Matrix of importers and exporters of electricity, emission inventory and site selection

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1 3 Matrix of importers and exporters of electricity, emission inventory and site selection The main objectives of this chapter are to analyse the impact of electricity transfer on the spatial distribution of pollution loads in India and to identify the site for further work. In order to achieve these objectives, following steps have been followed: a) Preparation of a matrix of importers and exporters of electricity to identify the major exporting regions; b) Estimation of emissions of air pollutants i.e. Suspended Particulate Matter (SPM) 1, Nitrogen oxides (NO x) and Sulphur dioxide (SO 2) from power plants; and, c) Quantification of the pollution loads due to power generated for the purpose of export only and site selection for further work. Following a brief account of Indian power sector, states have been categorised as electricity exporting or importing states and the amount of electricity export and import has been estimated. An emission inventory of coal-based power plants in India has also been developed in order to assess the additional pollution load as a result of electricity generation for transfer. Based on this analysis, a major electricity-exporting region is selected for further detailed work in terms of health damage assessment. 3.1 Matrix of importers and exporters of electricity Background Intra-Region Power Transfer After independence, The Electricity Supply Act, 1948 was enacted to establish the State Electricity Boards. It assigned the responsibility of energy utility 1 SPM refers to particles up to 100 micro metres diameter (more usually referred to as total suspended particles or TSP)

2 development to the states. Thus, electricity was generated as well as distributed within the state administrative boundary. Subsequently, in mid seventies the transfer of power from one state to another commenced with the Government of India s intervention to establish the central sector agencies for power development. It was aimed to overcome the disparity in power sector development among the states due to non uniform distribution of power generation resources, economic conditions and constraints of infrastructure services. In 1964, Regional Electricity Boards (REBs) were formed to help interstate power transfer and regional planning was adopted for the development of the power sector. India was divided into five regions for power development, viz., Eastern region (E), Western region (W), Southern region (S), Northern region (N) and North-Eastern (NE) region. The central sector plants were established in the mid-seventies in each region to supply electricity to states of that particular region. Thus, the aim was to make each region self-sufficient in terms of power generation (CPU 1993, Varma 1997, Rao 2004 and CEA 2004a). Under this scheme large pithead coal-based power plants and large hydro power plants were commissioned. These stations supplied electricity to the adjacent states in the respective regions according to their assigned allocations. The principle of global accounting 2 for energy transactions was adopted. According to this, 85% of the available capacity was allocated to different states/constituents of the region. The remaining 15% was kept under the control of the Central Government. This 15% was allocated by the Ministry of Power (MoP)/ Central Electricity Authority (CEA) to states within or outside the region. Of the other 85%, a 10% share was allocated to the home state where the central sector thermal station was situated. The rest of the power was allocated to different states in the region based on their energy consumption 5 years prior to the period when allocation was made (Mitra 1997) Inter-Region Power transfer The adoption of regional planning did not completely serve the purpose of making each region self-sufficient. It was observed that the Eastern region had 2 Global accounting is a commercial accounting procedure agreed by organisation/constituents, participating in the integrated grid operation, where the booking of net energy exchanges is done globally without identification of source of energy. TERI University-Ph.D. Thesis,

3 substantial surplus power throughout the year while the other regions were unable to meet the demand due to regional non-uniform distribution of power generation resources. However, there existed seasonal and off-peak surpluses in these regions as well (CEA 2004a and Mitra 1997). The North East (Meghalya, Manipur, Assam, Arunachal Pradesh, Nagaland, Mizoram and Tripura) is endowed with hydro resources whereas the Eastern states (Bihar, West Bengal, Orissa and Jharkhand) of the country are endowed with coal resources. Thus, the focus shifted to inter-region transfer of power via formation of a national grid. To facilitate the transfer of power from one state to another, agencies like the Power Grid and Power Trading Corporation have been established. The transfer of power has started through inter-regional link. The inter-regional exchanges increased from Gigawatt Hour (GWh) in to GWh in (CEA 2004a). Inter-regional exchanges of energy for the year have been shown in Figure Northern Region (N) Western Region (W) Eastern Region (E) North Eastern Region (NE) Southern Region (S) Source: CEA Annual Report ( ) Figure 3.1 Inter-regional energy exchanges (GWh) in Note: N includes Uttranchal, Uttar Pradesh, Punjab, Haryana, Delhi, Chandigarh, and Himachal Pradesh, Jammu and Kashmir E includes Bihar, Orissa, West Bengal, Jharkhand and Sikkim W includes Maharashtra, Madhya Pradesh, Rajasthan, Gujarat, Daman & Diu, Dadar and Nagar Haveli, Goa TERI University-Ph.D. Thesis,

4 S includes Karnataka, Andhra Pradesh, Tamil Nadu, Kerala, and Pondicherry NE includes Assam, Arunachal Pradesh, Nagaland, Tripura, Manipur, Mizoram, Meghalaya. While the interconnection of grid is necessary to optimise the utilization of energy for the country s overall development; the associated problem could be in terms of a regional imbalance of the pollution load due to concentrated pattern of power generation especially in regions where the power generation is through coal. The Central Pollution Control Board (CPCB 2003) reported that thermal power plants contribute 89% of SO2 and 82% of PM10 (Particulate Matter less than 10 microns in diameter) of the total emission load generated from different categories of industries Methodology A matrix of importers and exporters of electricity can be prepared at different scales; for instance, matrix showing electricity transactions at regional level, state level or even at the unit level. This work presents a matrix showing power transaction at the state level, because: a. in region-based planning, electricity from the central sector power plants is allocated to states within the region. b. according to Clause 6 of the Electricity Act 2003, the State Government has the responsibility to supply electricity to all areas including villages and hamlets (CEA 2005b). c. According to Article 48 A of the Indian constitution the state should endeavour to protect and improve the environment and to safeguard the forest and wildlife of the country. The matrix of importers and exporters of energy generation will comprise of an array of elements that demonstrate the power transfer from one state to the other. It has been possible to come up with a matrix that identifies the net electricity import/ export from a state. The matrix has been prepared by calculating the amount of surplus/deficit in states with respect to the state s own generation along with the generation from central sector plants in that state. The surplus or deficit for each state has been calculated using the formula: Surplus or Deficit = Net generation (Consumption + Losses) TERI University-Ph.D. Thesis,

5 If net generation were more than the consumption and losses in the state, then it would imply that surplus energy is transferred to other states. Accordingly, states generating electricity more than their consumption are exporters of electricity while the states having generation less than their consumption are the importers of electricity. This gives the amount of net electricity exported or imported from each state. The matrix has been compiled for the year The data of consumption and losses and the data for calculation of net generation (i.e. gross generation and auxiliary consumption) for the year are taken from CEA (2004b) and CEA (2004c) respectively. 3.2 Emission Inventory Emission inventory is the listing and description of air pollutant emitting sources, including estimated pollutant emission quantification (Hammerle 1976). Direct monitoring from the source, computer simulations and rapid assessment are the established methodologies to estimate emissions. India is the third largest producer of the coal, but Indian coal is of poor quality with high ash content (35-40%) and low calorific value (gross heat of combustion). The main emissions from thermal power plants are Carbon dioxide (CO 2), Nitrogen oxides (NO x), Sulphur Oxides (SO X), and air borne inorganic particles such as suspended particulate matter (SPM) and other trace gas species. CPCB (2003) reported that thermal power plants contribute 89% of sulphur dioxide (SO 2) and 82% of particulate matter (PM 10) of total emission load generated from different categories of industries. Several authors have prepared an emission inventory of power plants in India using the emission factors, which is actually rapid assessment methodology (TERI 1998, Papney 2001, Garg et al. 2001a,b & 2002a,b, Reddy and Venkataraman 2002). Mittal and Sharma (2004) used stoichiometric analysis for developing the emission inventories of gaseous pollutants. However, the estimation of SPM, They have taken into consideration the ash content in coal and the efficiency of electrostatic precipitator. TERI University-Ph.D. Thesis,

6 Since the temporal domain of the matrix of importers and exporters of energy generation for this study is , it is imperative to prepare an updated emission inventory for the same time period. Although, direct monitoring provides more accurate inventory, this method is extremely time consuming and resource intensive and even impractical for a large and complex study. In terms of the objectives of this study, we need to estimate emissions from 78 coal based power plants. It is unfeasible either to monitor all these power plants or to collect the information on emissions and process parameters. Therefore, the emission inventory is prepared in this study through a rapid source inventory technique, which requires fuel consumption data and emission factors 3. It is convenient to use this method because of its simplicity and modest data requirement especially when it is required to cover large number of sources. The disadvantage however, is in terms of variability in emissions from the normalized emission due to variation in fuel quality, technology, end of pipe controls and their efficiency (Economopolous 1993). A plant-wise emission inventory of coal-based power plants has been developed for the year The pollutants considered for emission inventory are SO 2, NO x and SPM. Emission inventory has been developed using the formula: E E f Q f E is emissions in kilograms per year (kg yr -1 ) E f is emission factor for pollutant in kilograms per tonne (kg t -1 ) Q f is the quantity of coal used for each power plant (t yr -1 ) In this work, annual plant-wise coal consumption data for the year has been collected from CEA (2005a). Different agencies have developed emission factors, such as USEPA (1995), EEA (2001), Economopolous (1993) and IPCC (1997). However, in this study, emission factors developed for Indian power plants by Central Pollution Control Board (CPCB) have been used to estimate the plant-wise emissions of SPM and SO 2 (CPCB 1994). 3 The emission factor is defined as statistical average of the rate at which pollutant is released to the atmosphere, as a result of certain activity such as fuel combustion to generate power. TERI University-Ph.D. Thesis,

7 For coal based power plants these emissions are controlled (as power plants are equipped with Electrostatic Precipitators). In case of NO x, the emission factor has been taken from Economopolous (1993). The emission factors used have been presented in Table 3.1. The sulphur content of Indian coal varies from 0.4% to 0.8% (CCO 1998). For this study, the sulphur content is assumed to be 0.5% in case of coal and 1% in case of lignite. Table 3.1 Emission factors used for inventory preparation Fuel Pollutant Emission factor ( Kilogram per tonne of coal ) Coal Lignite SPM 1.20 SO S a NOx b 7.5 SPM 0.64 SO S NOx b 6.0 a S is weight % sulphur in coal b Tangentially fired boilers for coal-based generation. Source: CPCB (1994), Economopolous (1993) 3.3 Estimation of additional pollution loads from power transfer The additional pollution loads due to power export at the state level have been estimated by multiplying the emissions per unit generation with the amount of power export in the individual states. The emissions per unit generation were calculated by dividing the total emissions from the power plants in the state with the gross generation from coal- based power plants in the respective state. 3.4 Results Exporting and importing regions The electricity exporting and importing regions, identified as per the methodology explained in section 3.1.2, showed that there are a few states where power generation is more than consumption 4 (Table 3.2) and these states are exporting electricity to other states. Amongst these, Himachal Pradesh, Uttranchal, Sikkim, Manipur, Tripura, and Arunachal Pradesh have mainly 4 There is a small difference between all India total net import and net export, which is merely 0.23% of the all India total energy generation by utilities for the year This difference is attributed to the ambiguity in the data prevailing due to use of two different data sources. TERI University-Ph.D. Thesis,

8 hydro-based electricity generation. However, except for Himachal Pradesh, the export of electricity is significantly less amongst the predominantly hydro-based electricity generating states. On the other hand, majority of the export is from the states where generation is mainly coal based. Amongst the major power exporting states, West Bengal and Chattisgarh have predominantly coal-based generation i.e % of the state s total generation. Madhya Pradesh also has significant generation from coal (94%). In Uttar Pradesh and Andhra Pradesh, 79-80% of the state s total generation is coal based and the rest is predominantly gas based. Similarly, Orissa too has 78% of power generation from coal and the remaining power generation is from hydro-based plants. Table 3.2 Electricity exporting states, net export and percentage share of generation based on different fuels in Export (GWh) % diesel % steam % hydro % gas % nuclear % wind Uttar Pradesh(N) Chhatisgarh(W) West Bengal(E) Andhra Pradesh(S) Himachal Pradesh(N) Madhya Pradesh(W) Orissa(E) Tripura(NE) Sikkim(E) Arunachal Pradesh(NE) Manipur(NE) Uttranchal(N) A&N island(e) There are 18 states and 4 union territories that are net importers of electricity (Table 3.3). The major importing states are Maharashtra, Delhi, Haryana, Gujarat, Punjab, Rajasthan, Karnataka and Kerala. States like Maharashtra, Delhi and Haryana are importing huge amount of electricity despite significant generation within their own territory. The estimated export and import of power calculated is the net export and net import, respectively. Under surplus conditions, an importing state can also export power but in totality, it imports more electricity than it exports. The net TERI University-Ph.D. Thesis,

9 total export and import of power includes export from the central sector power plants as well as bilateral trading among the states. Table 3.3 Electricity importing states and net import in States Net Import (GWh) Maharashtra(W) Delhi (N) Haryana(N) Gujarat(W) 6916 Punjab(N) 5909 Rajasthan(N) 5208 Karnataka(S) 4607 Kerala(S) 4346 Goa (W) 2663 Tamil Nadu(S) 2490 Pondichery(S) 1700 Jharkhand(E) 1686 D&N Haveli(W) 1504 Chandigarh(N) 1059 Daman &Diu(W) 966 Bihar(E) 742 Assam(NE) 477 J&K (N) 314 Mizoram(NE) 268 Nagaland(NE) 133 Meghalya(NE) 103 Lakshadweep(S) Pollution due to thermal power generation The emissions for the year have been estimated using the methodology explained in section 3.2. It has been observed that the Indian power sector contributed 2.39 Mt (million tonnes) of SO2, 0.31 Mt of SPM and 2.0 Mt of NOx in The complete estimated emission inventory of all power plants has been provided in Annexure I. The 10 highest pollutant-emitting power plants are represented in Figure 3.2. These power plants come under the central sector, except Chandrapur (Maharashtra), Vijaywada (Andhra Pradesh) and Wanakbori (Gujarat). TERI University-Ph.D. Thesis,

10 SPM SO2 NOx Emission (Tonnes per year) Vijaywada Wanakbori Farraka,NTPC Anpara Singrauli,NTPC Ramagundam, NTPC Vindyachal,NTPC Chandrapur Korba,NTPC Neyveli States Figure 3.2 Top ten pollutant emitting power plants in In the case of central sector power plants, high emissions can be attributed to high installed capacity. The five hotspots in terms of emissions of SPM are Korba (Chattisgarh), Chandrapur, Vindhyachal (Madhya Pradesh), Ramagundam (Andhra Pradesh), and Singrauli (Uttar Pradesh). Likewise, in the case of SO 2 and NOx, Neyveli, Korba, Chandrapur, Vindhyachal and Ramagundam are the top five ranked power plants in terms of emissions. Neyveli power plant has highest SO 2 emissions since the sulphur content in lignite is much higher than coal. However, we observed that the hotspots are different with respect to specific emission rates i.e. in terms of emission per unit of generation. These plants are Vijaywada, Khalgaon (Bihar), Rayalseema (Andhra Pradesh), Patratu TERI University-Ph.D. Thesis,

11 (Jharkhand), and Farraka (West Bengal). These plants are consuming more coal per unit of power generation, and therefore, measures should be taken to improve their efficiency and reduce emissions Pollution loads corresponding to power export From the results of matrix of the importers and exporters of electricity generation, it can be observed that except for Himachal Pradesh, the export takes place mainly from coal-based power generating states. Moreover, hydropower generation does not have the same environmental concerns as that of coal based generation. There will undoubtedly be other externalities associated with the hydropower generation but these externalities are being taken care of by the government. The states that have export-oriented hydrobased power plants, are receiving 12% of the electricity generated by these plants free of cost as a compensation for using the water resources available in the state. On the other hand, power-exporting states where generation is predominantly coal-based, are not receiving any compensation. Therefore, in this study, electricity exporting states having predominantly hydro-based generation will not be considered for further analysis. It was observed that the hydro/nuclear/gas based power stations in major exporting states are under the state sectors, which are dedicated to supply electricity within the state (explained in section 2). Therefore, it is assumed that all the export of electricity is from coal-based generation. However, Uttar Pradesh is an exception where approximately 19% and 7% of the generation in was from central sector export-oriented gas and nuclear-based plants, respectively and export from these plants accounted for 28% of the total export from Uttar Pradesh. Hence, to calculate additional pollution loads in case of Uttar Pradesh, the power exported from gas and nuclear-based power plants from the total export of Uttar Pradesh. In case of gas-based power plants, there are some emissions of SO 2 and NO x but these are negligible as compared to emissions released from coal-based power plants. The additional pollutant load due to power export during the in major power exporting states is illustrated in Figure 3.3. The lower portion of each bar TERI University-Ph.D. Thesis,

12 is the pollution load due to power consumption within the state while the upper portion depicts the pollutant load due to power export. The methodology used for the estimation is presented in section 3.3. The results showed that in , the total additional pollution load of SPM, SO 2 and NO X were , and tonnes respectively, due to export from all the power exporting states where generation is primarily coal-based. It can be seen that Uttar Pradesh is at the top amongst the power exporting states. It exported GWh electricity in a year to other states, which was 45% of its total generation. It is estimated that this additional power generation for other states resulted in tonnes of SPM, tonnes NO x and tonnes of SO 2 release in This pollution load is distributed in the area around the power generation centres. Chattisgarh is ranked at the second rank with GWh power export. It is noteworthy that this exported power is 50% of the state s total generation i.e. Chattisgarh is exporting half of its power to the other states and as a consequence , and tonnes of SPM, SO 2, and NO x, respectively were released in Chattisgarh in a year. The other major exporting states are West Bengal, Madhya Pradesh, Andhra Pradesh and Orissa. West Bengal exported approximately a quarter (i.e. 26%) of its total electricity generation and the remaining major power exporting states i.e. Madhya Pradesh, Andhra Pradesh and Orissa also had 13%, 15% and 9% of the pollution loads from electricity generation attributable to generation for export. Figure 3.4 represents the map of India with state administrative boundaries, export and import status of electricity generated and major power plants located in the exporting states. The major generation pockets/centres are Singrauli 5, Korba (Chattisgarh), Talcher (Orissa), Ramagundam and Simhadri (Andhra Pradesh) and Farraka (West Bengal) with installed capacities of 6180 Megawatt (MW), 3390 MW, 1173 MW, 2100MW, 1000 MW and 700 MW respectively 6 (as on March 2003). The Singrauli region will have approximately 9000 MW capacity in the near future including generation plants under the state sector. 5 Singrauli area extends in the two states i.e. in eastern part of Sidhi district in the state of Madhya Pradesh and the adjoining southern part of Sonebhadra district in the state of Uttar Pradesh. 6 Total installed capacity has been calculated from the plant wise information available from Central Electricity Authority, New Delhi. TERI University-Ph.D. Thesis,

13 Similarly in Korba, coal based power plants having total generation capacity of 2875MW got environmental clearance in this area (MoP 2005a & 2006a). Besides, under the central sector, 2640 MW of capacity addition has been planned for the Bilaspur district of Chattisgarh and 2000 MW has been commissioned at Talcher in Orissa. The Central Pollution Control Board has identified 24 critically polluted areas all over the country, which includes Singrauli, Korba, Talcher and Vishakhapatnam (CPCB 2000). These areas are also included in the recent listing of very critically /critically polluted industrial clusters by CPCB (CPCB 2009). For the year 2002, annual SPM levels were high 7 in Korba and Vishakhapatnam and medium in Talcher and Anpara. Also, critical levels of PM 10 were observed in residential areas of Vishakhapatnam and Korba and high levels of PM 10 were observed at Angul and Anpara. Thus, these locations need immediate attention from policy makers to prevent further degradation of these areas. 3.5 Site selection From the above discussion, it can be concluded that there exists an imbalance of pollution loads amongst different states in India. Appropriate interventions are required to address the disparity of pollution loads in different locations. Also, quantification of damage at these locations is necessary for relevant policy interventions. Since, one of the objectives of the present study is to assess the damage at one of the major electricity-exporting location; this section identifies the region for further study. Following criteria has been defined in order to select the site for further work: 1) It should be in a major electricity exporting state. 2) It should have high pollution loads. 3) Future capacity additions are planned. Table 3.4 presents the comparative analysis of major exporting states and locations. Uttar Pradesh is the top most electricity exporting state having high 7 Based on Annual Mean Concentration (microgram per cubic meter of ambient air) of SO2, NOx and SPM and the Notified Ambient Air Quality Standards, the Ambient Air Quality Status is described in terms of Low (Exceedence factor < 0.5), Moderate (Exceedence factor = ), High (Exceedence factor = ) and Critical (Exceedence factor > 1.5) for Industrial (I), Residential and mixed use (R) areas of Cities/Towns in different States/Union Territories (CPCB, 2004). Exceedence Factor is observed annual mean concentration of criteria pollutant divided by its annual standard for the respective class and criteria pollutant TERI University-Ph.D. Thesis,

14 pollution load. In Uttar Pradesh, Singrauli generation location has maximum installed capacity. It has four main power plants Singrauli, Rihand, Obra and Anpara. However, for the present study, we have selected Korba that is ranked second in terms of export because of following reasons: 1) Though Korba is second highest in terms of total electricity export but in terms of percentage of electricity exported compared to generation, it ranks first i.e. it exports approximately 50 % of the electricity generated. 2) Korba East power plant is not complying with emission standards (CPCB, 2003). The power plants not complying in each state are mentioned in Table ) Further capacity addition is planned in this site. Details of capacity additions have been provided in Table ) In comparison to Madhya Pradesh, Andhra Pradesh and West Bengal, the plants are located at one location. Therefore, pollution load are concentrated at one point. 5) Practical feasibility in terms of data collection is better at Korba. In the case of Singrauli, this pocket extends in two states i.e. Madhya Pradesh and Uttar Pradesh, and thus requires data collection from two states, which is difficult due to resource constraints. TERI University-Ph.D. Thesis,

15 SPM : state consumption SPM : power export SO2 : state consumption SO : power export NOx : state consumption NOX : power export Emission (Tonnes per year) UP Chattisgarh WB AP MP Orissa States Figure 3.3: Comparison of pollution loads due to power consumption within the state and power export for the year TERI University-Ph.D. Thesis,

16 Figure 3.4 Map of India showing regional boundaries for power sector development, state administrative boundaries, state-wise export and import status of electricity, major power generation plants and their SO 2 emissions.

17 Major electricity exporting state Uttar Pradesh Table 3.4 Details of major electricity exporting states and generation pockets within these states Installed Ranking Planned Ranking of states Major generation plants in states Thermal according projects in terms of power to (MW) pollution loads Installed Ranking capacity Export 8, 9 (Accordin capacity according As on 1-3- g to X (MW) to pollution 2002 Plan) load (MW) Rihand 1000 MW Unchahar SPM SO2 NOX Orissa SPM Chattisgarh Sipat Korba 500 (state sector) Andhra Pradesh Simhadri- 500 Ramagun dam-500 SO2 NOX SPM SO2 NOX SPM SO2 NOX Singrauli Rihand Obra Anpara Unchahar Dadri Talcher Talcher STPS IB valley Korba East Korba west Korba STPS Simhadri Kothagundam R-gundam STPS Non complying power plants Paricha, Obra, Hardua ganj and Tanda Talcher old Korba East Kothagund am Madhya pradesh West Bengal Vindyacha l-1000 SPM SO2 NOX Vindyachal Satpura Amaraknath 3 Kolaghat Barkeshwar Farraka Mejia Source: Central Electricity Authority (2004d) for installed capacity and planned projects New Cossipore, Durgapur, Santaldih, Kolaghat, Bandel, gauripur not complying 8 Taken according to net generation analysis 9 6 th rank is occupied by Himachal Pradesh where major generation is through hydro 10 In West Bengal and Jharkhand tentative target of capacity addition is 13000MW during XI Plan. TERI University-Ph.D. Thesis,