Seasonal grid instability challenges in Pakistan—II

Pakistan’s generation capacity, encompassing northern hydel, southern nuclear, and coal sources, requires strategic solar plant installations at the DISCOs’ 132kV level. This should be facilitated by allowing power-wheeling through B2B contracts at a Use of System/Wheeling Charge of 1 US cent/kWh that allows for competitive end-use prices.

These installations are intended to serve local loads, reducing daytime transformer load and transmission losses on both the 500/220kV and 220/132kV networks. To prevent evacuation constraints, it is essential to distribute solar power evenly across the nation.

Seasonal grid instability challenges in Pakistan–I

Such equitable deployment can reduce transmission investment by aligning with lower integration costs, optimize the grid, and limit curtailments in oversized solar PV plants. Furthermore, Pakistani industries need to invest in solar PV installations to comply with international regulations on carbon emissions like the EU’s Carbon Border Adjustment Mechanism (CBAM), which is vital for maintaining competitiveness in global markets.

1. Inadequate Reactive Power Support and Voltage instability

In very long transmission lines, increased capacitance amplifies voltage, leading to network instability. This instability, particularly the Ferranti effect in long, lightly loaded lines, occurs when line capacitance surpasses inductive reactance, especially in grids with distant generation and load centers.

Electric tripping in these networks can trigger cascading failures, causing voltage or frequency fluctuations. Such stress may result in chain reaction of failures from an initial fault, further destabilizing the system and potentially causing brownouts and blackouts.

The bulk network’s insufficient number of reactors fails to maintain network voltages within acceptable limits, causing significant over-voltage issues in winter. To address this, the system operator frequently has to deactivate numerous lines, thereby reducing transmission capacity reserves essential for handling contingencies,.

Given the network’s complex operational conditions, there is a need for dynamic reactive power support such as Static Var Compensator (SVCs), STATCOMs and Synchronous Condensers at various points, which is presently lacking.

1. Inadequate Grid Monitoring and Technology available for the System Operator

The system operator faces significant challenges in grid monitoring due to outdated data acquisition systems and inadequate investment in grid infrastructure modernization. This results in a lack of real-time grid information, with over 60% of the network not being monitored in real-time and relying on outdated communication methods like fax and phone.

The incomplete implementation of the SCADA system at the National Transmission and Despatch Company (NTDC) covers only about 20% of the Grid further impacts operational control and grid management. This, along with outdated operational procedures, poses challenges in handling increased load capacity and ensuring grid stability. The situation highlights the critical need for timely upgrades and modernization of Pakistan’s grid infrastructure to enhance grid management and decision-making capabilities.

1. Policy and Market Dynamics

The rapid expansion of installed capacity in Pakistan’s power sector is largely attributable to the Government’s investor-friendly initiatives for Independent Power Producers (IPPs). These initiatives offer sovereign guarantees for power purchase agreements, ensuring high and guaranteed returns.

This approach significantly lowered investment risks, leading to a surge in investments in power generation and a swift increase in generation capacity. However, this growth in capacity quickly surpassed both the actual electricity demand and the development of the Transmission & Distribution (T&D) network, resulting in both excess capacity on the supply-side as well as unmet demand.

This situation highlights the challenges in balancing aggressive capacity expansion with demand dynamics and emphasizes the need for more demand-driven approaches in power-sector planning and development.

The energy and power sector’s sensitivity to pricing dynamics highlights the need for policies that are not only market-based, transparent, and stable, but can also adapt to evolving market conditions, technological advancements and grid modernization.

Such policies should encourage investments in infrastructure modernization and renewable energy sources, thus promoting environmental sustainability and energy security. Moreover, regulatory frameworks must be agile, effectively accommodating the rapid changes in energy consumption patterns and the growing demand for electricity. Generation focused policies with fixed returns that monopolize profit and socialize risk, should instead have been market based.

Emphasizing energy efficiency and demand-side management is crucial for mitigating technical and operational challenges in the energy sector. It is important to note that during winter months in Pakistan, gas consumption in residential sectors, particularly among middle- and high-income households, increases significantly.

These households experience an increase of over 400% and 700%, respectively, for water and space heating requirements. To address this, a shift in space heating from gas to electricity using heat pumps—devices that transfer heat from cooler spaces to warmer spaces—is required.

In Pakistan, where domestic power demand constitutes over half of the total and shows high sensitivity to weather variations, effective Demand Side Management (DSM) is imperative. Key DSM strategies include the implementation of Advanced Metering Infrastructure for improved monitoring, Demand Response Techniques to adjust usage during peak times, and a focus on efficiency and conservation through passive solar designs and enhanced insulation.

1. Economic Dispatch vs Grid Reliability

The first priority of the System Operator, i.e., National Power Control Center (NPCC), is ensuring system reliability and safety to maintain voltage and frequency limits and prevent overloading. This is crucial to avoid brownouts and blackouts. Subsequently, considerations such as fuel constraints, hydro resources, and policies are taken into account, followed by economic dispatch according to merit order.

The challenge arises from the uneven geographical distribution of cost-effective and reliable power generation resources across the network necessitates Security-constrained Economic Dispatch. However, these issues often result in extensive debates between the System Operator and the National Electric Power Regulatory Authority (NEPRA) during hearings on economic dispatch.

Frequently, plants are dispatched out of merit order to support local voltage and grid reliability, while more economical resources are curtailed to maintain operational reserves. Under significant pressure to implement economic dispatch, the System Operator is often compelled to make compromises on grid reliability to minimize financial losses.

1. HR Capacity Constraint of the System Operator

• The System Operator’s workforce issues extend beyond high turnover and slow hiring. It also struggles with inadequate training programs, leading to a skills gap in critical areas like system security and advanced technology.

Additionally, budgetary constraints limit the ability to offer competitive salaries, further complicating recruitment and retention efforts. The lack of a robust succession planning and staff development strategy exacerbates these challenges, risking long-term operational efficiency and system reliability.

Conclusion

The combination of these factors - seasonal variability in power generation, maintenance challenges, industrial grid connectivity issues, a capacity trap, power system management complexities, infrastructure investment gaps, policy and market dynamics, along with geographical and technical constraints - collectively increase the likelihood of blackout winters in Pakistan.

To effectively prevent brownouts and blackouts requires a comprehensive approach that encompasses regular maintenance and upgrading of power infrastructure, including plants and transmission lines. Enhancing grid management with advanced monitoring systems, diversifying energy sources with a blend of renewable and traditional options, and implementing dynamic load management are keys.

Additionally, strengthening the training of system operators, investing in modernizing grid infrastructure, updating policy frameworks, and developing emergency response plans are essential. These efforts, combined with improved grid monitoring and balancing economic dispatch with grid reliability, will contribute significantly to the reliability and stability of the power sector.

Copyright Business Recorder, 2024