Chapter 4. Electricity Supply and Transmission System. In India, there are five regions namely, Northern Region, North Eastern Region,

Transcription

1 44 Chapter 4 Electricity Supply and Transmission System In India, there are five regions namely, Northern Region, North Eastern Region, Eastern Region, Southern Region, and Western Region. Each region has its own interconnected transmission system known as regional grid. The electricity services invite jurisdiction of central and state governments and are included in the concurrent list of constitution of India (Singh 2006). The erstwhile Electricity Supply (Act) 1948 led to the establishment of State Electricity Boards (SEBs) to achieve public goals and retained monopoly status in power sector. In 1975, the Central government set up two power generation companies i.e. National Thermal Power Corporation Limited (NTPC) and National Hydroelectric Power Corporation Limited (NHPC). In 1991, the Government of India formulated a policy to encourage greater investment by private enterprises in electricity sector (Balachandra, 2004). Since the independence of India, the power generation capacity and the transmission and distribution network are continuously growing, but still now 44.2% of households have no access to electricity and consumers are facing severe power shortages of 7% with peak shortages of 11% (Indian Census Report 2001). The subsidized categories are increasing with the expansion of electricity network and rural electrification drive. The financial health of power utilities is deteriorating due to lack of expenditure prudence and skewed tariff structure. The industrial and commercial consumers have started to move towards installing their own power generation capacities for getting economy, quality, and reliability in electricity supply. Today, most of the State Electricity Boards (SEBs) are suffering with more than 30% AT&C losses and are not capable to pay their dues of coal and oil, rail transportation, and other expenditures. The SEBs are

2 45 performing not well in terms of their technical and financial performance and even they rely upon central power utilities in adding their substantial generation capacities. However, the central power utilities are performing well in terms of PLF which is 82.8% against 69.9% of state power utilities. Policy and Regulatory Developments The Private Power Policy (1991) opened up the power generation path for private players and provided various incentives to attract them. In 1995, the Mega Power Policy40 is introduced to provide additional incentives for mega power plants i.e. plant with capacity more than 1000 MW. The policy also provided fiscal initiatives including tax holidays for 10 years along with exemption of customs duty on the imported equipments. Further, the Government of India decided to improve the performance of power sector and introduced first time the power reforms in Orissa with the enactment of Orissa Electricity Reforms Act 1995 by which the electricity business was divided into three separate activities i.e. Generation, Transmission, and Distribution41. Since 1998, the Central Electricity Regulatory Commission (CERC) is regulating the tariffs of generation and transmission utilities which are controlled by the Central government. The State Electricity Regulatory Commissions (SERCs) adopt a transparent procedure for tariff filing, its review and passing orders to fix the transmission and distribution tariffs for the consumers. Further, the tariff determination process have become more transparent and participative as the electricity utilities have started to make public announcement of tariff filings and to seek public comments by holding public hearings within the State. Now-a-days, the SERCs ensure the proper 40 The Mega Power Policy is retrieved from 41 This information is retrieved from the website of planning commission i.e. planningcommission.gov.in/plans/stateplan/sdr_orissa/sdr_orich13.doc

3 46 alleviation of consumer concerns related to quality improvements. The Electricity Act 2003 which was replaced with erstwhile three Acts namely Indian Electricity Act 1910, Electricity (Supply) Act 1948, and Electricity Regulatory Commissions Act 1998; is regulating the entire power sector42. It provides various provisions to end the monopoly of vertically integrated SEBs by splitting them into three functional divisions i.e. generation, transmission and distribution. It also enables the competition in bulk power market through de-licensing of thermal generation, open access of transmission, and recognition of trading activities. The open access in distribution function encourages competition in retail electricity supply under the regulations of respective SERCs. The act puts emphasis for greater need of distribution reforms for improving the financial health of the sector. Further, there is National Electricity Policy 2005 which was passed to resolve the problems that plague the power sector43. However, it has remained unsuccessful in bringing the desirable changes due to lack of spirit in its implementation. But the policy presents the directions and sets ambitious goals for improving the Indian power sector. The policy tried to ensure accessibility of electricity to all households, presented guidelines to supply reliable and quality power of specified standards efficiently, and also emphasized for financial turnaround and commercial viability of power sector. Electricity Supply and Transmission System in Haryana The Haryana State Electricity Board (HSEB) was constituted on 3rd May, 1967 and started to incur losses from The main reasons identified for the losses were un-remunerative tariff, electricity supply at subsidized rates, low plant load 42 The Electricity Act, 2003 is retrieved from 43 The National Electricity Policy is retrieved from

4 47 factor (PLF) in thermal power stations, and excessive transmission and distribution (T&D) losses. In 1993, the government decided to restructure the board and appointed consultants for Power Sector Restructuring Project Study. The consultants (1995) outlined a reform programme including creation of independent power regulatory body, segregation of power generation, transmission and distribution functions, private sector s participation, financial restructuring, tariff rationalization, and reduction in T&D losses. After four years, the Haryana Electricity Reform Bill (1997) is enacted on the basis of consultants reports and the Haryana Electricity Reform Act, 1997 provided provisions for constituting Haryana Electricity Regulation Commission (HERC), restructuring of electricity sector in Haryana Power Utilities separately responsible for generation, transmission, and distribution, and creation of avenues for participation of private sector entrepreneurs in electricity industry. The Act also provided to take measures conducive to the development and management of electricity industry in an efficient, economical and competitive manner. The erstwhile HSEB was restructured due to various reasons including lack of efficiency in generation, higher transmission losses, ineffective performance in distribution, and political interference in internal functioning of the board. At present, Haryana power sector includes four wholly state-owned corporations i.e. HPGCL, HVPNL, UHBVNL, and DHBVNL responsible to meet the demands of consumers. These utilities are regulated by HERC, an independent regulatory body working under the administrative control of Department of Power. It is required to strengthen the utilities in technical and financial terms as it is assumed that once the HPUs become financially viable, the power sector can be made a generator of net resources for the state. The power sector can be made capable of arranging its

5 48 investment requirements on its own financial strength44. Diagram 3.1 Components of Electricity Supply and Transmission System The Electricity Supply and Transmission System may be defined as an orderly group of interdependent components i.e. generation, transmission, and distribution; linked together according to a plan to achieve the goal of meeting electricity needs of the consumers in an efficient and effective manner. Diagram 3.1 shows the components of the system which can be explained as under: a. Haryana Power Generation Corporation Limited (HPGCL) The electricity is generated either with the help of spinning water-wheels or steam-turbines. At Haryana s thermal power stations, turbines consume the fuel (coal and oil), extract thermal energy from pressurized steam, and convert the energy into rotary motion. Large generators generate three-phased Alternating Current (AC) which is transmitted to various substations located over a large distance covering all districts of Haryana. At substations, the transformers transform the current i.e. Alternating Current (AC) to Direct Current (DC) and DC to AC for meeting the transmission and distribution functions. 44 The data can be retrieved at

6 49 Diagram 3.2: Three phases plus a neutral wire in power plants. There are four wires coming out of every power plant: the three phases plus a neutral or ground wire which remain common to the three. Diagram 3.2 shows the three phases and the ground. The electricity is transmitted and distributed to the destination points through power distribution grids. The AC is converted into DC for transmission purposes and then converted back to AC for retail distribution. Such conversions involve extra steps over generated power and these steps are performed at transmission and distribution substations. At the time of restructuring HSEB, the business of power generation was transferred to HPGCL on 17th March The utility s main objective is to generate electricity from the existing generating stations and sell it exclusively to HVPNL, the transmission utility of Haryana. HPGCL is also entrusted for setting up new power projects apart from undertaking Operation and Maintenance (O&M) of the power plants. It generates revenues by trading of generated power including procurement of electricity on long and short term basis and purchasing it from power producers as well as traders, by signing Power Purchase Agreements (PPAs). The utility has installed capacity of MW as given in table 1.1. The HPGCL is working on ambitious plans of adding sufficient generating capacity to bridge the gap between demand and supply. Out of MW, the 3020 MW capacity is added during August 2010 to April The corporation is also planning to add more capacities in future including 1050 MW gas based project at Faridabad, 660 MW thermal based project at Yamuna Nagar as an extension to

7 50 2x300 MW DCRTPP, and 2800 MW nuclear power based projects near Fatehabad (Hissar). However, the efficiencies depend upon the functioning of the units. Table 1.1 Total Installed Generation Capacity of HPGCL Power Stations as on Name of Power Station Capacity in MW45 1. Panipat Thermal Power Station Unit I MW 2. Panipat Thermal Power Station Unit II, III, IV 110x3 = 330 MW 3. Panipat Thermal Power Station Unit V, VI 210x2 = 420 MW 4. Panipat Thermal Power Station Unit VII, VIII 250x2 = 500 MW 5. Deenbandhu Chhotu Ram Thermal Power 300x2 = 600 MW Sr. No. Project (DCRTPP), Yamuna Nagar Unit I and II 6. Rajiv Ghandhi Thermal Power Project, Khedar, 600x2 = 1200 MW Hisar 7. Indra Gandhi Super Thermal Power Project, 250x2 = 500 MW Jhajjar 8. Mahatama Gandhi Super Thermal Power 660x2 = 1320 MW Project, Jhajjar 9. Western Yamuna Canal Hydro Project, Yamuna 8x6 = 48 MW & Nagar 7.2x2 = 14.4 MW 10. Micro Hydel Project station, Kakroi 0.3 MW Total MW Source: Generation statistics given b. on HPGCL s website i.e. Haryana Vidyut Prasaran Nigam Limited (HVPNL) The HVPNL handles the activities related to purchase of power and its wheeling 45 MW stands for Mega Watts i.e. one million watts, a unit for measuring electrical power.

8 51 for bulk distribution. After its incorporation on 19th August 1997, this utility is entrusted for transmission & bulk supply of electricity. Transmission is the second component or layer of electricity supply and transmission system which may be described as a highway over which the generated power flows. The system requires constant, second by second, balancing of supply, demand, and transmission capability. The transmission as a function is primarily responsible for maintaining the delicate balance between demand and supply. A transmission system can be defined as the system having design voltage of 66 kv and higher that is used for the transmission of electricity. It includes transmission lines, bays/equipment, substations, plant, apparatus and meters necessary for carrying out the transmission activity. The transmission department constructs, operates and maintains transmission lines and substations for transmission of bulk power generated at various power generation stations as well as the state s share of power received from the Central government s power plants through this network. The network is managed by transmission circle offices and divisional offices. The three-phased AC power generated at power plant enters transmission substations where large transformers convert AC voltage (which is at the thousands of volts level) up to extremely high voltages for long-distance transmission. Stepup transmission substations receive electricity from generating utility and transmission buses wheels the power over the transmission lines. The circuit breakers of substations are used to switch the generation and transmission circuits, as required in emergencies either at the time of shutting down the power or when it is required to redirect the power. While distributing power, the distribution substations change the voltage to lower levels. In the system, the operations are managed by the control area operators to balance the electricity demands with

9 52 electricity generation continuously and also to predict the required future electricity. The operators keep the flow of electricity within specific limits to ensure reliability and prevent the system from being fail. The transmission system has two primary objectives: (i) the security and reliability of the system and (ii) the economy of the system. The operators are responsible for achieving an efficient, economical, and reliable power supply over the system. HVPNL also have ownership interest in two projects: BBMB and Indraprasth Power Station (Delhi Vidyut Board). The main objectives of Haryana Vidyut Prasaran Nigam Limited (HVPNL)46 are: (i) Planning, design, construction, and erection of transmission lines, (ii) Maintenance of sub-stations with voltage levels of 66KV & above, and (iii) Wheeling of power in accordance with the policies, guidelines laid down by Haryana government or Haryana Electricity Regularity Commission (HERC). The HVPNL monitors and maintains grid discipline, resolves grid issues, resources funds for proper implementations of plans, augments and strengthen the power transmission capability, and acts as state transmission utility to ensure adequate, safe and economical transmission of electricity with regard to quality, availability and reliability of services. The utility earns revenues from wheeling and sale of power. Wheeling is the act of providing the service of transporting electric power over transmission lines. The transmission lines move electric power between generating facilities and substations, usually in or near population centers. From substations, electricity power is sent to users over a distribution network. The utility also earns revenues by selling the electricity power with the help of providing open access facility directly to the consumers. A transmission line might move power a few miles or 46 The information on HVPNL is available at

10 53 hundreds of miles. The HPGCL has a connection to the network or grid for transmitting generated power and it pays HVPNL for wheeling of electricity power over the network, based on how much power is being moved and how congested the line is. c. Uttar Haryana Bijli Vitran Nigam Limited (UHBVNL) and Dakshin Haryana Bijli Vitran Nigam Limited (DHBVNL) These two utilities are responsible for distribution and retail supply of electricity in their concerned regions. The UHBVNL undertakes business in northern parts of Haryana i.e. Panchkula, Ambala, Yamunanagar, Kurukshetra, Kaithal, Karnal, Panipat, Sonepat, Rohtak, Jhajjar and Jind districts and the DHBVNL covers distribution function in South Zone including Hisar, Fatehabad, Bhiwani, Sirsa, Faridabad, Gurgaon, Mewat, Rewari, and Narnaul districts. HVPNL which transferred the generated electricity in bulk over a long distance at high voltage of 132 KV and above, that electricity is distributed for retail supply by the UHBVNL and DHBVNL s distribution system which consists mainly of cables, service lines and overhead lines, electrical plant and meters having design voltage of 33 kv and below. The distribution function is the most critical function of the system in which the electricity is passed to huge number of consumers through Circuit Kilometers47 (ckm) of HT lines and LT lines with the help of transformers. The utilities supply electricity to residential areas, commercial complexes, streetlights, water works, agriculture, and the industries. 47 Ckm stands for Circuit Kilometers, equal to 1000 Kms. length of circuit, a circuit is the complete path of wires and equipment along with an electric current flows.

11 54 Diagram 3.3: A typical substation at a power plant The step-down substations receive the transmitted electricity from transmission grid for distribution purposes. A distribution substation performs various functions: It transforms the transmission voltages (in the tens or hundreds of thousands of volts range) down to distribution voltages (typically less than 10,000 volts). Distribution buses split the power in multiple directions. Its circuit breakers and switches are used either to disconnect the substation from the transmission grid or separate the distribution lines from the substation. In diagram 3.3, the box in foreground is a large transformer which is getting power from the left sided transmission grid and passing it to right sided distribution bus and three voltage regulators. In distribution substations, the power goes from the transformer to two separate sets of distribution lines with different voltages via distribution buses. The transformers down the transmitted voltage to standard line voltage (usually 7,200 volts) and the remaining power is transmitted to another substation in two sets of three wires at higher voltage. Regulator banks are used to prevent under and over voltage conditions on transmission lines. DHBVNL and UHBVNL are aimed at setting new benchmarks in various areas: (i) serving consumers and improving customer satisfaction by extending reliable,

12 55 quality, uninterrupted, safe, and clean power at affordable tariffs, (ii) controlling line losses by taking various measures, (iii) Improving collection efficiency, (iv) encouraging electricity saving activities, (v) continuous up-gradation of management system, and (vi) using information technology for improving efficiency in the system. In order to ensure uninterrupted and qualitative electricity supply, the distribution utilities take various measures like segregation and rehabilitation of lengthier and overloaded feeders, setting up additional pole mounted substations, construction of additional 33 KV grid substations, augmentation of capacity of existing substations, providing dedicated/independent transformers to farmers, using High Voltage Distribution System (HVDS) for improving HT/LT ratio, strengthening energy audit system and cent-percent metering, reducing theft/pilferage and misuse of electricity, and taking stringent punitive action against unscrupulous people committing electricity theft practices. The utilities undertake various measures for controlling line losses including strict actions against the bill defaulters, using new billing and collection techniques, using prepaid metering system, and facilitating good payer consumers with better services. Optimum use of electricity is ensured with (i) separation and segregation of agriculture and rural domestic loads, (ii) providing independent feeders to industries and reactivation of power management through capacitor installation, (iii) encouraging diversification from water guzzling crops to lesser water consuming crops, (iv) promoting use of standard quality electricity gadgets and machines for conservation of electricity, and (v) promoting remodeling and modernization of pump-sets. The utilities also try to bring cost effectiveness in their operations by (i) encouraging ideas, talent and value system to increase revenues and reduce operational expenses, (ii) promoting a work culture that

13 56 fosters individual growth, team spirit and creativity, (iii) making profit centers which buy the required power, pay for it, and meet their expenses through their own income, (iv) using information technology to improve transparency in the system with web based database publishing, paperless offices, E-billing, on line payment, ATM type cash collection centers, and (v) enabling use of communication means to maximum number of employees like E tendering, Network mapping, Data logging, Remote Meter Reading, and Electricity Distribution Automation. d. Haryana Electricity Regulatory Commission (HERC) The HERC is the regulatory body which advises the State government to take appropriate steps for balancing the interests of consumers, power entities, and generation companies. It also supports government to regulate and promote the workings of in an efficient, economical and equitable manner. The HERC handles consumers problems by following two official procedures: (i) Licensee's Complaint Handling Procedure and (ii) The Commission's Complaint Handling Procedures. Various activities of Haryana Power Utilities are regulated by HERC like (i) purchase, distribution, supply, and utilization of electricity, (ii) the quality of delivered services, and (iii) fixation of tariff rates and other charges levied for supplied electricity. The commission promotes competitiveness by ensuring participation of private sector in different functional stages of the system. It sets an appropriate code of conduct for electricity industry and undertakes measures to balance the interest of various stake-holders in the power sector, namely electricity consumers, power entities, and generation companies.