The Tamil Nadu Energy Development Agency (TEDA) is a Nodal Agency of the Ministry of New and Renewable Energy (MNRE), Government of India for the promotion of Renewable Energy schemes in the State. It has been registered as a society under the Societies Registration Act and is functioning since 1985. It is under the administrative control of Energy Dept.

TEDA has set the following as its main objectives.

Identification and potential estimation of renewable energy in the State.

Create awareness on the potential and prospects for use of renewable energy.

Enhance renewable energy contribution in the overall energy mix in the State Grid.

Abatement of Green house gas emissions caused from increasing use of conventional fuels by promoting the use of renewable energy / stand alone systems to combat Global Warming.

Development and implementation of sustainable energy security policy towards attaining energy independence in small villages.

The installed capacity of power generation in Tamil Nadu from the Renewable Energy sources, which was 3834 MW as on 31.3.2007 has now reached 4115 MW as on 29.02.2008 representing about 37% of the country’s capacity. About 98% of this capacity has come from the private sector. The major contribution is from Wind which is 3711 MW (50% of the country’s capacity). The others are Bagasse based Co-generation 213 MW, Biomass Power 99 MW and small hydro (upto 25 MW) 87 MW. Totally 6570 million units of electricity was generated from the renewables resources in the state during the year 2006-07, which is about 10% of the grid consumption. Tamil Nadu’s achievements of 27% in installed capacity and 10% in the units generated as share of renewables resources is way ahead of other States and even the country as a whole, as these were the targets set to be achieved by 2012 and beyond.

Tamil Nadu has been in the forefront, in producing power from the Renewable Energy sources such as Wind, Biomass etc. and feeding to the Grid supplementing the conventional power. During the 10^th Five year Plan period (2002-2007), it has increased from 1000 MW to 3834 MW, which is 27% of the TNEB’s grid capacity, much higher than the target of 10% set by the Government of India to be achieved by 2012. The percentage at the all India level is at present only 8%. The addition made during the year 2007-08 is 281 MW as on 29.02.2008.. In the present day context, everyone is most concerned about Global Warming and climate change, it is commendable that the State of Tamil Nadu has achieved such a high percentage of Renewable share in the Grid Power on par with other Developed Countries of the World.

Wind has considerable potential as a global clean energy source being both widely available, though diffuse, and producing no pollution during power generation, Tamil Nadu is endowed with three lengthy mountain ranges on the Western side with potential of 1650 MW in palghat pass in Coimbatore District, 1300 MW in Shengottai pass in Tirunelveli District and 2100 MW in Arelvaymozhi pass in Kanniyakumari District and 450 MW in other areas totalling 5500 MW.

There are 41 Wind potential sites in 8 Districts in the State, declared by MNRE, as suitable for Wind Power projects based on the Wind assessment studies carried out by TEDA with the funding assistance of MNRE and the State Government. Wind farms have so far been set up in 26 sites of the above, almost entirely by the private sector, except for 19 MW of Demonstration Wind farms in 8 locations set up during 1986 to 1993, jointly by TEDA and TNEB, but now run and maintained by TNEB. The total installed Capacity of Wind Mills in the State including the 19 MW under public sector is 3475 MW (7349 Machines) as on 31.3.2007. The addition made during the year 2007-08 is 236 MW as on 29.02.2008. The capacity addition made during the 10^th Five year Plan (2002-07) is given below:

The total units generated from wind are 20682 million units (cumulative) as on 31.3.2007 and for the year 2006-07 it was 5269 million units which is 8.5% of Tamil Nadu’s grid consumption. In recognition of Tamil Nadu’s commendable achievement in Wind power generation, the State was awarded the First prize for Wind power programme (2002-2007). The award was presented during the Silver Jubilee Function of MNRE by Tmt. Pratibha Devisingh Patil, Hon’ble President of India on 22.11.2007. Further for the first time in the country, a village Panchayat Odanthurai in Coimbatore District, has set up a wind mill of 350 Kw capacity exporting power to grid, which was commissioned on 31.3.2006.

A package of incentives which includes fiscal concessions, custom duty, excise duty exemption and 10 year tax holiday are available for Wind Power projects from Govt. of India. Intra State open access regulations have been notified and preferential tariff orders issued for Wind Power Projects in Tamil Nadu by the Tamil Nadu Electricity Regulatory Commission (TNERC). As per the revised tariff orders issued in May 2006, the rate is Rs.2.75 per unit for the projects for which agreements had already been signed and Rs.2.90 per unit where the agreements are to be signed. The wheeling and banking charges remain unchanged at 5% each. The new unit rates have now come into effect as per the TNEB order dt.14.9.2007.

Wind resource assessment studies were carried out in 69 Wind prone Zones by setting up Wind monitoring stations since 1986, out of which 41 sites having annual mean wind speed of 18 KM per hour and above and annual mean Wind power density of 150/200 W/m² and above at 30 m/50m level, have been declared by MNRE as potential and viable for commercial projects. Windmills have so far come up in 26 sites. 9 new wind-monitoring stations are under installation through C-WET a Govt. of India undertaking (one completed) in various Districts with 20% cost sanctioned by the State Govt. and balance 80% cost provided by MNRE to C-WET.

Further Micro survey of Wind resource, around select potential stations has been carried out to provide reliable data to wind farm developers for selecting proper location for Windmills in potential areas. Apart from 19 stations where the study was carried out with MNRE funding, the study was done in 8 more stations by C-WET with State funding. The total potential in the 27 stations as per the above study is 6385 MW.

Apart from MW scale wind mill generators (grid connected), stand alone type generators upto 30 KW rating are also available. Wind mills can also be used directly for pumping water for drinking purposes or minor irrigation. MNRE subsidy is available for installation of these systems.

Biomass is produced by green plants through photosynthesis using sun light. Biomass contains organic matter which can be converted to energy and replenished by human effort. The estimated power generation potential from surplus Biomass in Tamil Nadu is 487 MW as per the District level study carried out by Anna University with MNRE funding. Another 450 MW is available from Bagasse based Co-generation in sugar mills.

Energy can be produced from biomass through gasification as well as combustion route. In combustion route, biomass is burnt fully to produce steam which in turn is used for power generation through turbines. In gasification process, biomass is burnt partially and converted into producer gas which is used for thermal or electrical applications.

The cumulative installed capacity of grid interactive biomass and bagasse based Co-generation is 474.60 MW as on 29.02.2008 (375.60 MW from Bagasse Co-generation + 99 MW from Biomass Power). In the case of Co-generation projects, the total exportable surplus power, after their own consumption of sugar mills is 213 MW.

In the case of Biomass Power projects, 32 Projects with total capacity of 328 MW, recommended by the standing Committee constituted by the Government under the Chairmanship of CMD / TEDA, are in the various stages, out of which 5 projects (39.7 MW) are likely to be commissioned soon, apart from 7 projects (87 MW) already in operation.

A package of incentives which includes fiscal concessions such as accelerated depreciation, concessional customs duty, excise duty exemption, income tax exemption on projects for 10 years etc are available from Government of India for these power projects. Since December 2006, Capital subsidy in lieu of interest subsidy is being provided by MNRE for grid interactive renewable energy projects (except wind in private sector) through concerned financial institutions, after the project has been successfully commissioned. In the case of bagasse Co-generation, projects in Co-operative / public / Joint Sector sugar mills, 50% of the subsidy amount will be released to the Financial Institutions after sanction of loan and the balance after successful commissioning. As per the Tamil Nadu Electricity Regulatory Commission, tariff orders issued in May 2006, the rate for purchase of power by TNEB is Rs.3.15 per unit with concessional wheeling charge of 3% for distance upto 25 KM and 6% for distance beyond 25 KM.

Generation of wastes both in solid and liquid form is associated with industrial and other activities. Civic activities generate solid and liquid wastes while industrial activities mainly generate liquid wastes. Both types of wastes can be used for producing energy through different processes namely Biomethanation and combustion.

Biomethanation is the most preferred route for recovery of energy from Biomass wastes having higher moisture and organic content. Organic wastes segregated from Municipal solid waste, sewage water and other industrial wastes with high levels of Biological oxygen demand (BOD) / Chemical oxygen demand (COD) can be treated in this method. Combustion technology is used for producing steam from Municipal solid wastes that contain high amount of organic non-bio degradable matter and low moisture content. The steam so produced is used for power generation through conventional turbines. MNRE subsidy is available for all these schemes. Power purchase agreement can also be made with TNEB for export of the power produced. There are 3 projects with total capacity of 4.25 MW in operation in the State including 250 KW at Koyambedu Vegetable complex.

In order to promote the use of Solar Energy for producing grid quality power in the country, the Ministry of New and Renewable Energy (MNRE), Government of India, has introduced new policy guidelines in January 2008, whose salient features are given below:

For the first time, generation based incentives would be provided for grid interactive solar power generation. A maximum amount of Rs.12.00 per Kwh would be provided as incentive for electricity generated from solar photovoltaics and Rs.10.00 per Kwh for electricity generated through the solar thermal route and fed to the grid from a power plant of 1 MW capacity and above. This incentive will be provided to the project developers at a fixed rate for a period of ten years for the projects which are commissioned by 31^st December 2009. This incentive will be available for all the existing registered companies, Central and State power generation companies and public / private sector photovoltaic power project developers who have set up or propose to set up a registered company in India. The maximum capacity per project will be 5 MW either through a single project or multiple projects of a minimum Capacity of 1 MW each. Each State may be allowed to set up upto 10 MW under this programme. These projects are to be undertaken on Build, Own and Operate basis.

Based on the above, TEDA has sent a proposal to the State Government, to invite ‘Expression of interest’ from the interested project developers for putting the grid inter-active solar power plants in Tamil Nadu. The power generated from these plants will be purchased by TNEB at the rate to be decided by the Tamil Nadu Electricity Regulatory Commission.

Further, in order to know about the recent developments in the field of Solar Power Generation, the State Government has deputed the Chairman and Managing Director of Tamil Nadu Energy Development Agency and also a Senior Engineer from TNEB, who is now on deputation, as General Manager in Tamil Nadu Energy Development Agency, to visit Spain and Germany, where a number of such power plants are in operation. The officials, besides visiting some of these plants, will hold discussions with the Government agencies and other firms there about the possibility of any joint ventures with them by the State Government / TNEB for setting up of Solar Power Generation projects in Tamil Nadu.

The one great advantage of Renewable energy is that it can be generated wherever it is required with locally available sources such as Solar, Wind, Biomass etc. It thus reduces the burden on the centralized generation systems in the grid involving long transmission with consequent losses. TEDA encourages installation of these systems by the industries, institutions and local bodies with subsidy provided by the Government of India (MNRE) or the State Government or both. A brief outline on the various systems available is given below:

Solar thermal systems harness the heat energy from the sun, through Solar thermal collectors using specially coated black metal plates and use the same for heating of water or air. Solar Water heating system, Solar air heating system / dryer and Solar Cookers are some of the best examples of Solar Thermal systems in use.

A Solar Water Heater is a device that uses heat energy of the sun to provide hot water for various applications such as bathing, Washing, Cleaning etc in homes as well as Hotels, Hospitals and other industries where hot water is required. A domestic Solar Water Heater, with a Capacity of 100 LPD (liters per day), is sufficient for a family of 4 or 5 members. It can easily replace a 2 KW electric geycer and can save upto 1500 units of electricity a year. It pays back the cost in 3 to 5 years, after which hot water is available almost free of cost during the remaining life span of the systems, which is about 15 – 20 years. Any higher capacity systems as required can be installed in multiples of 100 LPD. The only condition is a shadow free open space is required at the ground or terrace. About 3 sq.m space is required for 100 LPD system. It works automatically and one does not have to operate any part of the system.

In view of its inherent advantages, the State Government had made the use of Solar Water heating system mandatory in certain types of new buildings in the State in the year 2002, by amending the building bylaws.

The Government of India (MNRE) is providing soft loan @ 2% to domestic users, 3% to institutional users not availing accelerated depreciation and 5% to industrial / commercial users availing depreciation through IREDA and Public / Private sector banks etc. Capital subsidy equivalent to upfront interest subsidy @ RS.1100/- per sq.m of Collector area will be available to registered institutions and Rs.825/- per sq.m. of Collector area to registered Commercial establishments that do not avail soft loans.

The State Government had also earlier provided subsidy to domestic and institutional users for installing the Solar Water heating systems. But now, it has been restricted to providing 100% cost for installation in Government institutions. Every year, a few Government Hostels / Hospitals have been provided with these systems. For the year 2007-08, the State Government has sanctioned Rs.10.00 ,lakhs for installing systems of total Capacity of 5000 LPD in Government Hostels / Hospital buildings. Apart from this, at the instance of Hon’ble Minister for Electricity, and as per the announcement made in the Legislative assembly, installing of Solar Water heating systems in the residences of Ministers, High Court Judges, State Guest House, MLA’s Hostel, MLA’s Quarters and special houses for IAS & IPS Officers at Government Estate has been proposed at an approximate cost of Rs.2.00 Crores. As on 31.3.2007 of Solar Water Heating System have been installed in 61 Government buildings, 3522 residences for domestic purposes and 440 industries / Institutions for commercial purposes under various subsidy schemes

In the Solar Air Heating system or Solar dryer also, the sun’s heat energy is used to heat the air which is made to blow over the materials to be dried. A raise in ambient air temperature of 30 to 40^oC can be obtained and the usage of conventional fuels such as firewood, coal etc can thus be reduced to the extent of 25%. The Solar Air Heating systems are being used in processing of tea leaves, fruits, vegetables and drying of grains etc and the same has been extended to drying of fish, cloth, salt, spices, leather etc. The uniform heating obtained through the use of Solar Air Heating systems, improves the quality of the dried items.

The Government of India (MNRE) is providing subsidy for installation of Solar Air Heating system at 50% of the cost of the system, subject to a maximum of Rs.2500/-per sq.m of Collector area for non-profit making institutions, organisations and 35% of the cost subject to a maximum of Rs,1750/- per sq.m. of collector area for commercial and industrial users.

The State Government also had provided subsidy for installation of 32 systems with a total Collector area of 498 sq.m in the years 2003-04 and 2005-06 when the Government of India subsidy was not available. Totally 46 systems with a total Collector area of 4575 sq.m have been installed under subsidy schemes.

A Solar Cooker is a device that uses heat energy from the sun to cook food. Two types of Solar Cookers are available viz box type and dish type. A box type Solar Cooker, suitable for a family of 4 or 5, can cook food in 2 to 3 hours. The Cooker has to be kept outside in the Sun, and can cook upto 4 items at a time. It is available with electrical backup, so it can be used even in non-shine hours. It can save upto 4 LPG cylinders a year. However food cannot be fried in the box solar cooker. There is no Government subsidy for this type of Solar Cooker. However, under arrangements made by the Government of India (MNRE), interest free loan is available for the bulk users through IREDA and some of the banks.

A dish Solar Cooker can cook food in lesser time than a box cooker. It can be used even for preparing chappaties and for frying. It can however, be used to cook only one item at a time. The Government of India (MNRE) subsidy is available upto 30% of the cost. The State Government also sanctioned an amount of Rs.2.40 lakhs for providing 40 Nos. Solar Dish Cookers at full cost to Noon Meal Centre / Hostels during the year in 2006-07. The same was allotted to the Most Backward Class and Denotified Communities Welfare Department Student Hostels.

Solar steam cooking system are also available which can be installed where boilers are used for steam generation and the food cooked for thousands of persons. Such a system installed in Tirupathy temple is working well.

Solar energy is converted into electricity through solar photovoltaic (SPV) Cells / modules and utilized to operate various electrical appliances.

SPV devices can be used for meeting the needs of home lighting, office lighting and Street lighting and promoted in the State under Government of India (MNRE) scheme with subsidy upto 50% of the cost. Local bodies in rural and urban areas can avail this subsidy and reduce the recurring Electricity charges.

The Government of India (MNRE) allotted to Tamil Nadu in 2006-07, 4000 Nos. SPV Home lighting systems and 900 SPV Street lighting systems which have been allotted to various districts through District Collectors for implementation under the subsidy scheme. No allotment has been made for the year 2007-08, pending finalisation of XI Five Year Plan proposals by the Government of India. Totally 5647 Nos. SPV Street lights, 1236 SPV Home lights and 285 SPV pumps have been installed in the State under the subsidy scheme.

Under Part-II scheme for 2007-08, the State Government has sanctioned Rs.10.00 lakhs for providing 5 Nos. Solar Operated Vaccine Refrigerators @ Rs.2.00 lakhs to Primary Health Centres in remote areas to make available the essential Vaccines and life saving medicines to the needy people. The scheme is under implementation.

Tamil Nadu has achieved total electrification of villages long time ago. But there are still a few remote habitations in forest areas which could not be electrified due to problems of long distance, forest clearance etc. Based on the list of habitations furnished by TNEB, which might not be electrified through grid, the Government of India (MNRE) sanctioned the RVE phase-I programme for electrification of 150 remote habitations using Solar lighting systems. The cost of which including 5 years maintenance is to be shared by the Central and State Governments. The work has been completed in March 2007 by providing 5190 Nos. SPV Home lighting and 283 SPV Street lighting systems in 128 habitations in 12 Districts at a total cost of Rs.8.25 crores. Some of the other habitations were subsequently electrified by TNEB.

Further under Phase-II, it is proposed to take up electrification of another 74 habitations in 6 Districts, after obtaining sanction of Government of India (MNRE). When this scheme is implemented, Tamil Nadu will achieve the distinction of completing electrification of all unelectrified remote habitations in Tamil Nadu as identified by TNEB.

Biomass gasification is basically conversion of solid biomass such as wood, wood waste, agricultural residues etc., into a combustible gas mixture normally called producer gas. They can be utilised for thermal and electrical applications. The required biomass yield can be obtained from energy plantations grown on wastelands. Further all types of agricultural wastes viz Rice husk, Coconut shells, briquettes of various agricultural residues, maize crops branches and twigs of plants are the possible fuel stocks for the Gasifier.

Government of India (MNRE) Provides subsidy for these gasifiers as below:

Biogas is a flammable gas and is used as fuel. It is technically possible and economically feasible to generate biogas from cattle dung, agro waste, Kitchen waste, sugarcane, pressmud etc. and also human waste. It is the most appropriate option for meeting the growing energy needs in rural areas. It is a clean and convenient fuel for cooking and lighting in households and also for power generation in KW scale.

The Government of India (MNRE) subsidy is available for installation of Biogas plant upto Rs. 5.00 lakhs / project or 20% of the project cost. MNRE has sanctioned 2 Nos. biogas based power generation systems, one of 10 KW capacity and another 5 KW capacity to be installed in Coimbatore and Salem Districts respectively by self Help Groups. The power generated will be utilized for electrification of tribal areas.

The State Government also provided subsidy at 30% of cost for installation of Toilet linked Biogas plants in institutions and Women sanitary complexes in Panchayats. Totally 20 Nos. in institutions and 41 Nos. in Panchayats were installed during 2003-04 and 2004-05 through the DRDA.

Small hydro power projects upto 25 MW capacity has been brought under the purview of MNRE, Government of India due to their benefits particularly concerning the environment and their ability to produce power in remote areas. They are economically viable and have a relatively short gestation period. TNEB is dealing with these projects in the State along with the large hydro projects.

Micro Turbines in KW range are now available indigenously which can be installed in small canals, streams, river systems located in remote places to generate power for captive use. This will encourage small entrepreneurs to set up manufacturing / processing units providing livelihood and economic development for the local people. Hence the State Government sanctioned Rs.10.00 lakhs @ 2.00 lakhs per system for installation of 5 Nos. 5 KW micro turbine, in suitable Village Panchayat during 2007-2008. The scheme is under implementation.