1.0    Wind Energy Development in Tamil Nadu and Andhra Pradesh, India
2.0    Simple Solar Water Heater for Developing Countries
3.0    Some plants to promote afforestation and sustainable development
4.0    Article 4
5.0    Article 5
6.0    Article 6

Tamil Nadu state has the distinction of 719 MW capacity windfarms at the end of September 1998 out of the country’s total figure of 992 MW. Andhra Pradesh has 59 MW installed windfarms in the state. 1995-96 saw a boom when 282 MW windfarms were set up in Tamil Nadu and 39 MW capacity in Andhra Pradesh. Subsequently there was a steady decline in the windfarm development in both the states. This case study attempted in detail to trace the reasons for the boom and the factors that contributed to the slump in windfarm activity in the states. The role of institutions in determining the effectiveness of National and Regional public-sector initiatives to promote and disseminate wind energy in the two states is discussed in the paper. The study has also looked into the financial, technical, transaction and institutional barriers which inhibit the diffusion of wind energy in the states. Creation of Wind Fund, establishment of co-operative windfarms, setting up of wind estates, linking generation to incentives for optimum production, promotion of reliable water pumping windmills and wind battery chargers for small scale applications suggested in the paper for rapid growth of wind energy in Tamil Nadu and Andhra Pradesh. The results of the case study may be used to improve public policy intervention in disseminating wind energy in the country. It may also be relevant to multilateral and bilateral aid agencies in their projects and / or programmes to promote cost-effective wind energy technology dissemination in developing countries.

Keywords: Wind energy; Institutional barriers; windfarm cooperatives

Renewable Sources of Energy have a vital significance in the context of growing concern about sustainable energy supplies and protection of the environment from adverse effects of fossil fuel utilisation. The current pattern of energy consumption and the growing energy requirements on account of development, economic growth, population increase etc., are considered to be essentially unsustainable. The staggering increase in oil import burden, the crippling effects of power shortage and the deterioration in environmental quality are some of the critical issues facing India today.

Worldwide, vast amounts of carbon-di-oxide and other greenhouse gases that are being dumped into the atmosphere by fossil fuel burning and other economic activities are causing grave concern about the possible global warming and attendant consequences. It is becoming increasingly clear that any effective strategy to contain global warming must involve rational and efficient use of energy and a gradual transition from reliance on fossil fuels to alternative, environment friendly energy technologies. A major component of this strategy will admittedly be the promotion of renewable energy systems in a big way, and in this scenario, wind energy is expected to figure prominently. Among the renewable energy sources, wind is the most matured one.

The advantages of harnessing wind energy include:
· wind energy is available free
· the production and use of wind energy does not pollute the atmosphere
· it does not cause acid rain and contribute to the greenhouse effect which leads to global warming
· a windfarm irrespective of its size has a low gestation period
· for every 1 Kwh of electricity generated by wind, the emission of CO2 is reduced by 1 Kg
· the operation of a wind turbine weighing 50 tonnes saves the annual burning of 500 tonnes of coal
· the primary energy used to produce a wind turbine is recovered in about a year · wind is available during day and night

Early Efforts in India to Tap Wind Energy

In India wind energy was first tapped in the 1950s for its potential to pump water for domestic use and irrigation as an alternative to diesel/electric pumpsets. Wind pumps were imported on a modest scale and installed on an experimental basis at a number of sites. A National Water-Pumping Windmill Demonstration Programme was subsequently introduced by the Government of India during the 6th (1980-85) and 7th (1986-91) plan periods and about 2800 units of the 12-PU-500 wind pumps for shallow well water pumping were installed around the country. In addition, over 200 indigenously developed gear type pumping units have also been installed in 9 states under an Operational Research Programme (ORP). Unfortunately due to various technical and non-technical reasons, the 12-PU-500 could not succeed except in some regions.

A Wind Resource Assessment Programme was taken up in 1985 comprising wind monitoring, wind mapping and complex terrain projects. The programme covered 25 states with over 600 stations. Eighty three masts of 20-25 meter height with sophisticated continuous wind data recording instruments, and 172 masts of 5 meter height with cup counter anemometers were set up in the country. Five volumes of Wind Energy Resource Survey for India have been published so far which cover wind data from 198 wind monitoring stations
(1-5).
The programme for demonstration windfarms was initiated in 1985. Since 1992 private investors/developers took lead in setting up commercial wind power projects in the country. Since Tamil Nadu state has become the leader in windfarm installations in the country an attempt is made to study in depth the factors that contributed to the early growth and the pitfalls that led to the slump including institutional barriers besides a comparative study with wind power developments in Andhra Pradesh, a neighbouring state.

A package of incentives have been offered by the Central Government such as accelerated depreciation, tax holiday, soft loans, custom and excise duty reliefs, liberalised foreign investment procedures etc., Private investors/developers took advantage of these incentives and set up windfarms.

The list of wind sites with their latitudes and longitudes annual mean wind speeds and annual wind power density measured at 20/25 m height and extrapolated to 30 m height in Tamil Nadu and Andhra Pradesh are given in Table 1.




The wind energy potential and the resources exploited till the end of September 1998 are shown in Table 2.



(a) assuming 0.5 per cent of land availability for Wind Power generation in potential areas.
(b) as on 31.03.98, assuming 20 per cent grid penetration.
(c) as on 30.09.98
Source : MNES

State -wise and year-wise wind power capacity addition (MW) in India is shown in Table 3.




Source : MNES

The power production state-wise and year-wise in the country through windfarms upto September 1998 is shown in Table 4.




Table 1 clearly indicates that most of the windy sites occur in the Tamil Nadu state like Muppandal, Edayarapalayam, Poolavadi, Kethanur etc.,
From Table 2 it is evident that the bulk of Windfarm installations are in Tamil Nadu.
An analysis of Table 3 reveals that there was a steady increase in windfarm activity from 1992-93 to 1995-96 followed by a sharp decline.

Initiatives and Policies that led to Windfarm boom in Tamil Nadu

· good windy sites like Muppandal were available at that time
· the sites were nearer to towns for accessibility to bring labour and to provide accommodation to personnel involved in the projects
· the sites were well interlinked with highways
· grid Network by Tamil Nadu Electricity Board (TNEB) was well connected and mostly passing through the sites
· active promotional steps by TNEB, TEDA (Tamil Nadu Energy Development Agency) and local authorities
· boom in Textile market and Cement Industry where huge profits were earned and hence Tax concessions were availed by setting up Windfarms. Moreover these industries need heavy power and as such windfarms came handy for captive power consumption · power cuts during summer months was an handicap for industries. Incidentally during summer months wind energy generation was at its peak. It supplemented the TNEB power supply position
· most of the wind turbine manufacturers were situated in Tamil Nadu and as such the investors/developers are confident of supply of the machines and after sales service of the machines
· TNEB took the first step to set up windfarms at sites like Muppandal, Kayathar and Kethanur proving the viability of windfarms thus inducing confidence among private wind farm developers
· since the land at the identified windy locations is privately owned, the purchase and acquisition of the land was quick without any hitch
· Chennai port having excellent facilities for import of heavy machinery of Wind Turbine Generator (WTG) components like Blades facilitating intra-state transportation
· TNEB extended all facilities for private entrepreneurs like consultancy services, processing of the application for issuance of No Objection Certificate (NOC), CEIG (Chief Electrical Inspectorate to the Government) clearances, extending grid connection to windfarms and executing new dedicated sub-stations. Above all TNEB has established an effective system for registering the energy generation by each wind turbine and enabling the wind turbine owners to either adjust their energy bill thereof, or effecting payment to those who sold power generated to TNEB
· TNEB officials assigned to wind energy field were professionally qualified, well knowledgeable and as such executed the job well

Factors which led to steady decline in Windfarm activity in Tamil Nadu.
· due to unplanned addition of windfarms at sites like Muppandal, Kayathar, Poolavadi etc., led to inadequate capacity at dedicated substations resulting in shutting down of wind turbines even during peak wind speed periods--loss of generation and hence revenue loss to the WTG owners
· connecting WTGs to weak and rural feeder lines in the absence of dedicated substations at some windfarm sites, poor grid -- poor generation -- loss of revenue
· TNEB imposing penalties for excess RKVAH comsumption
· improper maintenance of WTGs by some suppliers during warranty period and by owners beyond warranty
· inadequate facilities by some manufacturers of WTGs at sites for repairs as well as at their works. This led to long delays and breakdown periods --loss of generation
· rotor blade failures in some cases due to manufacturing defects as well as lightning strike
· disregard for earthing regulations and lightning protection leading to unduly large breakdown of control systems resulting in very expensive repairs and long break down periods
· reduction in tax concessions led to corresponding reduction in tax benefits to investors to put in windfarms
· introduction of Minimum Alternate Tax (MAT) further eroded the gains of setting up Windfarms.
· slump in Textiles and Cement business activity
· liquidity crunch
· difficulties in availing loans from banking institutions
· disproportionate hike in interest rates subsequently imposed by IREDA for loans to set up windfarms
· the earlier irrational policies of importation led to substantial numbers of unworthy and uncertified machines resulted in failures of some models which cast aspersions in the minds of investors about the technology itself. As a result the market for wind turbines dramatically shrunk leaving even the genuinely good technology machines in trouble
· applying windspeed data from limited number of anemometers (two for 300 MW in Muppandal) resulted in wide variation from predicted wind turbine generation and actual generation creating doubts about the viability of wind projects.

Barriers to Wind Energy Development<BR>
Although subsidies and financial incentives were given liberally to wind energy, this technology remained marginalised in the over all energy scenario. Wind energy contributes about 1 per cent of the total power available in the country. While working out cost-benefit analysis and calculating internal rate of return for any power project, hidden or indirect subsidies on pricing a resource and infrastructure were never taken into account in the case of conventional energy sources. On the other hand, economic analysis of wind energy projects rarely supported their economic justification. Most projects were supported for their renewable nature, social and environmental benefits. There are number of instances which clearly demonstrate the need to create a level playing field enabling wind energy to compete with conventional energy in India.

Financial barriers

Lack of adequate financial resources has been a chronic problem for setting up wind energy projects. In India, Indian Renewable Energy Development Agency Ltd (IREDA) played a crucial role in supporting wind projects in the country. IREDA’s lending terms are presented in Table 5.


Category - Financing Guidelines for Wind Farm Developers:


Source : IREDA

Bilateral development institutions from Netherlands, Denmark and loan from Global Institutions like the World Bank through IREDA also contributed for the boom in wind energy projects in Tamil Nadu.

There is the need to create more financial institutions to support wind projects. A wind fund of Rs. 1000 crores (1 crore = 10 million, 1 US $ = Rs. 42) on the lines of the one in UK can be created in India to support wind projects exclusively. Such a fund will provide equity finance for small-scale wind energy projects and will offer investment opportunities to individuals and institutions alike.

Transaction barriers

Transaction barriers to wind energy are similar in many ways to those in developed and developing countries (6-11). In India many of the sources of risk, institutional structures and conditions, experience and skills deficiencies are unique. The result is greater uncertainty in transactions about opportunities, costs, and benefits.

Technical barriers

Lack of standardisation in system components resulting from the wide range in design features and technical standards, and absence of long-term policy instruments have resulted in manufacturing, servicing and maintenance difficulties of wind turbines. The mismatch between locally manufactured components and imported parts resulted in weakening the reliability of the over all system, in some cases. The absence of effective servicing and maintenance networks, combined with inadequate user-training, resulted in a loss of confidence among entrepreneurs and customers. Another barrier is lack of co-ordination among research groups, academic institutions and private wind industry.

Institutional Barriers

These constitute the real constraint, not only to the development of Renewable Energy Sources like wind but also to their wider dissemination. Technologies that are of immediate relevance in a developing country like India are now available and, while improvements may be required in individual cases, especially to reduce production costs, the hardware for harnessing wind energy is relatively well known and reliable. What is required is therefore an appropriate institutional infrastructure capable of planning and implementing a co-ordinated programme at all levels and of mobilising community support for it at the micro-economic levels where it would be implemented. This strategy calls for a different approach that would need to be compartmentalised according to the sources of energy supplies and yet to be integrated and co-ordinated to bring the results to the masses. This new strategy will require an integrated institutional approach involving political will to support it consistently, institutional arrangements to implement it and involvement of the people to sustain it (12).

Wind energy is being pushed in India because of its usefulness as decentralised energy system. Its introduction initially generated a good deal of interest from the scientific perspective rather than its potential to meet energy demands on decentralised basis. A growing gap in demand and supply, environmental considerations and the decentralised nature of wind projects made everyone in India realise its significance in meeting the growing energy demand to some extent. Initially, wind projects were promoted in India as panacea for all unsolved energy problems. The main emphasis on wind projects was on the target achievement rather than on consumer satisfaction of capacity building. Little efforts were made to strengthen the institutions involved in the diffusion of wind energy, or provide an enabling environment to the entrepreneur to promote the commercialisation process. This resulted in raising undue demands and expectations that wind energy is unable to fulfill.

A multiplicity of agencies has resulted in duplication, overlapping and coordination problems in the implementation of the wind projects. Multiplicity of agencies has also resulted in unnecessary delays. A bureaucratic structure with a target-oriented approach has led to rigidity in instructions and a centralised planning process that is the opposite of the decentralised nature of wind energy. Most of the decisions are still taken at the central level with little flexibility given to the field agencies and grass roots level institutions.

Training Programmes in Wind Energy

Development and successful implementation of a complex technology like wind energy requires sufficient information and inputs of manpower. It is imperative that energy education including wind should be included at various levels in schools, colleges and universities and other academic institutions. Regular four year bachelor degree course in wind energy specialisation will be useful in the design, development and evaluation of this emerging technology.

Windfarm co-operatives in India -- need of the hour

In India most of the windfarms are set up by big industries mainly as a tax shelter plan. Unless the wind projects are mass based, it is hardly possible to get the political support besides resources to set up wind projects. On the other hand the wind developments in Denmark where the installed capacity at the end of July 1998 stood at 1259 MW are worth emulating in Tamil Nadu (India). About 75 per cent of the wind turbines in Denmark are owned by local associations and private individuals (13). More than 100,000 families are involved as share holders. Over the past decade, the popularity of wind turbines has grown to such an extent that today they cater for 7 per cent of the country’s total electricity consumption. This, inturn, provided an excellent basis for renewed community spirit and the growth of interest in energy and environment
matters.

Another success story that needs close examination is the phenomenal success of wind energy in Germany which has been relegated to the top position in the world with installed capacity of 2390 MW at the end of July 1998. The wind energy boom in Germany is mainly due to the renewable energy feed in tariffs (REFITs) granted there, apart from investment grants given initially, and some research activities. All private producers of electricity from renewable energy are statutorily granted a fixed price which the utilities are obliged to pay. The price is calculated on the basis of the average electricity rates in Germany (14).

Some suggested policy changes to boost windfarms in Tamil Nadu

In India currently accelerated depreciation is allowed on wind projects. The main aim of extending this incentive to windfarm owners and developers is that they supplement power to conventional one. Unfortunately in majority of the cases this liberal incentive has ended merely as a tax shelter plan. This has far reaching consequences on the generation of power by wind turbines. It is hightime that the Government seriously considers to link depreciation benefits to generation of power so that the wind turbines produce optimum power.

There is wide variation in the incentives offered by different state governments, Table 6.



* Policy expired on 31.03.98.

It is hoped that Tamil Nadu Government introduces third party sale as well as sales tax benefit like Madhya Pradesh which will go a long way in setting up of Windfarms on a large scale in the state.

Water pumping windmills in Tamil Nadu

In Tamil Nadu about 850 water pumping windmills were installed out of which 120 were geared type deep well wind pumping systems. The rest were 12-PU-500 type with 12 bladed pumping unit with 500 cm. diameter rotor fitted to the windmill. The performance of 12-PU-500 windmills has not been satisfactory due to variety of reasons like improper siting and installation, lack of user awareness, design problems, substandard material usage in the fabrication of windmill to bringdown the cost and an improper implementation strategy (15). As wind pumping is a well established technology that offers on alternative to diesel and electric pumpsets, and since there are many areas with good wind regime in Tamil Nadu, water pumping windmills will be a boon to conserve electricity (which is heavily subsidised for agricultural purposes) which can find application in other areas.

It is hoped that MNES will promote reliable and sturdy windmills for irrigation in the country in general and Tamil Nadu in particular.

Wind Battery Chargers for small applications

Wind energy generators can also charge batteries which can store energy for lighting, radio communication, hospital equipment and to power various emergency-related equipment. In India about 50 wind chargers were installed on a pilot scale. Their performance has not been satisfactory. Today over 100,000 wind chargers are working in Inner Mangolia and studies indicate that levelised costs of off-grid, household scale renewable energy systems are cost-competitive with conventional gasoline gen-sets and pv/wind hybrid systems appear to be an economic means of providing year round electricity service and meeting the rising energy demands of remote households in Inner Mangolia (16-21).

Tamil Nadu offers best sites to supply power in a decentralised way to charge batteries through wind.

Wind Energy Developments in Andhra Pradesh

In Andhra Pradesh the installed capacity of Windfarms stood at 57.79 MW at the end of September 1998. About 50 MW of this capacity is at Ramagiri. From Table 3 it can be seen that 1995-96 saw a boom with installations totaling 38.9 MW with sharp decline subsequently as happened in Tamil Nadu.

Reasons for slow progress of windfarms in Andhra Pradesh

· in Andhra Pradesh the land for setting up windfarms used to be allotted by NEDCAP.

There was undue delay in the process of acquiring the land as well as allotting it. Windfarm developers who want to avail tax benefits were unable to meet the deadline because of delay in the allotment of land. Though Andhra Pradesh was estimated to have 1200 MW wind capacity, the land alienation has become a stumbling block for the progress of windfarms. However recently the policy of land allotment has been changed and now the Government is allotting land at the market price. The District Administration has been empowered to give advance clearance for land to set up windfarms in the state

· Ramagiri has complex terrain. The Consultants and Manufacturers of wind turbines overestimated the generation at Ramagiri based on the wind data from 3 anemometers. The actual generation fell by about 25 percent from estimated generation. This led to doubts in the minds of the investors on the viability of wind projects in Andhra Pradesh.

A case study of 5 numbers of 500 KW wind turbines of a windfarm at Ramagiri revealed wide variation in percentage of generation with reference to 576 level from 24.22 per cent to 7.79 per cent (22)

Generation details with contour levels at a windfarm in Ramagiri



Source : (22)
The variation of about 4 per cent of energy between locations 4 and 5 is due to the slope of terrain in the predominant wind direction eventhough both are at the same contour level. This proves beyond doubt that critical micrositing is a must to set up windfarms especially in complex terrain areas.

In complex terrain wind data has to be obtained from an anemometer close to the site where windfarms are to be set up. In California during ‘80s there was one anemometer per 150 to 350 turbines or 10-20 MW while in the ‘90s one anemometer for every two or three 200 KW machines or 0.5 MW capacity (23,24).

Such an approach is needed in the Andhra Pradesh context

· introduction of MAT as well as increase in the interest rates charged by institutions like IREDA contributed to the slowing down of wind activity in Andhra Pradesh
· local problems led to the closure of windfarms for some period at Ramagiri. However the intervention of the Government helped to restart the windfarms there.

Some progressive measures initiated by NEDCAP to boost windfarms

NEDCAP (Nonconventional Energy Development Corporation of Andhra Pradesh Ltd), Nodal Agency responsible for the promotion of renewable energy sources in Andhra Pradesh has taken effective steps to have a 33/220 KV substation with a ring structure exclusively for evacuating power from the windfarms at Ramagiri.

Since most of the identified sites in Ananthapur District in the state are having hilly region, NEDCAP has undertaken contour survey of all the potential areas at 3 meters intervals (25).

Another innovative concept initiated by NEDCAP is Wind Estate mainly to assist the small developers in acquiring land and in the procurement of machinery at reasonable prices, erection, operation and maintenance by NEDCAP on behalf of small developers. Work is on to set up 20 MW wind estate at Kadavakallu by NEDCAP.

Wind projects of capacity 50 MW are underway in Andhra Pradesh mainly at Kadavakallu, Tallimadugula and Bhimunipatnam.

Introduction of sales tax benefits will help to attract investors to set up large windfarms in Andhra Pradesh.

In Andhra Pradesh 320 waterpumping windmills were installed but their performance was far from satisfactory. It is hoped both MNES and NEDCAP will promote efficient windmills for irrigation besides wind battery chargers for small applications in Andhra Pradesh.

Conclusions and prognosis

The case study of wind energy developments in Tamil Nadu and Andhra Pradesh reveals that incentives like depreciation, tax holiday, customs and excise duty reliefs should continue for some more years until the wind projects sustain on their own. There is a dire necessity to continue wind data studies by setting up more anemometers/windmasts and that too at varying heights of 20,30,40 and 50 meters to get accurate wind data rather than relying on extrapolated figures. Latest methods like Geographical Information Systems (GIS) have to be utilised for large - area screening of prospective sites for wind power development. Wind speeds at the height of a wind turbine depend strongly on terrain elevation, exposure, slope, and orientation to prevailing winds, all factors which can be calculated from a GIS - based Digital Elevation Model (DEM). In addition, with the appropriate database, a GIS can account for other factors that affect wind site suitability, such as the distance to nearby transmission lines, proximity to protected areas, and type of vegetation cover. The cost of the wind turbines has to be brought down considerably by indigenising the components.

Thorough micrositing is a must by competent experts which will enable the investors to choose the best site and matching it with the suitable machines for optimum generation. The Central Government in co-operation with different State Governments can fix uniform incentives for a healthy growth of windfarms in the country. Creation of a wind fund and peoples participation through windfarm co-operatives will give a fillip to the declining wind activity in the country in general and Tamil Nadu and Andhra Pradesh in particular. Before permitting wind projects, the respective State Electricity Boards should ensure that suitable evacuation facilities through a dedicated substation and stable grid are in place. For optimum generation of energy by windfarms, depreciation and other incentives should be coupled to generation of energy rather than mere tax shelter plan. A remunerative price based on the ever increasing tariff by conventional sources should be fixed for wind energy generated electricity which will enable faster growth of windfarms. Since Tamil Nadu and Andhra Pradesh have strong agricultural base, water pumping windmills which are reliable will be a boon to conserve energy as a supplementary to electric and diesel pumpsets in windy areas. The Central and State Governments of Tamil Nadu and Andhra Pradesh should promote water pumping windmills on a large scale. Wind battery chargers have also a role to play in the states of Tamil Nadu and Andhra Pradesh for small scale power applications. The Centre for Wind Energy Technology(C-WET) coming up in Chennai and the Wind Turbine Test Station at Kayathar in Tamil Nadu through DANIDA assistance are expected to fill the gap of setting and ensuring standards to maintain quality in wind turbines.

To achieve Ninth Plan (1997-2002) targets in power, an average 9000 MW per year is required to be put up in the country. With improved design wind turbines, financial package, political will to support large wind projects through public sector undertakings and a remunerative price for wind generated electricity, it is hoped that wind energy will play a supplementary role to meet the growing power demand in the country in general and Tamil Nadu and Andhra Pradesh in particular.

Acknowledgments

This is a joint research project with Centre for International Climate and Environmental Research-Oslo (CICERO) and financially supported by the Research Council of Norway. The author is thankful to Dr. Lin Gan of CICERO for his useful suggestions.

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