Power Grid Corporation of India Limited (Powergrid) has played a pivotal role in the country’s transmission sector – from the formation of a single unified national grid to expanding cross-border interconnections as well as augmenting the interstate transmission system (ISTS). The company is now venturing into areas such as intra-state transmission, energy storage and electric vehicle (EV) charging, among others. In an interview with Power Line, Abhay Choudhary, Director (Projects), Powergrid spoke about the power sector’s achievements, evolution of the transmission segment, the company’s future plans, and more…
What have been the most noteworthy achievements of the power sector over the past 25 years?
The power sector, 25 years back, was governed by the Electricity (Supply) Act, 1948 and was severely constrained due to the poor infrastructure and financial health of the state utilities; electricity supply was much lower than demand, electricity transfer across the country was limited and the sector was in dire need of investment and resources.
In the past 25 years, the sector has undergone a positive radical transformation. There have been policy and regulatory reforms through the Electricity Act, 2003, the National Electricity Policy (NEP), 2005, the Tariff Policy, 2006, the creation of independent regulatory bodies at central and state levels, unbundling of state electricity boards and delicensing of generation, open access, etc.
The past 25 years are characterised by the addition of a large amount of generation capacity, particularly in the private sector, matched with commensurate development of the interstate transmission capacity. The installed capacity has increased from about 85,000 MW to close to 400,000 MW. The per capita consumption, which was less than 500 kWh, is now more than 1,200 kWh. The power deficit, which used to be more than 10 per cent, is now negligible. All the five regional grids have been integrated to form a rigid synchronous national grid. Now we are “One Nation One Grid One Frequency” and gradually moving towards “One Price”. Grid discipline has been a notable achievement. Further, the establishment of power exchanges has led to the development of a short-term market for electricity at competitive prices.
The impetus given by the Government of India (GoI) to greener energy has resulted in a quantum growth in renewable electricity capacity. Renewable generation (other than hydro), which was less than 1,000 MW, is now more than 100 GW and moving towards 450 GW by 2030. The overall growth in the sector, along with the government’s vision, has shown a remarkable improvement in the distribution sector. All households are 100 per cent electrified and are moving towards 24×7 electricity supply.
“We should think of creating transmission highways, with anticipated generation pockets and projected load centres. Transmission has to lead generation for its timely availability.”
How has the transmission segment evolved in the past 25 years?
In the past 25 years, the transmission segment has seen phenomenal growth in terms of ckt. km as well as technology. The first and foremost evolution is the formation of the national grid, thus realising the dream of “One Nation, One Grid and One Frequency” from the earlier five grids and five frequencies. Interregional transfer capacity has increased from near zero to more than 110,000 MW. To facilitate renewable energy growth, various green energy corridors and solar park systems have been planned and executed by Powergrid.
Earlier, most of the transmission used to be at the 220 kV level, with a few lines at the interstate level at 400 kV, the highest voltage in the country 25 years back. Further, only AC links were there in the system. The past 25 years have seen a paradigm shift in the technological face of the transmission sector. Higher voltage levels such as 765 kV and 1,200 kV were introduced in the country. Starting from a limited capacity (500 MW) high voltage direct current (HVDC) back-to-back links, now we have many 6,000 MW, ±800 kV HVDC bipole links across the country. Thus, the Indian grid has shifted from 220 kV to 400 kV to 765 kV in high voltage alternating current with about 450,000 ckt. km, including 47,000 ckt. km at the 765 kV level and 9,500 ckt. km at the 800 kV HVDC level on an all-India basis. In HVDC also, state-of-the-art technologies such as metallic return, 320 kV voltage source converters (VSC) have been deployed.
Besides the national grid, many international transmission links have been implemented by Powergrid as a step towards the SAARC Grid. Now, India is well connected with Bangladesh, Nepal, Bhutan and Myanmar.
On the operations and maintenance (O&M) front, various state-of-the-art O&M practices have minimised transmission losses and unscheduled outages, resulting in the transmission system availability consistently above 99 per cent, which is at par with international standards. Some of the latest technologies that are being used by Powergrid are aerial patrolling, GIS mapping, UAV/drones, emergency restoration systems, hotline maintenance, digital substations, etc.
Transmission sector policies have also undergone a sea change. Powergrid has set up state-of-the-art regional load despatch centres and the National Load Despatch Centre to enable independent grid operations. Implementation of an all-India centralised method for sharing transmission charges and losses across the country has facilitated the growth of the national grid. The sector has seen a tremendous response from private sector players. Success of the infrastructure investment trust (InvIT) has reinforced investors’ confidence in the Indian transmission sector.
This growth and evolution of the transmission sector has played a special role in delivering generated energy to consumers in a reliable and efficient manner, reducing the cost of power procurement, and enhancing flexibility, system reliability, and the development of the power market.
“To facilitate renewable energy growth, various green energy corridors and solar park systems have been planned and executed by Powergrid.”
What will be the biggest challenge in transmission over the next 25 years? What is the way forward?
As per recent trends, I feel that right-of-way (RoW) for laying transmission system is going to be the biggest challenge over the next 25 years. Other significant challenges are land acquisition for new substations, integration of projected renewable capacity in the grid, management of such a complex grid and the ageing infrastructure. Another major challenge is the cybersecurity of the connected transmission systems. The entire sector will need to be more vigilant and work towards enhancing the security of all stakeholders involved.
We need to adopt technology to enable more power transfer over existing RoW such as multicircuit towers, high tension-low sag conductors and higher voltage levels. Also, we should think of creating transmission highways in advance, such as the National Road Highways, with anticipated generation pockets and projected load centres. Transmission has to lead generation for its timely availability. We should work towards implementing smart grids, which have a real-time monitoring system with self-healing, automation for substations, advanced metering infrastructure, net metering, demand-side management, etc., on a very large scale. We should also work to match the development of sub-transmission and distribution networks so that the maximum benefits of the transmission system are availed of by the consumer.
What will be the most promising transmission technologies in the next 25 years? What are some of the new technologies being planned by Powergrid?
Powergrid has always been in the forefront of introducing new technologies in the transmission sector. In the next 25 years, technologies that address the challenges faced by the transmission sector would be in demand. Thus, technologies that reduce the requirement of human intervention over the length of line seem to be the most promising to me. As far as Powergrid is concerned, we are working on many technological initiatives. Some of these are the development of a robotic drone that can inspect lines with complete autonomy; development of many data analytics-based systems to help assess the life cycle of various equipment such as integrating current transformers and circuit breakers, with a feature to perform all financial calculations; development of a nano particle doped oil for use in transformers, which is expected to have better operational characteristics than the currently used synthetic oils; installation of a cybersecurity test bed to test the security of intelligent electronic devices in-house; image processing of satellite and drone images related to transmission lines for vegetation management to streamline and reduce manual line patrolling; development of analytics for utilisation of phasor measurement unit data for wide area protection and control application; and full digital substation and centralised testing of control and protection schemes.
What have been Powergrid’s biggest achievements in the past few years?
As a major player in the transmission sector, Powergrid has been building transmission infrastructure that has enabled various initiatives of the GoI – open access, real-time power trading and Power for All – as well as a quantum leap in renewable energy integration. Powergrid has created a strong and rigid national grid, which has connected all the regions of the country through high capacity transmission highways. Interregional capacity has been enhanced to more than 110,000 MW.
In the past six years, Powergrid has added more than 53,000 ckt. km to the Indian grid. A number of 765 kV D/C corridors and high capacity HVDC links have been implemented all over the country. Major among these are the North East-North/ West Interconnector Project, consisting of the world’s longest and first 6,000 MW ±800 kV HVDC multi-terminal HVDC project between Agra, Alipurduar and Biswanath Chariali. Another high capacity HVDC link has been implemented between Champa and Kurukshetra which is the world’s first ±800 kV 6,000 MW parallel convertor having single 12 pulse convertors of 800 kV DC and a dedicated metallic return conductor running on the same HVDC tower. The ±800 kV 6,000 MW Raigarh-Pugalur-Trichur HVDC link has been commissioned, which consists of and consists of the world’s first ± 320 kV, 2,000 MW VSC HVDC project, having a combination of overhead and underground cables.
In addition to these, Powergrid has created green energy corridors, a transmission system for solar parks and 11 renewable energy management centres to give a boost to renewable energy capacity targets. Powergrid has successfully implemented many transmission projects under the tariff-based competitive bidding route. It has also successfully executed an InvIT – the first and the largest by any central public sector enterprise. Powergrid was conferred Maharatna status last year by the GoI.
What will be Powergrid’s focus areas in the coming years? What are some of the new opportunities that the company is pursuing?
The GoI is promoting large-scale addition of generation capacity from renewable sources and has set an ambitious target of installing 225 GW by 2024 and 450 GW by 2030. Transmission systems are key enablers for this development. Towards this, the requirement of ISTS for renewable energy projects from potential solar energy zones and potential wind energy zones has been identified. Powergrid is sensing a lot of business opportunities in the development of ISTS projects for renewable addition. Renewable generation projects have a very short gestation period (18-24 months) as compared to the longer gestation period of conventional generation projects (four to five years). Therefore, one of the focus areas of Powergrid is to create processes so that the completion period of transmission projects matches that of renewable power projects.
Another area of focus has been to explore the business opportunities available in the intra-state sector. The company is contemplating the formation of partnerships/joint ventures with interested states for intra-state transmission, sub-transmission and distribution, improvement of 33 kV system under transmission, smart metering through IntelliSmart/Energy Efficiency Services Limited, etc. Further, the company is looking forward to opportunities for moving towards a smart grid, with grid-connected renewable energy, energy storage systems, rooftop renewables, etc.
Powergrid was one of the first movers in the EV charging industry in India. In the next few years, we expect EV adoption to grow and as a result, we are looking to install more EV charging stations throughout the country. Powergrid is also exploring the option of venturing into other business areas of solar power generation, data centre business, etc.
The growth of renewables would mean that the severity of the “duck curve” in power demand will gradually increase with time. This will necessitate the use of grid-level storage. Powergrid will look into installing bigger grid-level storage in future.
What is your outlook for the transmission industry in the next 25 years?
India has taken remarkable strides to ensure electricity access to every household, with a key focus on reforms for affordable and sustainable energy systems. The success of the energy policy and implementation can be gauged from the standards of availability, access and sustainability. With the increase in per capita consumption, power demand is slated to increase in the next 25 years.
Our energy mix is changing and renewables are set to take over the generation crown from conventional projects in a decade. Moreover, the ageing conventional projects are in the process of being phased out. At the same time, real-time trade of energy is becoming more prominent. We will need to enhance ISTS capacity to enable power from Ladakh to reach Kanyakumari or any other region affordably.
To match the investment in ISTS, a lot of investment is required in sub-transmission and intra-state transmission systems. Thus, the outlook for the transmission industry is bright, driven by renewable energy as the prime mover of the growth engine. A number of ISTS projects are on offer and huge investments are needed for achieving the goal.