Beyond maintenance: Why power producers need to rethink turbo generator reliability

Operators can keep critical assets running longer through lifecycle management, predictive maintenance, and timely repairs.

Power producers today are facing a different operating environment than they were a decade ago. With the growing electricity demand that is fuelled by artificial intelligence (AI), data centres, and digitalisation, generators are also expected to operate more flexibly to support complex power grids. Such changing demands place greater stress on ageing assets; hence, reliability and long-term performance are more important than ever.

These challenges were the topics of discussion at the Asian Power webinar in partnership with Sulzer, titled “Seizing Opportunities & Mitigating Risks in Turbogenerator Operations.” Featuring Rajendra Nuthakki, Business Development Manager – Southeast Asia, Sulzer, and Dr Yali Natalie Feng, Chief Electrical Engineer, Sulzer, the session highlighted practical strategies on how power producers can move from reacting to failures to preventing them.

“Most failures don't come from nowhere; they simply aren't caught in time,” Nuthakki said, challenging a common misconception.

He explained that insulation failure remains one of the leading causes of unplanned generator outages. Many of these failures begin developing long before operators notice any changes in performance. But with the right inspections and diagnostics, these risks could be identified early.

A new maintenance mindset

According to Nuthakki and Dr Feng, there are two major trends that are reshaping the current power industry. First is the growing integration of renewable energy, which forces conventional generators to operate more flexibly to help stabilise electricity grids. Second is the rapid expansion of AI and data centres, which drive electricity demand to unprecedented levels.

New business opportunities are created through these trends. However, they also accelerate the deterioration of critical equipment with the repeated thermal, electrical, and mechanical stresses that can shorten insulation life, increase vibration, and speed up component fatigue.

To proactively respond to this, Nuthakki encouraged operators to adopt a lifecycle management approach. With this, there is continuous assessment of equipment health and evaluation of developing risks.

“The goal isn't to fix machines after they fail; it's to maximise reliability and availability through proactive lifecycle management,” Nuthakki said.

Dr Feng expounded on this by explaining that generator failures are rarely caused by a single issue. Instead, equipment condition is influenced by how the machine is operated, the environment it works in, maintenance history, and decisions made throughout its service life. One of the biggest challenges, she noted, is that most problems develop gradually inside the machine whilst normal operations continue.

“Our goal is to identify those problems before they turn into failures,” she stated, emphasising the importance of predictive maintenance. 

Supported by inspections, testing, condition monitoring, and diagnostics, this approach allows operators to detect issues earlier, understand their root causes, and determine whether repairs, upgrades, retrofits, or life extension projects are the best course of action.

A particular focus of the session was insulation health. Dr Feng described insulation as one of the most critical components in high-voltage generators, with partial discharge serving as an early warning sign of deterioration.

Repair before replacement

These principles are illustrated in several real-world case studies from Sulzer projects across Saudi Arabia, the United Kingdom, and Indonesia.

One involved a generator where elevated partial discharge readings and ozone odours revealed developing insulation damage before a major breakdown occurred. Early intervention enabled Sulzer's engineers to repair the affected insulation system and return the generator to service without requiring a complete rewind.

Another project demonstrated how changing operating requirements had accelerated wear in a generator originally designed for baseload operation. Sulzer used detailed diagnostics and engineering modifications to restore reliability.

Another example, and perhaps the most striking one, involved a generator that had spent years out of service. Sulzer’s comprehensive technical assessment replaced heavily corroded retaining rings with upgraded materials and repaired the insulation system. The result was an additional 11 years of service life.

“Always think about repairing first before replacing,” Nuthakki said, adding that modern diagnostics give operators a much clearer understanding of equipment condition.

Dr Feng likewise reminded operators that early action creates more options. “Don't wait for a failure before making a decision.”

Electricity systems become more dynamic, and demand continues to grow. Amidst this landscape, the webinar highlighted the important message that reliable power generation is now about understanding asset conditions, making informed decisions, and taking action before small problems become major outages.

Dive deeper into the conversation and watch the webinar to learn more about turbo generator reliability, predictive maintenance, and lifecycle management strategies.

Missed the webinar? Catch the full Sulzer webinar video on-demand here.