DOE marks milestone as Xe-100 basic design completed

Maryland-based X-energy received an Advanced Reactor Concepts (ARC) award in 2015 to further develop its Xe-100 advanced reactor design and TRISO-X particle fuel. The project resulted in completion of the basic design of the reactor and fabrication of its first TRISO (tristructural isotropic) fuel pebbles using natural uranium at a pilot-scale fuel facility at Oak Ridge National Laboratory, which was commissioned as part of the project.

X-energy is now working to license the reactor design with the US Nuclear Regulatory Commission (NRC). It is also working to license and operate a HALEU fuel fabrication facility, with funding under the DOE's Advanced Reactor Demonstration Program (ARDP). The company's TRISO-X subsidiary in April selected a site for a fuel fabrication plant at the Horizon Center Industrial Park in Oak Ridge, with commissioning and start-up envisaged as soon as 2025. It plans to submit a reactor construction permit application to the NRC by the end of 2023, with the first reactor at a four-unit Xe-100 plant planned for construction at a site in Washington state to be operational by 2028.

"The Advanced Reactor Concepts award was the catalyst for X-energy's progress toward the deployment of the Xe-100 reactor and our TRISO-based fuel fabrication facility," said TRISO-X President Pete Pappano. The company's current ARDP award will complete the mission of putting carbon-free power on the grid while building the HALEU fuel supply chain for all advanced reactors, he added.

DOE is committed to supporting its industry partners in their efforts to deploy advanced reactors said DOE's Deputy Assistant Secretary for Reactor Fleet and Advanced Reactor Deployment Alice Caponiti. "X-energy has made tremendous strides in moving the Xe-100 design toward eventual deployment."

X-energy is one of two companies with advanced nuclear demonstration projects - the other being TerraPower, working towards the construction of a Natrium reactor in Kemmerer, Wyoming - which are now receiving support under the Bipartisan Infrastructure Law, signed into law in November 2021.

The Xe-100 is a pebble bed high-temperature gas reactor capable of a thermal output of 200 MW or (80 MW electrical). It uses fuel made from robust TRISO fuel particles which are able to withstand extremely high temperatures without melting. Optimised as a four-unit plant delivering 320 MWe, the reactor can provide baseload power to an electricity system or use its thermal output to support industrial applications with high pressure, high temperature steam.

X-energy recently signed a Letter of Intent with materials science company Dow to collaborate on the possible deployment of Xe-100 small modular reactor technology at one of Dow's manufacturing sites.