The Aggregate Technical and Commercial (AT&C) losses in India are quite high. However, a few private and government owned DISCOS have demonstrated significant improvement in their performance through digital technology adoption. In the 11th Five-Year Plan there was a comprehensible focus to use technology to address these issues. Integrated grid operation which required the normalisation of frequency across all five Regions in the country has been achieved through proactive load management by beneficiaries and despatch discipline by generators. The front image, Fig. 1, and Fig. 2 show respectively, the various renewable energy sources, a thermal power plant connected to the grid, and a nuclear reactor.
To deal with non-technical losses in distribution networks, India undertook a 6-level intervention strategy under the accelerated power development and reforms programme (APDRP). The objective was to:
- make the power distribution sector financially viable
- increase accountability and revenue realization with increased metering
- convert unmetered connections to metered connections, and
- improve billing and collection efficiency.
The 6-level intervention strategy was as follows:
- National Level Interventions: The issues were related to policy matters, legislation, uniform standards, & energy conservation accounting standards.
- State Level Interventions: Formation of State Electricity Regulatory Commissions (SERC), giving out regular tariff orders, providing legislative support to local bodies in management of distribution business, and removal of tariff anomalies.
- State-owned Utility Level Interventions: The issues were restructuring, accountability, commercial accounting, integrated management information system, grid discipline, and time-of-day (TOD) metering.
- Distribution Circle Level Interventions: The issues at this level were related to: (a) Increasing the Income: Increasing the billing, reduction of pilferage, more remunerative pricing of energy, and optimum utilization of physical assets. (b) Reducing the Expenditure: Sourcing of least-cost energy and reducing energy-handling cost.
- Feeder Level Intervention: 11 kV Feeders are the basic source of income to an electricity utility. The issues confronting it are metering and billing, bill collection, abnormal voltage, and ensuring the overall quality of power supply.
- Consumer Level Intervention: The issues at this level are related to mandatory metering, compliance of billing, consumer satisfaction, and energy conservation.
Fig. 1: Thermal power plant
Fig. 2: Nuclear reactor
Availability Based Tariff (ABT)
Five Regional grids exist in India. Some linkages between Regions are also in place. The five Regional grids work at vastly varying frequency levels. Integrated grid operations require the normalization of frequency across all five Regions. The alternative is to insulate each Regional Grid by Back to Back HVDC links. Normalization of frequency requires proactive load management by beneficiaries and dispatch discipline by generators. The Availability Based Tariff (ABT) provides financial incentives to promote grid discipline. Chronic surpluses in some areas and shortages in others can result in sustained functioning of these grids at frequencies which are far beyond the normal band (49.5 to 50.3 Hz). Continued functioning at non-standard frequency results in long-term damages to both generation and end-use equipment leading to higher costs which are borne by the customers in the long term. The ABT induces corrections in the prevailing frequency to bring it within the permissible band by introducing grid discipline. The two-part tariff of the ABT assures that each beneficiary is liable for payment of the fixed cost associated with its share of allocated generation capacity.
The ABT order emphasizes prompt payment of dues. ABT has three parts:
- A fixed charge (FC) payable every month by each beneficiary to the generator for making capacity available for use. The FC varies with the share of a beneficiary in a generator’s capacity.
- An energy charge per kWh of energy supplied as per a pre-committed schedule of supply drawn on a daily basis.
- A charge for Unscheduled Interchange (UI charge) for the supply and consumption of energy in variation from the pre-committed daily schedule. This charge varies inversely with the system frequency prevailing at the time of supply and consumption.
ABT is different from normal procedures to determine generation tariff:
- The ABT procedure does not consider most of the cost drivers like ROE, operational costs, depreciation rate, composition of the Rate Base, capital structure etc.
- ABT is a function not only of the behaviour of a generator but also of the behaviour of the beneficiary. Disciplined beneficiaries and generators stand to gain. Undisciplined beneficiaries and generators stand to lose.
Important features of ABT design
- Electricity tariffs should be two-part comprising of a fixed charge and a separate energy charge.
- Mis-declaration of availability entails severe penalties.
- Incentives are to be earned by generators only where there is a genuine demand for additional energy generation.
- It permits market pricing for the trading of surplus energy by beneficiaries and generators.
Fuel Supply Issues
Planning new Gas-based capacity during 12th Plan (2007-2012) and availability of Gas from domestic sources/RLNG are also to be implemented. Main fuel supply issues are as follows:
- Ways & means to expedite development of coal blocks allocated to CPSUs/ IPPs/ States etc.
- During the 12th plan no Gas-based capacity has been considered due to non-availability of Gas. However, for Green Power Development, there is a need to develop some Gas-based capacity to reduce CO2 emissions.
Latest Technology Options
The development of the power sector has to be in accordance with low-carbon strategy growth. Hence, for efficient technologies for coal-based power generation, impetus to increased adoption of super critical technology is necessary. Since a number of Thermal power projects are facing difficulties in getting required allocation of water round the year, technologies for minimizing consumption of water need to be adopted, including Air cooled condensers and Hybrid Systems for cooling.
Electricity trading with neighbouring countries
Despite low electricity per capita consumption in India, the country is going to achieve surplus electricity generation during the 12th plan (2012 - 2017) period provided its coal production and transport infrastructure is developed adequately. Surplus electricity can be exported to the neighbouring countries in return for natural gas supplies from Pakistan, Bangladesh and Myanmar.
Restructured APDRP (R-APDRP) under 11th Five-Year Plan (2007-2012)
The focus of the Restructured APDRP was on actual, demonstrable performance in terms of loss reduction. State Power Utilities were expected to reduce AT&C (Aggregate Technical and Commercial) losses to 15%. The Utilities were also to achieve the following target of AT&C loss reduction for the Utility as a whole:
- Utilities having AT&C loss above 30%: Reduction by 3% per year
- Utilities having AT&C loss below 30%: Reduction by 1.5% per year
12th Plan (2012-17) Capacity addition
It was proposed to adopt a Low Carbon growth strategy for development of Power Sector during 12th Plan and beyond, as detailed below:-
- Capacity addition from conventional fuel based plants complemented by Renewable Energy based plants to the maximum extent possible.
- In case of Conventional Energy Sources, highest priority to be accorded for setting up of Hydro and Nuclear Power plants. Gas based plants to be accorded higher priority as compared to Coal and Lignite plants to the extent feasible depending on availability of adequate Gas at reasonable price
- Emphasis on efficiency improvement of existing stations, and retirement of old Thermal Power Projects, and less efficient plants, and small size generating units.
- Other measures to be adopted include reduction in T&D losses, and coal quality improvement.
- Efforts to be made to increase Unit Size of Coal based Plants.
- Impetus on increase in adoption of super-critical technology.
A capacity addition of about 1,00,000 MW from conventional power projects is required during the 12th Plan to meet the All-India demand projections. The most probabilistic generation mix for the 12th Plan from conventional energy sources is shown in Table 1:
Gas-based capacity has not been firmed up for the 12th Plan due to uncertainty about availability of Gas for Power Sector. However, efforts are required to be made to plan some Gas based capacity either on indigenous Gas or RLNG. This will help in reducing CO2 emissions per kWh of energy generation.
Since we continue to depend heavily on coal-fired generation, clean coal technologies need to be encouraged to minimize CO2 emissions. Super critical technology will have to be developed in a big way in the 12th & 13th Plan to develop mass indigenous production of Super-Critical Boilers and Turbine-Generators to meet the demand of equipments and to reduce the cost of production.
Transmission system during 12th plan (2012-2017)
Generation capacity addition of about 1, 00,000 MW is envisaged during 12th Plan consisting of Thermal- 76,500 MW, Hydro-20,000 MW and Nuclear- 3,400 MW. The Thermal Generating Stations / UMPPs on imported coal would be near coastal areas and Thermal stations with indigenous coal would be located near Coal pit-heads in Orissa, Chhattisgarh, Jharkhand, Madhya Pradesh, Maharashtra, West Bengal etc. The Hydro Projects would be mainly in Arunachal Pradesh, Sikkim, Uttarakhand, H.P. and J&K, apart from cross-border imports from Bhutan.
As per the Tariff Policy, future procurement of power is going to be increasingly through Tariff based competitive bidding. As a result of liberalization, a large number of Thermal and Hydro generating stations are coming up in Private sector and would participate in bidding.
CEA has evolved a broad contour of Transmission plan for the 12th plan period based on which the individual Transmission schemes would be finalized depending upon the materialization of various Generating projects in real time. Perspective Transmission plan has been evolved for Hydro projects proposed to come up in various river basins in NER, Sikkim, Bhutan, HP, Uttarakhand as well as for large Thermal stations proposed to come up in Chhattisgarh, Orissa, Jharkhand, MP, Andhra Pradesh, Tamil Naidu etc. Transmission planning for Nuclear power projects is to be taken up at appropriate time.
Inter-Regional Transmission System, Substations and Transmission line Requirements during 12th Plan
Some Transmission schemes of early 12th Plan have already been firmed up and remaining Transmission requirements would be arrived at after some clear picture of the projects which are likely to materialize is available. It is anticipated that inter-regional Transmission capacity would be of the order of 57,000 MW by 2015 and about 75,000 MW by end of the 12th Plan. The anticipated requirement of Sub-stations & Transmission lines in the 12th Plan corresponding to 1,00,000 MW capacity additions would be as shown in Table 2.
Electricity distribution during 12th plan
During the 12th Plan it is expected that AT&C loss level of DISCOMs would be much less as compared to the level in 2011 and the economic viability of DISCOMs shall improve.
Intervention of IT & Distribution Automation
Indian Distribution sector is poised for radical transformation in the next decade in the following areas of activities:
- Adoption of Automatic Meter Reading System for HT consumers and High Value Consumers.
- Implementation of SCADA system.
- Consumer Indexing.
- IT based Energy Accounting and Fault Management System.
- Establishment of Modern Consumer Service Centres
- Mapping of Entire Distribution Network through Geographical Information System for enabling Quicker Fault Location and Speedy Resolution of Faults
- Use of Energy Efficient Distribution Transformers.
Enhancement of Manufacturing Capacity for Main Plant Equipment Commensurate with Planned Capacity Addition
In view of large capacity addition required during the coming few plans, there is an urgent need for more indigenous manufacturers of Thermal Main Plant, particularly with capability to manufacture super-critical technology based units in the country to meet the enhanced requirement. There is a need to bring down the cost of super-critical Boilers and Turbine-Generators which is possible with indigenization of manufacturing facilities. There is also a need for the manufacturers of Main Plant equipment to play an active role in the development of ancillaries units and vendors commensurate with their own manufacturing capacity and to ensure that deliveries are sequential and in time.
Development of Renewable Energy Sources Including Solar Technology
The renewable energy sources are shown in the front image of the paper. According to the Electricity Act - 2003 and the Tariff Policy, the appropriate Electricity Regulatory Commissions have to specify the minimum percentage of energy to be procured by Distribution licensees from Renewable sources. Unused Land at Thermal power plants could be utilized for solar installations to give a boost to solar power. Co-generation through indigenous Gas with combined cooling also needs to be encouraged for efficient use of Gas.
Development of Solar Power
A National Solar Mission has been launched under the National Action Plan for Climate Change (NAPCC) to significantly increase the share of solar energy in the total energy mix while recognizing the need to expand the scope of other renewable and non-fossil options such as Nuclear, Wind Energy and Biomass. The ingress of solar technology for energy use has been slow due to a number of factors, predominantly the high capital cost and large land requirement for solar installations. A further constraint has been its availability only during the day for energy use, thereby requiring additional high cost for storage systems.
Plans for Development of Solar Power
The 12th five-year Plan (2012-2017) will involve scale up of various validated applications (primarily grid-tied applications), continued rollout of rural electrification business models and commercial deployment of Solar Thermal Plants. This phase is also likely to see pilot deployment of next generation technologies like dish-sterling, concentrated solar power, thin film applications and storage systems. Solar lights and solar water heaters are to be promoted in the market mode without capital subsidies. The Target of the 12th plan is to achieve an installed capacity of about 6000 - 7000 MW by 2017.
Development of Wind Power
India's electricity sector is amongst the world's most active players in renewable energy utilization, especially wind energy. http://en.wikipedia.org/wiki/Electricity_sector_in_India - cite_note-13 Table 3shows the renewable energy installed capacity (grid-connected and off-grid) in India (as of 31 December 2012).
India plans to add about 30 GW of installed electricity generation capacity, based on renewal energy technologies, by 2017. http://en.wikipedia.org/wiki/Electricity_sector_in_India - cite_note-pib1211-61 India has the fifth largest installed wind power capacity in the world. In 2010, wind power accounted for 6% of India's total installed power capacity, and 1.6% of the country's power output.
Future scenario
A capacity addition requirement of about 1,02,000 MW (compared to 1,00,000 MW for the 12th Plan) has been assessed for the 13th Plan (2017-2022). In addition 14,500 MW Hydro power is also expected to be imported from Neighbouring countries.
Development of solar power
13th Plan (2017-2022) will be focused on very rapid scale-up across all validated applications with minimal or no subsidies, as achievement of Tariff parity with conventional grid power is expected. 13th Plan is also likely to see commercialization of storage technologies and indigenously developed PV/Solar thermal technologies. Target of 13th Plan will be to rapidly increase the installed capacity to 20 GW by 2020.
Smart Grid
Concerns about climate change, energy security and dwindling fossil fuel reserves are stimulating ever increasing interest in the generation, distribution and management of renewable energy. While a lot of attention has been devoted to generation technologies, an equally important challenge is the integration of energy extracted from renewable resources into existing electricity distribution and transmission systems. Renewable energy resources like wind and solar energy are often spatially distributed and inherently variable, necessitating the use of computing techniques to predict levels of supply and demand, coordinate electricity distribution, and manage the operations of energy storage facilities.
A key element of the solution to this problem is the concept of the “Smart Grid”. A smart grid is broadly perceived as an evolved form of the traditional electricity grid where advanced techniques such as Information and Communication Technology (ICT) are used extensively to detect, predict and intelligently respond to events that may affect the supply of electricity. A smart grid generates a large amount of data from its various components, examples of which include renewable energy generators and smart meters; the potential value of this data is huge but exploiting this value is almost impossible without the use of proper analytics. With the application of systematic analytics on the smart grid’s data, its goal of better economy, efficiency, reliability, and security can be achieved. Therefore, data analytics is an essential tool that can help to imbue the smart grid with “smartness”.
The key targets and highlights in the smart grid roadmap for India are shown in Table 4 herein.
C S Indulkar is Retired as Professor and Head of Electrical Engineering from IIT Delhi, he has authored a number of technical papers in various refereed journals, including IEEE Transactions and IET Proceedings. He has also been a reviewer of papers for the above journals and for several other International Journals of Electrical Engineering.
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