X-energy Hires Fluor for Cascade Xe-100 Nuclear Island Engineering

X-energy has hired Fluor to engineer the nuclear island of Energy Northwest's proposed Cascade Advanced Energy Facility near Richland, Washington, X-energy said on Nov. 5. World Nuclear News puts the first phase at four 80 MWe Xe-100 reactors, 320 MWe in all. The contract value was not disclosed.

Fluor will handle engineering, design development, supply chain, estimating and project controls for the parts of the plant that hold the Xe-100 reactors and their supporting systems, X-energy said. The contract is between X-energy and Fluor; Amazon, which funds Cascade's feasibility phase under a development and funding agreement (according to X-energy's prospectus), is not named as a party. As Voltgrid's Oct. 29 project file set out, Amazon holds a right to buy power from the first four modules under a development and funding agreement, not a priced power contract.

The award gives Cascade's nuclear island its own engineer. Cascade Nuclear Partners, a joint venture of Kiewit Nuclear Solutions, Black & Veatch and Aecon, is Energy Northwest's progressive design-builder for the conventional island and for integrating requirements across the plant. It moves design work forward, but it is a services contract: Energy Northwest has announced no decision to build, and no construction permit application has been filed.

Fluor's Second Xe-100 Nuclear-Island Contract

This is the second nuclear-island engineering contract between the two companies. The first, which World Nuclear News dates to April, covers the proposed Xe-100 plant at Dow's Seadrift site in Texas, which X-energy is developing under the Department of Energy's Advanced Reactor Demonstration Program. X-energy says carrying that work over to Cascade is meant to cut long-term cost and schedule through a standard design.

The Xe-100 is a high-temperature gas-cooled reactor that runs on X-energy's TRISO-X fuel and is offered in four- or twelve-unit plants. World Nuclear News puts Cascade's first phase at 320 MWe, with room to grow to 12 units. Cascade is the first project in the X-energy and Amazon collaboration, whose goal is 5 GW of new nuclear by 2039; that is a goal, not contracted capacity.

What a Nuclear Island Is and Why It Is Split

The nuclear island is the part of a plant that holds the reactors and the systems that support them. X-energy says its Xe-100, an 80 MWe high-temperature gas-cooled reactor, needs far fewer safety-related systems than light-water designs, so most conventional-island and balance-of-plant systems can use commercial off-the-shelf parts.

That is why Cascade has two engineering teams: Fluor on the nuclear island for X-energy, and Cascade Nuclear Partners on the conventional island for Energy Northwest. X-energy says the split lets the partners advance different areas in parallel. It speeds design, not licensing: no construction permit application has been filed, and X-energy's target is the first half of 2027, ANS reported.

What Comes Next for Cascade's Permit Path

The NRC lists Cascade in pre-application review under docket 99902130 and refers only to a future construction permit application, with no date, on a project page last updated Sept. 23. X-energy expects that application in the first half of 2027, ANS Nuclear Newswire reported in August. Until then, the Fluor award changes the engineering timeline, not the licensing one: Cascade still needs an NRC construction permit, and a decision by Energy Northwest to build before any of its output reaches Amazon or the grid. The Dow plant is further along; its final safety evaluation was issued on Oct. 30, as Voltgrid reported.