Transmission bottlenecks

It’s a well-established fact that the power grid supply is higher than the demand in Pakistan, and that is ballooning the capacity charge per unit, and to address the issue demand must be enhanced. One reason for the low demand is growing cost while the other less debated issue is transmission constraints which restrict the full utilization of the power generation capacity. The gap exists due to lack of coordinated planning and inadequate investment in upgradation of transmission networks.

And if there is meaningful investment in the transmission network, somehow it is not optimally utilized. For example, the introduction of High Voltage Direct Current (HVDC) Matiari-Lahore transmission line has added to the system’s capacity, allowing it to cater to heavier loads over greater distances. However, In FY23, the average utilization of this crucial infrastructure remained at approximately 1,584 MW, which is two-fifth of its designed capacity of 4,000 MW.

In recently commissioned Thar Coal Power Plants transmission lines needed off-take energy have been delayed causing financial setbacks. Only 75 percent (1,800MW of the 2,400MW) energy from Thar power plants can be evacuated at any given time owing to transmission constraints. That is forcing us to rely on expensive energy sources in days of high demand.

Overall, during 2021-2023 the number of under-utilized power transformers increased by approximately 84 percent while the number of under-utilized transmission lines increased by 3.5 percent. This trend needs to be revered.

Then inter-connections are either absent or of substandard at some place – such as high voltage 500kV and 200kV transmission system of NTDC struggles with smooth evacuation of power from several highly efficient power plants. Technical constraints hinder the System Operator’s ability to evacuate electricity from efficient power plants. During FY23, the system constraints resulted in a loss of Rs 20 billion which is especially alarming because the cost of transmission line expansion is significantly less as compared to the losses incurred due to non-evacuation.

Another issue is that of the sub-par ability of the transmission system to withstand shocks. 46 tower collapses during FY23 in the transmission network of 500 KV and 220 kV were reported, causing disruption in the transmission system, posing a risk to human life.

The transmission lines are designed to operate within specified load limits. When these limits are exceeded, it can lead to overheating and voltage instability, disrupting flow of electricity and causing outages. In June of 2023, 88 power transformers were over-loaded (80% or above) highlighting major system constraints.

To address issues of over-heating, construction of additional transmission lines and substations, as well as the installation of advanced technologies for load management and real-time monitoring is paramount.

One recurring problem is blackouts in winters when higher power is supposed to transfer from the South to higher demand regions in the north. There have been two countrywide blackouts in the past four years, and to counter that, the government decided to shed load, in this winter.

To address all the above-mentioned issues, targeted investment is required in transmission and distribution systems. Unfortunately, some XDISCOs lack the capacity and independence to make investment plans. The one company in the private sector is doing it. KE has submitted an investment plan proposing the establishment of two 500 kV grid stations at KKI and Dhabeji while the interconnection capacity between KE and NTDC remains adequate.

NTDC has requested NGC for Rs 369 billion for the next 3 years which will allow NTDC to upgrade its network and explore smart grid technologies, energy storage solutions, and grid-interactive systems to enable smooth integration of renewable sources into the existing transmission infrastructure. However, the funds are still under approval.

Sooner these investments are made, lower the losses would be. And in the larger interest, the deregulation and privatization of XDISCOs should be expedited.