Construction workers at the Akkuyu nuclear power station being built by Russia’s state nuclear corporation in Turkey have completed the concreting of the dome of the outer containment shell of the Unit 1 reactor building.

Two tower cranes, six concrete distribution booms and 34 concrete mixer trucks were used in the work, Rosatom said.

The work was carried out in four stages and took 104 days using 3,511 cubic meters of high-strength self-compacting concrete mixture.

The concreting follows installation of the top section of the dome in September and means contractor Rosatom can now prepare for installation of the passive heat removal system, a safety feature which, in the event of a loss of onsite power supply, provides long-term heat removal from the reactor core to the atmosphere using natural circulation.

Rosatom is supplying four of its Generation III+ VVER-1200 pressurise water reactor units for Turkey’s first nuclear power station, on the country’s southern Mediterranean coast.

Construction of Akkuyu-1 began in April 2018. The unit was originally scheduled to be online in 2023, but latest projections have this is now likely to be 2025. A further unit at the site is expected to start every year afterwards.

Rosatom signed agreements with Turkey to build the Akkuyu units in 2010 and 2013. The cost of the station has been reported at $20bn (€18.7bn).