artist rendering of X-Energy Xe-100 reactor design

Project Overview

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.

For more information, please see the Xe-100 reactor pre-application documents (NRC Docket 99902071).

To subscribe to the X-energy Xe-100 email service, select X-Energy Xe-100 from the Advanced Reactors list after entering your email into the GovDelivery system.

Pre-Application Activities

Product Type Reference Status
Xe-100 U.S. Regulatory Engagement Plan (REP) 2023 Update Regulatory Engagement Plan ML24054A840 No review requested
Quality Assurance Program Description, Revision 3 Topical Report ML20343A088 Feedback Provided
Mechanistic Source Term Verification and Validation  White Paper ML19283B524 Feedback Provided
Reactor Pressure Vessel Construction Code Assessment for the Xe-100 Reactor White Paper ML20202A598 Feedback Provided
Xe-100 Licensing White Paper: Use of Bounding Values White Paper ML21295A296 Feedback provided
Licensing Application Content and Regulatory Analysis White Paper ML21120A338 Feedback provided
TRISO-X Pebble Fuel Qualification Methodology Topical Report ML21246A289 Feedback provided ML22327A199
Maintenance Staff Optimization Approach White Paper ML21362A751 Feedback provided
Physical Protection System Approach White Paper ML22098A228 Feedback provided
Risk-Informed Performance-Based Licensing Basis: X-energy's Approach to NEI 18-04 Implementation Topical Report ML22187A279 Feedback provided ML22308A197
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Graphite Qualification Methodology Topical Report ML22304A197 Withdrawn, but feedback was provided in ML23023A248 and ML23033A544.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 Licensing Topical Report ML22195A260 (Revision 1)

ML23181A172 (Revision 2)

ML24047A308 (Revision 3)
Under review
Probabilistic Risk Assessment Technical Adequacy Approach White Paper ML22318A236 Feedback provided:
Quality Assurance Program Description, Revision 4, supplemented by Quality Assurance Program Description, Revision 6 Topical Report ML22230D075
Under review
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 provided
Atmospheric Dispersion and Dose Calculation Methodology Topical Report ML23268A454 Under Review
GOTHIC and Flownex Analysis Codes Qualification Topical Report ML23275A201 (Revision 1)
ML24143A192 (Revision 2)
Revision 1 – Withdrawn

Revision 2 – Under Review
Training Programs Methodology Topical Report ML24089A243 Under Review
Reactor Core Design Methods and Analysis Topical Report ML24099A183 Under Review
Transient and Safety Analysis Methodology Topical Report ML24121A285 Under Review
Mechanistic Source Term Approach Topical Report ML24131A146 Under Review