Kathu Solar Park, a concentrated solar power (CSP) facility operational since 2019, recently completed a planned 30-day outage for its annual maintenance. This year’s programme centred on the detailed inspection and refurbishment of the steam turbine. Siemens Energy, the original equipment manufacturer (OEM), led the turbine inspection with the support of local contractors.

Maintenance activities

During the 30-day outage, the primary focus was a full inspection of the steam turbine, which involved dismantling the high-pressure and low-pressure turbine cylinders. The last two stages of blades on the low-pressure turbine rotor were removed to perform non-destructive testing of blade attachments, ensuring their structural integrity and operational safety.

In addition to turbine work, the maintenance team refurbished critical auxiliary systems, including electrical components and solar field infrastructure. Notable tasks included replacing isolation valves in the parabolic trough system to enhance reliability and ensure uninterrupted energy capture.

Specialised expertise and local engagement

Siemens Energy brought its technical expertise to oversee the turbine’s inspection and refurbishment. To supplement this, Kathu Solar Park contracted 39 local workers for additional manpower, covering roles from unskilled to semi-skilled positions. These contractors received rigorous safety training as part of the programme.

CSP maintenance vs solar PV

Unlike modular solar photovoltaic systems, CSP plants rely on integrated components that must work faultlessly together. Taking a single component offline necessitates a full plant shutdown. This year’s maintenance programme was particularly significant as it included major inspections and upgrades not previously required in earlier cycles such as opening turbine casings and updating control systems to bolster reliability and efficiency.

System upgrades and long-term benefits

Key upgrades during the maintenance period included software enhancements to the turbine controller and balance-of-plant control systems. These upgrades are designed to improve operational reliability and efficiency, reducing the risk of unplanned outages. While the updates may not immediately impact the plant’s environmental footprint, they ensure a more robust power generation system, supporting the facility’s long-term sustainability.

Outcome and future outlook

The maintenance programme was completed on schedule with key tasks like the turbine inspection showing no significant issues with the last-stage rotating blade attachments. Minor findings were addressed during the outage while any remaining tasks were postponed to future maintenance periods to minimise downtime.

Kathu Solar Park’s 2024 maintenance programme demonstrates the rigorous standards required to sustain CSP operations.