VVER-1200 Reactor Technology

The Russian-designed NPP chosen by the Republic of Kazakhstan for construction consists of two VVER-1200 reactor units with a total capacity of 2,400 MW. This design has been developed in full compliance with the recommendations of the International Atomic Energy Agency (IAEA) and the safety standards set by the EUR Association and the Association of Western European Nuclear Regulatory Authorities (WENRA). VVER-1200 belongs to the generation 3+, which means that it meets higher safety standards than previous generations and has improved technical and economic performance.

VVERs are pressurized water reactors that use light water as both coolant and moderator. These reactors are considered to be some of the most reliable and safest in the world. They have proven their effectiveness through successful trouble-free operation for more than 1,400 reactor-years.

The guaranteed life cycle of a Russian-designed NPP with GEN 3+ VVERs is 60 years with possible extension up to 80 years, which means that during this period, local suppliers are involved in the construction, supply of equipment, maintenance, service support, and modernization of the NPP in collaboration with Russian specialists.

Based on the international experience in building Russian NPPs, every dollar invested in a Russian-designed NPP with two VVER-1200 reactors and a 20-30% localization level is estimated to bring $1.9 in revenue for local suppliers, $4.3 in GDP for the country, and $1.4 in tax revenues for the national budget. The combined active and passive safety systems of the modern GEN 3+ NPPs ensure their safety and provide a strong defense in deptheven without operator intervention. The passive systems require no power supply. Therefore, active and passive systems work together combining the speed and controllability of active systems with the capability to operate without power supply of the passive systems.

The safety system uses four barriers that confine radioactive materials and prevent them from entering the environment. The first barrier is the fuel matrix, which prevents fission products from escaping under the fuel element's cladding. The cladding is the second barrier that prevents fission products from entering the coolant in the main circulation circuit. The third barrier is the the primary circuit, which prevents fission products from escaping into the containment. Finally, the fourth barrier is a containment system that prevents the release of fission products into the environment. Each barrier's integrity is ensured with corresponding safety systems, both active and passive.

A significant achievement in the development of safety systems for Russian NPPs is a core catcher. This is a metal structure filled with special cassettes containing so-called "sacrificial material". In the event of a hypothetical accident involving nuclear fuel melting, the core catcher ensures that the corium is cooled and solidified. It also confines radioactive gases and aerosols. The fuel and reactor components are kept in conditions that prevent any further nuclear chain reactions from occurring..

The outer containment of the NPP is designed to withstand various external impacts, both natural and man-made, including aircraft crashes, earthquakes up to magnitude 8, tornadoes, and windstorms with speeds of up to 56 meters per second.. These include plane crashes, earthquakes measuring up to 8 points, tornadoes, and wind storms with speeds up to 56 meters per second.