- Advanced Reactor Conceptual Design
X-energy is developing a 200-MWth pebble-bed, high-temperature, gas-cooled advanced reactor (HTGR), called the Xe-100. Our team provided conceptual design engineering services, civil structural analysis and modeling support for the initiative. We assisted with X Energy’s HTGR and fuel form trade study, and performed a civil structure trade study.
The preconceptual design of the Xe-100 civil structure is based on the design of the 350 MWt SC-MHR. The SC-MHR civil structure was scaled to accommodate the lower power level of the Xe-100 reactor. Since X-energy is embarking on the conceptual design, it is important to establish a reference concept for the plant site and the principal structures of the Xe-100 nuclear island (NI). The preconceptual civil structure design serves as a good starting point, but our team's role included reevaluating the design needs and updating accordingly.
We assisted with the HTGR and fuel form trade study to evaluate the impact reactor size will have on cost, schedule and risk. Our services for the trade study included:
- Review of X-energy’s trade study looking at the impact of reactor size and fuel type (i.e. pebble vs. prismatic block fuel) on the business case viability.
- Consultation in the areas of engineering, procurement and construction (EPC) costing, schedule and conceptual development.
- Advised on the development of EPC schedules and preliminary identification of the risk profile for major elements of the schedule.
- Reviewed and provided input on installation costs for specific items based on size and complexity.
We provided X-energy with a civil structure trade study for the Xe-100. Our services for the trade study included:
- Develop high-level functional requirements for building and site.
- Develop the conceptual Xe-100 site layout considering the requirement for modular construction.
- Develop a preconceptual design of the principal NI buildings and structures for the Xe-100 plant.
- Perform a feasibility analysis of embedding the RB.
- Perform a constructability evaluation of the RB, potential construction techniques, and the benefits and disadvantages of each option.
- Propose ways to optimize the plant security design with the goal to reduce the required security force.
We provided the following deliverables:
- Civil structure trade study report, including proposed NI layout describing the preferred options and respective rationales, embedment analysis of the RB, the proposed construction methods, and preliminary cost estimates (AACE Class 5).
- General arrangement drawings, including the NI and site layout plans.
Our scope of services for the civil structural analysis and modeling included:
- Dynamic models of reactor components
- Dynamic model of reactor system including building structure
- Detailed physical models used in forming the dynamic models where appropriate
- Enveloping seismic load conditions with justification
- Generic soil conditions used in seismic analysis
- Schedule review
- Cost estimates
- Conceptual designs
- Trade studies