Improving Grid Efficiency: Transcos’ perspective

India’s transmission network has been steadily expanding over the past few years to facilitate the transition to renewable energy.  Given the ambitious climate change targets of achieving 500 GW of non-fossil fuel capacity by 2030, significant investments are under way to upgrade the country’s grid infrastructure at the interstate and intra-state transmission levels. As transmission utilities gear up for handling bidirectional flows and larger volumes of intermittent renewable energy, they are adopting advanced technological and digital solutions to ensure grid stability and enhance agility. Industry experts from leading transmission companies (transcos) comment on the sector’s progress, key challenges and future outlook…

What is your assessment of the current state of the power sector and specifically, the power transmission segment?

Kiran Gupta

In line with India’s ambitious targets of decarbonisation and achieving clean energy goals (based on non-fossil fuels), the power transmission segment is ex­pan­ding rapidly. In addition to the ex­pa­nsion of the physical network, the sector is undergoing technological transformations, with utilities implementing solutions such as flexible AC transmission systems and battery energy storage systems to enhance grid reliability due to the growing integration of highly variable renewable energy generation. The­re is also a shift towards new and advan­c­ed technologies such as internet of th­ings, artificial intelligence (AI) and ma­chine learning to enhance the admi­ni­stration of the quickly expanding transmission network. The sector’s phenomenal growth over the past several years can be attributed to a number of factors, including increased budgetary resour­ces, sizeable private investments, supportive governmental initiatives and rising national demand.

Considering India’s rapidly growing po­wer generation capacity, which is ex­pected to double by 2030 with 500 GW being contributed by renewables (280 GW from solar, 140 GW from wind and 80 GW from pumped storage projects), up­gra­ding the transmission system is impe­rative to accommodate the increased energy load. The upkeep of the transmission network, which was once considered a steady job with a lifespan of about 35 years, now necessitates extensive and cooperative modifications due to the catastrophic effects of climate change, cy­c­lones and windstorms.  These reforms are essential to ensure that the transmission network remains the bedrock of the power sector. Additionally, with increasing focus on the development of green hydrogen and offshore wind generation in power transmission planning, a green energy corridor must be established for the evacuation of such power.

In recent years, the government and regulators have implemented a number of innovative policy and reform initiatives in the transmission sector. In July 2022, the Central Electricity Regulatory Com­mission notified the Connectivity and General Network Access (GNA) to the Inter-State Transmission System (ISTS) Regulations by introducing a new paradigm for transmission planning. The tra­nsition to GNA would provide the much-needed flexibility to state entities for purchasing electricity under contracts of varying durations without the limitations of ISTS network availability. Gene­rators will also benefit from enhanced sales flexibility, as they will not have to specify target beneficiaries.

B.B. Mehta

The transmission segment plays a key role in the development of the power se­ctor since the penetration of renewables is increasing significantly. Typica­lly, renewable energy plants are situated in re­mote areas, necessitating the installation of additional transmission lines. With the growing energy requirement in the sector, the transmission segment pl­a­ys a crucial role in meeting the increasing demand.  Renewable projects can be completed within a significantly shorter time frame compared to thermal or nuclear projects. As a result, this leaves a limited timeline for completing transmission projects. The escalating commercial value has transformed the task of securing right of way (RoW) into a formidable challenge. Therefore, we are actively seeking government support to address this matter, as it is absolutely essential to ensure the timely and successful completion of the transmission network for renewable projects.

In addition to RoW challenges, it is wor­th noting that in Odisha, a significant portion of land falls under forest jurisdiction. Acquiring the necessary appro­vals and clearances from forest authorities, along with implementing remedial actions such as afforestation on alternative land, often consumes substantial ti­me. This, in turn, leads to delays in tra­n­s­mission projects. In our pursuit of transitioning towards a greener and cleaner energy landscape for both the state and the nation, it is imperative to recognise the pivotal role that transmission systems play. They serve as a critical backbone for efficiently channelling power from green energy sources to load centres. It is crucial that we offer our su­pport in addressing the challenges faced by the sector.

Upendra Pande

In recent years, India has undergone a remarkable transformation, transitioning from a power-deficit country to one with a surplus of electricity. Further, greater focus on the development of new renewable energy resources has helped us diversify the energy mix and reduce the dependence on fossil fuels. Gujarat’s po­w­er generation is characterised by a judicious blend of conventional and renewable energy sources. In the past decade, its power sector has witnessed a significant rise, increasing from an installed capacity of approximately 14 GW in 2010 to a staggering 37 GW in 2023. This phenomenal growth has been underpinned by a robust power infrastructure, featuring a seamlessly connected transmission network with 2,203 substations, 73,054 ckt. km of transmission lines and 162,906 MVA of transformation capacity (as of March 2023), along with an exceptionally reliable distribution system. Further, as the pace of the energy transition accelerates, the next 5-10 years are shaping up to be a period of significant transformation. To adapt to the changing energy lan­d­scape, the power transmission segment is also undergoing a transformation. The sector has redefined itself, driven by the increase in renewable energy capacity, which is often established in locations distinct from earlier conventional generation sources. This shift underscores the importance of the transmission segment within the entire power sector.

What, according to you, are the emerging nee­ds and requirements of the power transmission sector?

Kiran Gupta

In the evolving power transmission sector, priorities encompass grid modernisation, resilience to extreme weather, capacity expansion, energy storage integration, cybersecurity, rural electrification and grid strengthening to promote clean energy adoption and community engagement. Transmission utilities are increasingly adopting predictive maintenance strategies, where actions are taken based on equipment health forecasts using data analytics tools, enabling objective decision-making. Further, th­ere is a need to implement measures for upgrading and augmenting ISTS and sub-transmission networks. Reforms aimed at eliminating the need for licen­ces when establishing dedicated transmission lines for larger consumers and energy storage systems (ESSs) could significantly enhance the participation of captive power producers. This would si­mplify the process of building transmission and evacuation infrastructure, es­pecially with the expected substantial expansion of green energy capacity.

Transmission companies are also adopting technological tools such as drones with thermovisual scanning, high resolution videos and corona cameras for patrolling transmission lines, substations and reactors in real time. Utilities can now rapidly and effectively identify vulnerabilities in the transmission grid by using drones. Aerial surveillance as well as remote airborne inspection and scanning devices are more effective, less ex­pensive and quicker than traditional line patrolling methods based on tower-top patrolling and on-ground procedures. These images can be used to develop in­telligent digital twins integrated with AI, which can accurately recreate transmission lines and towers to optimise asset maintenance and records. A technological shift in the transmission segment is the need of the hour to facilitate the on­go­ing energy transition. Utilities must prepare a technology roadmap to ensure that the grid operates in a smooth and reliable manner.

B.B. Mehta

The transmission sector is undergoing a significant transformation in its overall operational pattern. While achieving an impressive availability rate of over 99 per cent, there is still room for improvement in terms of reliability.  To deliver quality power, it is crucial that we utilise the transmission network in a manner that ensures the transferred power conforms to grid parameters as specified in the gr­id code. Ensuring power quality has be­come an essential requirement in the pre­sent time. Furthermore, we should aspire for solutions that contribute to grid stabilisation. The transmission segment should consider incorporating sm­art grid features, such as automatic de­mand-side management and reactor deactivation. Several companies, inclu­d­ing Hitachi Limited, have presented viable solutions in this regard for automatic grid stabilisation.

Moreover, optimising the quality of power delivered to discom levels can le­ad to more efficient asset utilisation. Nu­merous transmission projects currently remain underutilised at both the central and state levels. It is imperative to leverage these existing networks by impleme­nting storage solutions at nodal points of substations. This approach will en­han­ce line loading and asset utilisation. By strategically planning storage solutions within the transmission networks, particularly in areas with lower loads, we can significantly improve network utilisation without the need for establishing new infrastructure.

Upendra Pande

As a significant step towards a cleaner, bri­ghter and sustainable energy future, Gujarat Electric Transmission Corporat­ion Limited (GETCO), a state transmiss­ion utility, has proactively identified and acknowledged the needs, requirements and challenges in the power sector, which are listed below.

Quick, robust and expansive transmission network: Renewable energy projects can be deployed rapidly but the es­tab­lishment of transmission infrastructure often encounters delays due to obs­tacles like RoW and clearance app­ro­v­a­ls. Consequently, there is a significant need for expeditious grid expansion to prevent grid congestion and curtailment of ex­cess energy, and ultimately achieve re­ne­wable energy targets. In view of these cha­llenges, the Green Energy Co­rridor Phase I project, which aims to harness 4,000 MW of renewable energy capacity with eight substations and approximately 1,800 ckt. km of transmi­ssion lines, is nearing completion. Fur­th­er, under Phase II, to facilitate around 4,500-5,000 MW of renewable energy capacity, we have planned seven substations and approximately 2,500 ckt. km of transmission lines, and work is in pro­gress. Additionally, the Gu­ja­rat Electri­city Regulatory Commis­sion has introduced a public-private partnership mo­del to accelerate the pro­cess of setting up transmission in­frastructure by allowing multiple transmission licen­se­es and incentivising private investments in this endeavour.

Comprehending the challenge of massive renewable integration: While rene­wable energy sources offer numerous benefits, there are challenges associated with their integration due to their intermittent and variable nature. Inte­grating renewables requires significant upgra­des and investments in grid infrastructure along with the implementation of cost-effective energy storage solutions, smart grid technologies, and advanced digitalisation and data analytics tools. In view of these challenges, we ha­ve integrated the following technological ad­van­cements to improve grid efficiency and reliability:

  • Installed a ±120 MVAR static synchronous compensator (STATCOM) at the 220 kV Timbdi substation.
  • Installed a substation automation system at 62 substations, with 30 substations in the pipeline.
  • Six 66 kV, four 220 kV and six 400 kV geographic information system (GIS) substations are operational.
  • 220/66 kV Sevaliya, a fully digital substation, is under implementation.
  • Implemented cybersecurity in IEC 61850-based substation automation.

To address the challenge of utilising the vast energy potential and minimising the issues associated with the massive integration of renewable energy into the grid while avoiding the need for costly ESS, GETCO will shift the agricultural demand during the daytime (Kisan Suryoday Yojana) to align it with peak solar hours. The implementation of the Kisan Suryo­day Yojana across the entire state will be carried out in a phased manner.

Global need for environmental sustainability: As a part of our commitment to­war­ds the national goal of addressing climate change and reducing our carbon fo­ot­print, we have taken the following initiatives:

  • Planned the development of a 66 kV green substation with power transformers and instrument transformers using ester oil, along with circuit brea­kers that do not rely on SF6 gas.
  • Planned a compact GIS, providing a space-saving and reliable solution particularly suited for urban and densely populated areas.
  • Utilised narrow-base towers, especially in urban areas, and adopted 220 kV monopoles for shifting of 220 kV transmission lines.
  • Optimised RoW by employing M/C towers.

What is your outlook for the segment in the near to medium term?

Kiran Gupta

We foresee a transformative period characterised by several key trends and priorities. As we migrate towards renewab­les, innovation and technological ad­van­­cements will be at the core of power transmission. Recently, the National Com­mittee on Transmission gave its approval for six transmission projects worth Rs 640 billion. These projects are poised to play a pivotal role in connecting green energy installations, aligning with the nation’s commitment to renewable energy adoption.

The Ministry of Power has set targets to complete the development of 27,000 ckt. km of ISTS lines and 28 substations, with an estimated capex of Rs 700 billion under the Pradhan Mantri Gati Shakti Na­tional Master Plan, by December 2024. Overall, capex in the segment is es­timated at Rs 3,040 billion between 2020-25, with the National Infrastruc­ture Pipe­line and state utilities expected to acc­ount for a major share (62 per cent) in the capex. In addition, the segment is expected to see the uptake of advanced technologies to improve grid capacity, resi­lience and stability. By using analytics, utility companies can gather real-time data from various equipment sources, en­abling them to derive valuable insigh­ts. These insights assist companies in an­ticipating and predicting equipment failures. Analytics can be applied to examine collective data from a range of systems, including the remote operation of substations through supervisory control and data acquisition (SCADA), the utilisation of drones and robots for the construction and inspection of transmission assets, cybersecurity, ESS, and advanced metering infrastructure.

In the previous month, the country ac­hieved a remarkable milestone, with peak electricity demand touching a record high. Given the growing installed generation capacity and demand, there is a critical need for upgrading the transmission network. Establishing a new transmission corridor would not only be cost-intensive but can also address challenges related to stringent RoW requirements, and dynamic laws and regulations. Our commitment to meeting this demand aligns with our mission to provide reliable and accessible power to all.

B.B. Mehta

The outlook for this segment highlights an increasing demand for liability, redundancy and the assurance of power quality. The adoption of new technologies such as GIS substations, state transmission asset management centres, digital substations and SCADA-based substations is the need of the hour. Original equipment manufacturer (OEM) support often fails to meet expectations, resulting in network unavailability or unresolved problems for extended periods. Hence, I believe that embracing these new tech­no­logies effectively requires a robust pa­rt­nership between OEMs and end-users, ultimately yielding more favourable outcomes. Additionally, government intervention is essential to promptly address RoW issues and forest reservations.

A significant upcoming development in the transmission sector is asset monetisation, which requires close attention. To promote further growth, we should encourage increased private sector participation in the transmission industry. In contrast with the generation sector, where over 50 per cent of generation activities are overseen by private operators or players, the transmission sector has comparatively fewer private entities operating on the tariff-based competitive bidding route.

Furthermore, within the transmission sector, a critical subset is grid manage­me­nt. There is a pressing need for en­hancing the utilisation of transmission assets to ensure optimal grid management. To achieve this, it is imperative to integrate essential tools, software and co­ntrol systems into the transmission net­­work. These implementations will not only improve grid reliability and po­wer quality but also enhance the overall usage of the transmission network.

The transmission sector should disseminate its best practices throughout the state with the assistance of the Central Transmission Utility and regional agencies. Given that the transmission segment bridges the gap between generation and distribution, it is crucial to prioritise its adoption of new technologies, accelerate project execution and add­re­ss underutilised assets. Once establi­shed, transmission assets cannot be re­located, making it essential to maximise their value. In many cases, these assets fall short of their design capacity due to generation and loading patterns. A timely and pertinent solution is to impleme­nt storage solutions around these un­derutilised assets, addressing a critical need in the sector.

Upendra Pande

In view of the above crucial aspects for the future, we have charted a visionary 10-year perspective plan that seamlessly integrates pivotal components like add­ressing distribution utilities’ demand for the next decade, integrating 65 GW of renewable capacity by 2032 and providing daytime power supply to the agricultural sector. Furthermore, we intend to increase renewable energy capacity integration to 100 GW. By 2032, we envision the addition of over 1,000 substations along with over 30,000 ckt. km of transmission lines at various voltage levels. To ensure the stability and reliability of the grid, 17 STATCOMs and approximately 15,000 MVAr reactive power support at the 11 kV and 66 kV levels have been planned. To optimise the efficiency of its existing assets and establish a resilient transmission network, over the next 10 years, various renovation and modernisation works have been plan­ned. These include the replacement of conductors with high capacity ones and the augmentation of about 450 substations. Although Gujarat is geographically endowed with significant solar and wi­nd energy generation potential, its long coastal lines face the substantial threat of cyclones. Taking lessons from the damage caused by two recent cyclo­nes, we have planned a cyclone-resilient transmission system by adopting high wind zone infrastructure, shifting of the overhead 66 kV transmission system to underground cables and the introduction of more GIS substations in coastal areas to ensure transmission infrastructure resilience. GETCO’s forward-thinking approach is a testament to its commitment to meeting the evolving needs of Gujarat’s power sector. As the country strives for a cleaner and more sustainable energy future, Gujarat is stepping forward to become a source of inspiration and a model to emulate in the power sector.