Bulgaria's sole nuclear power plant (NPP) Kozloduy has completed the planned annual maintenance of its 1,000 MW Unit 6, the power plant announced on Monday. Unit 6 was reconnected to the grid at 10:48 local time, Kozloduy NPP said in a press release. During the outage, the reactor of Unit 6 was reloaded with fresh nuclear fuel and the prescribed maintenance works were carried out. Kozloduy's other 1,000 MW unit, Unit 5, is operating at full power. The planned annual maintenance of Unit 5 was completed in May. Bulgaria's energy ministry said in July it has completed works on the project for extending the lifespan of Unit 6. Kozloduy NPP remained with two operational units - Units 5 and 6, after the plant's four other units, of 440 MW each, were closed down prior to Bulgaria's accession to the European Union in 2007 in order to address nuclear safety concerns of the European Commission.