Old Jamshoro grid station infrastructure faces operational challenges

ISLAMABAD: The Jamshoro grid station, a pivotal component of Pakistan’s power network, confronts a range of obstacles jeopardising its operational efficiency and dependability.

The System Need Assessment report, commissioned at the direction of Nepra (National Electric Power Regulatory Authority) in July 2023, was submitted by the National Power Control Center (NPCC). The NPCC is part of the National Transmission and Dispatch Company (NTDC) and serves as the Power System Operator.

The report noted that despite its critical role in the power grid, the Jamshoro grid station faces significant congestion issues due to limited incoming and outgoing transmission capacity. This congestion affects the power flow on key circuits, leading to operational challenges, especially during periods of low Available Transfer Capacity (ATC).

Besides, the operator also said that ageing infrastructure also raises concerns. This is a pressing concern that revolves around the ageing infrastructure at the station. Several crucial components, including transformers, the 220kV yard, shunt reactors and 500kv circuits, have been in service since the 1980s. This ageing infrastructure not only poses operational risks but also impacts the station’s overall reliability.

The station is further challenged by understaffing. Despite being sanctioned for 37 operations staff and 33 maintenance staff, the actual deployment falls significantly short, with only 20 operations staff and 13 maintenance staff.

The operator has recommended that the system needs a new 500kV grid station in the south. It will alleviate congestion and will enhance reliability and de-risk Jamshoro by interconnecting with existing 500kV transmission lines. The NGS would connect to existing lines, accommodate wind farms, supply KE, and ensure Thar Coal service with N-1 compliance. Expanding AC transmission lines is deemed vital for enhancing system security and preventing economic merit order (EMO) violations. Proposed options include the construction of circuits to Shikarpur or Rahim Yar Khan via Moro. To mitigate commutation failures and voltage stability issues, authorities are considering the installation of dynamic reactive compensation devices, such as STATCOMs. These measures can significantly improve voltage control and system stability. The Jamshoro grid station serves as the exclusive transit point for multiple essential functions. It facilitates the transmission of cost-effective power from K2, K3, China Power Hub, and Hubco to meet the burgeoning energy demands in the northern regions. Moreover, it acts as one of the two transit points for power plants like Port Qasim, Lucky, and Thar coal using the AC Corridor after maximising HVDC Available Transfer Capacity (ATC). This ensures a smooth flow of electricity even in peak demand periods. The station is also the sole transit point for the evacuation of wind power from Jhimpir/Gharo, following a transformation from 220kV to 500kV. Additionally, it functions as the primary common delivery point (CDP) for supplying power to Hesco and serves as one of the two CDPs for KE within the national grid, supporting up to 350 MWs at 220kV via Jhimpir-2 to KDA.