Prospects of wind energy in India

258 Int. J. Global Energy Issues, Vol. 26, Nos. 3/4, 2006 Prospects of wind energy in India G.M. Joselin Herbert Department of Mechanical Engineering St. Joseph’s College of Engineering Jeppiaar Nagar, Old Mamallapuram Road Chennai–119, India E-mail: joselindev@yahoo.co.in S. Iniyan* Department of Mechanical Engineering Anna University Chennai–25, India E-mail: iniyan777@hotmail.com *Corresponding author E. Sreevalsan Wind Resource Assessment Centre for Wind Energy Technology (C-WET) Government of India Velacherry–Tambaram High Road Chennai 601 302, India E-mail: esree@cwet.res.in S. Rajapandian Department of Electrical and Electronic Engineering Sathyabama Institute of Science and Technology Deemed University Jeppiaar Nagar, Old Mamallapuram Road Chennai–119, India E-mail: sraja_pandian@yahoo.co.in Abstract: This paper is a modest attempt to study the growth and performance of wind farms in India. India occupies the 5th place in the world in wind energy generation after Germany, the USA, Denmark and Spain, and has an installed capacity of more than 2485 MW of wind energy, comprising both commercial projects (2418 MW) and demonstration projects (65.415 MW) as of 31 March 2004. This paper discusses the progress mode, wind resource assessment, technological development, environmental benefits and economics in the area of wind energy and also the policies of wind power development in India. It also deals with the performance and Pareto analysis of the wind farm located at Muppandal (in the southern part of India), with an installed capacity of 16.525 MW. It consists of 53 Wind Electric Generators (WEGs). Copyright © 2006 Inderscience Enterprises Ltd. Prospects of wind energy in India 259 Keywords: wind resource assessment; wind power development; wind electric generator. Reference to this paper should be made as follows: Herbert, G.M.J., Iniyan, S., Sreevalsan, E. and Rajapandian, S. (2006) ‘Prospects of wind energy in India’, Int. J. Global Energy Issues, Vol. 26, Nos. 3/4, pp.258–287. Biographical notes: G.M. Joselin Herbert holds a Master’s degree in Thermal Engineering. Currently, he is Assistant Professor in the Department of Mechanical Engineering, St. Joseph’s College of Engineering, Chennai, India. He is doing research on the Reliability and Failure Analysis of Wind Turbine Components at Sathyabama Institute of Science and Technology, Deemed University, Chennai. His area of interest is wind energy conversion systems. Dr. S. Iniyan is Assistant Professor in the Department of Mechanical Engineering, College of Engineering, Anna University, Chennai, India. He has published over 80 research papers in international journals and conference proceedings. He had done his postdoctoral research at the University of Hong Kong, Hong Kong. His field of interest includes renewable energy sources, energy planning and alternative energy sources. He is one of the reviewers for Energy, an international journal. He has 17 years of experience in teaching and research. He is also a member of several technical organisations and committees. Dr. E. Sreevalsan, MSc, MTech, PhD, is Scientist and Unit Chief, Wind Resource Assessment, Centre for Wind Energy Technology (C-WET), of the Government of India, Chennai, India. His area of interest is wind resource assessment. Dr. S. Rajapandian obtained his ME and PhD from the Indian Institute of Science, Bangalore, in 1974. He is a pioneer in capacitor development in India. He was Visiting Professor at Anna University during 1974–1998. He is presently Visiting Professor at Sathyabama Institute of Science and Technology, Deemed University and also Principal of Panimalar Engineering College, Chennai. He has published many papers in national and international journals. His areas of interest are windmill power generation and fuel cells. 1 Introduction Energy is an essential ingredient of socioeconomic development and economic growth. Renewable energy sources like wind energy are indigenous and can help in reducing dependency on fossil fuels. Wind energy also provides national energy security at a time when decreasing global reserves of fossil fuels threaten the long-term sustainability of the Indian economy. With the abundance of wind energy resources in many parts of the country, especially along the coastline, electricity generation through wind energy provides a viable and environment-friendly option. Even among other applications of renewable energy technologies, power generation through wind has an edge because of its technological maturity, lower demand on infrastructure and relative cost competitiveness. 260 G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian A Centre for Wind Energy Technology (C-WET) and 11 other consultancies are providing private technical support to the sector. The Ministry of Non-conventional Energy Sources (MNES), Government of India, has issued guidelines to all the states on the general policies and the facilities to be offered for wheeling, banking and purchase of power from such projects. For thousands of years wind energy has been exploited, but its re-emergence as one of the most effective renewable sources of generation of grid-quality electricity is of relatively recent origin. India’s gross estimated potential stands at 45 195 MW and its technical potential at 12 875 MW (Kalaidasan, 2004). The total generation from wind power projects established in various states in India is 14.17 × 109 kWh. About 16% of the country’s technical potential has so far been developed and 11.9 million kWh fed through various state grids. The per capita electricity consumption in India has risen from 15 to 400 kWh in the past five decades. India has earned recognition as a new ‘Wind Super Power’ according to the 1998 World Watch Institute’s Report (Garg, 2003). The MNES has a grand vision viz ‘Vision 2012’, which aims at the electrification of 18 000 remote villages through renewables, 10% (10 000 MW) of additional new power capacity to come through renewables (wind – 5000 MW; small hydro power – 3000 MW; biomass – 1500 MW; and solar photovoltaic – 500 MW). The estimated potential of various types of new and renewable sources of energy is given in Table 1. Out of this total energy, 45 000 MW is estimated to come from wind energy. The power generation from renewable sources witnessed a remarkable growth during the 8th Five-Year plan period (1992–1997). The 9th Five-Year Plan, i.e., from 1997 to 2002, envisaged a grid-capacity addition of around 3000 MW from New and Renewable Sources of Energy (NRSE) (Reliance Industries Ltd., 2002). The government estimates that a potential of 50 000 MW of power capacity can be harnessed from new and renewable energy sources (TIDEE, 2002). Figure 1 shows the percentage distribution of new and renewable sources of energy sector achievement in India as of 31 March 2004. The total installed capacity was approximately 9273.35 MW, of which 24% was wind based. Table 1 Sl. number Estimated potential of renewable sources of energy Source/technology Potential 1 Biomass energy 195 000 MW 2 Wind energy 45 000 MW 3 Solar energy 20 MW/sq km 4 Small hydro 15 000 MW 5 Energy from waste 6 Ocean thermal power 50 000 MW 7 Sea water power 20 000 MW 8 Tidal power 10 000 MW 1700 MW Prospects of wind energy in India Figure 1 261 New and renewable source of energy (MW) achievement in India as of 31 March 2004 W ind pow er Wind power Hybrid system Hy br idMsy 193.35 W st em 2% 193.35 MW 2485 M W 2485 M W 24% 24% 2% S m al l Hy dr o upt o Sm all hydro upto 25M W 25 M W 1509 M MW W 1509 15% Ener gy r ec ov er y Energy recovery 15% fromururban and f r om ben and 5527 M W 52% ass based B io-Bio-m m ass based 5527 M W pow er 52% p ower 484 M W 484 M5% W 5% S olar P hot o v ol t aic Solar 121 photo voltaic MW 121 M W 1% 1% 2 Bio-m assgasi gasifiers B iom ass f i er s 53 M W 53 1% MW 1% Development of wind energy The wind power programme in India was initiated towards the end of the 6th plan in 1983–1984 (Garg, 2003). A detailed study on wind energy resource in India, in the establishment of wind farms on a scientific basis, was started in the year 1986 in Gujarat and Tamilnadu, where wind conditions appeared most favourable. The wind power programme in India is promoted and coordinated by MNES, Government of India. The ministry has adopted a market-oriented strategy since its inception and the considerable groundwork done during the 7th plan (1985–1990) and up to 1992 resulted in rapid commercial development during the 8th plan (1992–1997). Government incentives – in the form of tax holidays and accelerated depreciation – acted as the motivation for private wind farm developers in all countries. The wind power capacity in Europe increased fivefold from 1990 to 1995 to become 2500 MW. The wind power capacity at the end of 1995 in various countries was: USA – 1650 MW; Germany – 1130 MW; Denmark – 610 MW; and India – 580 MW. With additional capacity in the year 1996, India has reached a proud 3rd place in wind power installation. Thereafter, it became the 4th up to December 1998, and now it is in 5th place. The additional capacity in wind-generated energy in India over the last 13 years has been 42.4, 12.7, 61.1, 235.5, 382.1, 169.1, 66.8, 55.9, 142.9, 172.5, 287.4, 241.3 and 613.7 MW. It can be seen from Table 2 that the major part of the installed capacity came from Tamilnadu during the past decade. As for wind power capacity state-wise, 54.8% has been installed in Tamilnadu, 16.3% in Maharashtra, 8.12% in Gujarat, 8.41% in Karnataka, 3.97% in Andhra Pradesh and 7.18% in Rajastan. The least is in Orissa and West Bengal (0.09%). The states with installed capacity can be identified from the given map of India. 262 G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian Figure 1.1 State-wise installed capacity of wind power in India (as on 31 March 2004) 178.5 MW 22.6 MW 202 MW 1.1 MW 1.1 MW 407.4 MW 98.8 MW 209.2 MW 2 MW 1361.6 MW Map showing state – wise installed capacity of wind power in India (As on 31st March 2004) 2001–2002 2002–2003 2003–2004 Total capacity (MW) 17.8 45.6 41.9 44.9 132.8 371.3 1361.6 Gujarat 0.0 0.0 0.0 0.0 6.2 28.9 202.2 Andhra Pradesh 6.0 26.3 3.8 0.7 0.0 6.2 98.8 23.3 50.3 110.6 209.4 2.0 6.2 407.4 Karnataka 2.6 14.6 10.4 24.0 55.7 84.9 209.2 Kerala 0.0 0.0 0.0 0.0 0.0 0.0 2.0 Rajastan 0.0 2.0 5.3 8.8 44.6 117.8 178.5 Madhya Pradesh 6.2 4.1 0.0 0.0 0.0 0.0 22.6 Orissa 0.0 0.0 0.0 0.0 0.0 0.0 1.1 West Bengal 0.0 0.0 0.5 0.6 0.0 0.0 1.1 Others 0.0 0.0 0.0 0.0 0.0 0.0 1.6 55.9 142.9 172.5 287.4 241.3 613.7 2485.9 Tamilnadu Maharas-Htra Total MW 263 2000–2001 Prospects of wind energy in India 1999–2000 Growth of wind power installed capacity (MW) in India as of 31 March 2004 1998–1999 Table 2 Year States 1994–1995 1995–1996 1996–1997 1997–1998 Tamil Nadu 22.3 11.5 50.5 190.9 281.7 119.8 31.1 Gujarat 14.4 1.6 10.6 37.7 51.2 31.1 20.1 Andhra Pradesh 0.6 0.0 0.0 5.4 38.9 9.4 1.5 Maharas-Htra 1.1 0.0 0.0 1.5 0.0 2.8 0.2 Karnataka 0.6 0.0 0.0 0.0 2.0 3.3 11.2 Kerala 0.0 0.0 0.0 0.0 2.0 0.0 0.0 Rajastan 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Madhya Pradesh 0.6 0.0 0.0 0.0 6.3 2.7 2.7 Orissa 1.1 0.0 0.0 0.0 0.0 0.0 0.0 West Bengal 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Others 1.6 0.0 0.0 0.0 0.0 0.0 0.0 42.4 12.7 61.1 235.5 382.1 169.1 66.7 Total MW G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian 1993–1994 264 1992–1993 Growth of wind power installed capacity (MW) in India as of 31 March 2004 (continued) Up-to March 1992 Table 2 Year States Prospects of wind energy in India 265 The cumulative installation of Wind Electric Generators (WEGs) is shown in Figure 2. It is found that the wind power sector has shown a well-registered remarkable growth in the last 18 years. A cumulative number of 7013 WEGs with different capacities were installed as of 31 March 2004. The additional wind power capacity in India as of 31 March 2004 is shown in Figure 3. It is noted that there was an accelerated growth in the wind power sector from 1993 to 1996 because of a booming economy and attractive fiscal incentives. Investment fell sharply from mid-1996 onwards owing to a reduction in corporate income tax and withdrawal of third-party sale. The scenario started looking up from 1999 because of technological maturity and the introduction of machines suitable for Indian conditions. Figure 2 Cumulative number of WEGs in India as of 31 March 2004 Number of WEGs 8000 7000 6000 5000 4000 3000 2000 1000 19 86 19 87 19 88 19 89 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 02 20 03 20 04 0 Year Figure 3 Additional wind power capacity (MW) in India as of 31 March 2004 700 500 400 300 200 100 0 19 86 19 87 19 88 19 89 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 02 20 03 20 04 Additional wind power capacity (MW) 600 Year G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian 266 The cumulative generation of wind energy as of 31 March 2004 was 14.17 × 109 kWh, as found in Figure 4. Wind farming in India boomed in 1994 – one year after the government’s declaration of incentives to private entrepreneurs. Many large and small industries invested in the wind power programme, which brought them tax exemptions. Numerous private wind farms came up at Muppandal, Kayathar and Kethanur in the State of Tamilnadu. Figure 4 Cumulative generation (MWh) from wind power projects in India as of 31 March 2004 16000000 14000000 Cummulative generation (MWh) 12000000 10000000 8000000 6000000 4000000 2000000 0 1986- 1992- 1993- 1994- 1995- 1996- 1997- 1998- 1999- 2000- 2001- 2002- 200392 93 94 95 96 97 98 99 00 01 02 03 04 Year The growth of private sector wind farms was relatively lower in the State of Gujarat. However, eight states of the country have grid-connected wind electricity generation today. As it happens, the growth rate declined when the initial enthusiasm withered away. Reports claim that a mediocre performance of installed machines at many sites, unpredicted technical issues and speculations on the future may prevent further investment at the rate experienced earlier. Installation peaked during 1995–1996 with a total additional capacity of 382 MW during that year. The progress slowed down during the early years of the 9th plan (1997–2002). As a result of concerted efforts and an improved policy regime in a few states, installations started to pick up again towards the end of the 9th plan and a capacity of about 550 MW came up during the first two years of the 10th plan (2002–2007). Significant thrust has been provided to captive generation. Further growth in this field will greatly depend upon the economic operation and the competence of technology. 2.1 Demonstration projects Initially, the Government of India established four demonstration wind farms in the year 1985 at Tuticorin (Tamilnadu), Okha (Gujarat), Puri (Orissa) and Deogarh (Maharashtra). As of 31 March 2004, the demonstration wind – farms, with 385 WEGs, have been established at more than 36 different locations. In Tamilnadu and Gujarat, 29.59% and 32.2% respectively of total demonstration wind farms were established, as shown in Table 3. Lamba, Kayathar and Muppandal are the three major demonstration Prospects of wind energy in India 267 wind farms in the southern part of India, which were established with the assistance of the Danish International Development Agency in the year 1989–1990. The selection of sites for demonstration projects depends on the average wind power density and the annual wind speed. Year-wise establishment of demonstration wind farms in India is shown in Figure 5. It is found that more demonstration wind farms were established in 1990. The cumulative installation up to the year 2004 was 65.415 MW. The installed capacity varied from year to year. Twenty-two wind demonstration projects were established in 1990, because of which the wind power sector started improving. The main contributing factors were a shift from being a depreciation-driven industry to an energy-driven industry, the introduction of large capacity machines and the offer of incentives by some states. Demonstration wind farms in India (state wise) Table 3 States Number of places Number of Wind Electric Generators Capacity MW 2 20 5.300 Andhra Pradesh Goa 2 2 0.110 Gujarat 7 124 17.840 Karnataka 2 14 2.575 Kerala 2 10 2.125 Madhya Pradesh 1 6 0.590 Maharashtra 6 47 8.980 Orissa 2 21 1.190 Rajastan 3 17 6.350 Tamilnadu 8 120 19.355 West Bengal 1 4 1.000 36 385 65.415 Total Year wise establishment of demonstration wind farm in India Figure 5 25 15 10 5 02 01 00 99 98 97 96 03 20 20 20 20 19 19 19 95 Year 19 93 92 91 90 89 88 87 86 94 19 19 19 19 19 19 19 19 19 19 85 0 19 Additional wind power capacity (MW) 20 268 G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian Recently, the Karnataka Renewable Energy Development Ltd. (KREDL) commissioned a 2 MW demonstration project at Maviahunda in Karnataka state. Under the National Wind Resource Assessment Programme, wind monitoring was taken up on a 25-metre mask, and the data collection period exceeded more than one year at heights of 10 and 25 metres. This site has fairly good Wind Power Density (WPD) of 366 watts/m2 and annual mean wind speed of 24.6 km/h at a 50-metre height. This project utilises the MNES financial assistance of $US976,744 for 2 MW. The award for the work was given in March 2003. The construction activity of the project was actually started on 5 May 2003 in 25 acres of land acquired from the government revenue department. The plant was commissioned on 30 August 2003. This demonstration wind farm of KREDL consists of four three-bladed WEGs of 500 kW capacity, each with a 50-metre hub height and pitch regulation for optimal conversion of mechanical power to electrical power. The estimated generation for the four months from September to December 2003 was 1.45 GWh. But the actual energy generated was 1.52 GWh. Thus, an extra generation was achieved for that period. The concept of the wind energy demonstration scheme initiated by MNES will definitely instil confidence in the investors. Thereby, local area improvement and social uplift will take place. Therefore, more and more demonstration wind power plants with new technologies should be encouraged by MNES, which would give momentum to the comprehensive development of the regions of states with wind potential. 2.2 Private wind farms A notable feature of the Indian programme has been the interest evinced by private investors/developers in setting up commercial wind power projects. Many manufacturers in India, with about 27 foreign collaborators, are producing wind electric generators with ratings of 55 kW to 1.5 MW. Seeing the good performance of demonstration wind farms, a number of private entrepreneurs decided to venture into the establishment of private wind farms. These private wind farms are mainly in the States of Tamilnadu, Gujarat, Maharashtra, Andhra Pradesh, Karnataka and Madhya Pradesh. The total installed capacity of private wind farms was 2418 MW as of 31 March 2004, with about 6628 WEGs installed by about 384 wind turbine owners. Private wind farms have been situated in more than 80 locations in India. More than 95% of investments are made by the private sector. The reasons for the State of Tamilnadu achieving high growth are: • Extension of concession by the Central Government for wind power projects including permission for import of machines under open general licence, customs duty concession, 100% depreciation allowance (now fixed at 80%), five-year tax holiday and 75% loan facility from India Renewable Energy Development Agency (IREDA). • During the initial period (1992–1997), the State Government provided capital subsidy to industries at 10% of the project cost, subject to a maximum of $US34,884, in order to encourage them to invest in wind power. Prospects of wind energy in India 269 • The Tamilnadu Electricity Board (TNEB) paid an attractive price for the power purchased from wind mills, i.e., 2.91 cents to 5.23 cents per kWh with 5% escalation as per MNES guidelines effective 1995. It now stands at 6.28 cents per kWh (Kalaidasan, 2004). • Several manufacturers of wind machines set up production facilities which facilitated the wind farms to get the machines and install them in a short time. • It can be seen from Figure 6 that a major part of the installed capacity came from Tamilnadu during the past decade. The state has also made considerable progress with regard to harnessing the available wind potential and tops the list among states. • Private wind farm developers are allowed the facility of wheeling the power generated from their windmills through the grid network of TNEB for use in their own industries or in subsidiary concerns situated in Tamilnadu on a wheeling charge of 5%. • The private developer has the option of either selling the surplus energy after wheeling or banking it for future use, which energy has to be utilised within the financial year, which ends in March. In case of banking, a further charge of 5% is levied. The year-wise growth of private wind farms in India is shown in Figure 7. It shows that the installation of private wind farms was started in 1991 and there was a positive growth of installation because of the announcement of wind power policies. State wise private wind power installed capacity (MW) in India as of 31 March 2004 1342. 2 399 St at es of I ndi a 172. 1 Ra jas th an Ta m il N ad u M ah ar as ht ra 22 M .P . Ka rn at ak a 93. 4 184. 7 204. 6 Gu jar at 1600 1400 1200 1000 800 600 400 200 0 An dr aP ra de sh Installed capacity (MW) Figure 6 G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian 270 Figure 7 Year wise cumulative installed capacity (MW) of private wind farm in India as of 31 March 2004 3000 Installed capacity (MW) 2500 2000 1500 1000 500 0 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Year 2.3 Future developments The projected new addition of wind energy during the 10th plan period (2002–2007) will be 41 110 MW, and during the 11th plan period (2007–2012) will be 58 890 MW. The breakdown of that additional energy for the 10th plan period is 22 830 MW (55%) from the central sector, 11 160 MW (27%) from the state sector and 7120 MW (18%) from the private sector. The technical potential will increase as the grid capacity increases. In the draft renewable energy policy (11th plan), the Government of India proposes to harness 6000 MW installed capacity of wind power by 2012 at the rate of 500 MW per annum. With the action being taken by the ministry on various energy resource assessments, technology development, local production, exports, financing, policy and regulatory reforms and institutional development, the goal for 2012 is achievable and, in fact, could be brought forward. The reduction in capital cost with a larger volume of business and an increase in efficiency through proper planning and design is a distinct possibility. With these considerations it is hoped that wind power potential will become commercially viable in the immediate future. According to the Indian government, the global wind power from wind turbines is expected to rise from 24 927 MW (year 2001) to over 79 000 MW by the year 2006. Likewise, for India it is to rise from 1546 to 40 256 MW by the year 2006 (Dewl, 2002). The advancement of wind turbine technology is leading to next-generation wind turbines, which promise significant improvements in performance, reliability and cost (Shikha et al., 2003). The technology-related priority areas, where further developmental work is required, are MW-sized wind power systems, improved rotor blades and gear boxes, power quality improvement, wind machines for low wind regimes, advanced control systems, development of cheaper materials and integration of wind farms with weak grids. Prospects of wind energy in India 3 271 Wind resource assessment Wind is air in motion and is the result of the conversion of the potential energy of the atmosphere into kinetic energy, through the work of pressure forces. The ultimate energy source for the earth’s atmospheric system is the sun. The mean monthly values of the intensity of direct solar radiation normal to the solar beam that are received at the earth’s surface at noon in India vary from 0.51 to 1.05 kW/m2, depending on the latitude, altitude of the station and the season (Mani and Mooley, 1983). The increase in wind speed with height is the function of terrain roughness. The wind follows a cylindrical pattern with winds reaching peak speeds once in four years. Electrical anemometer and wind vanes with data loggers are capable of measuring and storing continuous data on wind speed and direction (Mani, 1990). Wind monitoring centres have measured wind speed at several places, of which 211 stations have shown annual average wind-power density of more than 200 Watts/m2 at 50 metres above ground level, which is considered to be a benchmark for the establishment of a wind farm. The locations having an annual mean wind-power density greater than 150 Watts/m2 at a height 30 metres will also be considered for suitable wind power projects. Three years of wind data is considered appropriate for assessing the wind potential of a site. Initially, it was thought that the windy sites were always near the seacoast, but scientific study has proven that windy sites could be far from the seacoast as well. It is not enough to obtain general wind data. Site-specific information on wind speed, direction, frequency, shear, gusts and turbulence is necessary. Complex terrains require microlevel wind resource studies. The temperature humidity of wind fields at the surface during winter at Delhi were examined by Padmanabhmurty and Bhal (1981), who observed that the wind was either calm or light in the suburbs but accelerated towards heated island regions to 10 kmph (Mani and Mooley, 1983). Wind maps are useful for the evaluation of the wind potential of a country or region. Wind site maps indicate the most promising area for wind plant installation (Gaudiasi, 1990). During the period April–May to September–October, the wind is uniformly strong over the whole Indian Peninsula, except the eastern coast, whereas wind during the period of November to March is relatively weak (Windpro Monthly Journal, 2003d). The nationwide wind resource assessment is being carried out by C-WET, Chennai. As many as 24 states and union territories are covered under this programme, with about 900 wind-monitoring and wind-mapping locations. So far, 498 wind-monitoring stations have been established in 17 states and three union territories, of which 60 wind-monitoring stations are established in Tamilnadu. The year-wise installation of wind-monitoring stations is shown in Figure 8. In 1998, 11.39% of 483 wind-monitoring stations had been established. The establishment of wind-monitoring stations steadily increased from 1995. The main purpose of wind-monitoring stations is to monitor the average wind power potential and annual mean wind speed. These data are collected at different heights, and based on this information demonstration wind farms are established. Wind-monitoring stations have also been established at high altitudes ranging from 1500 metres to 3300 metres above mean sea level in different states. It is surprising to note that most of these stations have not shown good wind speed. The only wind-monitoring station at high altitude that has shown very strong wind speed is Baba Budhan Giri in Karnataka (altitude 1600 metres, wind speed 27.60 kmph at 30 metres above ground level). The G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian 272 wind power density at this place is 532 watts/m2 at 30 metres above ground level. The wind-monitoring stations are very useful to identify the proper location in order to install the wind farms. Establishment of wind monitoring stations in India from 1986 to 2003 Figure 8 60 Number of stations 50 40 30 20 10 02 03 20 00 01 20 20 98 99 20 19 96 97 19 19 94 95 19 19 92 93 19 19 90 91 19 19 88 89 19 19 87 19 19 19 86 0 Year 4 Technical development Wind turbine technology has a unique technical identity and unique demands in terms of the methods used for design. Remarkable advances in wind power design have been achieved owing to modern technological developments. Since 1980, advances in aerodynamics, structural dynamics, and ‘micrometeorology’ have contributed to a 5% annual increase in the energy yield of the turbines. Current research techniques have led to the production of stronger, lighter and more efficient blades for the turbines. The annual energy output per turbine has increased enormously and the weights of the turbines and the noise they emit have been halved over the last few years. The windmills set up in the late 1980s and early 1990s do not have devices for lightning protection. Action should be taken to install systems for protection against lightning (Windpro Monthly Journal, 2002a). A doubling of the rotor diameter leads to a fourfold increase in power output, and a doubling of wind speed leads to an eightfold increase in power (Tony et al., 2001). The machines available in the market normally have cut-in speed of around 3 m/s, rated speed of about 14 m/s and cut-out speed of 25 m/s, irrespective of the power rating (Sasi and Basu, 1997). WEGs can vary in size from a hundred kilowatts to several megawatts. The size of the WEGs largely determines the choice of the generator and converter system. Asynchronous generators are more common with systems of up to 2 MW, beyond which direct-driven permanent magnet synchronous machines are preferred (Datta and Ranganathan, 2002). A self-excited induction generator is suitable Prospects of wind energy in India 273 for wind-driven applications with wide variations in the driving speed. The annual production capacity of the wind turbine industry is about 500 MW at present. Enercon model E-30, 230 kW, Enercon E-40, 600 kW, Jeumant 750 kW and Lagerway Lw-58, 750 kW machines are operating without gear. Other machines are equipped with gear. Figures 9 and 10 show the power curve for pitch-regulated and stall-regulated WEGs. The rating of the wind turbine increases depending on various technical particulars. Different wind turbines are producing rated power by different rated wind speed. For example, Vestas-RRB, three-blade, a 27-metre rotor diameter, a 50-metre hub height, pitch regulator, asynchronous dual-speed generator coupled with gear produces rated power of 225 kW at a wind speed of 18 m/s. Similarly, NEG-Micon, 750 kW machine, three-blade, stall-regulated, asynchronous, dual-speed generator coupled with gear, rotor diameter 48 metres, hub height 50 metres, produces rated power of 750 kW at a wind speed of 15 m/s. Suzlon 1000 and 1250 kW machines are producing rated power at a wind speed of 13 m/s. Power curve of pitch power regulated, three blade WEGs Figure 9 1600 Rotor power (kW) 1400 1200 1000 Vestas R R B, 225 kW 800 Vestas R R B, 500 kW 600 Lagerway, 750 kW 400 Suzlon, 1 M W 200 G E W ind Energy, 1.5 M W 25 23 21 19 17 15 13 11 9 7 5 3 1 0 W ind speed (m /s) Power curve of stall power regulated, three blades WEGs Ponieer Wincon 250 kW TTG 250 kW 1000 800 600 400 200 0 25 23 21 19 17 15 13 11 9 7 5 3 Suzlon 350 kW 1 Rotor Power (kW) Figure 10 NEG Micon 750 kW NEG Micon 950 kW Wind Speed (m/s) The variation of turbine performance at the same site depends upon the closeness of site cubic mean wind velocity to the turbine rated speed, the relationship between the speed characteristics cut-in speed (VC), rated speed (VR) and cut-out speed (VF) of the wind turbine and variation of Weibull parameters (Jangamshetti and Guruprasada Rau, 2001). 274 G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian The introduction of higher-capacity machines with larger rotor diameters and higher hub heights will enable more cost-effective harnessing of wind energy. Wind turbines and wind turbine components are also being exported to Europe, the USA and Australia. There is also considerable interest from developing countries in Indian wind turbine equipment and technical services (Windpro Monthly Journal, 2002e). The performance of wind turbines also depends upon the number of blades and blade chord/rotor diameter ratio; the aspect ratio has almost no effect on torque coefficient and power coefficient (Ushiyama et al., 1990). The capacitor of sufficient rating should be provided in the wind electric generator itself to compensate for the power factor of the wind electric generator, so that the power factor is always maintained above 0.85 and the voltage regulation is within 12% of the rated voltage at the point of supply. If the power factor continuously goes below 0.85, it would result in a heavy drawl of reactive power from the grid, leading to higher transmission and distribution (T&D) losses and reduced voltage stability margins. If the power factor goes below 0.85, the wind generator should be disconnected from the grid (Windpro Monthly Journal, 2003e). For the power factor below 0.95, a penalty could be levied, which should be based on a variable rate and not a flat rate (Windpro Monthly Journal, 2003c). 5 Environmental benefits In India, coal is the primary fuel source for generating electricity, accounting for 62.3% of total electricity produced (Windpro Monthly Journal, 2003a). Burning fossil fuels such as coal releases carbon dioxide (CO2), a pollutant. Carbon dioxide emission from the energy sector represents nearly 33% of the world CO2 emission and is projected to increase at 2.7% per annum. India emits about 4% of the global warming pollutant and the USA emits 25%. Carbon dioxide build-up in the atmosphere is the single biggest contributor to global warming. The estimate of CO2 emission from the power sector in India for 1990 is 213 million metric tonnes (Windpro Monthly Journal, 2003a). Total CO2 emission from all the coal-fired power plants in India was 1.1 thousand tonnes per day in 1997–1998, with an annual emission computed to be 395 million metric tonnes. Coal-fired plants cause diverse public health and environmental problems. To address the problem of global warming and environmental degradation, steps need to be taken to slash the amount of CO2 that various power plants emit. The replacement of traditional fossil fuel-based energy with wind energy offers great opportunities for the reduction of CO2 emission. There is no doubt of the good prospects for wind energy in India, especially in states like Karnataka, Tamilnadu and Rajastan. From the environmental point of view, wind energy is the cleanest power. Many companies have entered this field as a service to society and the nation to provide pollution-free energy to the public. Apart from direct benefits like augmentation of power generation and contribution to energy security, wind power projects also result in substantial socioeconomic and environmental benefits. Wind farms require 0.08 to 0.13 km2/MW. Ninety-nine percent of the land occupied by a wind farm can be used for agriculture (Andersen and Jenson, 2000). The estimated environmental benefits of installing wind farms could be the reduction of the following emissions annually. Prospects of wind energy in India 275 CO2 2100 metric tons/MW SO2 2.5 metric tons/MW NOX 1.7 metric tons/MW Total suspended particulate 0.5 metric tons/MW Moreover, the introduction of grid-connected wind power projects results in direct and indirect generation of employment. The equivalent saving of coal and reduction of other pollutants by use of wind power generators up to 31 March 2004 is depicted in Figure 11. This figure shows that apart from the saving of coal, the emission of CO2 is reduced to the extent of 14.17 × 106 tonnes. Figure 11 Equivalent saving (in tons) of coal and reduction of other pollutants by use of wind power generators as of 31 March 2004 Particulate 7620 tons Coal 5669760 tons SO 2 92130 tons CO 2 14174400 tons 6 NO 2 63780 tons Economic analysis of wind energy The technical and economic feasibility of wind farms was established by 1987. Setting up wind farms is an ideal tax-planning scheme. While Board tariff will go up year by year, the cost of energy from windmills will come down (Narayanaswamy, 1993). The economics of wind energy depends on: • wind speed at a given project site • improvement in turbine design, bringing down cost • size of wind farm • optimal configuration of the turbine • cost of financing • transmission, tax, environmental and other policies (Windpro Monthly Journal, 2004). 276 G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian The gap between the cost of wind-generated electricity and that of energy from conventional sources of generation is steadily narrowing. One kWh of wind power generated was considered to be equivalent to 2.97 kWh of primary energy (Windpro Monthly Journal, 2003d). A shorter gestation period for wind farm and earlier power generation are the major characteristics of wind energy economic analysis (Windpro Monthly Journal, 2002c). The cost of generation per kWh depends on total fixed cost and net generation. A detailed Statement of Cash Flow for a period of ten years is shown in Table 4. It will be seen from the table that bank loans along with interest have been wiped out by the 7th year and that economics of wind energy is really a boon. A few years after installation, the cost of generation is very attractive. The operation and maintenance costs are uniform over the years. The cost of kWh generation was $US0.33 during the first year and has gradually decreased; it was $US0.06 during the 10th year. The net profit and the total cost of adjustment have increased year by year. The economics of wind energy has changed dramatically over the past 20 years, as the cost of wind power has fallen approximately 90% during that period. The factors affecting the cost of wind energy are still rapidly changing, and wind energy’s cost will continue to decline as the industry grows. The differences in one metre per second of wind speed can mean differences of a cent or more per kWh in the cost of electricity production. The average yearly contribution of the Cost of Capital (CC) to the total cost of electricity is: CC = ( ICC × CRF ) $ ; ( Pr × CF × 8766 × 43) kWh ($1 = 43Rs.) where ICC is the total installed cost in dollars, CRF is the capital recovery factor, Pr is the rated capacity of the wind turbine, CF is the average capacity factor and 8760 is the number of hours in one year: CRF = r /(1 − [1 + r]− n ) where r is the interest rate and n is the assumed life of the installation. For a 25-year life, if r = 6%, CRF = 0.0782 (Cavallo et al., 1993). Turbine cost is the largest portion of the project cost and it comprises more than 70% of the total installation cost of wind plants. The extra cost of the tower is in the order of $US1570 per one metre extra height. A study by the International Energy Agency (IEA) says there will be an 18% reduction in energy prices if wind energy capacity continues to double every three years, and there will be a 30% reduction in price in the year 2006 (Windpro Monthly Journal, 2003b). At present, at a good site the wind energy cost is $0.06 per kWh (Kalaidasan, 2004). Operation and maintenance costs – in the range of 0.6–0.8 cent/kWh – compare remarkably well with the other, often used backup sources (Sangaranarayanan, 1999). Operational costs are falling as turbines increase in size. The manufacturing cost of a wind turbine is primarily proportional to its mass. The absolute mass of the tower head increases with rotor diameter. The rise in the specific cost can be compensated by the rotor’s specific energy yield, which also rises with wind turbine size. Wind turbines with blade pitch control were considerably more expensive than comparable machines with a fixed blade pitch. The introduction of a blade-pitch system increases the cost of a wind turbine by about 4%. The cost of electricity through the wind energy system can be further decreased in the future by improving the technology and increasing the manufacturing potential. Description 1 2 3 4 5 6 7 8 9 10 Table 4 Sl. number 40 33.26 26.51 20 13.26 6.74 – – – – 2 Interest charges 6.38 5.58 4.42 3.09 2.05 1.02 – – – – 3 O&M charges 0.81 0.81 0.81 0.81 0.81 0.81 0.81 0.81 0.81 0.81 4 Total fixed charges 6.98 6.51 5.11 3.91 2.86 1.84 0.81 0.81 0.81 0.81 5 Net kWh available 5 5.12 5 5 4.88 4.88 5 5 5 5 6 Cost of kWh generation 0.33 0.30 0.23 0.16 0.12 0.07 0.05 0.05 0.05 0.05 7 Cost of kWh adjustment 0.49 0.53 0.58 0.63 0.69 0.77 0.84 0.91 0.98 1.07 8 Cost of total generation 6.74 6.51 5.12 3.95 2.86 1.84 0.81 0.81 0.81 0.81 9 Total cost of adjustment 10.47 11.39 12.67 13.95 15.12 16.51 18.05 19.56 21.30 23.07 10 Profit 3.72 5.07 7.44 10 12.16 14.65 17.23 18.79 20.49 22.49 11 Repayment of loan 6.74 6.51 6.51 6.51 6.74 6.51 – – – – 12 Net profit/shortfall (10–11) –3.02 –1.58 0.81 3.26 5.49 7.91 17.23 18.79 20.49 22.49 277 Total capital cost Statement of cash flow for a period of ten years ($1 = 43 Rs.) 1 Prospects of wind energy in India ×104$ G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian 278 7 The policies for developing wind power A favourable fiscal/policy environment exists in India for development of wind power. The policies introduced by various state governments in India for private sector wind power projects are listed in Table 5. In this table, wheeling, banking, buy-back, third party sale, capital subsidy and other incentives of various states are given. These vary from state to state owing to different state-government policies. In the last ten years, wind power development in India has been promoted through Research and Development (R&D). The government subsidies and fiscal incentives are outlined below (Reliance Industries Ltd., 2002). Table 5 Policies introduced by the state governments for private sector wind power projects ($1 = 43 Rs.) Item Third party sale Capital subsidy Other incentives $0.05/kwh (5% escalation 1994–1995) Not allowed 20% maximum $58,140 Industry status 2% per month for 12 months $0.05/kwh (5% escalation 1994–1995) Allowed Maximum $58,140 for backward area No electricity duty for five years 2% of energy 6 months To be decided on case to case basis Not allowed – – Madhya Pradesh 2% of energy – $0.05/kwh (no escalation) Allowed Same as for other industries – Maharashtra 2% of energy 12 months $0.05/kwh (5% escalation, 1994–1995) Allowed 30% (Maximum $46,512) – Rajastan 2% of energy 12 months $0.07/kwh (5% escalation, 1999–2000) Allowed – No electricity duty for five years Tamilnadu 5% of energy 5% (2 months balance on 31st March to lapse) $0.06/kwh (no escalation) Not allowed – – State Wheeling Banking Buy-back Andhra Pradesh 2% of energy 12 months Karnataka 20% of energy West Bengal From central government • income tax holiday • accelerated depreciation • concessional custom duty/duty free import • capital/interest subsidy Prospects of wind energy in India • production tax credits • property tax credits • direct tax incentives • direct investment incentives • subsidised loans from IREDA • site prospecting, review and permission • renewable portfolio standard • green marketing/pricing. 279 From state governments • energy buy-back power • wheeling and banking facilities by State Electricity Boards (SEBs) • sales tax concession benefits • electricity tax exemption • capital subsidy (Windpro Monthly Journal, 2003f). The additional incentives for the setting up of wind farms are: • non-resident Indian participation in power projects • permission for duty-free import of components for the indigenous manufacture of turbines (Windpro Monthly Journal, 2002c). 8 Performance and Pareto analysis 8.1 Performance analysis A wind turbine is characterised by the coefficient of power Cp = f (λ ) , where λ is the tip speed ratio. The maximum value of Cp is 0.593 (Betz limit). The wind turbine generator has a rating and it cannot be operated beyond a certain limit. Hence at higher wind speed, wind machines are regulated to shed extra power. The performance of the turbine is different for different sites with the same cubic mean velocities. This is because of the variation in the Weibull parameters (scale and shape factor) of the two sites. The annual values of the scale factor and shape factor for the Muppandal site in Tamilnadu (in the southern part of India) are 2.2 and 27.7 respectively. The performance of a wind farm at the Muppandal site for a period of five years (April 1999–March 2004) had been analysed in this paper to rectify the deficiencies. The total installed capacity of the wind farm taken for this study is 16.525 MW, which consists of 53 wind electric generators. The wind farm has different capacities of WEGs, such as 225, 250, 400 and 750 kW. These WEGs were commissioned from 1993 to 1999 in six phases. G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian 280 The performance of the wind turbine is proportional to Wind Power Density (WPD). The monthly WPD is shown in Figure 12. This curve indicates the maximum WPD of 723.3 watts/m2 in the month of June. The annual WPD in this wind farm was 361 watts/m2. Satisfactory WPD were recorded from April to September in Muppandal. Monthly average wind power density in Muppandal Au gu st Se pt em be r O ct ob er No ve m be r De ce m be r Ju ly Ju ne M ay Ap ril 800 700 600 500 400 300 200 100 0 Ja nu ar y Fe br ua ry M ar ch Power density (watts/sq.m) Figure 12 Months The monthly generation of this wind farm for the period of April 2003–March 2004 is shown in Figure 13. It is found that the energy generation varies due to climatic, environmental and technical factors. Whereas from April to August it shows an upward trend, from August onwards it shows a declining trend. The upward trend is caused by good climatic factors and the downward trend is caused by technical and climatic factors. Figure 13 Monthly generation for 2003–2004 6000000 5000000 4000000 3000000 2000000 1000000 Months M ar ch Au gu st Se pt em be r O ct ob er No ve m be De r ce m be r Ja nu ar y Fe br ua ry Ju ly Ju ne M ay 0 Ap ril Generation (kWh) 7000000 Prospects of wind energy in India 281 The year-wise generation of the wind farm for the period April 1999–March 2004 is shown in Figure 14. It is found that there was a wide variation of generation over the years. The generation was at a maximum (3.9479557 × 107 kWh) in the year 2001–2002. The reasons were higher capacity factor (27.28%) and production time (380 154 hours). The average annual generation was 3.776963 × 107 kWh. The generation was at a minimum (3.5271718 × 107 kWh) in the year 2000–2001. Figure 14 Year wise generation (kWh) from 1999 to 2004 40000000 Generation (kWh) 39000000 39479557 38454269 38283475 38000000 37359132 37000000 36000000 35271718 35000000 34000000 33000000 1999-2000 2000-2001 2001-2002 2002-2003 2003-2004 Year The comparison of capacity factor, real and technical availability are computed and shown in Figure 15. A trouble-free wind farm will have a maximum of 100% technical availability. In this case the technical availability was steady and it was more than 95%. It was at a maximum (98.38%) in the year 2002–2003 and at a minimum (95.55%) in the year 2000–2001. The average technical availability was 97.46% for five years. Though this was excellent, owing to environmental disturbances, especially low wind, a reduction in average real availability resulted. It is observed that the wind farm had very low real availability in the year 2002–2003 owing to an increase in machine fault. The capacity factor was found to vary from 24.36% to 27.28%. The average real availability and capacity factor for five years were 81.22% and 26.23% respectively. There is scope for improvement in performance by improving the grid and machine availability. Figure 15 Comparison of TA, RA and CF 120 Percentage (%) 100 80 Technical Availability (TA) Real Availability (RA) 60 Capacity Factor (CF) 40 20 0 1999-2000 2000-2001 2001-2002 Year 2002-2003 2003-2004 G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian 282 Figure 16 shows the relationship between total production, stoppage and mission time. The summation of total production and stoppage time gives the total mission time. The stoppage time is the summation of downtime due to low wind speed, machine faults, maintenance works and grid problems of the wind farm. The average mission, production and stoppage time for five years were 464 788, 377 522 and 87 266 hours respectively. In the year 2003–2004, the total production time was greater, i.e., 387 178 hours, and the total stoppage time was less (78 374 hours.). The design of the wind turbine could be modified to operate at lower cut-in speeds so that downtime due to low wind can be reduced. Because of more downtime (94 688 hours) in the period 2002–2003, the wind farm experienced more failures. Distribution of Total Mission Time Figure 16 500000 450000 Time (hours) 400000 350000 300000 250000 Total Mission Time 200000 Total Production Time 150000 Total Stoppage Time 100000 50000 0 1999-2000 2000-2001 2001-2002 2002-2003 2003-2004 Year The total stoppage time due to various faults and low wind is computed and tabulated in Table 6. The average grid failure, low wind, control panel failure, electrical, mechanical and preventive maintenance time were 17 177, 66 395, 306, 2316, 55 555 and 1518 hours respectively. Its percentage distributions are shown in Figure 17 (pie charts). The percentage of failure due to the control panel was less and due to the grid was higher. The average percentage wind farm stoppage due to mechanical component, electrical and grid failure was 6.2%, 2.8% and 17.6% respectively. Table 6 Year-wise total stoppage time Mechanical failure time (hours) Preventive maintenance time (hours) Grid failure time (hours) Low wind time (hours) Control panel failure time (hours) Electrical failure time (hours) 1999–2000 10 590.05 66 181 546.1 2783.1 2000–2001 10 010.4 62 027 383.7 3348 2001–2002 40 378.4 65 854 181.4 1836.2 2002–2003 10 982.8 79 246 151.8 1602.8 2124.7 550 2003–2004 13 924.6 58 668 267.3 2007.5 2344.9 1161.6 Year 7658.6 716.8 10 457.4 4468.5 5190.9 693.3 Prospects of wind energy in India Figure 17 283 Percentage distribution of stoppage time Mechanical 9% Electrical 3% Control panel 0% Grid 12% Grid 12% Low w ind 74% Control panel 1% Preventive maintenance 1% Mechanical Electrical 2% 2% Preventive maintenance 1% 2002-2003 Low w ind 83% 1999-2000 Mechanical 12% Mechanical 3% Preventive maintenance 5% Grid 11% Electrical 4% Control panel 0% Preventive maintenance 1% Electrical 3% Control panel 0% Grid 18% Low w ind 68% Low w ind 75% 2000-2001 2003-2004 Mechanical Electrical 5% 2% Preventive maintenance 1% Control panel 0% Low w ind 57% Grid 35% 2001-2002 8.2 Pareto analysis Fault analysis had been done to identify the technical problems in the wind farm arising from grid, electrical and mechanical components. The Pareto diagram is one of the seven old quality circle tools used for solving problems. It classifies data and rank categories in descending order of occurrence to separate significant categories from trivial ones. It helps in prioritising the different categories taken into account for analysis. This also helps in identifying the minimum number of factors required to fulfil a function from a lot. The next advantage is getting the percentage reduction in the overall scenario when reduction is carried out in one or two of the factors. 284 G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian Even though one may desire solving all problems practically, it is not practical. Hence prioritisation is essential. For the problems identified, categorisation has to be made in terms of the extent of the damage they cause to the system. The percentage values can be used to find out the percentage reduction in the overall problems, when one or two of the prioritised problems are solved. The Pareto charts before and after the problem-solving exercise are shown in Figures 18, 19, 20 and 21. Six stoppage time factors, i.e., low wind, grid failure, mechanical, electrical, preventive maintenance and control panel time, for five years were identified and their percentage of stoppage time were 71.18%, 18.42%, 5.95%, 2.48%, 1.63% and 0.34% respectively. If grid failure, mechanical and electrical problems are solved completely, 18.42%, 5.95 and 2.48% respectively of problems in the wind farm will be over. Pareto chart before problem solving 350000 300000 250000 200000 150000 100000 50000 0 120 100 80 60 40 20 0 Low wind Grid Mechanical Electrical Preventive Control maintenance panel Cummulative frequency (%) Frequency (%) Figure 18 Category Reduction of 50% mechanical problems 120 100 80 60 40 20 0 350000 300000 250000 200000 150000 100000 50000 0 Low Wind Grid Mechanical Electrical Preventive Control maintenance panel Category Cummulative frequency (%) Frequency (%) Figure 19 Prospects of wind energy in India Reduction of 50% fault in grid Frequency (%) 350000 100 300000 80 250000 200000 60 150000 40 100000 20 50000 0 0 Low wind Grid Mechanical Electrical Preventive Control maintenance panel Cummulative frequency (%) Figure 20 285 Category Reduction of 50% electrical fault 120 100 80 60 40 20 0 350000 300000 250000 200000 150000 100000 50000 0 Low wind Grid Mechanical Preventive Electrical maintenance Control panel Cummulative frequency (%) Frequency (%) Figure 21 Category This analysis can also be extended to find out the reduction in problems when more than one problem is tackled partially. If 50% of the failure time due to grid, mechanical and electrical problems is removed, the overall reduction in the frequency of stoppage will be 9.22%, 2.97% and 1.24%, respectively, which is significant. If the various problems of the wind farm due to mechanical components such as gear, yaw gear, blade, brake assembly, hydraulic components, electrical components and grid-related problems are tackled, the performance of the wind farm will improve considerably. The turbine faults should be reset immediately after the machine is stopped. This will increase the machine availability. 286 9 G.M.J. Herbert, S. Iniyan, E. Sreevalsan and S. Rajapandian Conclusion A detailed report is given about the prospects of wind energy generation in India. A total wind power capacity of 2485.9 MW has been installed, which is about 1.7% of the total installed capacity of electricity in the country and about 14.6% of the exploitable/technical potential. In India, there are 65.415 MW demonstration projects and 2418 MW private projects installed in 11 states with 7013 numbers of WEGs. The total generation from wind power projects established in various states in India is 14.174 × 109 kWh. It is concluded that India can generate more power from wind if a larger number of wind-monitoring stations are established and selection of wind-farm sites with suitable wind electric generator and improved maintenance procedure of wind turbine to increase the machine availability are insured. It is further concluded that the advanced wind turbine technologies and favourable policies from the Government of India will facilitate and accelerate wind energy generation. It is also concluded that India can confidently count on wind power as an energy source if the issues are correctly addressed. The performance of the 16.525 MW installed capacity wind farm at Muppandal has been analysed. 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