National Grid (India)

{{Short description|Electricity transmission network in India}}

{{Use dmy dates|date=September 2023}}

File:Regional power grids in India.svg

The National Grid is the high-voltage electricity transmission network in India, connecting power stations and major substations and ensuring that electricity generated anywhere in India can be used to satisfy demand elsewhere.{{cite web |url=http://www.iexindia.com/bidareas.aspx?id=31&mid=2 |title=Areas of national grid |access-date=19 October 2016 |archive-date=20 October 2016 |archive-url=https://web.archive.org/web/20161020014607/http://iexindia.com/bidareas.aspx?id=31&mid=2 |url-status=dead }} The National Grid is owned, and maintained by state-owned Power Grid Corporation of India and operated by state-owned Power System Operation Corporation. It is one of the largest operational synchronous grids in the world with 417.68 GW of installed power generation capacity as of 31 May 2023. {{cite web|url=http://cea.nic.in/reports/monthly/installedcapacity/2020/installed_capacity-06.pdf|title=All India Installed Capacity of Utility Power Stations |access-date=10 July 2020}}

India's grid is connected as a wide area synchronous grid nominally running at 50 Hz. The permissible range of the frequency band is 49.5-50.5 Hz, effective 17 September 2012. The Union Government regulates grid frequency by requiring States to pay more when they draw power at low frequencies.{{cite web|last1=Bhaskar|first1=Utpal|title=CERC plans to further narrow frequency band for national grid|url=http://www.livemint.com/Industry/3HIYmLsbcM47fsaCUyK7DI/CERC-plans-to-further-narrow-frequency-band-for-national-gri.html|website=Livemint|date=30 July 2013 |access-date=2 December 2016}} There are also synchronous interconnections to Bhutan, and asynchronous links with Bangladesh, Myanmar, and Nepal.{{cite web|title=Grid Security – Need For Tightening of Frequency Band & Other Measures|url=http://www.cercind.gov.in/2011/Whats-New/AGENDA_NOTE_FOR_15TH_CAC_MEETINGHI.pdf|website= Central Electricity Regulatory Commission|access-date=2 December 2016}} An undersea interconnection to Sri Lanka (India–Sri Lanka HVDC Interconnection) has also been proposed. A proposed interconnection between Myanmar and Thailand would facilitate the creation of a power pool and enable trading among all BIMSTEC nations.{{cite web|title=BIMSTEC needs a 'power tool'; here's why it is time for a green energy revolution|url=http://www.financialexpress.com/opinion/bimstec-needs-a-power-tool-heres-why-it-is-time-for-a-green-energy-revolution/494732/|website=The Financial Express|access-date=27 May 2017|date=3 January 2017}}

History

India began utilizing grid management on a regional basis in the 1960s. Individual State grids were interconnected to form 5 regional grids covering mainland India. The grids were the Northern, Eastern, Western, North Eastern and Southern Grids. These regional links were established to enable transmission of surplus electricity between States in each region. In the 1990s, the Indian government began planning for a national grid. Regional grids were initially interconnected by asynchronous HVDC back-to-back links facilitating limited exchange of regulated power. The links were subsequently upgraded to high capacity synchronous links.

The first interconnection of regional grids was established in October 1991 when the North Eastern and Eastern grids were interconnected. The Western Grid was interconnected with the aforementioned grids in March 2003. The Northern grid was also interconnected in August 2006, forming a Central Grid synchronously connected operating at one frequency. The sole remaining regional grid, the Southern Grid, was synchronously interconnected to the Central Grid on 31 December 2013 with the commissioning of the 765 kV Raichur-Solapur transmission line, thereby establishing the National Grid.{{Cite news|url=http://timesofindia.indiatimes.com/india/All-India-Power-Engineers-Federation-Indian-power-system/articleshow/28294988.cms|title=Indian power system becomes largest operating synchronous grid in the world|newspaper=The Times of India|access-date=2 December 2016}}{{cite web|title=One Nation-One Grid|url=http://www.powergridindia.com/_layouts/PowerGrid/User/ContentPage.aspx?PId=78&LangID=english|website=Power Grid Corporation of India|access-date=2 December 2016}}

Territories outside the grid

The union territories of Andaman and Nicobar Islands and Lakshadweep are not connected to the National Grid. Both territories are archipelagos located far away from the mainland.{{cite web|title=Renewable Energy|url=http://www.powerlak.gov.in/eBCMs/eBCMsConsumerPortal/frmRenewable.aspx|website=Department of Electricity, UT of Lakshadweep|access-date=2 December 2016|url-status=dead|archive-url=https://web.archive.org/web/20160709204225/http://www.powerlak.gov.in/eBCMs/eBCMsConsumerPortal/frmRenewable.aspx|archive-date=9 July 2016}} Due to the geography and topography of these islands, including separation by sea over great distances, there is no single power grid for all the electrified islands in the archipelago. The power generation and distribution systems of these territories is served by standalone systems, with each electrified island in the archipelago having its own generation and distribution system. Power stations cater independently to the power requirements of an area.{{cite web|title=Power Department|url=http://www.andaman.gov.in/power|website=Andaman and Nicobar Administration|access-date=2 December 2016}}{{cite web|title=Power for All - Andaman and Nicobar|url=http://powermin.nic.in/sites/default/files/uploads/joint_initiative_of_govt_of_india_and_andman_nicobar.pdf|website=Ministry of Power|access-date=2 December 2016|archive-date=13 February 2020|archive-url=https://web.archive.org/web/20200213022507/https://powermin.nic.in/sites/default/files/uploads/joint_initiative_of_govt_of_india_and_andman_nicobar.pdf|url-status=dead}} The Electricity Department of Andaman and Nicobar (EDA&N) and the Lakshadweep Electricity Department (LED) are responsible for generation, transmission and distribution systems in these territories.{{cite web|title=DEPARTMENT AT A GLANCE|url=http://electricity.and.nic.in/|website=electricity.and.nic.in|access-date=2 December 2016|archive-date=10 August 2020|archive-url=https://web.archive.org/web/20200810111009/http://electricity.and.nic.in/|url-status=dead}}

Inter regional transmission capacity

The inter regional total transmission capacity (TTC) is 105,050 MW as on 30 June 2021.{{Cite news|url=http://powermin.nic.in/sites/default/files/uploads/IRTC_English_May_2017.pdf|title=Inter Regional Transmission Capacity|access-date=2 July 2017}}{{Dead link|date=September 2023 |bot=InternetArchiveBot |fix-attempted=yes }} However the available transmission capacity (ATC) on daily basis is not exceeding 35% of TTC and the actual usage is around 25%.{{Cite news|url=https://posoco.in/market/monthly-atc-inter-regional/|title=Monthly ATC Inter Regional |access-date=2 July 2017}}{{Cite news|url=https://posoco.in/reports/daily-reports/daily-reports-2017-18/|title= NLDC Daily Reports – 2017-18 |access-date=2 July 2017}} Due to inter regional transmission constraints, the cost of power purchases by every region in Power Exchanges is not always equal.{{Cite news|url=http://www.iexindia.com/marketdata/areaprice.aspx|title= IEX Area Prices |access-date=2 July 2017}} MoP has introduced a policy for nationwide single merit order power purchases from Power exchanges to avoid costly power purchases by the Discoms.{{Cite news|url=http://meritindia.in/|title=Merit Order Despatch of Electricity|access-date=12 July 2017|archive-date=15 June 2021|archive-url=https://web.archive.org/web/20210615010502/http://meritindia.in/|url-status=dead}}

See also

References

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