ML23335A033
| ML23335A033 | |
| Person / Time | |
|---|---|
| Issue date: | 11/30/2023 |
| From: | White A NRC/NMSS/DMSST |
| To: | |
| References | |
| Download: ML23335A033 (1) | |
Text
Navigating the Future Oversight of Fusion Systems Duncan White Office of Nuclear Material Safety and Safeguards November 30, 2023
U.S. Strategic Approach to Fusion:
Bold Decadal Vision
- Objectives:
o Realize an operating fusion pilot plant on a decadal timescale and prepare the path broadly to fusion commercialization and scale-up.
o Leverage fusion technologies to realize transformative civil, defense, and space capabilities and dominance.
o Identify strategic interagency collaborative opportunities.
- Key Basis Documents:
o National Academies of Sciences: Bringing Fusion to the U.S. Grid o U.S. Fusion Energy Sciences Advisory Committees long range strategic plan 2
Participating Agencies Department of Energy o
Lead agency in fusion energy R&D and coordinating the path to commercialization Department of State o
Coordination on international collaborations and cooperation Nuclear Regulatory Commission o
Fusion regulatory framework, licensing, and public engagement on public safety Department of Commerce o
Export control and standards National Science Foundation o
Partnerships on staffing & training and workforce development Department of Education o
Partnerships on fusion-related educational curricula Supporting Agencies: Department of Defense and NASA 3
Legislation and Commission Direction The Nuclear Energy Innovation and Modernization Act (NEIMA; Public Law 115-439) requires NRC to establish a technology inclusive regulatory framework for fusion energy systems by December 31, 2027 o
Definition of advanced reactor includes fusion reactor On April 13, 2023, the Commission issued SRM-SECY-23-0001 Options for Licensing and Regulating Fusion Energy Systems (ML23103A449) directing the staff to implement a byproduct material approach to regulating near-term fusion energy systems o
Modify existing 10 CFR Part 30 to include a Fusion Energy Systems framework o
Develop a new volume of NUREG-1556, Consolidated Guidance About Materials Licenses, dedicated to Fusion Energy Systems o
If a design presents hazards sufficiently beyond near-term technologies, staff should notify the Commission and make recommendations for appropriate action.
Oversight of fusion systems will be performed by both NRC and Agreement States 4
Characteristics of Near-Term Fusion Systems Safety focus of near-term fusion systems will be the control, confinement, and shielding of radioactive material present rather than on the performance and control of the device.
Near-term fusion systems are expected to have:
o Active engineered features to achieve a self-sustaining fusion reaction o No fissile material present and a self-sustaining neutron chain reaction is not possible o Energy and radioactive material production from fusion reactions cease without any intervention in off-normal events or accident scenarios o Active post shutdown cooling of the fusion device structures containing radioactive material is not necessary to prevent a loss of radiological confinement o Credible accident scenarios from any radionuclides present at the licensed facility are expected to result in low doses to workers and less than 1 rem effective dose equivalent to a member of the public offsite 5
U.S. Academic/Commercial Fusion Landscape Fusion Regulation and Regulatory Guidance Needed Now o Several academic/commercial fusion research and development facilities currently licensed by Agreement States o 25 commercial companies currently pursuing fusion in U.S. for energy, heat, propulsion, etc.
o Over $6 billion dollars in private investment o Two commercial companies currently constructing proof of concept fusion system facilities o Tokamak (magnetic) design currently under construction, operational by 2025 (CFS)
License application submitted to Agreement State o Field reverse configuration with magnetic confinement (magneto-inertial) design currently under construction, operational by 2025 (Helion)
Earlier prototype licensed by Agreement State, application for current design expected in 2024 Signed two purchase agreements to provide electricity by 2030 6
Fusion Basics 7
Deuterium (D - D)
Deuterium - Helium 3 (D - 3He)
Fusion Basics 8
Deuterium (2H)
Tritium (3H)
Neutron (1n)
Helium (4He) 3.5 MeV 14.1 MeV Captured in breeding blanket Exhaust Breeding Blanket
- 1. Shielding:
moderate and absorb neutrons to shield magnets
- 2. Heat Capture:
generate power
- 3. Tritium breeding:
Make more tritium for fuel (Lithium +
neutron)
Lawson Criteria To initiate a fusion reaction, you must confine the energy long enough in a fuel that is dense enough at a temperature that is high enough. The relationship that quantifies this is called the Lawson criterion.
Sources:
Horvath, A., Rachlew, E. Nuclear power in the 21st century:
Challenges and possibilities. Ambio 45, 38-49 (2016).
https://doi.org/10.1007/s13280-015-0732-y Figure 4 https://en.wikipedia.org/wiki/Lawson_criterion 9
Fusion is Hard: Status of the Technology and Performance Challenges 10
Three General Approaches to Fusion 11 Magnetic Continuous Magneto - Inertial Pulsed Inertial Pulsed
Commonwealth Fusion Systems
- Devens, MA
SPARC Facility at Commonwealth Fusion Systems https://cfs.energy/technology/sparc
https://www.helionenergy.com/technology/
Radiological Hazards Tritium Activation Products Neutrons Fusion Reactions (Fuel)
Deuterium - Helium 3 Deuterium - Deuterium (DD)
Proton - Boron 11 Design Elements Shielding Breeding Blankets System Controls (cryogenic, etc.)
Access Control, etc.
Programmatic Elements Radiation Protection Training Waste Management Accountability, etc.
Challenge - Diversity of Designs and Hazards under One Framework Fusion Technologies Magnetic Inertial Magneto-Inertial 22
Radioactive Material 23
- Tritium o
10 - 20 grams for R&D o
<500 grams for commercial o
HT or HTO is important for dosimetry
- Activation products o Quantity and Type unknown o
Highly dependent on selection of materials o
Area of extensive research o
Mostly in structural materials
- Dust o
Quantity and type dependent on inner wall o
Small metallic particles from plasma and inner vessel wall interactions o
Contains tritium and activation products o
Contributor to offsite doses 1 gram of tritium = 9620 curies
Scope of Fusion Rulemaking Activities Rulemaking:
- Based on 11e.(3) definition in AEA of byproduct material (statutory)
- Radioactive material for research, commercial or medical purposes
- Accelerator-produced
- Limited-scope rulemaking in Title 10, Part 30 of Code of Federal Regulations (10 CFR 30) to cover only near-term, known fusion energy system designs
- Definitions
- Content-of-application requirements specific to fusion - Use standard Part 30 processes where applicable
- Other fusion-specific requirements, as needed, to address specialized topics
- Agreement State regulations required to be compatible 24
Preliminary Proposed Rule Language Definitions in Parts 20 and 30 Approach for New and Amended Definitions
- Focus on byproduct material and associated radiation
- Emphasis on containing, processing, or controlling radiation and radioactive materials
- Limited to specific components - not facility-wide
- No impact on current licensees
- Enhance regulatory clarity and predictability 25
Preliminary Proposed Rule Language Content of Application in Part 30 Approach for Content of Application
- Supplement existing Part 30 regulations to address fusion system specific application o General description of fusion system o Operating and emergency procedures o Organization structure related to radiation safety o Training o Inspection and Maintenance o Material Inventory 26
Preliminary Proposed Rule Language Content of Application in Part 30 Approach for Content of Application - continued
- Alternative Approach o Radiation safety description of fusion system o Encourage pre-application communications
- Regulations are intended to apply to fusion systems during research and development or commercial deployment
- Issuance of license 27
Preliminary Proposed Rule Language Changes to Part 20 Approach for disposal of fusion systems byproduct material New construction materials potentially resulting in activation products consisting of different radionuclides and in different quantities than previously considered
- Waste streams not considered in the development of the Part 61 tables may require disposal
- Staff considering whether applications should include an assessment of the disposal pathway as part of the decommissioning funding plan Allow waste from fusion systems to be disposed at existing LLW disposal sites Use risk-informed approach based on site-specific intrusion assessment at LLW disposal facility to allow disposal of novel waste streams
- Does not require changes to Part 61
- Does not require changes to other sections and appendices in Part 20
- Consistent with LLW rulemaking currently underway 28
Scope of Fusion Rulemaking Activities
- Licensing Guidance:
o New NUREG-1556 licensing volume o
Well established structure - 21 volumes o Focus on topics that distinguish fusion from other uses of radioactive materials o Address range of fusion technologies o Technology-inclusive o Scale safety requirements o Use standard content from guidance documents to the extent possible o
NRC, Agreement State, and DOE o
No other licensing guidance development anticipated o Agreement State guidance required to be compatible
- Other Related Activities:
o Technology-specific implementation o Inspection guidance o Training for NRC and Agreement State staff o Public Outreach 29
Challenges - Regulatory and Guidance Development Several regulatory and safety issues need to be addressed during the rulemaking and guidance development process Sharing design approvals across the National Materials Program Composition of materials used in fusion systems o
Area of active research to minimize production of activation products and minimize radiation damage o
Radionuclides and quantities affect source term for emergency preparedness evaluation, decommissioning costs, waste disposal, maintenance and inspection protocols, etc.
Radiation safety o
Shielding of high energy neutrons and production of photons and x-rays o
Dosimetry considerations for gaseous tritium v. tritiated water (HTO) v. special tritiated products o
Worker protection during maintenance of vacuum vessel o
Tritium handling systems and containment of tritium contamination 30
Engagement and Outreach Leverage Existing Communication Avenues State-Tribal Communication letters Government-to-Government meetings Public Meetings User Groups Build Capabilities and Knowledge Workshops Seminars Training Staff rotations/details Engagement Timeframe Start of official rulemaking Middle of draft development After publication of proposed rule (official public comment period)
Meetings as needed Leverage Existing Regulatory Experience Agreement States Office of Regulatory Research (RES)
Department of Energy (DOE)
ARPA-E Standards Development Organizations (ASME, ANS)
International Diverse Stakeholder Engagement Agreement States Tribal Nations CRCPD OAS Federal Agencies Fusion Industry Association Professional Associations Utilities Universities International community Non-Government Organizations 31
Thank You!
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