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Read this essay to learn about the renewable sources of energy found in India.
Renewable Energy Technologies (RETs) are increasingly being viewed as an equitable and environmentally sound way of addressing the energy concerns in the country—low per capita energy consumption, inequalities in access, supply constraints, growing dependence on imports and high environmental costs.
Rural energy demand still to a large extent is met by non-commercial energy sources such as firewood, cattle dung and crop residues. The real cost of using these fuels—in terms of time spent in collection, storage and preparation, the health implications of indoor air pollution caused by the use of these fuels; and potential environmental damage caused by deforestation and desertification, and global warming—is extremely high.
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Over the last few years, the technical, operational and economic viability of RETs has led to a surge of interest in their applications. RETs can contribute substantially towards meeting grid and off-grid energy needs. Several technologies for grid connected power generation such as using wind; small hydro and biomass are proven technologies which are in large scale application in the country.
In addition, RETs offer possibilities of distributed generation is sparsely populated or far-flung areas where extension of the grid may be unviable. A niche area for RETs is a range of thermal applications both in rural and urban centers. Applications such as solar air and water heating systems, solar cookers, solar buildings, as well as energy recovery from urban, industrial and agricultural wastes are becoming popular in urban, semi-urban and rural centers.
Hydroelectric sources, by far, are the predominant source of renewable energy in India. India’s 10th Five-Year Plan, which runs through 2007, calls for 10% of all new electric generating capacity to come from renewable energy sources, and almost all of this will be hydroelectric.
Of the other forms of renewable energy, wind and biomass are the most likely to have any significant input to India’s power generating mix. The Indian Renewable Energy Development Agency, which is a part of the Ministry of Non-Conventional Energy Sources, oversees development of these non-hydro renewable energy sources.
There are twenty river basins, major and minor, in India. The largest of these, in terms of area, is that of India’s largest and longest river, the Ganges (known in India as the Ganga) and its major tributary the Yamuna. The Ganges flows southeastward along the foothills of the Himalaya mountain range until it enters Bangladesh and then turns southward to empty into the Bay of Bengal.
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Other major Indian rivers include the Narmada (India’s largest westward-flowing river), which flows through central India into the Arabian Sea, and three eastward- flowing rivers, the Godavari, the Krishna, and the Cauvery, which flow through southern India into the Bay of Bengal.
Besides these, there are two other major rivers which pass through India—the Indus, which rises in Tibet and flows northwestward through the northern state of Jammu & Kashmir before entering Pakistan, and the Brahmaputra, which also rises in Tibet and flows southwestward through the eastern Indian states of Arunachal Pradesh and Assam before entering Bangladesh and joining the Ganges.
India has vast hydroelectric resources. Some estimates place the hydroelectric potential as much as 150,000 MWe, with another 90,000 MWe possible for pumped storage capacity. About one-fifth of India’s total electricity generation now comes from hydroelectric power plants. There are many, many players in India’s hydroelectric subsector—22 different ownership entities are involved in the 67 hydroelectric facilities that are of at least 100 MWe in capacity.
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The most important hydroelectric generator, though currently not the largest in terms of generating capacity, is probably the National Hydroelectric Power Corp. (NHPC), which was created in 1975 with the mandate to develop India’s hydropower potential. NHPC presently owns and operates nine hydropower facilities, ranging in size from the 545 MWe Chamera I power Plant in Himachal Pradesh state to the 5 MWe Kalpong Power Plant in the Andaman & Nicobar Islands; its total generating capacity is presently 2,180 MWe, but only 80 MWe of that has come online since 1996.
The Bhakra Beas Management Board (BBMB) is presently India’s largest-capacity hydropower generator. It was created in 1966 to manage the supply of water, in Himachal Pradesh State, from the Sutlej and Ravi-Beas rivers whose waters flow into Punjab, Haryana, Rajasthan, and Delhi. BBMB presently operates six hydroelectric facilities, with a total generating capacity of more than 2,800 MWe, including the two power plants at Bhakra dam whose combined capacity is 1,300 MWe.
Three other government-owned entities that generate hydroelectric power are the North Eastern Electric Power Corp. (NEEPCO), the Tehri Hydro Development Corp. (THDC), and the Satluj Jal Vidyut Nigam Ltd. (SJVN), each of which owns and operates large amounts of hydro generating capacity.
And besides these, there is also the Damodar Valley Corporation (DVC), which was created in 1948 and modeled after the Tennessee Valley Authority; the DVC owns less than 150 MWe of total generating capacity in Jharkhand State (with no facility more than 80 MWe) but has the mandate of also managing flood control, irrigation, and water supply for parts of West Bengal and Jharkhand States.
In addition to these Indian government-owned entities, many of the state-owned SEBs also own electricity generating assets. The largest of these is the Andhra Pradesh SEB, whose hydroelectric assets are nearly equal in total capacity to those of BBMB. Other SEBs with large amounts of hydroelectric capacity is Tamil Nadu, Kerala, and Maharashtra, whose Koyna facility is presently the largest hydroelectric power plant in India.
Electricity subsector reforms are now causing the spin-off of SEB assets into somewhat more independent entities. An example of this is the Uttar Pradesh Power Corporation Ltd. (UPPCL), which came into existence in January 2000 with the mandate to plan and manage the supply, transmission, and distribution of electricity in the State of Uttar Pradesh. All of the UPPCL generating assets had formerly belonged to the Uttar Pradesh SEB.
Further reform, in 2001, split the UPPCL generating assets into two new companies, the Uttar Pradesh Rajya Vidyut Utpadan Nigam Ltd. (UPRVUNL), which has control of the UPPCL’s thermal-electric power plants, and the Uttar Pradesh Jal Vidyut Nigam Ltd. (UPJ VNL), which controls the UPPCL’s hydroelectric power plants.
To complicate the situation even further, the State of Uttaranchal was split off from Uttar Pradesh in November 2000, and a new entity, the Uttaranchal Jal Vidyut Nigam, Ltd. (UJVNL) has now assumed control of all of UPJVNL’s assets that are in Uttaranchal. Similar though less complicated situations exist elsewhere in India.
In the State of Orissa, the Orissa Hydro Power Corporation (OHPC) was created to operate the Orissa SEB’s hydroelectric assets while the Orissa Power Generating Corporation (OPGC) was given control of the SEB’s thermal-electric generation assets. And in the State of Karnataka, the SEB assets there were given over to the Karnataka Power Corporation, Ltd. (KPCL), while in the State of Andhra Pradesh, SEB assets now belong to the Andhra Pradesh Power Generation Corporation.
There is a huge amount of additional hydroelectric generating capacity that could come online in about the next ten years; at least 30 projects of more than 100 MWe are in the construction stage and many more than that are in various stages of planning.
In particular, the Narmada River and its tributaries are undergoing rapid development; the Narmada Valley Development Plan envisions 30 large dams, more than 100 medium-size dams, and about 3,000 small dams. If all of these are built, the river system would in effect be transformed into a series of lakes.
The largest of these are the Sardar Sarovar and Indira Sagar (also known as the Narmada Sagar) hydroelectric facilities, both currently nearing completions. Even larger is scale will be the hydropower development by NHPC on the Dihang (also known as the Siang), Siyom, and Kamla Rivers in the Brahmaputra river basin of Arunachal Pradesh state in eastern India. Six large power plants are envisioned, which will add nearly 30,000 MWe generating capacity.
The largest of these will be the 11,000 MWe Dihang Upper project, which, when completed in about 2012, would become the world’s second largest power plant (behind the Itaipu hydropower plant in Brazil). NHPC, with more than 3,600 MWe of new hydroelectric capacity under construction and at least another 25,000 MWe in planning stages, is positioned to become the dominant hydropower player.
NEEPCO is also active, with six projects of at least 100 MWe in planning stages. Of all the private power developers becoming involved in hydroelectric projects, Jaiprakash Industries, based in New Delhi, has the most capacity under construction and in planning.
India is also actively pursuing smaller hydroelectric power generation opportunities. More than 1,400 MWe of generating capacity is now online that consists of hydroelectric facilities of 25 MWe and less, with about another 500 MWe in construction stages.
The Indian Ministry of Non-Conventional Energy Sources, the controlling entity, now considers small hydro a success story of sufficient commercial interest that it has allowed the SEBs to allot about another 2,000 MWe for development by the private sector.
Most parts of India get 300 days of sunshine a year, which makes the country a very promising place for solar energy utilization. So far, photovoltaic (PV) generation has been limited to very small installations, but throughout the country there are more than 750,000 of them, generating a total of about 58 MWe.
Most of these are standalone installations, for applications such as pumping water for irrigation, but there are 17 grid-interactive PV installations that supply a total of about 1.4 MWe to the electricity grid during daylight hours. PV is thought to have promise in isolated rural areas, where access to electricity via power lines is not available. There are plans for additional PV power plants in India; the largest of these would be two 60 MWe PV facilities in Bihar State (at Gaya and Chakai), which would be sponsored by the Bihar SEB.
One other solar power project worth mentioning is the 140 MWe hybrid solar-thermal combined-cycle gas turbine projects, now in the advanced planning stage, which would be built in the Jodhpur district of Rajasthan.
The solar-thermal energy component, which would utilize a parabolic mirror trough collector, would account for 35 MWe of the total generation; the steam from the solar-thermal component would be combined with steam from a heat recovery steam generator from the gas turbine component of the project to generate electricity in a conventional Rankine steam cycle. This would be the first commercial project of its kind in the world.
The Indian Government is also promoting direct use of solar energy, in the form of solar water heaters and solar cookers. The cookers are large parabolic reflector-based systems that are meant to meet the needs of small, isolated communities, but so far they have not found widespread acceptance.
Solar water heaters are doing better, and have seen use at hotels, hospitals, textile mills and other industries, and dairies. There has also been some use in individual residences. Nearly 500,000 sq. mts. of conventional solar flat plate collectors are now in use throughout India.
The Solar Thermal Energy Programme seeks to tap solar energy for thermal applications such as water heating, cooking, drying, space heating, distillation, power generation and solar passive architecture. Solar water heating can be used to meet the energy needs for heating water in homes, factories, and other commercial and institutional establishments.
The collector area installed so far in India for water heating is around 5,50,000 sq. mt. Solar water heaters are now being manufactured on a commercial scale with an annual production of over 50,000 sq. mt. of collector area. The sale of solar cookers is one of the oldest programmes related to renewable energy. Around 0.5 million solar cookers have been sold in the country.
Solar air heating can be used to meet energy requirements for space heating during winter months and to meet process heat requirements in industries and agriculture. So far, around 4500 sq. mt. collector area has been installed in the country for space heating. The objective of solar buildings programme is to promote energy-efficient building designs with optimum use of available solar energy and other forms of ambient energy in the management of energy needs of buildings.
India has abundant wind resources to harness for power generation. Strong seasonal winds blow across the Indian subcontinent April through September. The Ministry of Non-Conventional Energy Sources has estimated that the gross wind-power potential of India is about 45,000 MWe and has identified more than 200 sites suitable for wind-power facilities. Southern India in particular has excellent wind resources, with the States of Gujarat, Andhra Pradesh, Tamil Nadu, Karnataka, Kerala, Madhya Pradesh, Maharashtra, and Rajasthan having the highest potential.
India ranks fifth in the world in the number of wind power installations; wind power installed capacity is now more than 1,700 MWe with almost all of the capacity located in the southern half of the country. India’s wind-power generation is mostly not yet making use of the most modern large-scale technology; wind power farms in India are made up of numerous small units, each generating, in effect, only an incremental amount of electricity.
The lone exception is Suzlon Energy Ltd.’s Vankusawade Wind Park, located on a high mountain plain above the Koyna reservoir in Maharashtra State, which uses 350 kilowatt wind generators. The Vankhusawade Wind Park is presently the world’s largest wind power facility.
There are seven main geothermal regions in India, which contain a total of about 400 thermal springs. The major geothermal area is the Son-Narmada-Tapi (SONATA) rift zone, which follows the Narmada river valley from Gujarat into Madhya Pradesh, and then continues into eastern India. An additional place of interest is Barren Island in the Andaman Islands, which has the only active volcano on the Indian subcontinent.
The State of Gujarat seems to be the hub for geothermal activities in India. The Gujarat State Government passed a resolution theoretically aimed at creating incentives for geothermal and other forms of renewable energy, but any actual effect has been minimal and there remain significant financial barriers.
Despite this, there are some geothermal pioneers. Avin Energy Systems Ltd. of Ahmedabad has been exploring the possibility of building a 5 MWe geothermal power generating plant in Gujarat as a demonstration that geothermal energy can be commercially successful. Avin believes that the geothermal potential of Gujarat alone could support about 1,000 MWe in generating capacity.
Geothermal energy in India is presently mostly being used for direct heating applications such as heating of bathing pools and drying of agricultural produce. For power generating purposes, the overall geothermal potential of India is about 10,000 MWe. The Geological Survey of India (GSI) has developed an atlas identifying more than 300 potential sites for generating power.
The Ministry of Non-Conventional Energy Sources estimates India’s energy potential from biomass at nearly 20,000 MWe, with 16,000 MWe from biomass and 3,500 MWe from cogeneration (i.e., combined heat and power) plants using bagasse from sugar mills. About 40 cogeneration projects capable of generating 280 MWe and 30 biomass projects capable of generating 140 MWe have been commissioned.
Nearly 500 MWe of additional generating capacity is under construction. Besides its use for power generation, biomass is also a large component of the energy mix in poor households. These include firewood, agricultural residues and cow dung, and are used mainly for heating and cooking.
The national programme on energy recovery from wastes offers the multiple benefits of reduction of urban and industrial waste, abatement of environmental pollution and production of energy. The Ministry of Non-conventional Energy Sources is currently implementing two programmes in this area. One is the national programme on recovery of energy from urban and industrial wastes and the other on development of high rate biomethanation processes to reduce the emission of greenhouse gases.
Since its inception, the Ministry of Non-conventional Energy Sources has been promoting the development of other forms of energy namely chemical, ocean and hydrogen. The Ministry has been supporting a number of Research & Development projects sanctioned to various scientific institutions, universities, CSIR laboratories, and industries.