The Grid: Reliability& Resilience in India

BACKGROUND:

Power Grid has different names – power distribution grid, electrical grid and national grid, and is an interconnection network for reaching electricity from the producers to consumers.  Understandably, the historical development would be different in different countries depending upon the state of development.  India, started with the diesel power station of 2 MW in Delhi (1905), a private plant set up by John Fleming who got the licence under the provisions of Indian Electricity act 1903.  Later on this got transformed into Delhi Electric Supply and Traction Company.  The first hydroelectric was erected at Sivasamudram in Mysore, Karnataka in 1902.

The first legislation ‘Indian Electricity Act 1987’ was repealed and replaced by ‘Indian Electricity Act, 1903’ to deal with broad lines applicable to the country as a whole.  Since its inception, power grid has undergone transformation through Electricity Supply Act (ESA), 1948 facilitating establishment of State Electricity Boards (SEBs) and Central Electricity Authority (CEA).  While it initially began as private sector, the Industrial Policy Resolution entrusted generation and distribution exclusively for Public Sector.  Regional Electricity Boards facilitated integrated operation to encourage States to build infrastructure for exchange.   Rural Electrification Corporation (REC) was set up in 1969 followed by National Hydroelectric Power Corporation (NHPC) and National Thermal Power Corporation (NTPC) in 1975.  Power Finance Corporation (PFC) in 1986 was to assist new capacities and finally, Power Grid Corporation of India Ltd. (PGCIL) saw its emergence in 1989.

POWER GRID CORPORATION OF INDIA LIMITED (POWERGRID):

National Power Transmission Corporation Limited was formed in 1989 under the Companies Act, 1956 with responsibility of planning, executing, owning, operating and maintaining high voltage transmission systems in the country.  However, the name was changed in 1992 to Power Grid Corporation of India Limited (POWERGRID), headquartered in Gurgaon, Haryana, India.

POWERGRID operates businesses like, power system management, Telecom, International business, Domestic Consultancy, Smart Grid, Human Resource Development, Technology Development (R&D) and EV charging infrastructure.  The power system management implies operation & maintenance of the Transmission systems.

The Indian Power system has five regional grids and an integration of them led to National Grid which encompasses asynchronous HVDC back-to-back inter-regional links facilitating limited exchange of regulated power which graduated into high capacity synchronous links.  Currently, the country has a total inter-regional transmission capacity of 1,12,250 MW which is to be enhanced to 1,18,740 MW by 2022.  Synchronization of regional grids helps optimal utilization of scarce natural resources by transfer of power from Resource Centric Regions to load centric regions.  This will further establish vibrant electricity market facilitating trading of power across regions.

CHALLENGES ON RELIABILITY

Distribution Company (DISCOM) carried load shedding details - frequent power outages, daily or weekly load shedding, and pre-defined intervals for planned power supply cut off.  Over a period of time and when peak demand deficit reduced to 0.8% from 16.6% in 2007, the scenario changed due to private sector investment in power generation (mostly coal).   However, the frequency of planned outages/interruptions that consumers had to face did not change despite India was declared a power-surplus nation.  Though electricity supply was more in line with demand, the investments in distribution infrastructure fell short casting a doubt on reliability of the Grid.  This warranted introspection on resolving reliability issues and analyse impact of improved reliability.

Simple definition of reliability is ‘the electricity you need, when you need it’ which means that end-use consumption should not be affected either by lack of generation or by disruptions on distribution network and not at the cost of societal cost-benefit perspective.  Policy makers determined minimum requirements for a reliable grid – to be met by generation and transmission utilities and system operators and secondly, distribution utilities to ensure desired level of reliability at a cost the society were willing to pay.

Ministry of Power (MoP) in 2005 issued National Electricity Policy with a vision for reliability – creating adequate reserve capacity margins and a spinning a reserve of at least 5% at the national level for not only grid security but reliable power supply.  Standards for reliability and quality power by distribution utilities and even consumer interest protection were clearly defined in the policy.  Indian Electricity Grid Code Regulations 2010 and amendments gave way to plan, develop, maintain and operate power systems in the most secure, reliable, economic and efficient manner.  Discoms adopted Standards of performance regulations as notified by state electricity regulatory commissions (SERCs) – average interruption frequency index, average interruption duration index and even time taken for either restoration or new connection.  In addition, Ministry of Power issued Electricity Right of Power Consumers Rules 2020 to ensure minimum standard of service for electricity supply to consumers.  While these directives did improve reliability on bulk power system, it did not reflect on distribution network.   Global Competitiveness Report of 2019 of the World Bank cites India at 108th place out of 141 countries.

Regulatory will to penalise Discoms for non-compliance with standards so clearly defined could perhaps be one of main reasons for noncompliance and even public pressure.  Secondly, expectations that Discoms will actually improve reliability for all consumers seem low.  Above all, it the financial health of Discoms that prevents them from their set targets.  One of the ways is aimed at rooftop PV along with storage on select feeders where reliability is poor. More importantly, cost effective, clean and efficient approach for reliability improvement could be hoped through non-wire alternatives – Renewables.  It is also worth knowing the other aspects of reliability as under:

Underground vs Overhead:

Grid reliability, safety and economic aspects warrant increased attention on the choice of underground or overhead cables.  Electrical distribution substations are meant to step-down transmission voltage levels which in India is 33 kV/11kV.  However, voltages at utility delivery points may require further step-down either by utility transformers or customer owned and operated transformers to 400V (3 phase) or 230 V (Single phase). Whether it overhead or underground cable selection is crucial to ensure desired level of reliability with a mind on cost effectiveness.  Power cables (consists of conductor, insulation, beading, armouring and outer sheath) are an assembly of one or more individually insulated electrical conductors held together with an overall sheath.

Outages:

There are many applications for outage management covering event scenarios, real-time grid monitoring and effective use of human resource.  Power outages (from 2 – 8 hours) seem to have been the worst in India this year in over six years.  India, being the third largest energy consuming country faced a serious crisis of coal reserves in several states running out.  Against a commitment of 175 GW renewables by 2022, India achieved just around 44 GW till July 2022.  However, power demand has increased from 106..6 billion units (BU) to 132 BU in 2022.  This may be because of lack of co-ordination among coal, railway and power ministries with each claiming that they are not responsible for the current chaos.

Vegetation Management:

Vegetation management is indeed crucial for efficient grid management to ensure reliability. This tough task has been now simplified with advanced analytics; Satellite, local circuit inspection and even crowd sourcing are key elements that deserve serious attention.  Drones would supplement the above more effectively

Non-wires alternatives are indeed evaluated world over to overcome local challenges of grid resilience, flexibility and equity.  Considering that the renewables have become attractive now not only cost wise but even technology wise, distribution utilities have to gear up to the new opportunities to resolve reliability aspect of electricity supply.  One of the recent surveys concluded that poor reliability discourages investment in electricity consuming appliances by investment in Electricity producing appliances.

MOVING TOWARDS RESILIENCE

It attracts sustained efforts if India wishes to achieve generating capacity target of 1.2 terawatts by 2047.  This in fact is the demand to meet economic growth and Sustainable Development Goal 7 (SDG) providing universal electricity access.  This would be in combination of reducing greenhouse gas emissions as well.

Many of us are aware of the developments at the annual conferences of United Nations Framework Convention for Climate Change (UNFCCC).  Global investments on clean energy technologies increased substantially between 2014 & 2019 and are estimated to spill over US$1 trillion by 2030.  Even COP26 emphasised the need to reduce cost of low-emission technologies and facilitating economy-wide green transition.  This emphasis extends even to grids in moving toward ‘Smart Power Grids’.

The National Electricity Policy of 2021 in India did spell out a paradigm shift in its overall approach – Clean and sustainable generation, Adequate and efficient transmission system, Revitalize Distribution Companies (DISCOMS), efficient market for electricity, Reliable and quality power of specified standard in an efficient manner, move towards light-touch regulation and promote manufacturing of goods and services in India (Generation, Transmission and Distribution sectors).  India responsible for 6.65% of total global carbon is ranked fourth next to China according to World Resources Institute (WRI) in 2017. India has committed to increase its cumulative installed non-fossil-fuel-based electricity to 40% by 2030. Further, it has to achieve 100% national electrification through grid connections or mini and off-grid systems by 2030. India’s commitments at COP26 seem encouraging – a. net zero emission by 2070, b. 500 MW non-fossil fuel capacity, c. 50% requirements from RE by 2030, d. emission reduction by 1 BT from now till 2030 and e. reduce total carbon intensity by 45% by 2030. The technology solution inter-relationship seem attractive as indicated for efficiency and emission:

There are a few interesting facts about India’ power outlook – i. per capita emissions are 60% less than global average despite emission intensive energy generation; ii. Solaris slated to dominate power generation in the next three decades; iii. It would overtake EU as world’s third biggest energy consumer; iv. Energy consumption would double; v. Fossil fuels continue to play significant role at 51% by 2030.  

As per NITI Aayog, share of coal, natural gas, renewable, hydro and nuclear would be 30%, 6%, 50%, 11% and 3% respectively. Greenhouse gas emission reduction would be achieved mostly through solar and wind. Indian power grid demands adequate energy storage options as incorporation of stochastic distributed RE resources and Electric Vehicle (EV) infrastructure of varying capacities would usher instabilities in the power grid which need to be plugged with Electrical Energy Storage (EES) systems. The rise would be from 57 GWh in 2022 to 341 GWh in 2032 – accordingly EES requirement would be grid support. (2022/2032) (10%/13%), Telecom (14%/5%), UPS & data centres (49%/14% and Electric mobility (18%/68%) respectivelyThe capital requirement for EC based energy storage capacity till 2047 would be about US$ 200 billion in the PHS and US$80 billion in the electrochemical based systems.

The National e-mobility targets pushed EV penetration due to domestic battery manufacturing capabilities and grid charging infrastructure.  Many States in India are gearing up to the demand of EV charging infrastructure through adequate policies with an attractive 5% GST. The grid supported EV transformation facilitates cumulative crude oil import savings. The short, medium and long term EV charging infrastructure further helps demand on renewable generation, smart meters, demand energy efficiency and increased market.

The high voltage power transmission handles about 7,50,000 MVA spanning around 3,70,000 circuit kilometres.  Despite frequency response characteristics (FRC) of the grid have improved from 6 to 9GW/Hz, stability and reliability seem lower than comparable grid sizes where FRC is 20GW/Hc. This warrants modern technologies and improved governance for grid reliability and reduction in T&D losses.  In fact, smart grid presents several advantages –

The Phasor Measurement Units (PMU) helps data for wide area real-time grid visibility to detect oscillation, frequency stability monitoring, voltage stability, disturbance, resource integration, state estimation, congestion management, islanding and rapid restoration which are pretty vital for Grid reliability improvement. The availability of high frequency grid information helps stability improvements of both mini and micro-grid.  Advanced Metering Infrastructure (AMI) is underway for 38 million smart meters which would be the first step in smart grid realization which could take India on par with developed economies.  Information and Communication Technologies (ICT) need be enhanced towards effective implementation of Smart Grid.

India has a challenging weather pattern clubbed with frequent natural calamities.  The recent calamities like earthquake and cyclones have had their impact on power grid and therefore demand a special care.  The power grid needs to gear up with emergency plans with update data on availability of manpower and material resources in addition to assistance among all power sector utilities.  Standard Operating Procedure (SOP), Logistics and co-ordination, Post Disaster Response and Recovery and Future initiatives for Grid reliance are an absolute necessity. High resolution information and numerical weather prediction models, optimal investment for robust buildings and grid resilience, cross sector collaboration for crisis management are a few issues that need be addressed.

Climate change poses challenges to both man-made and natural ecosystems as the frequency seem to have increased over a period of time.  In fact, India jumped nine places in climate vulnerability ranking and is believed to be fifth most climate vulnerable country.  Despite several international commitments over the years, we seem to have failed restricting the earth’s temperature.  Added to this several associated events seem to be springing up year after year.  India alone has witnessed more than 478 extreme events since 1970 and an acceleration of their frequency after 2005.  It is therefore time to deviate from the focussed attention on carbon dioxide increase to an holistic approach on atmospheric chemistry for a better understanding of climate change

CONCLUSION:

Grid reliability would be more challenging in view of not only growing power demand including digitalization but even renewables accounting for a greater share of power generation.  In addition, climate change may induce many unwanted weather complications as we move ahead without proper address of this global issue.