Bulgarian team takes on complex engineering of horizontal hydrogenerators at the “Plastira” hydroelectric power plant in Greece

The Bulgarian company “Central Energy Repair Base” (CERB VEM) has won a prestigious international tender issued by the Greek public energy corporation PPC (the equivalent of Bulgaria’s NEC) for the repair and modernization of the 66-year-old Plastira Hydroelectric Power Plant, BalkanEngineer.com learned from a company announcement. In a competitive bid against a major Italian engineering firm, the Bulgarian specialists were selected to carry out the rehabilitation of the facility, which generates between 220 and 300 GWh of green electricity annually.

The project involves a comprehensive overhaul of three hydroelectric generators, each with a capacity of 47 MW, and an increase in their efficiency by up to 10%. The work presents a significant engineering challenge, as the three units at the Plastira Hydroelectric Power Plant are of a rare type—horizontal machines with two turbine runners located on either side of the shaft. Contrary to standard practice, the Bulgarian team will also be fully responsible for the preliminary disassembly and removal of the heavy rotors. The actual on-site work will begin in September and will be carried out in phases through 2027. The repairs will be carried out only outside the irrigation season, as the water from the reservoir of the same name (located in a “Natura 2000” area) is of vital importance to agriculture in the Thessalian Plain.

The main CERB VEM team, led by the company’s chief engineer, will be based in Greece. “Greece follows a consistent policy of preventive maintenance, upgrading between two and four generators annually. It is encouraging that in recent years, Bulgaria’s NEC has also begun to actively focus on preventive modernization, rather than merely reacting to breakdowns,” commented Eng. Krasimir Kolev, manager of CERB VEM.

The director of the “Plastira” hydroelectric power plant is Amalia Stafila—the only woman to hold such a position in Greece. Thanks to her many years of leadership, the project has retained the power plant’s complete technical documentation. CERB, for its part, is one of the oldest companies in the Balkans specializing in the diagnostics and maintenance of large electrical machinery, with a 77-year history; since 2008, it has successfully modernized more than 10 hydroelectric power plants owned by Greece’s PPC.

Photo source: CERB VEM