In the past few years, the focus of various government programmes in the transmission and distribution segments has been on network strengthening, modernisation and ensuring quality power supply. Substations, which convert voltage from high to low, and switchgear, which comprises devices associated with system control and protection, play a vital role in providing reliable supply. Various government programmes such as the Integrated Power Development Scheme (IPDS) and Deendayal Upadhyaya Gram Jyoti Yojana (DDUGJY) focus on the setting up of new substations and capacity augmentation of existing ones. Since the launch of these schemes in 2014, 442 new substations have been set up under the IPDS and 891 under the DDUGJY. Transmission utilities have also been focusing on the expansion of substation capacity. Around 345 GVA of substation capacity at voltage levels over 132 kV was at various stages of construction.
The IPDS, launched in November 2014, aims to increase the quality and reliability of power supply in urban areas. Broadly, the scheme entails the strengthening of sub-transmission and distribution networks in urban areas; metering of feeders, distribution transformers and consumers; IT enablement; and distribution network strengthening. The scheme includes the setting up of 1,033 new substations (award scope) and capacity augmentation of existing substations. According to PFC’s latest data, over 700 new 33/11 kV substations have been commissioned, adding around 7,000 MVA of transformation capacity with an average of one substation being commissioned every day since the launch of the IPDS. The capacity augmentation of the 1,200 existing substations has also been completed (the scheme entails capacity enhancement at 1,547 substations).
Launched in December 2014, the DDUGJY aims to strengthen sub-transmission and distribution networks in rural areas in order to provide 24×7 power supply. The key objectives of the scheme include network strengthening, metering, rural electrification, and decentralised distributed generation. As part of network strengthening, the scheme entails installing new substations and augmenting transformer capacity at the existing substations. The DDUGJY entails the setting up of 1,815 new 33 kV substations aggregating 13,115 MVA in capacity. As of December 2018, work at 891 substations aggregating 5,410 MVA in capacity was completed. Besides this, the scheme entails the augmentation of 1,634 33/11 kV substations aggregating 8,225 MVA in capacity. Of this, augmentation has been completed at 942 substations aggregating 4,204 MVA in capacity.
As per the TARANG dashboard, substation capacity of 345,613 MVA was under development across voltage levels over 132 kV as of March 2019. Intra-state substations accounted for the majority share (71 per cent) in the total under-development substation capacity. Voltage-wise, the major share (44 per cent) of under-development substation capacity is at the 400 kV level (150; 590 MVA), followed by the 220/230 kV level at 31 per cent (108; 824 MVA). A significant chunk of the substation capacity, aggregating 109,643 MVA, is scheduled to be commissioned during 2019-20. In terms of progress, around 70 per cent of tracked substation capacity falls in the range of 0 to 10 per cent progress, that is, construction has not yet commenced and/or work packages have not been awarded. Just about 15 per cent of tracked substation capacity has made over 70 per cent progress.
At the interstate level, as of March 2019, Powergrid’s under-construction substation capacity included AC transformer capacity of 63,000 MVA and HVDC substation capacity of 11,000 MW. Its key under-construction transmission projects are the 800 kV Raigarh and Pugalur HVDC substation (6,000 MVA), and the 800 kV Champa and Kurukshetra HVDC substation (Poles-3 and 4) (3,000 MVA). Meanwhile, at the intra-state level, transcos with the highest under-construction substation capacity included Tamil Nadu Transmission Corporation Limited (36,035 MVA), Gujarat Energy Transmission Corporation Limited (30,810 MVA) and Uttar Pradesh Power Transmission Corporation Limited (25,800 MVA).
To conclude, the implementation of various programmes has led to an improvement in the T&D segments including the expansion and strengthening of networks. This will go a long way in achieving the government’s objectives of providing 24×7 power supply.