Sunday July 03, 2022

First HVDC transmission line tested with full load of 4,000MW

By Our Correspondent
August 15, 2021

LAHORE: Pakistan on Saturday launched the trial run of its first high voltage direct current (HVDC) transmission line with the full load of 4000 megawatts (MW), a landmark ahead of its commercial operation date (COD) next month.

Dubbed as flagship China Pakistan Economic Corridor (CPEC) project, 660kV Matiari-Lahore HVDC Line is the largest ever transmission sector project of the country in terms of its capacity as well as one of the longest in distance, connecting power generation units in the south with load centers upcountry.

“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,” said an official of National Transmission and Despatch Company (NTDC).

“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 official added that the trial operation was being carried out through NTDC transmission system.

“The Project has a design capacity of 4,000MW and will help evacuate power from cheaper Southern coal power plants and deliver it to load centers in the North of the country.”

Above all, the official said, the ongoing trial operation of the transmission line helped in contributing the record highest power transmitted on August 11, 2021 at 24,467 MW through the national grid.

“In 2020, peak load sustained by the national grid was 23,370MW for one day and in 2018 it was just 20,811 MW. With the launching of HVDC Matiari-Lahore Transmission Project, power dispersal capacity of the national grid has seen a massive jump of 4000mw in one go,” said an official.

He added that the ongoing trial operation marked one of the last steps in the completion of the project.

“In this last stage it will be trial-operated for a few days continuously at various power levels and under various configurations to test it in full running condition,” said the official.

Furthermore, the Capability Demonstration Test of the Project will also be performed during this period.

It is informed that the equipment debugging, station commissioning, and system commissioning up to the level of high power bipole testing of the project has already been completed, certified by both the Independent Engineer from Italy and Owner Engineer from Canada.

Despite Covid-19 pandemic, the overall work was completed by end of 2020. Earlier, the project was expected to be commissioned by March 2021 after going through trial run. However, after reaching an amicable solution, the contractor and NTDC agreed in writing to conduct trial run during peak load of summer months with COD in September 2021.

It may be noted that after completing feasibility study of the project, NEPRA determined tariff of the long-distance line while its implementation agreement along with the transmission services agreement initialed in December 2016. Agreement was signed between PPIB and State Grid of China on May 2018 and Financial Close was achieved on 27th February 2019.

The Matiari-Lahore transmission project is an 878km-long, 660kV high voltage direct current (HVDC) transmission line being operated under the framework of China-Pakistan Economic Corridor (CPEC).

It is also said to be the first private sector transmission project being developed in the country. The approximate cost of the project has been estimated at $1.65billion.

It is being developed on a build, own, operate and transfer 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, a public sector enterprise.

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.