Renewable energy resources are mostly biomass-based and are available in unlimited ... Renewable energy sources are inexhaustible, i.e. they can be replaced after ..... the list in providing 32% of all the primary energy use in the country.
An Assignment on
ALOK KUMAR CHANDRAKAR M. Phil Environment & Sustainable Development Central University of Gujarat, Sec. 30, Gandhinagar 0
Energy Resources: Indian Scenario 1. Introduction Energy can be defined in a number of ways. In the broad sense, energy means the capacity of something – a person, an animal, or a physical system (machine) – to do work and produce change. It can be used to describe someone doing energetic things such as running, talking, and acting in a lively and vigorous way. It is used in science to do describe the part of the market where energy itself is harnessed and sold to consumers. Today, energy is the primary input for almost all economic activities and has become vital for improvement in the quality of life. Infact, the whole infrastructure rests upon energy. The energy consumption of a nation now-a-days is usually considered as an index of its development. About 24 percent of energy consumed globally, is used for transportation, 40 percent for industries, 30 percent for domestic and commercial purposes and the rest 6 percent for other uses including agriculture. There is a wide disparity in energy consumption in developed and industrialized countries and developing countries. About 2 billion people, one third of global population living in developing countries, lack access to adequate energy supplies. Three billion people depend upon fuel wood, coal, charcoal, dung and kerosene etc. for cooking and heating. On the other hand, industrialized nations, with only 25 percent of global population, account for 70 percent of the commercial energy consumption. India, with 16 percent of world’s population, accounts for just 3 percent of the total energy consumption. For a 100 units consumed by an American citizen for transportation, a Japanese consumes 30 units and an Indian consumes only 2 units. The case is more or less similar with other developmental activities. India is an agriculture country. Majority of its population lives in village and uses wood, agricultural wastes, livestock dung etc. as energy source. In urban areas, in industries, transportation, telecommunication, domestic establishment etc., the energy consumed is derived from oil, coal, natural gas, hydroelectricity or nuclear power. The industries claim a large share (about 38.5 percent) of the total energy followed by transportation (about 31.2 percent), domestic establishment (about 13.7 percent) and the rest in agriculture. Share of various energy sources in the commercial consumption of energy in India mostly comes from the coal (about 56 percent) and petroleum (about 32 percent). The other sources are hydroelectric, nuclear power, natural gas etc. Economic growth, increasing prosperity and urbanization, rise in per capita consumption, and spread of energy access are the key factors that would be responsible for substantially increasing the total demand for electricity. Thus there is an emerging energy supply-demand imbalance. According to Central Electricity Authority (CEA) report, the anticipated energy and peaking shortage in the country was estimated to be 10.3 percent and 12.9 percent, respectively, in 2011 and 2012. 1
The modern civilization is much dependent on energy availability but the energy resources, mainly oil, coal, natural gas and hydroelectric power are becoming scarce and costlier. The prices of oil, the most common source of energy, are going very high. To cope with ever increasing demand, efforts are being made to develop new approaches in conventional and nonconventional energy sources and new measures of energy conservation. 2. Energy Resources Like other natural resources, energy resources are also renewable as well as non-renewable. A) Renewable Energy Resources: Renewable energy resources are mostly biomass-based and are available in unlimited amount in nature since these can be renewed (i.e. regenerated in natural process) over relatively short period of time. Renewable energy sources are inexhaustible, i.e. they can be replaced after we use them and can produce energy again and again. These include, firewood (or fuelwood) obtained from forest, petroplants, plant biomass (as agricultural wastes like bagasse), animal dung, solar energy, wind energy, water energy (hydro-electrical, ocean wave and tidal energy), and geothermal energy etc. These can reproduce themselves in nature and can be harvested continuously through a sustained proper planning and management. B) Non-renewable (Exhaustible) Energy Resources: Non-renewable energy resources are available in limited amount and develop over a longer period of time. As a result of unlimited use, they are likely to be exhausted one day. These include various fossil fuels including petroleum products, coal and natural gas and nuclear energy. Nuclear energy is mainly obtained from the nuclear fission of the uranium and thorium. The global resources of fossil fuel and uranium and thorium are limited and will be eventually be depleted. Moreover, use of fossil fuels for energy has negative environmental consequences, such as air pollution, global warming, acid rains and oil spills. Thus, it has been become essential to minimize the use of fossil fuels and to replace them with renewable resources.
Energy sources are also classified as Conventional and Non-conventional sources. A) Conventional Sources of Energy
The sources of energy which have been in use for a long time, e.g., coal, petroleum, natural gas and water power. They are exhaust able except water. They cause pollution when used, as they emit smoke and ash. They are very expensive to be maintained, stored and transmitted as they are carried over long distance through transmission grid and lines. 2
B) Non-Conventional Sources of Energy
The resources which are yet in the process of development over the past few years. It includes solar, wind, tidal, biogas, and biomass, geothermal. They are inexhaustible. They are generally pollution free. Less expensive due to local use and easy to maintain.
Energy Sources
Conventional Sources
Non-Conventional Sources
Coal
Solar energy
Oil and Natural Gas
Wind energy
Thermal power
Ocean (Tidal) energy (Water)
Firewood (Fuelwood)
Wave energy (Water)
Hydropower
Geothermal energy
Nuclear (Nuke) energy
Bioenergy (Biomass)
Keeping in view, the growing energy needs, use of non-conventional energy sources, over conventional should be promoted. A brief account of the various conventional and nonconventional sources of energy with special reference to Indian scenario is presented as follow. 3. Conventional sources of energy The conventional sources of energy are generally non-renewable sources of energy, which are being used since a long time. These sources of energy are being used extensively in such a way that their known reserves have been depleted to a great extent. At the same time it is becoming increasingly difficult to discover and exploit their new deposits. It is envisaged at known deposits of petroleum in our country will get exhausted by the few decades and coal reserves are expected to last for another hundred years. Along with the coal, petroleum and natural gas, electricity is conventional source of energy, which is playing a barometer of a nation's economic well-being. Availability of abundant electricity means unrestricted growth of industries, transport and agriculture. Depending upon raw material used, various types of electricity are hydroelectricity, thermal electricity (steam, gas, oil) and nuclear electricity. 3
3.1 Coal Coal is one of the most important sources of energy and is being used for various proposes such as heating of housed, as fuel for boilers and steam engines and for generation of electricity by thermal plants. Coal has also become a precious source of production of chemical of industrial importance coal is and will continue to be the mainstay of power generation in India. It constitutes about 70% of total commercial energy consumed in the country. Coal was formed around 255-350 million years ago, during the Carboniferous age, in hot damp regions of the earth. The plants and animals that occurred during this period, along the banks of rivers and swamps, got buried alive or after their death into the soil and due to heat accompanied by pressures gradually got converted into peat and coal over a millions of years of period. Partially decomposed vegetation deeply buried in sedimentary environments slowly transformed into solid, brittle, carbonaceous rocks commonly known as coal. The coal is mainly of three types: anthracite (hard coal), bituminous (soft coal) and lignite (brown coal). There properties are discussed in Table -1. Table - 1: Types of Coal Type of coal Lignite Sub-bituminous Bituminous Anthracite
%C (Carbon) 60-70 75-83 78-90 92-98
%O (Oxygen) 16-18 14-15 9-10 2-3
Volatiles %
% Moisture
Calorific Values
45 40 20 05
35 17 06 01
5000-6000 6100-6500 6600-7500 7500-8100
The coal is the most abundant fossil fuel with a total recoverable resource of about 6000 billion tones in the world. With present rate of consumption, the coal reserves are likely to last during next 200 years and if the use rate increase by 2 percent per year, then it will last within next 65 years. China is the leading producer of coal followed by USA. In India, coal occurs in rock sequences mainly of two geological ages, namely, Gondwana, little over 200 million years age and in Tertiary deposits which were found at a much later geological epoch (about 55 million years) ago. The major resources are located in central and eastern parts of the country. In India, the major coal fields are Raniganj, Jharia, Bokaro, Singrauli, Panch-Kanham (Tawa valley), Talchar, Chanda- Wardha and Godavari valley in states of Jharkhand, Orissa, West Bengal, Madhya Pradesh, Andhra Pradesh and Maharashtra. The proven coal reserves of the country as on January 1, 2005 is 247,847 million tones, the highest proven amount being 35417 million tones in Jharkhand. About 65 % of coal produced in India is used to produce electricity and rest in industries and for other purposes.
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On burning, coal produces heat which is converted into various forms of energy by different technologies. At the same time it produces several air pollutants including carbon dioxide which is a green house gas and causes global warming. Beside, there are many problems with coal use. It has to be mined from underground or from the surface. Underground mines besides being dangerous, cause several damages to the environment and lung diseases in the miners. In addition, coal releases huge amount of radioactive particles into the atmosphere which are harmful to human beings. 3.2 Oil and Natural Gas a) Crude oil or Petroleum It is believed that petroleum has been formed over a period of millions of years through conservation of remains of plants, animals and microorganism, living in sea, in hydrocarbon by heat, pressure and catalytic action.
Fig. 1 – Crude Oil
Petroleum is a clear fuel as compared to coal as it burns completely and leaves no residue. It is also easier to transport and use. Petroleum is largely used in transportation, operating water lifting engines, generators etc. Crude oil or petroleum, the lifeline of global economy, is contained mainly in 11 countries forming OPEC (Organization of the Petroleum Exporting Countries). About 70 percent of the global petroleum reserves occur in these countries. Of these, Saudi Arabia alone has one fourth of the oil reserves. OPEC was formed in 1960 with the purpose of jointly regulating the production and control of the price of the exported oil. Currently it has country member namely Algeria, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Quatar, Saudi Arabia, UAE and Vanezuela. OPEC discussions have a major impact on world oil price which largely depends upon political factors, global demand and the production politics of the organization. In India, crude oil was first recovered from Makum in North East Assam. Later, drilling for crude oil was done at Digboi, Dibrugarh, Narharkatiya and Surma valley in the north east. The oil field also lies around Bay of Cambay, Gujarat. The most important achievement was the exploration of oil in Bombay High on the continental shelf of Maharashtra, located at a distance of 167 km north-west of Mumbai. Recently oil has been located on the off-shore area of the deltaic coasts of Godavari, Krishna, Cauvery and Mahanadi. Oil prospects in India are not so high as coal. But the demands are very high and the country has to import oil from OPEC countries at higher rates. Indian oil reserves are about 4.45 billion tones out of which about 1257 million tones are recoverable. Since 483 million tones have been extracted, the recoverable balance is now about 774 million tones which shall last within next 25 years with the condition that crude oil production rate of about 30 million tones per year is maintained. 5
b) Natural Gas Natural gas, a fossil fuel gift from nature, is composed of methane (96 %) with small amounts of propane and ethane. Natural gas deposits often accompany oil deposits or may occur independently. It is the cleanest source of energy among fossil fuels. Natural gas can easily be transported through pipelines. It has a high calorific value and burns without any smoke. Natural gas can be used as a source of energy for domestic or industrial use. It can be used for power generation and as a raw material for petrochemical industries and fertilizer plants. It results as a byproduct during crude oil refining and from fractional distillation plants. About 40 percent of total natural gas is found in Kazakhistan, Russia. India has a huge reserve of natural gas of which a large amount flares up due to lack of adequate storage, compression and transportation facilities as a result about 17 million cubic meters of gas a day is wasted or burnt. Now the gas is distributed from Bombay High to Rajasthan, Gujarat, Madhya Pradesh and Utter Pradesh by a 1730 km pipeline, the HaziraVijapur-Jagdishpur pipeline. A similar pipeline is proposed for South India to feed the natural gas of Bombay High and the gas imported from West Asia to southern states. A gas grid is also proposed for Assam. LPG: Liquefied Petroleum Gas (LPG), widely used as a domestic fuel for cooking, has its main content as odourless butane to which other gases like propane and ethyl mercaptan are added to give fowl smell to identify leakage. It is obtained by converting petroleum into liquid from under pressure. CNG: Compressed Natural Gas (CNG) is used as an alternative to petrol and diesel for transport of vehicles. CNG is a cleaner fuel than diesal, used currently in many cities and long distance transport across the country. It contains mostly methane, compressed to 80 atmosphere. It is an ideal cleanest burning alternative fuel. 3.3 Thermal Power Thermal power plants use coal, petroleum and natural gas to produce thermal electricity. These fossil fuels are exhaustible and polluting. Electricity is the most convenient and versatile form of energy. This is in great demand in industry, agriculture, transport and domestic sectors. In thermal power plant, fossil fuel is blown into the combustion chamber of a boiler where it is burnt at high temperature (Fig. ). The hot gases and heat energy produced converts water – in tubes lining the boiler – into steam. The high pressure steam is passed into a turbine containing thousands of propeller-like blades. The steam pushes these blades causing the turbine shaft to rotate at high speed. A generator is mounted at one end of the turbine shaft and consists of carefully wound wire coils. Electricity is generated when these are rapidly rotated in a strong magnetic field. After passing through the turbine, the steam is condensed and returned to the boiler to be heated once again. 6
Fig. 2 - Thermal power plant The electricity generated is transformed into the higher voltages (up to 400,000 volts) used for economic, efficient transmission via power line grids. When it nears the point of consumption, such as our homes, the electricity is transformed down to the safer 100-250 voltage systems used in the domestic market. Both, big and small power stations are scattered all over the country. Electricity produced by them is fed into regional grids. It is proposed to have a single national grid. Improvements continue to be made in conventional thermal power station design and new combustion technologies are being developed. These allow more electricity to be produced from less coal - known as improving the thermal efficiency of the power station. Efficiency gains in electricity generation from coal-fired power stations will play a crucial part in reducing CO2 emissions at a global level. 3.4 Firewood (Fuel wood) Firewood (biomass) is a used as energy source since historical time. It is widely used for cooking and heating. In our country more than fifty per cent of the energy used by villagers comes from fire wood. It may be seen that nearly 70 % of the firewood demand pertains to the rural areas. Only 50 Mt. of the fuel wood may become available from natural resources. According to a report, for next 15 years or so the average fuel wood contribution from natural forest would be 0.75 t/ha/yr and the rest is to be met from the plantations. Whole of the required plantations is to be non-agricultural land, degraded forest land, culturable waste land, barren/inculturable land, permanent pasture and grazing lands. Fig. 3 - A woman carrying firewood in North East India 7
3.5 Hydro-Power Water-energy is most conventional renewable source of energy. Energy is obtained from water flow, water falling from a height. Hilly and highland areas are suitable for this purpose, where there is continuous flow of water in large amounts falling from high slopes. Dams are constructed over rivers. Rain water or river water stored in dams is made to fall from heights. The falling water flows through pipes inside the dam over turbine blades placed at the bottom of the dam. The moving blades then turn the generator to produce electricity. This is called hydro electricity. The water discharged after the generation of electricity is used for irrigation.
Fig. 4 - Hydroelectric Power Hydro-power is a clean, non-polluting source of energy. It can be transmitted to long distance through wires and cables. But, this form of energy can not be stored for future. Thus markets are to be fixed before generation of this form of energy. One fourth of the world’s electricity is produced by hydro-power. Norway, Switzerland, Canada, Sweden and New Zealand harnessed their water resources for water energy. In South America, about 75 % of the total electricity consumption comes from water. Japan, USA and former USSR are the leading countries in production of hydro-power. In India the generation of hydro-electric power was emphasized from the First Five Year Plan when a number of multipurpose river valley projects such as Bhakra Nangal project on river Sutlej, Bokaro in Panchet and Talaiya in Damodar Valley and Hirakund, Rihand, Nagarjuna Sagar, Kosi, koyana were launched to generate hydroelectric power, apart from their use for irrigation and other purposes. A number of such projects including construction of large dams as Tehri Dam on Bhagirathi river in Uttarakhand, Sardar Sarovar in Gujarat, and Narmada Valley Project (NVP) are also under different stages of development. India has immense amount of hydro-electric potential estimated at 84,000 MW. It ranks fifth in terms of exploitable hydropotential on global scenario. 8
Hydroelectricity produces no primary waste or pollution. But, construction of dams leads to several environmental problems, such as submergence of plant and animal habitats and displacement of local inhabitants including tribals. 3.6 Nuclear (Nuke) Energy Nuclear energy can be generated by nuclear fission in which nucleus of certain isotopes with large mass number is splitted in to lighter nuclei on bombardment of neutrons in order to release a huge amount of energy through a chain reaction or by nuclear fusion in which two isotopes of light elements are forced to form a heavier nucleus releasing enormous energy in the process. The heat energy produced as a result of either of the process is used to produce steam which runs electric turbine and generates electricity (Fig. ). The process of nuclear fusion is difficult to initiate but releases more energy then nuclear fission.
Fig. 5 - Nuclear power reactor generating electricity Nuclear energy has a tremendous potential but any leakage from the nuclear reactor may cause devastating nuclear pollution including world’s most hazardous Chernobyl disaster. Disposal of nuclear waste is also a troublesome process. Uranium, a rare element, is the primary source of nuclear energy although thorium can also be converted into uranium isotopes and used as a fuel. Today nuclear energy accounts for about 6 percent of total commercial energy. There are over 300 atomic power plants, operating in the world. The maximum are in USA (83), followed by USSR (40), UK (35), France (34), Japan (25), F.R. Germany (15) and Canada (13). In India first nuclear power station was raised at Tarapore, near Mumbai in 1969. The nuclear power is still not well developed as there are only five nuclear plants, namely, Narora (UP), Rawatbhata (Rajasthan), Kakrapur, Tarapur (Maharashtra) and Kalpakkam (TamilNadu). At present country produces 2250 MW (2.6 % of the country’s total installed power generation capacity) from these nuclear power generation plants. By 2050, it is expected to rise to 25 percent. In India uranium deposits are found in Gaya and Singhbhum districts of Bihar, Udaipur and Jaipur district of Rajasthan, Nellore district of Andhra Pradesh, and Palghat district of Kerla. Reserves of thorium are found in Rajasthan and Andhra Pradesh and coastal parts of India. 9
4. Non-Conventional Sources of Energy The increasing use of fossil fuels is leading to its shortage. It is estimated that if the present rate of consumption continues, the reserves of these fuel will get exhausted. Moreover, their use also causes environmental pollution. Therefore, there is need for using nonconventional sources such as solar, wind, tides, geothermal heat, and biomass including farm and animal waste as well as human excreta. All these sources are renewable or inexhaustible and do not cause environmental pollution. More over, they do not require heavy expenditure. They are capable of solving the twin problems of energy supply in decentralized manner and helping in sustaining cleaner environment. 4.1 Solar Energy Sun is the source of all energy on the earth. It is most abundant, inexhaustible and universal source of energy. All other sources of energy draw their strength from the sun. Solar energy can be used directly or indirectly for human welfare. The direct solar energy is the radiant energy, whereas the indirect solar energy obtained from the materials such as biomass, in which sun’s radient energy has been incorporated by the plants. On global scale, 15 days of solar energy is roughly equivalent to the energy stored in all known reserves of fossil fuels on the earth. The continuous input of the energy from the sun is 1,67,000 times greater than the current consumption. As such, now many countries are in effort to harness the solar energy for domestic, commercial or industrial purposes. Solar energy can be used for direct heating. Alternatively, the heat can be converted into the electricity- the thermal electric generation. Photovoltaic cells-the solar cells or solar batteries convert direct solar energy into electricity.
Fig. 6 - Solar energy India is blessed with plenty of solar energy because most parts of the country receive bright sunshine throughout the year except a brief monsoon period. India has developed technology to use solar energy for cooking, water heating, water dissimilation, space heating, crop drying etc. The grid-connected capacity in the country now stands at 481.48 MW, while the total solar energy potential has been estimated at 50,000 MW.
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4.2 Wind Energy Wind power is harnessed by setting up a windmill which is used for pumping water, grinding grain and generating electricity. Harvesting wind energy is possible only in the areas that receive fairly continuous wind such as islands, costal areas and mountain passes. Areas with constantly high speed preferably above 20 km per hour are well-suited for harnessing wind energy. When gigantic fans, raised on tall towers, are rotated by the wind, rotate wind turbines. These turbines cause the rotation of magnets, which creates electricity. Wind power is a renewable energy source, which has no waste by products, and causes no pollution. But it is quite ‘unpredictable’. When wind speed is low, less electricity is generated. Fig. 7 - Wind energy The gross wind power potential of India is estimated to be about 20,000 MW. India occupies the fifth position, after Germany, USA, Denmark and Spain, in wind power generation adding 2483 MW to the power sector. Gujarat is the first state in the country to start using wind power. Wind mills are used in Rajasthan to draw subsoil water for irrigation. Recently two wind farms of 10 MW each have been established in Tamil Nadu and Gujarat with international cooperation from Denmark. 4.3 Ocean Energy The ocean forms a vital source of energy. Ocean energy is obtained in various forms such as ocean tidal and wave energy, ocean thermal energy conversion etc. a) Tidal energy: Sea water keeps on rising and falling alternatively twice a day under the influence of gravitational pull of moon and sun. This phenomenon is known as tides. Tides are a source of clean and renewable source of energy. But the energy generation may have serious environmental impacts like water salinity and sediment movement. Tidal power or tidal energy is a form of hydropower that converts the energy of tides into electricity. A water turbine is placed in a tidal current, which turns an electrical generator, or a gas compressor that stores the energy until needed. It is estimated that India possesses 8000-9000 MW of tidal energy potential. The most potent sites to produce tidal energy include the Gulf of Cambay (7000 MW approx.) and Gulf of Kuchchh (1200 MW approx.) on the west coast, and the Ganges Delta in the Sunderbans in West Bengal (less than 100 MW). 11
Fig. 8 - Tidal energy b) Ocean Thermal Energy Conversion (OTEC): The sun warms the oceans at the surface and wave motion mixes the warm water downward to depth of about 100 meters and this mix layer is separated from the deep cold water formed at a high latitudes, by a thermocline. This boundary is sometimes marked by an abrupt change in temperature, more often the change being gradual. Thus, the resulting temperature distribution consists of two layers separated by an interface with temperature differences between them ranging from 10 ºC to 30 ºC. The higher values are found in equatorial waters. And these two enormous reservoirs in some oceanic regions provide the heat source and heat sink required to operate the heat engine. The engine using this energy is referred to as OTEC which makes use of the difference in temperature between the two layers of the sea to harness energy which in turn is used to drive turbines for generating electricity.
Fig. 9 - Closed cycle OTEC system 12
The concept of OTEC was first demonstrated in 1979 when a small plant mounted on a barge off Hawai, USA produced 50 KW gross power. India possesses a huge potential of OTEC which could be of the order of about 500,000 MW, about 150 percent of the present total installed power generation capacity of the country. Some of the best global OTEC sites are situated off the Indian mainland and near the islands of Lakshadweep, Andaman and Nicobar. 4.4 Wave energy Wave power systems convert the motion of the wave into usable mechanical energy, which in turn, can be used to generate electricity. These systems can be floating or fixed to the seabed offshore, or may be constructed at edge on a suitable shoreline. The incessant motion of the sea surface in the form of water waves caused by wind constitutes a source of energy. About 1.5 % of the incoming energy from sun is converted to wind energy. Part of this is transferred to the sea surface resulting in the generation of waves. This then is carried to coastal lines where it is dissipated as the waves break. Extract of energy from waves is more efficient than direct collection of power from wind, since the wave energy is concentrated through the interaction of the wind and the free ocean surface. For india whose coastal line extends to about 6000 km in length the annual wave energy potential is estimated to be about 60000 MW approximately (between 5MW to 15 MW per meter). India has initiated the wave energy project near Trivendrum in Kerla as an indigenous effort. It was expected that on the completion, the project would be able to derive an energy output of 4.45 lakh units per year. The project resulted in a strict reality in 1991 when it started generation of electricity to be fed to the grid of Kerla State Electricity Board. It is estimated that wave energy potential along the Indian coast is. 4.5 Geo-Thermal Energy Heat energy obtained from the earth is called geothermal energy. The temperature in the interior of the earth rises steadily as we go deeper. Some times this heat energy may surface itself in the form of hot springs. Geothermal energy in the form of hot springs has been used for cooking, heating and bathing for several years. This heat energy can be used to generate power. The natural heat from the interior of the earth can be converted into energy. This natural heat comes from the fission of radioactive material present in the rocks in the interior of the earth. The idea of harnessing geothermal energy, utilizes dry steam, was developed in Italy as early as in 1904. Natural internal heat of the earth was harnessed by geo-hydro-thermal conversion, hot igneous and geo-pressured systems. Heated groundwater flowing upwards as hot water stream and hot springs- nature’s geysers, can be used to turn turbines and generates electricity.
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Fig. 10 - Geo-thermal energy USA has the world’s largest geothermal power plants followed by New Zealand, Iceland, Philippines and Central America. In India, geothermal plants are located in Manikaran in Himachal Pradesh and Puga Valley in Ladakh. Assessment of geothermal energy potential of selected sites in Jammu and Kashmir, Himanchal Pradesh, Uttarakhand, Jharkhand and Chhattisgarh is being undertaken. Some more field investigations, including deep drilling at potential geothermal sites, would be required before these sites can be taken up for development for geopower generation.
Fig. 11- Geothermal Energy in Manikaran 4.6 Energy from Biomass Biomass generally refers to the organic matter generated by plants through photosynthesis, wherein solar energy combines with CO2 and moisture to form carbohydrates and oxygen. Materials having combustible organic matter are referred to as biomass. Biomass contains C, H and O which are oxygenated hydrocarbons. It generally contains a high level of moisture and volatile matter but has a low bulk density and calorific value. Biomass refers to all 14
plant material and animal excreta when considered as an energy source. Some important kinds of biomass are inferior wood, urban waste, bagasse, farm animal and human waste. Coal is the end product of a sequence of biological and geological processes that biomass undergoes. Biomass energy is the utilization of energy stored in organic matter. It is humanity’s oldest external source of energy, dating back to prehistoric man’s first use of fire. And biomass is still an important part of the world’s energy system; the use of traditional biomass—charcoal, firewood, and animal dung—in developing countries accounts for almost 10% of the world’s primary energy supply. Biomass is an attractive energy source for a number of reasons:
Biomass is a renewable energy source generated through natural processes and as a byproduct of human activity.
It is also more evenly distributed over the earth's surface than fossil fuel energy sources, and may be harnessed using more cost effective technologies. It provides us the opportunity to be more energy self-sufficient and helps to reduce climate change.
It helps farmers, ranchers and foresters better manage waste material, providing rural job opportunities and stimulating new economic opportunities. Bioenergy can be utilized in varied appications:
Biomass can be combusted to produce heat (large plants or localized biomass boilers), electricity, or used in combined heat and power (CHP) plants. Biomass can also be used in combination with fossil fuels (co-firing) to improve efficiency and reduce the build up of combustion residues. Biomass has potential to replace petroleum as a source for transportation fuels.
Biomass is also used in conjunction with fossil fuels for electricity generation in “wasteto-energy” projects. These are niche applications, which depend on the biomass having no other commercial value and being in close proximity to the application. Organic waste such as dead plant and animal material, animal dung and kitchen waste can be converted into a gaseous fuel called biogas. The organic waste is decomposed by bacteria in biogas digesters to emit biogas which is essentially a mixture of methane and carbon dioxide. Biogas is an excellent fuel for cooking and lighting and produces huge amount of organic manure each year. Energy is everywhere but we can see that harnessing this energy is both difficult as well as costly. Each one of us can make a difference by not wasting energy. Energy saved is energy generated. Act now and make brighter energy future. 15
Fig. 12 – Biogas Production Biomass is highly diverse in nature and classified on the basis of site of origin (Table-2), as follows: Table 2 - Sources of biomass Field and plantation biomass Agricultural crop residuesCobs, stalks, Straw, Cane thrashes and etc Edible matters from cropsEnvironmentally spoiled grains, pulses, fruits, nuts, spices, seeds and lint etc Dedicated energy cropsBamboo, Prosopis, Casuarinas, Willow and poplar etc Plantation debris-Leaves, stubbles, barks and trunks etc Livestock wastes from fields, slaughter houses and animal husbandries etc
Industrial biomass Agro-industrial processed biomass and their wastes: Husk Oil cake Sugar bagasses Sugar molasses, Whey Hides and skin wastes Fruit and pulp debris Saw dust Wood pulp and paper shavings Fermented microbial mass etc
Forest biomass Timber
Urban waste biomass Municipal solid wastes
Aquatic biomass Microalgae blooms
Log residues Sewage sludges Forest floor debris Animal carcass
Kitchen and canteen wastes
Sea weeds (E.g. Kelp) Fresh water weeds (E.g. Water Hyacinth) Dead fishes
India is the 7th largest country in the world spanning 328 Million hectares and amply bestowed with renewable sources of energy. It has been estimated that India produces about 450 million tonnes of biomass per year, of which about 200 million tonnes is surplus. Biomass tops the list in providing 32% of all the primary energy use in the country.
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5. Comparison of various Energy Sources A very brief summary of advantages and disadvantages of different types of energy sources are discussed in Table - 2. Table - 2: Advantages and disadvantages of various energy sources S. No.
Energy Source
Type of energy source
Advantages
Disadvantages
Extensively available Efficient Conversion to electricity Easier to transport (tankers) Basis of petrochemical industry Easier to transport (Pipelines) Cleaner than oil and coal Cheaper than oil Easy access Provides energy to a large number of people
1
Coal
Conventional Non-renewable
2
Oil and Natural Gas
Conventional Non-renewable
3
Fire wood
Conventional Non-renewable
4
Hydro-power
Conventional Renewable
5
Nuclear energy
Conventional Non-renewable
Non-polluting Promotes irrigation and fishing Cheap Emits large amount of energy
6
Solar energy
Non-conventional Renewable
Inexhaustible Non-polluting
7
Wind energy
Non-conventional Renewable
Non- polluting Low cost production of electricity once setup Safe and clean
8
Tidal energy
9
Geothermal energy
Non-conventional Renewable Non-conventional Renewable
Non-polluting Inexhaustible Clean eco-friendly always available
10
Bio gas
Non-conventional Renewable
Low cost Easy to operate Make use of bio waste
and
Polluting source Bulky to transport Depletion of oxygen due to oil spillage and gas leakage Pollutants released causes acid rain Exploration of new fuel is not easy Collection is time consuming Polluting Promoting green house effect Deforestation Displacement of local community Inundates low Expensive to setup Generates radioactive waste Expensive Expensive Diffused source, so gets wasted Noise pollution Wind mills costly to setup Disturbs radio and T.V. reception Harmful to birds Destroys wildlife habitat Difficult to harness Located far away from cities and so costly to transport the electricity Causes green house effect
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6. Conclusion Developing renewable energy can help India increase its energy security, reduce adverse impacts on the local environment, lower its carbon intensity, contribute to a more balanced regional development, and realize its aspirations for leadership in high-technology industries. According to a report, India is the third most favoured destination globally, for investments in the renewable energy sector. The report also says that the country will be a major source of new entrants into the sector, after the US and China. The Indian renewable energy market has become increasingly dynamic in recent years as a result of strong natural resources, greater accommodation to international investments and a variety of government incentives. Solar and wind energy will be the major areas to witness overseas investments and acquisitions in the near future. With all the attractive characteristics and potential stated above, India presents a significant market opportunity for renewable energy firms worldwide. However, these firms will need external guidance and assistance on several strategic and operational aspects before they are in a position to effectively tap into this opportunity. -------------------------------------------------------References
NCRET Books. The potential of India’s Renewable energy 2012 report by Gyan Research and Analytics Pvt. Ltd. Energy Resources and India’s Security 2009 Report by Teri , The Energy and Resource Institute. Overview of Renewable Energy Potential of India, 2006, Global Energy Network Institute (GENI). www.geni.org India Ministry of Non-Conventional Energy Sources (MNES) http://mnes.nic.in/ The President of India www.presidentofindia.nic.in The Energy & Resources Institute (TERI) http://www.teriin.org/ Trade Team Canada Environment (TTC Environment) http://strategis.ic.gc.ca/epic/internet/inenva.nsf/en/h_eg02268e.html U.S. Energy Information Administration (EIA), http://mospi.nic.in/mospi_energy_stat.htm Global Energy Network Institute (GENI) www.geni.org Canada India Business, http://canadaindiabusiness.ca/gol/cib/cib.nsf/en/ci00109.html Zenith Energy, http://www.zenithenergy.com/index.HTM Confederation of Indian Industry (CII), http://www.greenbusinesscentre.com/renenegy.asp Centre for Wind Energy Technology www.cwet.tn.nic.in http://www.eai.in
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