International Experts Begin Pre-Startup Review of Akkuyu NPP Unit 1
Experts from the Moscow Centre of the World Association of Nuclear Operators (WANO) have begun a pre-startup peer review of Akkuyu Nuclear Power Plant’s first unit in Türkiye.
The experts are assessing whether personnel are prepared to operate the VVER-1200 reactor unit under both normal and abnormal conditions. The review is one of the final stages in preparing the plant for first criticality and power start-up.
Digital Twin and Full-Scope Simulator
A Russian hardware-software complex plays a key role in training the Turkish nuclear plant operators. The full-scope control room simulator effectively serves as a digital twin of the first power unit. It models the operation of all reactor and turbine systems with high accuracy and in real time.
The virtual replica of the power unit accounts for physical processes in the reactor core, the hydrodynamics of the primary and secondary circuits, turbine-generator operation and the performance of auxiliary equipment. As a result, operators can practice procedures on a precise digital replica of the actual facility. The simulator software was developed by Russian professionals and integrated with the personnel knowledge assessment system.
The simulator reproduces the ergonomics of the actual unit control room. Instructors can simulate an equipment failure, a change in coolant parameters or an emergency protection actuation at any time. This allows the most challenging scenarios to be studied safely, without exposing expensive operating equipment to risk.
Review Scenarios and Personnel Assessment
As part of the pre-startup review, WANO experts are observing plant personnel as they work through several normal and emergency scenarios. Operators practice transitions between power levels, scheduled switching operations in the electrical supply systems and responses to a loss of off-site power.
Particular attention is being paid to personnel responses to simulated failures of safety-significant equipment. The scenarios cover a wide range of abnormal conditions, including failures of main circulation pumps, disruptions in cooling systems and control-system malfunctions. Experts assess how quickly decisions are made, whether operators select the correct action algorithms and how effectively the shift team works together.
The review also assesses safety culture. Experts examine team communication, compliance with procedures and the use of technical documentation. Any deviations are recorded for subsequent review and for adjustments to training programs.
Instructors from Rosatom Technical Academy have provided thousands of hours of training to Turkish personnel. The theoretical training was conducted in Russia, while practical skills were developed at Russian reference plants equipped with VVER-1200 reactors. The personnel are now applying those competencies at the Akkuyu site under the supervision of international experts.
Russian APCS for Plant Operation
Akkuyu Unit 1 is equipped with a Russian automated process control system (APCS). It provides centralized monitoring of thousands of equipment parameters and controls all systems of the power unit. The system collects telemetry from field sensors and transmits the data to the unit control room in real time.
The APCS architecture was designed to meet stringent cybersecurity and reliability requirements. Control segments serving safety-significant equipment are isolated from corporate networks and use redundant communications channels.
The system automatically performs reactor protection functions when parameters move beyond permissible limits. This reduces the impact of human factors and improves the reliability of power-unit control under all operating conditions.
Integrating the APCS with the full-scope simulator makes it possible to synchronize training with the actual control system. The digital environment thus becomes a common platform for training, assessment and subsequent plant operation.
Peer Review and Commissioning
A WANO pre-startup peer review is an international practice for assessing a plant’s readiness for safe operation. The expert team includes representatives from nuclear power plants in different countries, including professionals from the association’s Moscow Centre.
The review is conducted several months before nuclear fuel is loaded into the reactor. Its findings are compiled in a report with recommendations that are taken into account before start-up.
Akkuyu Nuclear Power Plant is being built in Türkiye’s Mersin Province and will be the country’s first nuclear power plant. The project comprises four VVER-1200 Generation III+ power units with a combined capacity of 4,800 MW. Nuclear fuel was delivered to the first unit in spring 2025, after which staged start-up operations began.
Successfully completing the peer review will confirm that the Turkish operators are ready to operate the power unit independently. The Akkuyu experience will serve as a foundation for developing Türkiye’s national nuclear power sector and training personnel to operate future power units.
