not apply in systems that do not use or produce tritium because otherwise uncertainty could mean the up-front investment needed to develop new options could be put at risk and create “a perverse market disincentive” against options that it said present lower risk. The FIA also wants applicants to be able to make the


commercial decision to begin construction at their own risk, and says commencement of construction prior to licensing should not serve as a basis for denial of the application. It says regulations should not impose a nine-month submittal timeline as a de facto requirement (as in 10 CFR 30.32). The


FIA also says a fusion machine may transition from an R&D focus to commercial operations without significant changes to the facility or design. There are a diversity of proposed fusion designs and “it seems incongruent to assume that a fusion machine transitioning from an R&D purpose to a commercial purpose, would significantly alter its impact on the quality of the environment such that adding a nine-month delay to its licensing review process would be justified”. In any case, it says, there is a government-wide effort


to reduce permitting timeframes for clean energy facilities and “this proposal to add in a nine-month delay, with no immediately obvious environmental or safety benefit, seems to run counter to this”. Some points refer to operating regimes such as


conducting a biennial physical inventory of all licensed material. This “could entail an extensive, physically intensive process that may require full shutdown of the facility for several days, potentially weeks” and with potential radiation exposure.” FIA says “there does not appear to be a clear safety basis” for this requirement. Some other requirements it says “are not relevant for


safety”: ● Appendix F requires construction monitoring and


acceptance testing to be done for power supplies and magnets, but these systems do not play any role in confining byproduct material from a public health and safety standpoint, only a fusion performance standpoint.


● Section 8.9.9 requires backup power supplies but many fusion machines will not need backup power supplies to maintain radiological safety.


● Much of the tritium guidance does not reflect the practical experience gained from existing fusion facilities like JET. For example, it should not be assumed a priori that fire detection systems need to shut down ventilation systems to minimise the risk of tritium oxidation


Looking to the mass market One potential fusion operator, Helion, has asked the NRC not to delay in moving to a licensing framework for a commercial fusion industry where multiple reactors are produced in series and to ensure that its environmental regulations are in scale with the likely environmental effects. In a letter in August this year Helion asked the NRC to “study and produce a report on design-specific licensing frameworks for mass-manufactured fusion machines”. It said because its 50 MWe magneto-inertial fusion device directly converts fusion energy to electricity, it would require less water abstraction and discharge. Its generators would be factory produced and assembled, without the need for radioactive material nor a licence during manufacturing – and it anticipates being able to mass- manufacture “as soon as the early 2030s”. It says, “The Part 30 framework is well suited to support


at-scale deployment... Nonetheless, at the right time, high-throughput, low-impact deployment of mass- manufactured fusion machines will require a more efficient alternative licensing process, that can be made available in parallel with traditional site-by-site licensing approaches. The company adds: “Even if scale deployment may be


a few years away, critical thinking about how the Part 30 framework can evolve to be ready – such as development of a “fusion generator registry” – should start now”. ■


www.neimagazine.com | November 2024 | 29


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53