Tracker · Pre-application
X-Energy, LLC (XE-100)
The U.S. Nuclear Regulatory Commission (NRC) is currently engaged in pre-application activities with X Energy, LLC. (X-energy) starting in September 2018. X-energy is a Rockville, MD company designing the Xe-100 reactor which is a pebble-bed, high-temperature gas-cooled reactor (HTGR). Each reactor will generate 200MWt and approximately 80MWe. The standard Xe-100 "four-pack" plant generates approximately 320MWe.
- Who
- Not stated
- Design
- Xe-100
- Reactor type
- High Temperature Gas Reactors
- Status
- Active on the NRC index
- What
- Not stated
- When
- Not stated
- Site
- Not stated on the NRC page in this snapshot.
- NRC page reviewed
- Tuesday, September 15, 2026
Dockets
Status timeline
Dates are printed as the NRC page prints them, including the actual (A) or target (T) mark.
The NRC page in this snapshot does not list a milestone table.
NRC activity table
| Product | Type | Reference | Status |
|---|---|---|---|
| Xe-100 U.S. Regulatory Engagement Plan (REP) 2023 Update | Regulatory Engagement Plan | ML19177A398 | No review requested |
| Quality Assurance Program Description, Revision 3 | Topical Report | ML20343A088 | Feedback ProvidedML20233A910ML20351A428 |
| Mechanistic Source Term Verification and Validation | White Paper | ML19283B524 | Feedback ProvidedML20069C346 |
| Reactor Pressure Vessel Construction Code Assessment for the Xe-100 Reactor | White Paper | ML20202A598 | Feedback ProvidedML21166A304 |
| Xe-100 Licensing White Paper: Use of Bounding Values | White Paper | ML21295A296 | Feedback providedML21323A159 |
| Licensing Application Content and Regulatory Analysis | White Paper | ML21120A338 | Feedback providedML21271A629 |
| TRISO-X Pebble Fuel Qualification Methodology | Topical Report | ML21246A289 | Feedback provided ML22327A199 |
| Maintenance Staff Optimization Approach | White Paper | ML21362A751 | Feedback providedML22095A057 |
| Physical Protection System Approach | White Paper | ML22098A228 | Feedback providedML22269A562 |
| Risk-Informed Performance-Based Licensing Basis: X-energy's Approach to NEI 18-04 Implementation | Topical Report | ML22187A279 | Feedback provided ML22308A197ML22340A564 |
| Transient and Safety Analysis Methodologies Framework | Topical Report | ML21288A173 | Feedback provided: ML23086C082 |
| Control Room Staffing Analysis Methodology | Topical Report | ML22004A333 | Feedback provided in ML23004A128 and ML23107A063. |
| Training Programs, Control Room Operator Qualification, and Control Room Operator Eligibility | White Paper | ML22153A201 | Feedback provided ML22294A105 |
| Graphite Qualification Methodology | Topical Report | ML22304A197 | Withdrawn, but feedback was provided in ML23023A248 and ML23033A544. |
| Xe-100 Principal Design Criteria | Topical Report | ML22195A260 | Feedback provided |
| Probabilistic Risk Assessment Technical Adequacy Approach | White Paper | ML22318A236 | Feedback provided:ML23097A124 |
| Quality Assurance Program Description, Revision 4, supplemented by Quality Assurance Program Description, Revision 6 | Topical Report | ML22230D075 | Feedback providedML24218A128 |
| Xe-100 Training Program Methodology (Revision 2) | Topical Report | ML22364A278 | Withdrawn, but feedback was provided in ML23103A187. |
| Xe-100 Plant Control and Data Acquisition System | White Paper | ML23048A309 | Feedback provided ML23236A008 |
| Xe-100 Seismic Design Methodology | White Paper | ML23044A310 | Feedback provided ML23188A092 |
| Emergency Planning Approach and Regulatory Analysis | White Paper | ML23240A744 | Feedback providedML23324A106 |
| Atmospheric Dispersion and Dose Calculation Methodology | Topical Report | ML23268A454 | Feedback providedML24242A251 |
| GOTHIC and Flownex Analysis Codes Qualification | Topical Report | ML23275A201 | Revision 1 – WithdrawnRevision 2 - Feedback provided - ML25204A205 |
| Training Programs Methodology | Topical Report | ML22364A278 | Revision 2 – WithdrawnFeedback provided - ML25080A206 |
| Reactor Core Design Methods and Analysis | Topical Report | ML24099A183 | Feedback provided - ML25094A140 |
| Transient and Safety Analysis Methodology | Topical Report | ML24121A285 | Feedback provided - ML25206A049 |
| Mechanistic Source Term Approach | Topical Report | ML24131A146 | Feedback provided - ML25195A103 |
| Graphite Core Assembly Material Qualification and Design Methodologies | Topical Report | ML24306A125 | Under Review |
| Plume Exposure Pathway Emergency Planning Zone Sizing Methodology | Topical Report | ML24331A305 | Feedback provided - ML26034C377 |
| Use of Remotely Operated Special Tooling as Part of the Spent Fuel Storage System | White Paper | ML26023A101 | Under Review |
| Approach to Meeting Self-Reliant Mitigation Facility Operating and Technical Characteristics | White Paper | ML25248A306 | Feedback Provided - ML25339A166 |
Related Federal Register notices
Included when a notice shares a docket printed on the NRC page, or when the notice title repeats the project or design name. Other NRC notices are left out.
No in-scope Federal Register notice is linked to this project.