The VVER-1200 is a Generation III+ pressurised water reactor developed by Rosatom, Russia's state atomic energy corporation, with roughly 1,200 MWe of electrical and 3,200 MWt of thermal output. An evolution of the VVER-1000, the design is built for a 60-year operating life, with passive safety systems, a core catcher and a double-walled containment.
How does the VVER-1200 work?
VVER is the abbreviation of the Russian term for "water-cooled, water-moderated power reactor". In Western terminology it belongs to the pressurised water reactor (PWR) family. Fuel assemblies in the core heat the water in the primary circuit; because the water is kept at a pressure of about 16 MPa, it does not boil. The hot water flows through four cooling loops to horizontal steam generators, where it turns the water of the secondary circuit into steam. This steam drives the turbine, and the turbine drives the generator. The primary-circuit water and the steam going to the turbine never mix.
The pressuriser maintains the pressure in the primary circuit, while four main circulation pumps keep the water moving. This group of equipment inside the reactor building is called the nuclear island; the section housing the turbine and generator is called the conventional island.
Which features make it Generation III+?
- Core catcher: A structure beneath the reactor vessel that collects and cools a molten core in a severe accident. Details are in the core catcher entry.
- Passive heat removal: Systems that remove residual heat by natural circulation, without electricity or operator action.
- Double-walled containment: The inner shell is designed for internal pressure, the outer shell for external impacts such as an aircraft crash.
- Long service life: The main equipment is designed for 60 years of operation.
Main components and their logistics dimensions
| Component | Quantity per unit | Logistics perspective |
|---|---|---|
| Reactor pressure vessel | 1 | At Akkuyu 330–350 tonnes, approx. 11.5–12 m |
| Steam generator | 4 | 340–355 tonnes each, 14–15 m long, approx. 4 m in diameter |
| Main circulation pump | 4 | Heavy equipment; casing and motor can be shipped separately |
| Pressuriser | 1 | Long, narrow cylindrical vessel |
| Core catcher | 1 | Body and filler sections arrive piece by piece |
| Fuel assembly | 163 | Fresh fuel is transported under the radioactive materials regime |
Transport of the vessel is covered in the reactor pressure vessel entry, and the crane used to install it in the building in the polar crane entry.
Which power plants use the VVER-1200?
- Russia: The first unit, Novovoronezh II-1, was connected to the grid in August 2016 and entered commercial operation in February 2017. The same design is used at the Leningrad II units.
- Belarus: Two units of the Ostrovets (Belarus) plant.
- Bangladesh: Two units of the Rooppur plant.
- Türkiye: Four units of Akkuyu NPP.
- Egypt: Four units of the El Dabaa plant.
- Hungary and China: Paks II, and new units at Tianwan and Xudabao.
How does the design affect logistics?
A standardised design means that equipment dimensions and packing specifications largely repeat from project to project. Most of Akkuyu's reactor vessels and steam generators were brought from the Atommash plant in Volgodonsk directly to the plant's jetty after a sea voyage of about 3,000 km. A logistics planner can apply the transport solutions developed for Akkuyu in a similar way at El Dabaa or Rooppur. On the other hand, since most of the equipment is manufactured in Russia to Russian nuclear standards, the document set, equipment passports and KKS coding are an integral part of each shipment. The logistics of smaller-scale designs are compared in the SMR entry.
How does Voltim Global support this?
The more than 450 shipments Voltim Global has made from Russia to Akkuyu since March 2024 cover the flow of auxiliary equipment and materials to a VVER-1200 construction site. In nuclear project transport, these loads are carried mainly via the Tuapse–Taşucu Ro-Ro line and by road when needed.