SGL Carbon Advances Graphite Billet Production for High-Temperature Gas-Cooled Reactors

(IN BRIEF) SGL Carbon and X-energy have announced a binding agreement to double SGL Carbon’s production capacity for NBG-18, a nuclear-grade graphite material used in X-energy’s Xe-100 high-temperature gas-cooled reactor. Under the agreement, X-energy will invest up to $8 million in milestone-based payments to support new facilities and equipment upgrades at SGL Carbon’s Chedde, France site. The expansion will enable production of graphite billets for up to eight Xe-100 reactors per year. The agreement builds on a 10-year Supplier Framework Agreement established in January 2026, which included an initial three-year award worth more than $100 million for X-energy’s first commercial projects. NBG-18 is used as a neutron moderator and structural component in the Xe-100’s pebble-bed core. Initial production is intended to support X-energy’s proposed four-unit Xe-100 deployment with Dow Chemical Company under the U.S. Department of Energy’s Advanced Reactor Demonstration Program.

(PRESS RELEASE) WIESBADEN, 4-Aug-2026 — /EuropaWire/ — SGL Carbon and X-energy have announced a binding agreement to double SGL Carbon’s production capacity for medium-grain isotropic graphite, known as NBG-18, a nuclear-grade graphite material used in X-energy’s Xe-100 high-temperature gas-cooled reactor.

The agreement is intended to expand the supply chain for graphite billet production and support X-energy’s commercial project pipeline.

Under the agreement, X-energy will invest up to $8 million through milestone-based payments to support new facilities and equipment upgrades at SGL Carbon’s site in Chedde, France.

The investment will enable the Chedde facility to produce graphite billets for up to eight new Xe-100 reactors per year.

SGL Carbon has also agreed to expand capacity in the United States for machining billets into graphite blocks, supporting greater supply chain continuity for a safety-critical material.

If fully executed, the agreement would double European manufacturing capacity for NBG-18 by 2030.

Additional capacity investments are also being considered across several regions to further reduce bottlenecks in initial billet production.

The capacity expansion builds on a 10-year Supplier Framework Agreement established between SGL Carbon and X-energy in January 2026.

That framework included an initial three-year award valued at more than $100 million for X-energy’s first commercial projects.

The first NBG-18 graphite blocks produced under that award at SGL Carbon’s Chedde site have already been shipped to SGL sites in the United States for machining into components.

This follows a successful prototyping campaign that began earlier this year.

The campaign included non-nuclear testing and validation at X-energy’s Technology and Advancement Center in Frederick, Maryland, ahead of final production.

Clay Sell, CEO of X-energy, said commercialising new nuclear energy at scale depends first on significantly expanding the new nuclear supply chain.

He said this challenge extends beyond any single company, supplier or country.

Sell added that X-energy looks forward to advancing the work with SGL Carbon and engaging with potential partners that share its vision for a robust and resilient U.S. and allied nuclear supply chain.

Andreas Klein, CEO of SGL Carbon, said the joint expansion of nuclear-grade graphite production capacity reinforces the importance of the partnership with X-energy and helps ensure reliable supply.

He said the agreement is strategically important for SGL Carbon because it strengthens the company’s position in the specialised growth market for nuclear-grade graphite.

Klein added that the deal underscores the importance of SGL Carbon’s graphite expertise for safety-critical applications and opens up opportunities for further growth.

NBG-18 is central to the Xe-100 reactor design.

It functions as both a neutron moderator and a structural component of the reactor’s pebble-bed core.

The material was originally developed for South Africa’s Pebble Bed Modular Reactor programme and later for the U.S. Department of Energy’s Next Generation Nuclear Plant project.

Both programmes are direct predecessors to X-energy’s Xe-100 reactor.

Through these earlier programmes, as well as X-energy’s and SGL Carbon’s own initiatives, NBG-18 has undergone extensive qualification work for commercial nuclear operation.

The material has gathered operational data intended to validate its performance over decades of high-temperature operation.

Initial NBG-18 production is intended to support X-energy’s first commercial deployment of the Xe-100 reactor.

That project is a proposed four-unit plant being developed in partnership with Dow Chemical Company under the Advanced Reactor Demonstration Program of the U.S. Department of Energy.

Additional capacity is being secured for follow-on projects to support manufacturing readiness for safety-critical, long-lead materials.

SGL Carbon’s partnership with X-energy forms part of a broader portfolio of experienced suppliers supporting deployment of the Xe-100 and the development of a global industrial supply chain.

X-energy is a developer of advanced small modular nuclear reactors and fuel technology.

The company’s Xe-100 high-temperature gas reactor and TRISO-X particle fuel are designed to support clean, safe and reliable energy applications.

X-energy has commercial projects under way with Dow, Amazon and Centrica across grid, industrial and artificial intelligence applications.

Through the capacity expansion agreement, SGL Carbon and X-energy are strengthening a critical materials supply chain for advanced nuclear deployment and supporting the industrial readiness required for commercial-scale small modular reactor projects.

About X-energy

X-energy, Inc. is a leading developer of advanced small modular nuclear reactors and fuel technology designed to establish a new standard in clean, safe, reliable energy. X-energy’s intrinsically safe Xe-100 high-temperature gas reactor and TRISO-X particle fuel expand applications for nuclear technology, with commercial projects underway with Dow, Amazon, and Centrica across grid, industrial, and AI applications. Together, X-energy’s technology drives enhanced safety, lower cost, faster construction timelines, and scalable deployment when compared with other SMRs and conventional nuclear.

About SGL Carbon

SGL Carbon is a technology-based company and one of the world’s leading manufacturers of carbon-based solutions. Its materials and products made from specialty graphite, highperformance fibers, and composite materials serve the most demanding applications in many

industries that are shaping the future: mobility, semiconductor technology, LEDs, energy generation, aerospace, and fuel cell manufacturing. SGL Carbon also develops forward-looking and reliable solutions for the chemical industry, numerous industrial applications, and, increasingly, the defense industry.

With approximately 3,800 employees at 28 locations in Europe, North America, and Asia, SGL Carbon generated revenue of 850 million euros in fiscal year 2025.

Further information about SGL Carbon can be found at www.sglcarbon.com/presse.

Important note:

To the extent that our press release contains forward-looking statements, the latter are based on information that is available at present and on our current forecasts and assumptions. Forward-looking statements, by their very nature, entail known as well as unknown risks and uncertainties that may lead to actual developments and events differing substantially from the forward-looking assessments. Forward-looking statements must not be understood to be guarantees. Instead, future developments and events depend on a large number of factors; they comprise various risks and imponderables and are based on assumptions that may possibly turn out not to be appropriate. These include unforeseeable changes to fundamental political, economic, legal and societal conditions, particularly in the context of our main customers’ industries, the competitive situation, interest and exchange rate trends, technological developments as well as other risks and uncertainties. We perceive additional risks e.g. in pricing developments, unforeseeable events in the environment of companies acquired and Group member companies as well as in current cost savings programs from time to time. The SGL Carbon assumes no obligation and does not intend to adjust or otherwise update these forward-looking statements either.

SGL Carbon SE

Claudia Kellert – Head of Investor Relations,
Communications and Corporate Sustainability
Soehnleinstrasse 8
65201 Wiesbaden/Germany
Telephone +49 611 6029-100
Fax +49 611 6029-101
press@sglcarbon.com
www.sglcarbon.com

SOURCE: SGL Carbon

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