ISLAMABAD: The National Electric Power Regulatory Authority (NEPRA) has declared that the National Transmission & Despatch Company (NTDC) is incapable of transmitting the electric power from efficient power plants and it still requires a longer period to fix the existing constraints which are causing the operation of power plants in violation of EMO.
NEPRA, in its NTDC’s performance evaluation report 2021-22 released the other day, said over the years NTDC has been reporting constraints in transmission system as one of the major causes of under-utilization of efficient power plants.
During the reported period, at several instances, the transmission system remained incapable to transmit the electric power from efficient power plants to load centers to meet the demand, said the report, adding that NTDC needs to take measures/steps to remove constraints in its network to off-take electric power from existing power plants as well as upcoming power projects in light of the Transmission System Expansion Plan (TSEP) duly integrated with the plan for induction of new generation plants in accordance with Indicative Generation Capacity Expansion Plan (IGCEP). Similarly, the data pertaining to system constraints revealed that most of the grid stations are overloaded.
NTDC’s progress on removal of system constraints is slow and around 11 projects are delayed. NTDC needs to complete it on priority to avoid any adverse impacts on the power sector.
NTDC could not be able to complete the interconnection facilities for evacuation of power from new power plants as per the approved design and within the stipulated time period and thus caused under-utilization of the available capacity. It has also been observed that progress on evacuation projects is slow due to which cheap electricity located in Thar is compromised. Such as the absence of dedicated transmission line for Shanghai Electric Company Limited (SECL) plant, leads to load curtailment of Engro Power Thar Limited (EPTL) and Thar Energy Limited (TEL) due to inadequate transmission capacity. NTDC needs to complete its evacuations projects on priority so that any adverse impact on the power sector may be avoided.
The NEPRA report said that the duration of interruption was witnessed around 0.15 hours (9 minutes) in the year 2021-22 indicating 15.4% increase as compared to preceding year i.e. 0.13 hours.
NTDC reported 51 losses of supply incidents during the year 2021-22 which translates into total duration of 80 hours. As reported by NTDC, these outages include 3 major disturbances that accounts for an outage of around 3 hours and ENS of 4.62 million kWh. Around 50% of financial impact as indicated above is attributed to these 3 major incidents which is undesirable. In its report submitted to NEPRA, NTDC revealed serious lapses on the part of NTDC.
It was also observed that after the blackout of 9th January 2021, NTDC was directed to make certain improvements in its transmission network for the improvement of system reliability, stability and security of supply. However, recent events and multiple outages in NTDC’s network during the FY 2021-22 indicate that adequate measures have not been taken by NTDC in this regard.
The Authority allowed a colossal amount of Rs. 790 million to NTDC under the head of repair & maintenance (R&M) to ensure and attain optimal level of network reliability and sustainability. However, the monitoring activities such as field visits and checks carried out by NEPRA during the period reveal that southern part of the network is vulnerable to frequent outages that lead to major system disturbances owing to aging of equipment and tower collapses According to the report number of voltage violations for NTDC remained 185,497 for the year 2021-22 that indicate 54.5% increase as compared to 120,092 violations in the preceding year.
The frequency data as reported by NTDC indicated variation in frequency limits beyond the upper permissible limit of 50.5 Hz and highest frequency recorded was 50.66 Hz that comes out to be 1.3% variation against the allowed limit of 1% in the year 2021-22. However, NTDC has violated the prescribed limits 4 times for a total of 26 minutes. The complexity of the modern day power systems require automation for real time data acquisition enabling quick and intelligent decisions for supervision, monitoring and control of the transmission system. NEPRA has long been emphasizing a need to deploy modern SCADA System by NTDC to supervise and control the economic despatch of electric power generation which has still not turned up. The Authority has allowed Rs. 3400 million to NTDC in the last three years for installation and commissioning of SCADA system and services as per request of NTDC which is not been in field yet.
During 2021-22 the average number of outages per circuit for NTDC remained 0.10, showing an improvement of 10% over the previous year i.e. 0.11.