The transmission system is a crucial component that connects the generating stations to the distribution system, enabling the consumers to receive power. In India, the distribution of energy resources, including renewable, hydropower, and coal, is not uniform. While hydro energy resources are predominantly found in the Himalayan Range in the country's northern and northeastern regions, coal deposits are primarily found in the country's central and eastern regions. Most renewable resources, including wind and solar potential, are found in states like Gujarat, Andhra Pradesh, Tamil Nadu, Karnataka, Rajasthan, Maharashtra, and Ladakh, among others. The country's main load centers are found in its central regions, which include the North, West, and South. Because of this uneven distribution of resources, a reliable transmission infrastructure had to be established, along with inter-regional corridors, to enable the smooth flow of power from surplus to deficit regions and districts. Through this, different consumers dispersed around the nation can access power generation from any place in the nation.
Over time, the transmission system has expanded through intrastate and interstate networks, enabling power evacuation from generating units to load centre. 'ONE NATION', 'ONE GRID', and 'ONE FREQUENCY' was accomplished by our country on December 31, 2013, when the 765kV Raichur-Solapur Transmission line was commissioned, synchronizing the Southern Region Grid with the rest of the Indian Grid. The process of gradually integrating regional grids began in 1992. Transmission congestion did, however, impose limitations on market operation, leading to market fragmentation and disparities in prices across different locations. Transmission congestion limited roughly 16% of the electricity exchanged through power exchanges in 2013–14. Furthermore, the Ladakh region, which was strategically significant, was not connected to the national energy system.
The Current Government has emphasized having a transmission network free of congestion, enabling seamless power transfer from surplus to deficit regions. As a result, transmission lines and inter-regional capacity have been added, steadily strengthening the nation's transmission network. As of August, 2023 the nation boasts one of the biggest synchronously integrated power networks globally, encompassing 4,74,998 ckm of transmission line and 11,96,883 MVA of transformation capacity. In addition, since 2014, the inter-regional capacity has grown by an astounding 212% to 1,12,250 MW.
The growth of the nation's electricity sector has benefited from the expansion of transmission capacity. Here are a few of the more notable ones:
1. Conveyance, the market splitting and congestion that occurred earlier in 2014 have now become uncommon, leading to the discovery of a single price for the power market. The percentage of Unconstrained Clear Volume, or the amount of electricity that cannot be cleared in power exchanges, has decreased from 16% in 2013–14 to just 0.06% in 2020–21.
2. In January 2019, the 220 kV Srinagar-Leh line was put into service, connecting the high-altitude border territories of Ladakh to the national electrical grid. This made it easier for the residents of Ladakh to get reliable power from the national grid around the clock.
3. The North Eastern Regional Power System Improvement Project (NERPSIP) and the Comprehensive Scheme for Strengthening of Transmission & Distribution in Arunachal Pradesh and Sikkim, two Central Sector Schemes, have been implemented, strengthening the transmission and distribution infrastructure of our North Eastern States, including Sikkim. By putting these plans into action, the North Eastern Region's state electricity grids would become more reliable and end users would be able to use the grid around the clock.
The power industry's developments highlight the necessity of implementing the National Power Grid more quickly to facilitate both scheduled and unscheduled power exchanges. Additionally, open access must be provided to promote competition in the power market.
With the commissioning of the 765kV S/c Raichur – Sholapur line on December 31, 2013, a countrywide synchronous power grid connecting all five regional grids was constructed in light of the aforementioned information. "POWERGRID is fortifying its transmission network to create inter-State and inter-regional connections to augment the National Grid's capacity in a timely manner, guaranteeing the best possible utilization of energy resources that are distributed unevenly."7,200 MW of inter-regional (IR) transmission capacity were added in FY 2021–2022, bringing the total nationwide capacity to 1,12,250 MW (as of Jan'23).
In terms of both GDP and power usage, India is currently one of the world's fastest developing nations. Meeting the energy demands of rapid economic expansion and the world's roughly 1.3 billion electrical users is a challenge. For the smooth flow of electricity from generating stations to load centers (as per the Electricity Act, 2003) and for the best possible use of the nation's resources, an effective, coordinated, economical, and robust electricity system must be developed in order to provide affordable, dependable, uninterrupted (24/7) and quality power for everyone. The transmission system creates the connection between the generation source on one end and the distribution system, which is connected to the final consumer or load, on the other. The process of determining the needs, timing, and requirements for gearbox system additions is known as gearbox planning. The need for transmission could result from:
The Central Electricity Authority (CEA) is charged for creating the National Electricity Plan (NEP) in compliance with the National Electricity Policy and notifying the public of the plan every five years, as per Section 3 of the Electricity Act 2003. CEA has prepared the National Electricity Plan (Volume I) on Generation Planning. The National Electricity Plan Volume II (Transmission) is currently under preparation. It includes the evaluation of the transmission system's development from 2017 to 22, planning for the current plan period of 2022–2027, and a perspective plan for 2027–2032 that takes into account a number of variables, including cross-border power exchange, reactive compensation, and inter-regional transmission links. The system studies for NEP Vol II (Transmission) 2022–2027 have been completed with input from all key stakeholders, including STUs/Electricity Departments, CTUIL, POSOCO, and others, and in consideration of the draught National Electricity Plan (Vol 1: Generation). Finalization is underway for the draught NEP Vol II (Transmission) 2022–27.