These trackers make claims about who is building what, how far along they are, and who has agreed to buy it. This page explains where those claims come from, what qualifies for inclusion, and where the numbers are deliberately more conservative than the headlines you will read elsewhere.
The Second Atomic Age is an independent, non-commercial set of trackers and tools following the advanced-nuclear buildout in the United States — the designs racing to first criticality, the pipeline from demo to deployment, where reactors are actually being sited, who has contracted for power, and the fuel-cycle supply chain being rebuilt around them.
It is a reporting and reference project, not a consultancy, not a research service, and not affiliated with any reactor developer, utility, investor, or government body.
Every tool on this site reads from one internally maintained dataset, covering reactor designs, companies, pilot-program milestones, sites, deployments and offtake agreements, economics, the fuel-cycle supply chain, and a dated changelog. No tool keeps its own separate copy of a fact, which is what stops the trackers disagreeing with each other.
As of August 2026 it covers 30 reactor designs across 19 companies, the 12 reactors in the DOE pilot program, 17 sites, and 23 offtake agreements, against 61 cited sources.
Individual claims are cited to their sources throughout the tools, so any specific figure can be traced back to the filing, announcement, or report it came from.
Most of the editorial judgment in this project lives in inclusion rules. They exist because the easiest way to make a nuclear tracker look impressive is to count everything anyone has ever announced. These rules deliberately do not.
A deal enters the order book when there is a specific, named customer and a size. That standard is met even when the agreement is non-binding — a named megawatt figure with a real counterparty is a fact about the market, whether or not money has changed hands.
What is excluded is the company-reported aggregate: "over 80 units across Europe", a multi-gigawatt "LOI pipeline" spread across unnamed parties, umbrella options with no identified buyer. These are self-reported totals across counterparties nobody can check.
The consequence, stated plainly: this order book is materially smaller than the sum of what the industry claims. If every announced aggregate were counted, the headline figure would be roughly double. That gap is the point of the tool, not a gap in it.
Deals carry a commitment level — binding, non-binding, or none — because that distinction cannot be inferred from megawatts and is routinely lost in press coverage. A non-binding agreement is not permitted to carry a contracted-megawatt figure. The order book is built so that the difference between announced and firm is impossible to miss, because that difference is most of the story.
A developer based outside the United States enters the dataset when it has made an actual NRC filing — a letter of intent, pre-application engagement, or regulatory engagement plan — not when it has announced an intention to enter the US market. The bar is applied evenly: companies at pre-application only are included on the same terms, and companies with US ambitions but no filing are not in the dataset regardless of profile.
Each site records how exactly it is known — an identified parcel, a city, a county, or only a state. Anything vaguer than a specific site is rendered as such on the map rather than being presented as a real, chosen location. Co-located facilities are treated as one site, so a national laboratory hosting seven designs reads as one place rather than seven.
Facts are cited to primary sources — regulatory filings, company announcements, and government documents — or to trade press where no primary record exists.
First-party statements outrank press coverage. A figure given directly by a company's leadership is evidence, even when no article repeats it, and even when there is no URL to link. An empty source field is not the same thing as an unsourced claim.
This rule exists because it was once broken here: a capacity figure stated by a chief executive was deleted during a cleanup as "unsourced", which made the dataset less accurate rather than more. It was restored, and the rule was written down.
Milestone dates for the 12 pilot-program reactors are owned by the pilot dataset, which descends from the original tracker and is corrected against DOE and NRC updates. Where the broader design dataset disagrees, the pilot record wins.
A milestone marked approved rather than dated is not a weaker claim — it means the phase demonstrably cleared but the exact date is not established, usually inferred because a later milestone was reached. An approved marker is never upgraded to a date that cannot be sourced.
Material changes are recorded in a dated changelog, surfaced on the home page and covering events from August 2025 onward. The dataset is revised as milestones are reached, deals are announced, and errors are found.
Corrections are welcome and will be acted on. If something here is wrong — a date, a megawatt figure, a status, an attribution — please say so, ideally with a source. Corrections from people working in the industry are the single most valuable input this project receives.
Quoting a figure, linking to a tool, or citing this work in journalism, research, or commentary is welcome and encouraged — with attribution to The Second Atomic Age and a link to the specific tool. Because these are living datasets, please cite the access date alongside any figure.
| Element | Suggested form |
|---|---|
| Author | The Second Atomic Age |
| Title | The name of the specific tracker or tool |
| URL | The tool's own address, e.g. thesecondatomicage.com/order-book/ |
| Accessed | The date you retrieved the figure |
The trackers, their underlying dataset, the written analysis, the visual design, and the generated graphics are the original work of this project and are not offered for republication or redistribution. Specifically, without prior written permission:
None of this restricts ordinary reference: quoting a figure with credit, linking to a page, or discussing what the trackers show is exactly what this project is for. If you want to do something beyond that — a partnership, a licensed dataset, a republished chart — get in touch and the answer is often yes.
© 2026 The Second Atomic Age. All rights reserved.