One of Budapest’s oldest power plants, Kelenföld, is not only a producer of electricity but also one of the city’s largest district heating providers, with its equipment maintained outside the heating season. This year, its 50 MW steam turbine is undergoing major maintenance to prepare it for the next 8–10 years of operation. For the refurbishment work between May 1 and October 31, the nearly 55-ton, 8-meter-long giant machine was dismantled, and some of its parts were sent to mechanical engineering plants in Poland and the Czech Republic for renovation. The generator rotor was transported to Lubliniec, Poland, on June 18.
Such a complex task requires two years of preparation, and about 20 contractors joined the plant’s specialists. Since their invention, the design and operating mechanisms of steam turbines have significantly improved in terms of efficiency and cost-effectiveness, with operational and maintenance experience leading to substantial improvements in the quality and performance of turbine components. According to Ferenc Bálint, Director of the Kelenföld Power Plant, this is one reason why comprehensive maintenance is now needed at much longer intervals—every 8–10 years in Hungary, compared to annual maintenance in the past century. Turbine performance has also greatly increased over the years; the turbine now being serviced has the same output as eight earlier turbines combined, while requiring about 80% less space.
This 50 MW Siemens condensation steam turbine with multiple extractions and highly flexible operation has been producing electricity in Kelenföld since 2006. Its operating settings can easily be adjusted, which is important for quick adaption to electricity demand.
According to Márton Kovács, Head of Maintenance, the process takes about five months because both the turbine and its generator rotor must be removed, and only foreign plants perform this type of maintenance. Therefore, the generator rotor was sent to Lubliniec, Poland, while the turbine rotor was taken to Plzeň, Czech Republic.
Zsolt Humenyik, Director of Budapest Power Plants, emphasized that their goal is to extend operating periods between maintenances and continuously reduce the risk of breakdowns. For this reason, preventive maintenance and condition monitoring are carried out to a very high standard at the plants operated by Budapest Erőmű Zrt. The high-capacity turbine will be out of service for nearly half a year, but this will not cause disruptions, as summer heat demand is traditionally met with boilers. During the heating season from October 15 to April 15, the turbine will operate at full capacity again.