State news agency Belta and Russian sate nuclear corporation Rosatom said the 1,110-MW unit is operating at nominal output capacity.
The Generation III VVER V-491 plant was supplied by Russia and is the first plant of its type to begin operation outside Russia.
Since it was connected to the power grid on 3 November 2020 it has generated nearly 3 billion kWh of electricity.
Rosatom said a commission in Belarus had signed documents authorising the formal transfer of the plant from the general contractor, Rosatom subsidiary Atomstroyexport, to the owner-operator Republican Unitary Enterprise Belarusian Nuclear Power Plant (Belarusian NPP).
Atomstroyexport remains responsible for operations of unit equipment during the plant’s warranty period, Rosatom said, without giving details.
"Handing over to our Belarusian colleagues the symbolic key for the country’s first nuclear power unit, I can say with full confidence that Belarus has become the owner of the most modern and safest facility,” ASE president Alexander Lokshin said.
There are two 1,110-MW VVER-1200 reactor units at the Belarusian site near the town of Ostrovets, close to the border with Lithuania.
Construction of Belarusian-1 began in November 2013 and of the identical Belarusian-2 in April 2014. Rosatom is the general contractor for both plants under a 2011 intergovernmental agreement.
The cost of the two units, largely funded by a loan from Russia, has been reported as $11bn (€9bn).
Upon completion, the two-unit station is expected to meet about 40% of Belarusian demand for electricity.
Baltic States and EU members Estonia, Latvia and Lithuania have expressed concerns, as has the EU itself, about safety at the Belarusian nuclear power station. Russia’s state nuclear corporation, Rosatom, which is building the facility, has rejected claims the facility is unsafe, saying the design conforms to the highest international standards and has passes EU-level stress tests.
The European commission has said it is “regrettable” that Belarus decided to start commercial operation of the plant without addressing all the safety recommendations contained in the EU’s 2018 peer review of Belarus’s stress test report.
