The National Transmission and Despatch Company (NTDC) has tested Pakistan’s longest high voltage direct current (HVDC) transmission line with its full load capacity of 4,000 MW.
The full capacity load is a landmark achievement as it comes almost a month before the commercial operation date (COD) of the transmission line. The HVDC line transcends a geographical length of about 900 km, marking the start of an era of long-distance power transmission in the country. It is a unique project in the sense that it introduces HVDC technology for the first time in the national grid, enriching the technology mix of the grid.
The project of the HVDC transmission line is the first private sector transmission project being developed in the country. The approximate cost of the project has been estimated at $1.65 B. The project is being developed on a build, own, operate and transfer (BOOT) basis by the State Grid Corporation of China through the special purpose company Pak Matiari-Lahore Transmission. After 25 years of operations, the transmission line will be transferred to NTDC.
One of the major stabilizing effects of the HVDC transmission line on the national grid has been provision of leverage to NTDC to avoid breakdowns due to overloading of the transmission system. It will act as a balancing tool to keep voltage profile within the permissible frequency limit, while drawing power from hydropower projects in North and thermal power units in South.