So You Want to Build a Nuclear Reactor
Source: https://www.youtube.com/watch?v=89KYlEzW5_M
So You Want to Build a Nuclear Reactor
Brief
Professor David Rusic (Illinois Energy Prof) gives a presentation-style update on U.S. small modular reactor (SMR) progress, focusing on the two DOE-backed winners from the 2020 competition: X‑energy’s TRISO-fueled pebble-bed design and TerraPower’s Natrium sodium‑cooled reactor with molten‑salt thermal storage. He explains TRISO fuel as microscopic kernels coated with carbon/ceramic shells, assembled into golf‑ball‑size pebbles that permit continuous on-line refueling and strong containment of fission products; high neutron energies in these fourth‑generation concepts enable transmutation of long‑lived wastes. Natrium uses a sodium coolant and external molten‑salt storage so a plant can run continuously while dispatching electricity on demand from stored heat. Rusic walks through the multi‑year, capital‑intensive permitting sequence (site ownership, environmental impact statement, NRC preliminary safety analysis — ~1,700 pages for Natrium — non‑nuclear and nuclear construction permits, as‑built documentation, then operating license). He names sites and partners: Natrium’s Wyoming coal‑to‑nuclear conversion (Amazon committed as offtaker) and X‑energy’s Seadrift, Texas project adjacent to Dow Chemical, with X‑energy’s TRISO fuel assembly facility planned near Oak Ridge, TN. He judges Natrium’s schedule as potentially operational by 2029 (grid delivery ~2031) and X‑energy likely later (optimistic 2029, more likely ~2032), noting fuel‑fabrication and licensing remain key bottlenecks.
Why it matters
The 2020 U.S. DOE advanced reactor competition picked two winners: X-energy (a TRISO-fueled pebble-bed SMR) and TerraPower’s Natrium (a sodium-cooled SMR with molten-salt heat storage).
Key details
- X-energy’s design uses TRISO fuel: microscopic fuel kernels with carbon/ceramic coatings (described as 'grain-of-sand' kernels assembled into golf-ball-size pebbles), enabling continuous pebble refueling and very high outlet temperatures for both electricity and process heat.
- TerraPower’s Natrium is a sodium‑cooled fast-spectrum reactor paired with a molten-salt thermal storage system; its chosen site is a former coal plant in Wyoming, it has an accepted environmental impact statement and a non‑nuclear construction permit, and the project team has submitted a ~1,700‑page Preliminary Safety Analysis Report to the NRC.
- Commercial partners and funding: the DOE program provides major funding; Amazon has invested in the Natrium project and agreed to offtake electricity for AWS data centers; Dow Chemical is investing in the X‑energy Seadrift, Texas site to transition a chemical plant from coal to nuclear heat/electricity.
- Licensing and timeline realities: building an SMR requires site selection, environmental review, multi-stage NRC approvals (non‑nuclear construction permit → PSAR review → nuclear construction permit → final as‑built report → operating license). Professor Rusic estimates Natrium could be operational by 2029 with grid power around 2031; X‑energy and its TRISO fuel manufacturing (planned near Oak Ridge, TN) are on a longer path—optimistic target 2029 but more likely ~2032.