The Budapest Research Reactor (BRR) is a VVR-type (water-cooled, water-moderated) Soviet design reactor. It went critical in 1959. The initial thermal power was 2 MW. The first upgrade took place in 1967 when the power was increased to 5 MW using a new type of fuel and a beryllium reflector. A full-scale reactor reconstruction and upgrade project started in 1986, and finished in December 1992. The upgraded 10 MW reactor received the operation license in November 1993. According to the Hungarian safety regulations, a periodic safety review (PSR) was conducted in 2002-2003, as a result of this the operation license was renewed in November 2003 that is now valid until further notice. After every ten years of reactor operation the periodic safety review report has to be prepared. The new one was worked out in 2012. In the frame of this project the reactor tank and the storage tank were inspected.
The conversion has been completed in 2012; the last high (36%) enrichment fuel assemblies were removed from the reactor core in November 2012.
Main technical data
Reactor type: Light-water cooled and moderated tank-type reactor with beryllium reflector
Fuel: VVR-SM(-M2) from November 2012,
190 fuel assemblies with less than 20 % 235U initial enrichment
Core geometry: Hexagonal (height: 600 mm; diameter: 1000 mm)
Equilibrium core: 190 fuel assemblies (in single equivalent)
Control: • 3 safety rods (B4C);
• 14 shim rods (B4C);
• 1 automatic (fine) rod (SS)
Nominal thermal power: 10 MW
Neutron flux density in the core: • 2.5 * 1014 n/cm2s (thermal in the flux trap)
• 1 * 1014 n/cm2s (approx. max. fast flux in the fast channel)
In December 2023, the Budapest Research Reactor was granted a further 10-year extension of operating license, however, the Hungarian Atomic Energy Authority imposed certain conditions to be met by the end of 2025. One of the major tasks is a partial reconstruction of the main building and some components of the reactor infrastructure.
Public Relations
The reactor is open for the public. Groups of visitors are welcome monthly (on the last Friday of the month). Special appointments are possible. Guided technical tours are frequently organized for the international nuclear community on the occasion of conferences and symposia held in Budapest or in the region (e.g. Vienna).