The B1 unit was taken offline in February for an upgrade that was commissioned to Alstom.
"We expect the unit to be synchronized with the grid during the afternoon hours but this will depend on the analysis that Alstom is currently running, based on the data its engineers collected last night," Novica Antic told SeeNews over the phone.
The restart of the B1 unit is almost one month behind schedule due to bad weather conditions, which were preventing the workers from accessing the electrostatic filter and the outer elements of the plant, Antic said.
The TE-KO Kostolac complex, comprising the Kostolac A and B power stations, has a total installed power generation capacity of around 1,000 MW.