An index of the advanced-nuclear buildout

The Second Atomic Age

The United States is building nuclear reactors again — dozens of advanced designs racing from paper to criticality. These are the trackers and tools that follow that buildout: who's ahead, what they're building, what it costs, and how the machines actually work.

The tools
Tracker

Race to Criticality

Advanced reactors racing to first criticality and continuous operation under the federal reactor pilot program — milestone by milestone.

Tracker

Race to Commercialization

The commercialization pipeline — which advanced-reactor designs are moving from demo to deployment, and where each company stands.

Calculator

LCOE Calculator

Levelized cost of electricity compared across reactor designs, with tunable capital, fuel, and operating inputs.

Tracker

Roadmap to Commercial Scale Demo

Going critical is not the finish line. A commercial-scale demo means six things at once — full size, full fuel, coolant moving nuclear heat, the real turbine, the whole plant, and a run long enough to count. Every machine on the way there, and what each one actually proves.

Tracker

The Janus Program

An executive order gave the military until September 2028 to run a reactor on a domestic base. Six installations against that clock — five Army posts and a Navy station with no developer chosen — and how far each has got up the Army's own permit ladder. Zero permits issued so far.

Tracker

From Criticality to Commercial Operation

The sequel to Race to Criticality. Going critical proves a core, not a power plant. Eight machines racing to a paying load, the ladder each is climbing, and which of them have taken a reactor critical before.

Tracker

Race to Fusion Power

Fusion's milestone ladder, machine by machine — first plasma, scientific breakeven, engineering breakeven, net electricity. Five machines have cleared the first rung. None has put power on a grid.

Explorer

The Factory Floor

Every gigawatt in the order book has to be built by someone. Who has a reactor production line, what it is sized for, and how that compares with demand already announced.

Reference

Company Profiles

Every developer in one place — the sequence of machines each is building and what each one proves, plus their designs, order book, and latest news.

Reference

Reactor Anatomy

The design dimensions, the common archetypes, and which current reactors fit each — the companion to the Reactor Anatomy series.

Reference

Reactor Profiles

Every reactor in the tracker as one spec table — design and operated power, fuel enrichment, form and geometry, coolant, moderator, spectrum and power density. The specific counterpart to Reactor Anatomy: archetypes there, actual machines here.

Explorer

The Design Space

A shifting venn of the advanced-reactor field — regroup every design by size, fuel, moderator, coolant, target industry, and more, and see where they overlap.

Explorer

Paper to Power

Every advanced-reactor design on one clock — from design approval through licensing and construction to first criticality and commercial operation.

Explorer

The Buildout

Where it's actually being built — every sited design and firm order on a US map, from the Idaho test complex to the hyperscaler campuses.

Explorer

The Order Book

The demand side — who has agreed to buy how many megawatts, and how much of the ~26 GW headline order book is actually firm versus merely announced.

Explorer

The Fuel Cycle

The whole supply chain around the reactor — the nine stages from mine to repository, and who is racing to rebuild each one, from the HALEU crunch to the waste question.