X-energy and SGL Carbon to Expand Nuclear-Grade Graphite Production Capacity

X-Energy and SGL Carbon announced on August 3 that they have signed a binding agreement to expand production capacity for NBG-18 medium-grained isotropic nuclear-grade graphite. NBG-18 is a critical specialty material for X-Energy's Xe-100 high-temperature gas-cooled reactor, supporting the company's subsequent commercial project deployments.

Under the agreement, X-Energy will invest up to $8 million in phases to support the construction of new facilities and equipment upgrades at SGL Carbon's plant in Chedde, France. Upon completion of the expansion, the plant will be capable of producing graphite billets annually sufficient for up to eight Xe-100 reactors. SGL Carbon has also agreed to expand its graphite billet processing capacity in the United States to enhance the stability of this safety-critical material supply chain.

The two companies stated that, upon full implementation of the agreement, European NBG-18 production capacity will double by 2030. The companies are also evaluating the possibility of additional capacity investments in multiple regions to alleviate bottlenecks in the initial graphite billet production stage.

This capacity expansion arrangement builds on the 10-year supplier framework agreement signed by the two companies in January 2026. The framework agreement includes an initial contract valued at over $100 million over three years to support X-Energy's first commercial projects. The first batch of NBG-18 graphite billets produced in France under this contract has been shipped to SGL Carbon's U.S. plant for component processing. Previously, X-Energy had conducted non-nuclear testing and validation at its Technology Development Center in Frederick, Maryland, in preparation for subsequent production.

NBG-18 nuclear-grade graphite is a core material in the Xe-100 design, serving both as a neutron moderator and as a structural component of the pebble-bed core. The material was originally developed for the South African Pebble Bed Modular Reactor project and was later adopted by the U.S. Department of Energy (DOE) Next Generation Nuclear Plant program. These projects share a lineage with X-Energy's Xe-100 technology pathway and have accumulated material qualification and operational performance validation data for NBG-18.

The initial NBG-18 production plan will serve the first commercial deployment of the Xe-100, being advanced by X-Energy in partnership with Dow. This project is part of the DOE Advanced Reactor Demonstration Program and plans to construct a nuclear facility consisting of four reactor units, with some production capacity reserved for subsequent projects to support the manufacturing preparation of long-lead-time safety-critical materials.

X-Energy stated that achieving scaled commercial deployment of advanced nuclear energy requires the simultaneous expansion of critical equipment and material supply capabilities. SGL Carbon stated that expanding nuclear-grade graphite production capacity will help ensure a stable supply for X-Energy projects and strengthen its business position in the nuclear-grade graphite market.