MMR
US
Basics
Reactor Type
Gas Cooled Reactor
Gas cooled reactor
Primary heat transport: mostly CO2 or helium gas
Primary heat transport: mostly CO2 or helium gas
Reactor Description
High temperature prismatic GCR
HTGR fuel element form consisting of prismatic blocks
Primary heat transport: helium gas
Primary heat transport: helium gas
Electric Output (MWe)
5 - 10
Thermal Output (MWt)
15 - 30
Size
Micro
'Micro' size
Electric output of less than 10 MWe
Electric output of less than 10 MWe
Spectrum
Thermal
Kinetic neutron energy of 0.000…0.025 eV
Slow or cold neutron / moderated neutron spectrum
Slow or cold neutron / moderated neutron spectrum
Developer
Ultra Safe Nuclear Corporation
Pilot Site Details
Chalk River Laboratories, Ontario
Details
Use (goal of commercial operation)
electricity, heat, hydrogen
Deployment medium
Land-based
Design Lifetime (Years)
20
Fuel
Fuel class
HALEU
High-assay low enriched uranium
Uranium enriched to 5…20 percent U-235
Uranium enriched to 5…20 percent U-235
Fuel Type
TRISO Prismatic
Tristructural isotropic (nuclear fuel)
Fuel elements consisting of prismatic blocks
Fuel elements consisting of prismatic blocks
Fuel Cycle
N/A
Refuelling Cycle
N/A
Cooling & Temperature
Reactor cooling of primary loop
Helium
Reactor moderator
Graphite
Crystalline allotrope of element carbon
Special quality characteristics as moderator
Special quality characteristics as moderator
Reactor Outlet Temperature (°C)
630
Status
Design status
Preliminary design
Licensing status
- 2021 - Started initial engagement plant...
- 2021 - Started initial engagement plant with US regulator NRC
- 2019 - Started phase 2 of VDR in Canada
- 2017 - Started pre-licencing vendor design review (VDR) in Canada
Deployment timeline
- 2026 - Target demonstration project...
- 2026 - Target demonstration project construction
Agreements and Engagement
- Dec 2025 - Nano Nuclear Energy to...
- Dec 2025 - Nano Nuclear Energy to acquire major assets of the bankrupt USNC
- Oct 2024 - USNC filed for Chapter 11 bankruptcy in US, pledged to maintain full operational continuity across its projects
- Nov 2023 - Agreement for fuel joint venture with Framatome
- Nov 2023 - Agreement signed with Philippines' Manila Electric Company for MMR deployment
- Jun 2023 - Gadsden, Alabama, site announced for MMR assembly factory
- Mar 2023 - USNC and Polish chemical company Grupa Azoty Polic signed agreement to develop and build an MMR-based nuclear energy research facility
- Mar 2023 - Agreement with Urenco for LEU+ supply
- Aug 2022 - Agreement with Hyundai Engineering to support procurement of materials and services for global deployment of MMR
- Mar 2022 - USNC announced 5-year investment at Oak Ridge National Lab into TRISO fuel manufacturing
