InvestmentsThe NRC issued a construction permit for TVA’s 300 MWe BWRX-300 at Clinch River in September, 14 months into the review and four months early 📅. NRC Chairman Ho Nieh called it what “the new NRC looks like.” Yet as of the announcement, TVA had not disclosed a construction start date or a project value ⚡. That gap is the story. A permit is a date on the regulator’s calendar. First nuclear concrete, fuel load, and the first megawatt-hour sit on the company’s calendar, and those dates keep moving.
So which dates in your tracker belong to a regulator, and which belong to the company? The rest of this piece sorts them.
Sort the milestone before you trust the date
Companies use one word for events that carry very different risk. Take criticality. Four DOE-authorized test reactors reached it by July 4: Antares Mark-0, Valar Atomics Ward 250, Deployable Energy Unity, and Aalo-X 🚀. Aalo’s was a zero-power, full-scale core of a planned 10 MWe unit. DOE itself says the work lays a basis for reactors that produce electricity in 2027 and beyond. That is real progress, and it is not a power plant.
A rough ladder, from cheapest to hardest to fake 📈:
Design review statements. The UK’s ONR issued a GDA statement for the BWRX-300 in December 2025, and Holtec’s SMR-300 cleared Step 2 in March 2026.
Construction permits. They allow nuclear construction to start. They do not allow operation, and TVA and TerraPower both still need separate operating licences.
Final investment decisions. This is when money gets committed. OPG took its decision on the first Darlington BWRX-300 on May 8, 2025.
Physical progress. Nuclear concrete, installed modules, fuel on site. Hardest to fake, and the dates people ignore.
The regulator is no longer the slow part
TerraPower filed for its 345 MWe Natrium sodium-cooled reactor in March 2024. The NRC cut its review from 26 months to 19, finished the safety review in December 2025, and voted the permit on March 4, 2026 ⏱️. That is two years from filing to permit for a non-light-water design, which the NRC had not done for a commercial reactor in four decades.
Dow and X-energy are next in line. The NRC finished its environmental assessment for the Xe-100 project in Seadrift, Texas, in May, with a finding of no significant impact, and X-energy expects safety recommendations in November. The company’s own filings put construction in the first half of 2027, after the permit arrives, with operations in the early 2030s.
Compare that with the company-side date. TerraPower still says Kemmerer finishes in 2030, while Nuclear Engineering International notes that a 2031 start-up may be optimistic with the nuclear island only now going up 🏗️. The UK shows the same split. Rolls-Royce SMR’s 470 MWe PWR was targeting the end of GDA Step 3 in August 2026, and the sources reviewed here do not confirm completion, so treat that status as possibly stale.
Three checks sort a regulator-driven date from a hopeful one:
Is there a docketed review with a published schedule behind the date?
Does the site already hold an early site permit? Clinch River’s covers 800 MWe, which is why its review ran short.
Does the company’s date quietly assume the regulator finishes early again?
Follow the money to the signature
NuScale is the cleanest example. ENTRA1 Energy and TVA signed an agreement in September 2025 for up to 6 GW. NuScale management later described it as 72 modules across six plants. It is not a power purchase agreement. In May, management expected a PPA later this year. On the August call, talks were still running, and CEO John Hopkins was floating 6 to 8 GW 💰. The scope grew before the contract existed.
Holtec is more candid in print. Its S-1 filing says Pioneer One and Two could be significantly delayed if definitive offtake agreements do not materialize. What it has today is a binding framework agreement. The 2023 plan targeted mid-2030 for the first unit at Palisades. Current language says early 2030s, and Holtec is still completing a Class 2 construction estimate.
The context that makes news like this meaningful is exactly what SMRbrief Pro was built to provide. Whatever source you use, rank commercial signals by how much they bind the parties 📝:
Signed PPA beats framework agreement beats MOU.
Named financing beats “discussions with institutions.”
A dated FID beats a “targeted” FID. Romania’s 462 MW NuScale project was flagged in August 2025 as possibly slipping to early 2027, so check it.
Unannounced scope changes are a warning, not good news.
Fuel, factories, and funding cliffs
Fuel hides inside reactor dates. Natrium needs HALEU metallic fuel, and a TerraPower and GE Hitachi joint venture is building that supply at a Wilmington, North Carolina facility. X-energy’s TX-1 TRISO fuel plant in Oak Ridge has a licence and vertical construction underway, with completion expected in the first half of 2028 🔬. The reactor is not the only critical-path item, and the fuel plant often has its own, later date.
Funding has deadlines too. X-energy’s S-1 notes that construction activity after 2030 would not qualify for ARDP reimbursement without a change to the DOE award. A slip of one year can cost money, not only time ⚠️.
For a benchmark that worked, look at Ontario. OPG finished the Darlington refurbishment four months early and C$150 million under budget, then priced the first BWRX-300 at C$7.7 billion: C$6.1 billion for the reactor and C$1.6 billion for systems shared across all four units. The reactor foundation was lifted into place in May 2026, with completion targeted for the end of 2030. A utility with a delivery record, a fixed price, and a construction licence is the standard the others get measured against.
What to do with the dates
Treat every timeline as a stack of separate promises, each owned by a different party.
Write down who controls each step: regulator, company, customer, lender, fuel supplier.
Trust dates with a docket number. Discount dates with only a press release.
Track drift. Holtec’s first unit moving from mid-2030 to early 2030s is data.
Reset your expectations after each FID and each cost estimate, because those are where schedules get honest.
Which 2030 date on your watchlist has a signed offtake agreement and a funded fuel supply behind it?