Rosatom Begins Pouring Concrete for Reactor Building of Unit 5 at Paks NPP

Tashkent, Uzbekistan (UzDaily.com) — On 5 February 2026, a ceremonial event marking the pouring of the “first concrete” into the foundation of the reactor building for Unit 5 took place at the Paks Nuclear Power Plant construction site in Hungary.

This unit is part of the latest Russian-designed nuclear project featuring a Generation III+ VVER-1200 reactor. The Engineering Division of the Russian state corporation Rosatom serves as the general contractor and project designer.

The ceremony was attended by Rafael Grossi, Director General of the International Atomic Energy Agency (IAEA), Péter Szijjártó, Hungary’s Minister of Foreign Affairs and Trade, and Alexey Likhachev, Director General of Rosatom. Paks NPP will become the first station in the European Union to operate Russian VVER-1200 reactors.

The commencement of the “first concrete” marks the formal recognition of the facility as an official “under-construction nuclear power plant” under IAEA standards.

This milestone is considered pivotal for the development of Hungary’s nuclear energy sector and underscores the long-standing peaceful nuclear cooperation between Hungary and Russia, which dates back to 1956.

In his address, Alexey Likhachev highlighted that the Paks 2 project reflects constructive and mutually beneficial relations between the two countries, continues decades of collaboration in nuclear energy, and will bring Hungary significant economic and strategic benefits. He also emphasized that the project reinforces Rosatom’s leading position in the global market and contributes to the development of Russian industry.

Hungary’s Minister of Foreign Affairs and Trade, Péter Szijjártó, noted that Paks 2 represents a strategic project for the country, ensuring long-term energy security and independence. According to him, the new plant will generate up to 70 percent of the electricity required in Hungary, reducing reliance on global energy market fluctuations.

The permit to pour the first concrete and construct the nuclear island buildings was issued by Hungary’s Atomic Energy Authority on November 4, 2025. Additional licenses confirm the project’s compliance with international, European, and national nuclear safety standards. The comprehensive safety approach includes both active and passive systems to guarantee regulatory compliance.

The quality of the concrete mix and construction work is critical to the strength and durability of the building, the integrity of structures, and the reliability of installed equipment. Pouring the foundation slab of Unit 5 will continue continuously until the end of the year, requiring approximately 9,000 tons of reinforcement and 43,000 m³ of concrete. Quality control is conducted at all construction stages.

Once the foundation is complete, work will begin on the internal and external containment structures of the reactor building, installation of floors and equipment, including the melt trap—a key component of the passive safety system.

The new units at Paks NPP are being built under the Russia–Hungary intergovernmental agreement of January 14, 2014, and three fundamental contracts for the plant’s construction. The primary license for the VVER-1200 units was issued in August 2022, after which preparatory work, including excavation for Unit 5, commenced. The project includes localization of up to 40 percent of production and involves leading Russian and Hungarian companies, as well as major international firms from Europe, Asia, and the Americas.

The VVER-1200 technology meets strict international standards and is already in use at operational and under-construction facilities in Russia, Belarus, Turkey, Bangladesh, Egypt, and other countries. The reactor’s design life is 60 years, with a possible 20-year extension.

The project provides orders for Russian enterprises. Reactor manufacturing at the AEM-Specstal plant in Saint Petersburg began in April 2024. To date, all blanks for Units 5 and 6, totaling 3,440 tons, have been completed. Reactor vessel assembly will take place on-site.

The first major equipment for Paks NPP has already been delivered, including the 730-ton melt localization device. The project involves Rosatom’s Machine-Building Division facilities in Saint Petersburg,