Condition Assessment and Reliability Analysis of a Thermal Power Plant Surface Condenser

Condensers are essential for thermal power plant efficiency, ensuring effective steam condensation and maintaining low turbine back pressure within the Rankine cycle. Over time, tube degradation—caused by fouling, scaling, erosion, and corrosion—can lead to performance loss, derates, and costly outages. This study evaluates the condition and reliability of a 350 MW condenser in southern Malaysia, in service since 1993, using visual inspection, eddy current testing (ECT), and metallurgical analysis. ECT results from 2023 revealed significant wall loss concentrated in top quadrants, with 243 tubes showing measurable degradation and 334 tubes plugged to date (~2.75%). Metallurgical analysis confirmed microbially induced corrosion (MIC) as a key contributor to internal pitting. Economic modeling indicates that even minor leaks can result in substantial financial losses, reinforcing the need for proactive maintenance. Recommendations include systematic tube mapping, enhanced deposit characterization, improved cleaning protocols before ECT, and a phased retubing strategy to mitigate risk and sustain long-term condenser performance.