Micro, mini grids suggested to energise rural areas

ISLAMABAD: The National Transmission and Dispatch Company (NTDC) is overhauling its infrastructure by building transmission lines and additional grid stations to rid the Pakistan’s power sector of the perennial problem of transmission system constraints.

Speaking to WealthPK, the NTDC spokesperson said that during the last five years, the country’s energy sector has undergone a significant investment phase to better meet the rising demand for power across the country.

“A major power transmission infrastructure project has come about in the shape of the 878-kilometre 660KV high voltage direct current (HVDC) Matiari-Lahore Transmission Line. This line has been built under the China-Pakistan Economic Corridor, which is a major component of the larger Belt and Road Initiative.

This is the largest-ever transmission sector project of the country in terms of its capacity and the distance,” the NTDS spokesperson explained.
“It is the basic need and right of the people to get power supply, whether they live in urban centres or in rural areas. However, the National Grid Company’s (NGC) cost of transmitting energy to rural places is often too expensive, making it financially unfeasible.”

To overcome this problem, micro/mini grids have been suggested as a feasible way to energise rural areas when there is no central grid accessible, whereas the national grid is utilised to deliver power to load centres and densely-populated areas, the NTDC spokesperson said.
The main reason for the under-utilisation of efficient power plants in Pakistan has been the constraints of transmission and distribution networks such as overloading of transmission lines, insufficient transformation capacity of power transformers and outages of transmission lines.

Overloading of transformers beyond their rated capacity is one of the most serious problems in the power transmission system. As a result, transmission lines are subject to forced outages. Around 49% of 500/220KV transformers and 57% of 220/132KV transformers were overloaded (above 80% load) in fiscal year 2020, according to NTDC.
For smooth, transparent and efficient operations, the National Electric Power Regulatory Authority has recommended that an independent system operator (SO) should be established immediately apart from the NGC. The SO should quickly implement a state-of-the-art SCADA system for the required transparency and efficiency in real-time system operation.

Nepra stressed the need to equip the NPCC (National Power Control Centre) with adequate human, technical and financial resources to perform its functions effectively in the competitive market.
According to the Indicative Generation Capacity Expansion Plan (IGCEP) 2020-21, the national grid, which acts as the backbone of the country’s power system, consisted of 500KV and 220KV lines and the associated grid stations. The total 500KV transmission network during 2019-20 extended well over 7,470 circuit-kilometre supported by 16 grid stations with 25,460MVA transformer capacities.

The 220KV transmission network extended over 11,281 circuit-km supported by 45 grid stations with an aggregate total transformer capacity of 30,440MVA. Distribution networks inclusive of 132KV, 66KV, and 33KV voltage levels, collectively extended over 37,735km, and were supported by 928 grid stations with a total capacity of 53,263MVA in delivering the electricity to end users dispersed around the country. This is shown in the table above.

INP