Rosatom completes primary circuit hydraulic tests at Akkuyu 1
Pressure in the primary circuit reached 24.5 MPa, about one-and-a-half times the reactor's normal operating pressure, with water at 135°C.
Key facts
- Hot functional tests next, four main circulation pumps at no less than 260°C
- Cold hydraulic tests began in June following the loading of dummy fuel
- Rosatom building four VVER-1200 reactors at Akkuyu under build-own-operate model
- Unit 1 targeted to supply Turkey's grid by end of 2026, per Rosatom
- Completed 4,800 MWe plant expected to meet about 10% of Turkey's electricity needs, per Rosatom
Hydraulic testing of the primary circuit at unit 1 of Turkey's Akkuyu nuclear power plant is complete, Rosatom said on October 9, 2026. Pressure in the circuit — the reactor, main circulation pumps, steam generators, the pressuriser and the main circulation pipeline connecting them — was raised to 24.5 MPa, about one-and-a-half times the reactor's normal operating pressure. Water temperature reached 135°C at the initial stage of the operation. Hot functional tests are to follow.
The circuit was filled with chemically demineralised water, and the main circulation pump units created the required pressure and temperature. An automated process control system (APCS) was put into operation for the tests, and operating personnel in the control room monitored the condition of equipment and pipelines using its data. In normal operation, demineralised water at up to 330°C and about 16 MPa circulates through the primary circuit, heating secondary circuit feedwater in the steam generators.
"The safe operation of the entire unit depends on the reliability of the primary circuit," said Alexey Likhachev, Rosatom's director general.
Cold tests began in June after dummy fuel loading
Cold hydraulic tests began in June, after dummy fuel was loaded, to confirm that components and systems important to safety are installed and ready to operate cold, to verify the leak-tightness of the primary circuit and to clean the main circulation pipes. Those tests were the first time the reactor systems operated together with the auxiliary systems. Hot functional tests will confirm equipment and systems are ready for operating conditions, including operation of the four main circulation pumps at temperatures of at least 260°C. Both sets of tests take place before nuclear fuel is loaded.
Four VVER-1200 reactors under build-own-operate model
Akkuyu is in the southern Mersin province and is Turkey's first nuclear power plant. Rosatom is building four VVER-1200 reactors under a build-own-operate model. Under the 2010 Intergovernmental Agreement between the Russian Federation and Turkey, the aim was for commissioning of the first unit within seven years of receipt of all construction permits. The unit 1 construction licence was issued in 2018 and work began that year. Nuclear fuel was delivered to the site in April 2023. The aim has been for unit 1 to begin supplying Turkey's energy system by the end of 2026. The 4,800 MWe plant is expected to meet about 10% of Turkey's electricity needs when completed. Turkey plans a second plant at Sinop and has held talks with China on a third, in the Thrace region. It aims to add 5 GWe of SMR capacity by 2050, the equivalent of at least 16 units.