The information in this data visualization is based on the World Nuclear Industry Status Report (WNISR) Database, a Mycle Schneider Consulting Project, updated to 1 January 2017. Additional updates will be made as needed. The database covers commercial nuclear power reactors for which construction has or had started and does not include “planned” or “projected” power reactors. It also excludes research, heating or military reactors that do or did not generate power.
The Worldwide Nuclear Power Reactor Construction Data Visualization is based on the WNISR Nuclear Reactor Database. Historic data are often drawn from the International Atomic Energy Agency's (IAEA) Power Reactor Information System (PRIS), from the World Nuclear Association's (WNA) online database, and from WNISR’s own research. The annual WNISR provides hundreds of bibliographical references, all of which are available on the WNISR website.
Information on reactor characteristics (type, model, capacity, provider, operator) are mainly drawn from IAEA-PRIS. Provider groupings by country or international consortia have been established by WNISR.
The main discrepancies between IAEA and WNISR data relating to reactor constructions:
• IAEA data depends on information provided by Member States; WNISR research attempts to establish which construction projects can be considered "active." If several credible sources—either in the open literature or from the WNISR's international network of contacts—corroborate a given status, a project will be either added to or withdrawn from the IAEA's list of reactors "under construction."
• The IAEA sometimes creates "new" construction-start dates, when there has been a significant interruption in the building of a nuclear power plant. WNISR tries to document these interruptions, but does not modify the original construction start date.
• Construction data in IAEA-PRIS have not only changed over the years for some reactors; some reactors have simply disappeared from the system. Not all of those changes are reflected in the WNISR database.
The date of a construction start is considered to be the moment the concrete base slab of the reactor building is being poured. Site preparation and excavation work are not included. For floating reactors (Russia and China), as no concrete is being poured, WNISR uses the “keel laying ceremony” of the barge as the construction start date.
Over the years, in many cases reactor construction has been suspended or abandoned. Suspension and cancellation apply only to “construction” and not to “projected” or “planned” reactors. Reactors enter the WNISR statistical database only when construction has started.
• Temporary Suspension
A reactor construction project that was once suspended but has resumed.
• Indefinite Suspension
A construction declared “suspended”—by the operator, authorities, regulators, etc., or listed as “suspended” in the IAEA-PRIS—that has not resumed as of January 1, 2017, and has no date or real prospect of restart. This includes non-official suspensions, for which WNISR has determined that there is de facto no active construction and no prospect of timely restart.
• Abandoned Construction
A construction declared cancelled, by the operator, authorities, regulators, etc. or through any other official decision, or listed as “cancelled” in IAEA-PRIS. Some cancellations have been listed in the IAEA publication series “Nuclear Power Reactors in the World,” that are not yet included in the WNISR database. This includes non-official abandonments, for which WNISR has determined that there is de facto no active construction and no prospect of restart.
The WNISR definition of reactor startup is its grid connection. In the case of reactor construction, the expected startup date is not always expressed in terms of grid connection, but often as "commissioning," “completion,” “commercial operation,” or other, similar terminology. Expected startup is not always connected to a precise date; rather, it can be general, as in "early 2017," or "second semester 2018." WNISR uses “best estimates,” based on a variety of sources, when providing expected startup dates.
The total construction time is the entire length of a reactor's construction period, from construction start until it is (or is expected to be) connected to the grid or its construction is abandoned (canceled or indefinitely suspended). Temporary suspension periods are included in the total construction time.
The “Current Status” of reactors is given as of the latest update of the data visualization. The status is currently as of January 1, 2017.
The status of a reactor is “Under Construction as of January 1, 2017” when:
Construction has started before January 1, 2017;
The reactor was not connected to the grid as of January 1, 2017;
Construction of the reactor was not cancelled or suspended as of January 1, 2017.
The number of reactors “Under Construction” by year refers to the total number of reactors that met the “Under Construction” criteria as of December 31 of the respective year:
Construction of the reactor started before or during the year;
The reactor was not connected to the grid as of December 31 of the year;
Construction of the reactor was not cancelled or suspended as of December 31 of the year;
In case of suspension, construction resumed before or during the year.
“Delayed Startup” applies to reactors under construction, for which the expected startup is later than the expected startup date at construction start.
A reactor is considered Abandoned (Cancelled or Indefinitely Suspended) as of January 1, 2017 when:
Construction started before January 1, 2017;
The reactor has been declared Cancelled or Suspended (by IAEA-PRIS, operator, builder, authorities, or other knowledgeable sources) before January 1, 2017 and construction has not resumed, or
Construction is de facto suspended and no active construction is underway on site with no further prospect of restart, as of January 1, 2017.
Cancelled Constructions and Indefinite (not resumed) Suspensions are grouped under the term “Abandoned” constructions.
Completed Construction applies to all reactors that have reached grid connection, i.e., they are actually operating, in long-term outage (LTO), or in shutdown
In Operation (or Operating)
A reactor is considered in operation:
From the date of grid connection to the date of the latest power production/final disconnection from the grid;
From the date of grid connection to the date of entering LTO status.
A reactor can be retroactively withdrawn from “In Operation” status from the day it was disconnected from the grid (either to enter the LTO status or to be considered as in permanent shutdown).
In Long-Term Outage (or LTO)
A nuclear reactor is considered in long-Term outage or LTO:
When it has not generated any electricity in the previous calendar year and in the first six months of the considered calendar year;
When a reactor meets these criteria, it is retroactively withdrawn from “in operation” status and enters the LTO from the day it was disconnected from the grid.
A nuclear reactor is considered as in permanent shutdown:
From the day of latest power production/final disconnection from the grid;
A reactor can be retroactively considered in permanent shutdown if it is not restarted after an outage (LTO or other).
Nuclear Steam Supply System (NSSS):
The NSSS consists of a nuclear reactor and all of the components necessary to produce high
pressure steam, which is used to turn the turbine for the electrical generator (IAEA-PRIS Manual). The NSSS is also called the nuclear island.
The indicated nuclear provider is mainly based on the Nuclear Steam Supply System (NSSS) provider, as in IAEA-PRIS as of December 2016. In some cases, the nuclear provider has changed during construction. The WNISR database does not yet account for all of these changes.
WNISR generally uses the net electricity generating capacity as in IAEA-PRIS.
For the construction data visualisation, it refers to the design net capacity.
This interactive visualization was built for The Bulletin of the Atomic Scientists by the core team of the World Nuclear Industry Status Report (WNISR) (data & analysis) and Visionscarto.net (design & programming). We are grateful for assistance and funding provided by The Bulletin and the Pulitzer Center on Crisis Reporting.
For any question, remarks or corrections regarding the content of this visualization, please get in touch with contact@worldnuclearreport; for all technical issues please inquire with firstname.lastname@example.org.