TerraPower names Hyundai E&C as EPC for up to eight Natrium reactors

TerraPower has selected Hyundai Engineering & Construction as engineering, procurement and construction contractor for up to eight future Natrium reactors — with completion, price and performance guarantees — and signed a term sheet with SK Innovation to develop Korea's first commercial Natrium plant. The guarantees are the story: they are the contractual mechanism conventional lenders have always demanded and nuclear construction has rarely offered.

Key facts

• TerraPower announced both agreements on August 14, 2026, during a Seoul visit by founder and Chairman Bill Gates and President and CEO Chris Levesque.
• The HDEC framework agreement covers up to eight future Natrium reactors across the United States and select international markets, with completion, price and performance guarantees intended to enable conventional commercial financing.
• The SK Innovation term sheet targets Korea's first commercial Natrium plant, plus collaboration on digital twin technology and artificial intelligence for operations and maintenance.
• The Natrium design pairs a 345 MWe sodium-cooled fast reactor with molten salt storage that can boost output to 500 MW for more than five hours.
• TerraPower already holds a commercial agreement with Meta for up to eight Natrium plants, signed January 9, 2026, with initial units targeted as early as 2032.

What happened

TerraPower's leadership spent August 14 in Seoul, where Gates and Levesque met Prime Minister Han Seong-sook and leaders from the Export-Import Bank of Korea, HD Hyundai, HDEC and SK Innovation. Two agreements followed.

The first is a framework agreement making HDEC the EPC contractor for up to eight future Natrium reactors. TerraPower says the deal is structured around completion, price and performance guarantees and is intended to streamline costs, improve design and construction efficiency, and strengthen global supply chains for a fleet of Natrium plants in the United States and select international markets, according to the company's announcement.

The second is a term sheet with SK Innovation formalizing intent to develop Korea's first commercial Natrium plant and to expand internationally. The companies plan to explore engineering and digital collaboration, including digital twins and AI tools for optimizing operations and maintenance.

"Combining TerraPower's innovative advanced nuclear technology with Korea's nuclear construction and operational expertise will strengthen our global cooperation and accelerate the deployment of a Natrium fleet," Levesque said in the announcement. World Nuclear News confirmed the agreements cover commercialization across the USA, Korea and select international markets.

Why it matters

Nuclear construction in the West has not customarily come with meaningful completion and price guarantees. Vogtle's overruns landed on utility balance sheets and ratepayers; the first Natrium unit at Kemmerer is backed by the Department of Energy's Advanced Reactor Demonstration Program. A fleet financed by ordinary project lenders requires someone creditworthy to own construction risk. That is precisely what TerraPower says this agreement does — and why the announcement reads less like a construction contract and more like a financing instrument.

The choice of counterparty follows the same logic. Korean EPC firms carry the industry's strongest recent record for on-time, on-budget nuclear delivery, anchored by the UAE's four-unit Barakah program. TerraPower is effectively importing that delivery model for its fleet — while Bechtel remains the EPC contractor building Kemmerer Unit 1. This is a bifurcation of the supply chain for scale, not a replacement.

The demand side already exists on paper: the Meta agreement provides funding support and rights covering up to eight Natrium plants — up to 2.8 GW of baseload, boostable to 4 GW — with initial units as early as 2032. Guaranteed-price construction is the missing piece that turns such offtake interest into bankable projects.

Background

This is the third escalation of TerraPower's Korea strategy in 2026. In January, Korea Hydro & Nuclear Power joined TerraPower's investor base. In May, TerraPower signed manufacturing agreements with HD Hyundai, naming its shipbuilding arm preferred manufacturer for the Natrium Reactor Enclosure System. The HDEC and SK Innovation agreements extend that supply-chain relationship into construction delivery and plant ownership.

Meanwhile the first Natrium plant is under construction at Kemmerer, Wyoming, with completion expected in 2030 — the first utility-scale advanced nuclear plant in the United States. TerraPower was also accepted into INPO in July, the first advanced-reactor company inside the industry's safety-culture institution. NNN's SMR hub tracks the broader deployment race.

What's next

Watch for three concretions: a definitive EPC contract with named units and sites under the HDEC framework; a siting and licensing pathway for the SK Innovation plant in Korea, where regulatory treatment of a sodium-cooled fast reactor will be first-of-a-kind; and whether the guarantee structure survives into signed, financeable contracts at specific projects. TerraPower says work under both agreements begins now. The company's stated fleet targets — Meta units from 2032, deployment across three markets — will test whether guaranteed-delivery nuclear construction can scale beyond a press release.