How this map is built
Every figure in Reactor Atlas comes from a named public source, carries a date, and can be traced from the sheet where it appears. This page sets out where each figure comes from, which source prevails when two disagree, how often it updates, and what you will not find here. When two sources disagree, both readings are kept: neither is deleted.
What Reactor Atlas shows
- Power reactors worldwide, operating, suspended, under construction, planned or shut down, with location, type, capacity, dates, owner and operator.
- Research and test reactors, and the U.S. Navy's moored training ships (converted former submarines), with thermal power, type and status.
- The fuel cycle: mining, milling, conversion, enrichment, fuel fabrication, reprocessing, heavy water, storage and uranium deposits.
- Monitoring signals: operational events — outages, returns to service, power changes, nearby earthquakes, regulatory findings — that regulators and operators publish on their own channels, ingested automatically.
- Official communiqués from operators, regulators and governments, and items from World Nuclear News, always with the original title and a link to the source.
- Email alerts, configurable by country, plant, signal type and severity.
Limits and coverage
- Reactor Atlas publishes what its sources publish, and nothing more. It produces no forecasts of generation, demand or price, and rates the safety or performance of no facility: where a signal carries an INES rating, the issuing body set it. Undeclared military installations are out of scope; dual-purpose reactors that public sources do record appear like any other unit. Signal coverage follows what each country publishes: in Russia we cover the movements the operator announces, and in India the source publishes exceptions rather than a per-unit confirmation. These limits are stated here because they change over time, and they are updated when they do.
- A research reactor's shutdown date when no source has published one: the IAEA does not report it for every case.
Sources, by layer
Each layer combines a fixed set of sources. Every plant, research-reactor and country sheet closes with the line "Data: … · updated on …", naming the sources behind those figures and the most recent of their dates.
Power reactors
| Source | License | What it contributes |
|---|---|---|
| Global Energy Monitor, Global Nuclear Power Tracker | CC BY 4.0, with modifications | August 2026 edition. Gross capacity, status, dates, owners and coordinates. |
| IAEA PRIS (RDS-2 and OPEX) | IAEA, cited with attribution and the reading date | RDS-2 and OPEX 2025 edition, cut off on 31 December 2024. Net and gross capacity, status, connection dates and load factors. |
| Wikipedia, List of commercial nuclear reactors | CC BY-SA 4.0 | Consulted on every data update. Status, net capacity and day-level dates where PRIS and GEM don't give them. |
| Wikidata / Wikimedia Commons | Wikidata CC0; Commons images, per each file's license | Coordinates, images and links. Capacity is not taken from here: units are not consistent across records. |
Research reactors
| Source | License | What it contributes |
|---|---|---|
| IAEA Research Reactor Database (RRDB) | IAEA, cited with attribution and the reading date | Type, thermal power, status and coordinates. The main source for this layer. |
| Wikipedia, List of nuclear research reactors | CC BY-SA 4.0 | Complement and cross-check for the RRDB. |
| Wikidata | CC0 | Coordinates and identifiers. |
| U.S. Navy | Public domain (U.S. government work) | Additions of moored training ships with a reactor (converted former submarines) that the RRDB doesn't list. |
Fuel cycle
| Source | License | What it contributes |
|---|---|---|
| Wikipedia | CC BY-SA 4.0 | The layer's main source by volume: name, status, capacity and product for most facilities. |
| Wikidata | CC0 | Second source by volume: identifiers and coordinates for most facilities. |
| World Nuclear Association, information library | Cited page by page | Category series — mining, conversion, enrichment, fabrication, reprocessing, uranium deposits — that contribute status and capacity for much of the layer. |
| CNEA (Argentina) | Each release belongs to its issuer; the original is linked | Argentine fuel-cycle facilities: mining, enrichment, fuel fabrication, heavy water and on-site storage. |
| SFEN (France) | Each release belongs to its issuer; the original is linked | Historic uranium mines in France. |
Countries and electricity mix
| Source | License | What it contributes |
|---|---|---|
| World Nuclear Association, country table | © World Nuclear Association — country table, cited with a link to the original page | Operable and under-construction reactors by country: country-level figures, never per reactor. |
| Ember, Yearly Electricity Data | CC BY 4.0 | Share of each source in a country's electricity generation, not primary energy. |
| Our World in Data (with Ember and the Energy Institute) | OWID CC BY 4.0; the underlying Ember and Energy Institute data keep their own terms | Long series of nuclear's share of electricity generation; it coexists with Ember's reading, not replaces it. |
Real-time signals
| Source | License | What it contributes |
|---|---|---|
| CAMMESA (Argentina's grid operator) | CAMMESA public data | Public data from the Argentine system operator: per-unit status for Atucha I, Atucha II and Embalse. |
| U.S. Nuclear Regulatory Commission | Public domain (U.S. government work) | Daily per-reactor status report and reportable event notifications. |
| KHNP (Korea Hydro & Nuclear Power) | KHNP public data | Per-unit status at Kori, Hanbit, Hanul, Wolsong and Saeul, South Korea. |
| Vattenfall | Vattenfall public data | Production and status per unit at Forsmark and Ringhals, Sweden. |
| Elexon BMRS | Elexon open data (BSC) | REMIT unavailability notices, United Kingdom. |
| IESO Ontario | IESO public reports | Generator output and capability, Canada. |
| RTE eCO2mix | ODRÉ / RTE, Licence Ouverte (Etalab) | National nuclear generation, France. |
| EDF | Public EDF content, for informational use | Production-unit updates, France. |
| IAEA News | IAEA, cited with attribution and the reading date | Events rated on the INES scale. |
| USGS | Public domain (U.S. government work) | Earthquakes of magnitude 4.5 or more within 150 km of a plant: context, not an incident. |
| JAIF (Japan Atomic Industrial Forum) | Public Japan Atomic Industrial Forum publication, for informational use | Per-unit status of Japan's 33 units, table updated once a month. |
| ONS (Operador Nacional do Sistema Elétrico, Brasil) | ONS open data, CC BY 4.0 | Actual hourly generation of Angra 1 and Angra 2, Brazil. |
| Central Electricity Authority (India) | Public National Power Portal data (Ministry of Power, India) | Daily exceptions report: units under outage or restriction. |
| Rosenergoatom | Public information from the state operator (Rosenergoatom, a Rosatom subsidiary) | Last reported movement per unit, Russia. |
| ENTSO-E Transparency Platform | ENTSO-E Transparency Platform terms of use, with attribution | Production unavailabilities reported within an hour across Belgium, Spain, the Netherlands, Finland, Czechia, Slovakia, Hungary, Slovenia, Switzerland, Bulgaria and Romania. |
Official communiqués
| Source | License | What it contributes |
|---|---|---|
| Regulators, operators and governments (19 official channels) | Each release belongs to its issuer; the original is linked | NRC and DOE (United States), CNSC and Bruce Power (Canada), CNEA, ARN and Nucleoeléctrica Argentina (Argentina), Vattenfall (Sweden), EDF (France), ČEZ (Czechia), ENSI (Switzerland), NEK Krško (Slovenia), Kozloduy NPP (Bulgaria), ONR (United Kingdom), Rosenergoatom (Russia), ENEC (United Arab Emirates), Kansai Electric (Japan), CGN and CNNC (China). |
| Fuel-cycle companies (11 official channels) | Each release belongs to its issuer; the original is linked | Cameco and NexGen Energy (Canada), Kazatomprom (Kazakhstan), Urenco, Centrus Energy, Westinghouse, Framatome, Global Laser Enrichment, Energy Fuels and Paladin Energy, and CNEA (Argentina). |
| World Nuclear News | © World Nuclear Association — title, date, feed summary and link | The site's one secondary source: title, date, link and the feed summary, always attributed to the World Nuclear Association by its full name; never as the source of a figure. |
How a value is chosen when sources disagree
When two sources give different values for the same fact, the one that carries an effective date wins over the one that doesn't, regardless of which source is generally more authoritative.
Beyond that, the authority order depends on the fact. Status and dates: an official statement from the operator or the national regulator, then IAEA PRIS, then Global Energy Monitor, then Wikipedia. Net capacity: IAEA PRIS first, then the operator, then Global Energy Monitor and Wikipedia. Research reactors: the IAEA RRDB, then the operator. Fuel-cycle facilities: the operator, then the World Nuclear Association and the IAEA, then Wikipedia. A status regression — from "operating" to "under construction", for example — needs an official source: a community source such as Wikipedia or Wikidata never regresses a status on its own.
When two readings sit at the same authority level and differ, the one published more recently wins, not the one consulted most recently.
An editorial correction from Reactor Atlas — always citing the primary source URL behind it — can outrank that order, but only to fix a data-reading error (a misread cell) or to add a fact the automated pipeline cannot see on its own yet.
No disagreement is hidden: when two sources don't match, both readings are kept with their source and date; neither is deleted or overwritten.
Capacity is shown on a net basis where IAEA PRIS, the operator or Wikipedia publish it that way; where the only available figure is the gross or announced project capacity, that is the figure shown. Gross also appears as an additional figure when the source gives both.
Definitions
- Net vs. gross capacity
- Gross capacity is what the electrical generator produces; net is what leaves the plant toward the grid, after the plant's own consumption and transformer losses are subtracted. Reactor Atlas shows net as the headline figure and gross as an additional figure when the source gives it.
- Operating vs. grid connection vs. commercial operation
- Grid connection is a new unit's first synchronization; commercial operation is the date the operator declares it in regular service, usually weeks or months later. First criticality is the reactor's start-up, weeks before grid connection, and is not the date the site shows. The in-service year uses the commercial-operation date when the source gives one; if not, first grid-connection; if that's missing too, the start-up year Global Energy Monitor publishes; and for a handful of historical units with no published date at all, an estimate based on construction start, flagged as such on the sheet.
- Operating
- It is in service and generates electricity on a regular basis, even though at a given moment it may be shut down for refueling or maintenance.
- Operation suspended
- The unit is out of service for an outage the source doesn't yet treat as final.
- Under construction
- Work has actually started: there is a first-nuclear-concrete date, or the source confirms construction is under way. An announced project is not enough on its own. IAEA PRIS criterion: it counts from the first structural concrete of the nuclear island (the reactor building) to first grid connection; site works and permits don't count, and non-power test reactors are not power units.
- Planned
- The project is announced or approved, but there is no confirmed construction-start date yet.
- Shut down
- Permanent retirement from service, with or without a published closure date.
- A research reactor's thermal power
- Most research reactors don't generate electricity, so they are measured by thermal power in kW — the rate at which the core releases energy — rather than MWe.
- Research reactor: operating
- The reactor is running under normal operation.
- Research reactor: temporary shutdown
- The reactor is halted for a shutdown the source doesn't treat as final.
- Research reactor: shut down
- The reactor has permanently stopped operating.
- Research reactor: decommissioned
- The reactor has been decommissioned: fuel removed and its systems dismantled.
- Research reactor: unknown
- No public source gives the reactor's current status.
How often it updates
- Power and research reactors
- Once a month (the monthly data sync), with an editorial review before it publishes.
- Electricity mix by country
- Once a month, in the same sync.
- Real-time signals
- Hourly sources (regulators, grid and plant operators) are checked every hour; daily sources, such as the NRC's daily report, every six hours.
- Official communiqués and World Nuclear News
- Every six hours.
- Email summary
- Weekly by default; anyone can also set up their own alerts with instant, daily or weekly frequency, by country, plant or signal type.
- The "Data: … · updated on …" line
- Shown at the foot of every plant, country or research-reactor sheet, with the most recent date among the sources actually behind what's on screen.
Corrections and contact
Every plant, research-reactor and fuel-facility sheet has a "Report a wrong value" button at the foot, opening a short form: which value is wrong and what the correct source is. Open it from the map, on any plant, research reactor or facility.
Every correction that gets incorporated is documented with the primary source URL behind it, the same as any other reading: what other sources said is never deleted or overwritten.
Data licensing and enterprise use: get in touch through fedecaccia.com.