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Here is a compilation of essays on ‘Climate Change’ for class 8, 9, 10, 11 and 12. Find paragraphs, long and short essays on ‘Climate Change’ especially written for school and college students.
Essay on Climate Change
Essay Contents:
- Essay on the Introduction to Climate Change
- Essay on the Indicators of Climate Change
- Essay on the Scenario of Climate Change
- Essay on the Impacts of Climate Change
- Essay on the National Policy for Climate Change Mitigation
- Essay on the Remarks on Climate Change
Essay # 1. Introduction to Climate Change:
‘Climate change’ is considered as a major critical issue facing the planet Earth. The causes and effects of climate changes have now been fairly well established; the group of gases viz., carbon dioxide/methane and nitrous oxides besides others has become infamous as ‘Green House Gases’ (GHG) leading to global warming and change in climatic conditions. Obviously, the global warming potential of each of these GHG’s varies, as does their lifespan in the upper atmosphere.
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Of all the GHG’s, carbon remains the major target, released due to human activities, largely through thermal power generation and automobile fuel emissions, besides massive rate of deforestation, carbon has been accumulating since the days of industrial revolution, even after the major part of carbon emission being absorbed by green plants and the deep sea.
Climate Change and Global Warming can largely be attributed to the human activities are now well established (IPCC, 2007). The question that was raised in Kyoto, Japan in 1997 about sharing the responsibility of reducing emission still remains unresolved in 2010.
Essay # 2. Indicators of Climate Change:
There are numerous indications that our planet is getting warmer. Although, many scientists still believe that there is not enough proof to prove it. Kyoto Protocol is an important international agreement to curb the emission of greenhouse gases, but many countries, including USA, have not yet ratified it. Many recent studies reveal that this protocol needs immediate attention for human survival.
Many scientists blame natural variability as a likely cause of temperature increase, but the current rise in temperature tracks increased levels of carbon dioxide emissions over the past 50 years. From 1950 to 2002, atmospheric concentrations of carbon dioxide have increased from 311.26 parts per million to 370.89 parts per million. The average temperature over same time rose from 13.83°C to 14.53°C. If carbon dioxide levels continue to rise as predicted, the earth’s average temperature will raise by 1.4 to 5.8°C during this century.
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The Kyoto Protocol under the United Nations Framework Convention on Climate Change sets reduction targets for a basket of six greenhouse gases linked to global warming, the most abundant being carbon dioxide. The Kyoto Protocol becomes law when a minimum of 55 countries covering at least 55 percent of 1990 greenhouse gas emissions have ratified. Recently, Canada and New Zealand governments voted to ratify the Kyoto Protocol, which brings a total of 98 countries, covering 40.7 percent of greenhouse emissions.
2002—Second Warmest Year:
Several new studies have been published that are poignant reminder of why we have to start tackling this problem without any further delay. First, recent data released from National Aeronautics and Space Administration (NASA) indicate that the year 2002 goes down in the record books as the second warmest year on record, since record keeping of global temperatures began in 1867.
Temperatures for the first 11 months of 2002 averaged 14.65°C, which is slightly less than 1998’s record high of 14.69°C. The 15 warmest years since record keeping began have come since 1980 and the three warmest years have come in last five years.
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Each month since November 2001 has been at least half a degree Celsius warmer than average and the January 2002 temperature was highest on record for January. March 2002 was also the highest on record, and in seven out of the eight following months, the temperature was either the second or third highest on record.
The Great Meltdown:
Several studies indicate that human induced global warming has already started affecting the glaciers and icebergs. In 2002 more ice melted from the surface of Greenland than any other year on record. Ice in mountain ranges across the world is also melting at an increasing rate, with possible negative ramifications for water flows in major river systems. Mt. Kilimanjaro has lost 80 percent of its snow ice cover since 1900.
Scientists of the National Aeronautics and Space Administration warn that if current melting rate of glaciers in Arctic region continues, there may be no sea ice left in the region by the year 2099. The NASA study concludes that sea ice is now melting nine percent faster than prior assessment, due to rising temperatures and interactions between ice, ocean and the atmosphere.
Comparing the differences between Arctic sea ice data from 1979 to 1989 and data from 1990 to 2000, the team found the biggest melting occurred in the Western area of Arctic. Previous studies have shown that sea ice in the Arctic Circle is melting at a rate of 37,000 sq. km. year, but the new study suggests the current melt rate may be even faster.
An iceberg named C-19, had broken away from Antarctica and was floating next to Ross Ice Shelf. It measured 124 miles long and 19.5 miles wide, or 2,428 square miles. The report of C-19 came less than a week after C-18 broke free in the same area; it was 47 miles long and 4.6 miles across.
In March 2002 another giant berg broke free in adjacent area, named B-22, it measured 2,120 square miles. Also in March 2002, the 1,250 square miles section of the Larsen Ice Shelf splintered into a plume of drifting icebergs during a five-week period that ended March 7, 2002.
The rate of decline of icebergs is expected to accelerate due to interactions between the ice, oceans and the atmosphere. As temperatures in the Polar Regions rise, the summer ice covers retreat, more solar heat gets absorbed by the ocean, and more ice gets melted by a warmer upper water layer.
Warmer water may delay freezing, leading to a thinner ice cover in the winter and spring, which makes the sea ice more vulnerable to melting in the summer. The study found that temperatures in the Arctic are increasing at the rate of 1.2°C per decade. This rise in summer ice temperatures could lengthen the summers, allowing earlier spring thaws and later freeze dates in the autumn, causing further thinning and retreat of perennial ice.
Snow Accumulation:
Another study by a Canadian-Swiss research team concludes that Western Canada is much affected by global warming and as a result snow accumulates even deeper on the ground. Analysis of an ice core drilled from Canada’s highest mountain indicates that western Canada has experienced significant climate change over the past 150 years.
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The team found that the average annual snow accumulation in Mount Logan remained constant between 1700 and 1850 A.D., but then increased from 1850 onwards. The researchers also say the snow accumulation was greatest in past 10 years. Dr. Kent Moore, leader of the team tells that, “This seemingly paradoxical effect is due to the fact that warmer air holds more moisture that in winter can be released as snow.”
Loss of Biodiversity:
Several new studies also reveal what global warming will mean to our forests and biodiversity. Trees absorb carbon from the atmosphere and store it as wood. For this reason, forests have been dubbed carbon sinks. A new four-year study by 50 international scientists led by Natural Resources Canada shows that pollutants released by power plants and vehicles don’t just cause climate change—they also stunt tree growth.
Higher summer temperatures in the northern hemisphere, as well as lower rainfall, caused the 2002 world grain harvest to fall to 1,813 million tonnes, some 80 tonnes below world consumption. According to Lester Brown, president of the Earth’s Policy Institute, a Washington DC think tank, “the scientific rule of thumb is that a degree Celsius rise in temperature above the optimum reduces grain yields by 10 percent.”
Previous estimates of the amount of carbon stored by trees and shrubs may have been too high, suggests a new study published in prestigious Journal ‘Nature’ few months ago.
The study by researchers from four universities explored whether the trees and shrubs now encroaching on former grasslands are helping to mop up some of the carbon dioxide emitted by vehicles, power plants and other sources. The team concluded that in many locations, the trees may be absorbing less carbon than what is emitted by soil once covered with grasses.
Malnutrition:
A new study warns that nutritional quality of some crops will decrease under the influence of more carbon dioxide concentration in environment. Under high CO2 concentrations the plants produce more seeds with less nitrogen content. Nitrogen is a critical component for building proteins in plants, humans and animals. Many scientists believe that under the rising CO2 scenario, livestock and humans would have to increase intake of plants to compensate for the loss of nitrogen.
This study has been conducted by a team of experts led by Peter Curtis, Professor of evolution, ecology and organismal biology at Ohio State University. The researchers analysed eight different ways plants respond to higher CO2 levels—number of flowers, number of fruits, fruit weight, number of seeds, total seed weight, individual seed weight, amount of nitrogen in seeds and plants capacity to reproduce. The team found that the plants grown at higher CO2 levels had more flowers, more seeds, greater individual seed weight, greater total seed weight but lower concentration of nitrogen in the seeds.
Individual crops varied in their respond to increased CO2 levels. Rice seemed to be most responsive and its seed production increased by 42 percent. Soybean followed with a 20 percent increase in seed, wheat by 15 percent and corn increased by 5 percent.
Nitrogen level decreased, by an average of 14 percent across all plants except cultivated legumes. Peter Curtis concludes the report as a bad news, because nitrogen is important for building proteins. A growing global population demands more food, but humans would have to eat more of the food to get the same nutritional benefits.
The scientists gathered at past year’s annual meeting of Association for Tropical Biology warned that human activities are changing the global climate, and these changes are having far reaching effects on tropical forests. The Association for Tropical Biology says that tropical forests are undergoing unprecedented changes as 1.2 percent of the remaining forest is removed each year, as atmospheric carbon dioxide which fuels plant growth increases by 0.4 percent each year, and as global climate change begins in earnest.
University of Missouri scientist Deborah Clark told the Association that tropical forests may not be carbon sinks that can be used to absorb carbon dioxide generated by the burning of fossil fuels.
Instead, tropical forest may end up contributing even more carbon dioxide to the atmosphere as temperature rises. Positive feedback between higher temperatures and carbon dioxide production by tropical forests could be catastrophic by resulting in accelerated increase in global carbon dioxide levels.
Species Migration:
As global climate change shifts temperatures across the planet, species may not be able follow fast enough. According to United Nations Environment Programme, they will have to migrate 10 times as fast as they did after the last ice age. Many would not make it. There are several reports suggesting that global warming is driving species like butterflies and birds to expand their territories in Europe. It is just a part of emerging worldwide trend that is seeing animals on the move in response to changing climate.
According to Professor Chris Thomas of the University of Leeds, a quarter of butterfly species had begun to move north in Europe, where once it would have been too cold for them to live. An analysis of the bird habitats over the past 20 years also showed an expansion northwards, with bird species in Britain moving an average of 18.9 km north.
Species that migrate due to warming will move at different rates, breaking up existing communities. At high altitudes, entire forest types are expected to disappear, to be replaced by new ones. During this transition, carbon will be lost to the atmosphere faster than it can be replaced by new growth, accelerating climate change.
Another study carried out by British Antarctic Survey tells that thousands of the world’s most exotic species of sea animals from spiders to giant woodlice face extinction if Antarctic sea temperatures rise as predicted.
The water temperatures around the Antarctic—one of the last outposts of relatively untouched environment in the world—were rising at more than twice the rate of the land temperature, having climbed by one degree in the past 15 years.
It is predicted that there will be rise of 3°C within next 100 years. Surveys have shown that the Antarctic sea dwellers were unable to adapt to such temperature changes so they effectively suffocated due to their inability to move oxygen around their bodies.
At the other end of the earth, shrinking sea ice affects Arctic wildlife like polar bears and seals. Since the sea ice is melting earlier in the spring, polar bears move to land earlier without having developed as much fat reserves to survive the ice-free season.
Recent studies have confirmed the event of human induced global warming, its impact and its possible consequences. We can’t count on any carbon sinks, including forests, to behave consistently when the rest of the world is changing. The only reliable way to slow global warming is by reducing emissions and Kyoto is a good way to start.
Essay # 3. Scenario of Climate Change:
International Scenario:
The UN Framework Convention on Climate Change (UNFCCC, 1992) laid the foundation for an international consensus in 1992 and the Kyoto Protocol laid out the road map in 1997. Countries identified as Historic Emitters’ were grouped together and given the task of reducing CO2 by 5.2 per cent below 1992 level between 2008 and 2012. USA didn’t accept it; countries took long years to ratify the Protocol till 2005.
But the reports at the end of 2009 in Copenhagen meet of Conference of the Parties (CoP15) showed the target of reduction remains unfulfilled promises, though it was legally binding. Collectively, developed countries emitted 17 per cent more carbon when compared to 1990 level.
In the major Economics Forum Declaration at L’ Aquila, Italy in 2009, President of USA stated “climate change is one of the defining challenges….. the scenario is clear and conclusive and impacts can no longer be ignored.”
While admitting, ‘Every nation on this planet is at risk and just as no one nation is responsible for climate change, no one nation can address it alone.’ But major developed countries are responsible for more than 75 per cent of carbon pollution.
The target set at the conference is to reduce carbon emission by 80 per cent by 2050 by the developed countries but global target will be to cut emission by 50 per cent. This is targeted to limit global warming ‘to no more than 2°C’ to comply with the findings of scientists across the world.
Developed countries demand that reductions must be ‘measurable, reportable and verifiable’. The politics of climate change, notwithstanding the continuing crisis of global warming related phenomena created international pressure of the global community to act; the much awaited Copenhagen Meet in December, 2009 belied the hope. “Kyoto Protocol” clearly defining the responsibilities and other issues seems to take a back seat.
National Scenario:
India, along with China, is now recognized as one of the fastest developing economies. India’s economic growth is dependent on carbon based energy sector, amongst others and therefore has to commit to cut CO2 emission by 20-25 per cent.
India has announced National Action Plan on Climate Change (NAPCC) in 2008 with eight mission-based targets:
1. National Solar Mission
2. National Mission on Enhanced Energy Efficiency
3. National Mission on Sustainable Habitat
4. National Water Mission
5. National Mission on Sustaining Himalayan Ecosystem
6. National Mission for Sustainable Agriculture
7. National Mission for a Green India
8. National Mission on Climate Change for Strategic Knowledge.
These eight missions involving both mitigation and adaptation measures remain India’s position. The target of Solar Energy Mission with a goal of 20,000 MW of solar power capacity being installed by 2020 is considered most ambitious. Agriculture and water remain critical issues for India’s billion plus population and deserved separate missions; so is the vital role played by Himalayan ecosystem.
The increase in green cover has been reported by ‘Forest Survey of India’ in its latest report but demand of development especially in the mining and industrial sector including thermal power plant continues to take a heavy toll on India’s forest. So the mission for green cover is a welcome feature.
India’s Energy Efficiency Efforts seem to start working by early 2010. The Bureau of Energy Efficiency had launched ‘Bachat Lamp Yojna’ to replace 400 million incandescent light bulbs with CFL bulbs and prevent 40 million tonnes of carbon from entering the atmosphere annually. Supported by Clean Development Mechanism (CDM) scheme of United Nation, it will entitle Indian to win World’s largest Carbon Credit Project.
The investors in the project can sell the Carbon Reduction Unit (CRU) in the international market where buyers like manufacturers and power producers buy the Units to meet their own GHG emission reduction targets (currently it sells al 10-12 Euros). So the private investors in India offering the CFL at minimum price (15 per cent) can recover the investment by 6th-7th year and continue to earn significant project thereafter.
Essay # 4. Impacts of Climate Change:
Impacts of climate change have been discussed globally over last nearly two decades. Sea level rise, crisis in freshwater resources, uncertain cereal output, increasing vector borne diseases, changing migration pattern and flowering time are but some of the significant impacts predicted. The impacts will also lead to mass migration of human population now named ‘Environmental Refugees’ – a new category not yet included in UN Commission of Human Refugees.
Impacts on Biodiversity:
Response of biodiversity to climate change may be varied. Climate change may seriously affect ecosystem and living organism as can be seen from the history of post climate shift. While some population may flourish, others may face crisis for survival. Some species, scientists believe, will be unable to adjust with the shift in temperature and the changing precipitation rate and face mass extinction.
One such study shows ability of the well-known pest, the pine beetles completing life cycle at an altitude that was previously hostile to these insects. Such extension of vertical distribution range can create new problems in the management of pine forests in the temperate region. On the other side, it is observed while some trees can bloom earlier with warmer temperature but pollinators do not hatch early, thereby causing disruption in the propagation of the species.
Such mismatches can occur between predators and prey, herbivorous insects and host plants and pollinators and flowering plants. Population decline due to changing climate such as decline of Krill population in the Antarctic seas may have significant impact on the food chain, which includes Penguin, Seals, Whales and Albatross.
Scientists have observed northward shift of habitats in a wide variety of species to an average of 16 km per year; these include diverse species of birds, butterflies and alpine herbs in the Palaearctic and Nearitic zone. As many as 677 species recorded a shift to earlier spring cycle due to global warming.
In a recent study ‘Surface Air Temperature Variability’ over India during 1901 – 2007 and its association with ENSO’ conducted recently at Indian Institute for Tropical Meteorology (IITM), Pune, showed that temperature data collected from 388 weather station indicate 0.51°C rise in India during last 100 years but since 1970, minimum temperature rose by 0.20°C per decade faster than maximum temperature 0.17°C.
Rising night temperature may affect rice grain in the field, leading to drop in the yield. At ecosystem level, possible impacts on biodiversity due to climate change has been focused. The relationship between climate change and biodiversity is shown in Figure 1.1.
Polar ecosystem witnessed an increase in temperature 10 times faster than the observed surface mean temperature-Penguin, Polar Bear and other animals adapted to typical polar habitat are apt to suffer.
The possible impact on agro-ecosystem besides the loss of food grain may include phonological changes amongst pest, predator and parasitic species. Soil condition, when becoming drier will not only affect crop but also affect the soil micro-arthropods, changes in flowering time may lead to early harvesting resulting in massive reduction in yield.
Deserts, both hot and cold are projected to be either hotter or drier or both. Organisms at the apex of heat tolerance limit are likely to perish under maximum threshold level. Increased rate of wild fire could change the species composition. Desert flora in the Rann of Kutch is comprised of 700 species of flowering plants with nearly 50 per cent species being endemic; more than 300 species of vertebrates inhabit in the area. More than 4500 species of fauna live in Thar Desert (ZSI, 2002).
Forest ecosystem, with small changes in temperature and precipitation can have adverse impact on forest growth. Many forest dwelling large mammals, half of the large primates and nearly 10 per cent of all tree species are already said to be under risk of extinction. Forest fauna, in many cases, depend on fruits and flowers of specific flora and as such will have consequences on the rate of reproduction and survival. Wildlife species in designated areas also become vulnerable unless they are able to shift at higher altitude.
Mountain ecosystem across the world has specific and typical biota stratify at different altitudinal level. Current researches show retreat and sometimes disappearance of alpine species that become trapped on mountain summit. In Alps, some plant species have been migrating upward by one to four meters per decade and some other plants previously resolved from the top of the mountains have disappeared.
A recent study from Institute of Tropical Meteorology, Pune, India shows that among regions, the hardest hit area is western Himalaya en-comprising portions of Jammu and Kashmir, Himachal Pradesh and Uttarakhand. Here the mean temperature rise in the last century was 0.80°C, but more recently it has become 0.46°C per decade. This rapid warming would not affect glaciers but the unique biota which include more than 3000 flowering plants and 5700 faunal species representing 6.4 per cent of Indian fauna as evidenced from the study conducted at IITM, Pune (unpublished).
Freshwater ecosystem, fed by both melting of ice and annual rainfall, can undergo serious changes in terms of faster melting of glaciers and inadequate formation of ice in succeeding years as also from uncertain rainfall pattern. The warming of rivers, altered mixing regime, altered flow regime and greater frequencies of flood and drought can all affect growth, reproduction and distribution of aquatic biota including food fishes.
Migratory birds dependent on lakes and stream’s water resource and quality are also likely to suffer. It is to be mentioned that freshwater flora in India includes 87 species of pteridophytes and 690 species of angiosperms.
Marine and coastal ecosystem perhaps can be considered most vulnerable with potential sea level rise due to climate change. Coastal flooding, storm surges, cyclones and phenomena like Tsunami, are likely to affect fragile coral reef region and breeding ground of marine fishes.
Changes in the phytoplankton biomass is predicted due to expected increase in atmospheric CO2 which in turn will give rise to a threefold increase in surface water CO2 contamination. These will affect seawater pH and enzymatic activities of phytoplanktons.
Essay # 5. National Policy for Climate Change Mitigation:
Climate change is a problem that is inherently different from other environmental problems with which humanity has grappled, because the assumption that prior experience with other air pollution problems is a good model upon which to base climate policy responses fails at many levels.
Primarily those who are alive in the future will face the consequences of climate change. The present generation has inherited the atmosphere and associated climate from its ancestors. Options to mitigate climate change include actual emission reductions and carbon dioxide sequestration, investments in technology development for economically viable reductions.
The Government of India has been an active participant in the climate change negotiations since the inception of United Nations Framework Convention on Climate Change (UNFCCC) in 1992. India is a party to the UNFCCC and was the 38th country to ratify it on November 1, 1993. The Ministry of Environment and Forests is the nodal ministry for all environment related activities in the country and is the nodal ministry for co-ordination the climate change policy as well.
The working group on the FCCC was constituted for the implementation of obligations under the FCCC and to act as a consultative mechanism in the Government for impacts to policy formulations on climate change. To enlarge the feedback mechanism the Government of India has constituted an Advisory Group on Climate Change under the chairmanship of the Minister of Environment & Forests.
The policy of the Government of India on reduction of Greenhouse gas emissions is based on three broad principles:
i. That the primary responsibility of reducing greenhouse gas emission is that of developed countries, and hence should show a demonstrable sincerity in initiating actions to address climate change;
ii. That the development needs of developing countries are of prime importance; and
iii. That the developed world should transfer resources and technologies at favourable terms to the developing world, thereby, facilitating developing countries to move towards a sustainable development path.
Development of National Guidelines:
The national guidelines or framework for monitoring greenhouse gas emissions and policy options for reducing greenhouse gas should emphasize not only on issues associated with climate change but also include the following:
i. Emission forecasting.
ii. Setting goals.
iii. Policy criteria.
iv. Policy evaluation.
v. Organizational and political issues.
Climate change and greenhouse gas emission and sequestration spun any sectors of society and extend far into the future. Furthermore, policy measures to address greenhouse gases overlap with many other public policy objectives, often in a complimentary way.
Policy formulations can be a complex undertaking that involves understanding the issues, envisioning the range of actions that governments can take to address those issues and selecting from within this range of approaches that offer the most potential for achieving multiple public goals.
The policy formulation process must respond to local circumstances and must fit within institutional, fiscal, political and other constraints. The presence of uncertainties, diverse economic sectors, and long lag times between emissions and effects, as well as the political sensitivity associated with the climate change issues, further complicates actions to reduce greenhouse gas emissions. The Government of India has nevertheless addressed a larger number of local and regional environmental issues in its developmental strategy that are complementary to the climate change issues.
Abatement Technologies:
According to available estimates, as much as 50% of the share in the increase of greenhouse gases is on account of carbon dioxide, while tin- remaining 50% is contributed by methane, nitrous oxide and chlorofluorocarbons. As coal will continue to be a main source of commercial energy in India, there is an urgent need to take measures for reducing the emissions of carbon dioxide, which is predominant greenhouse gas.
This can be achieved through the following measures for which technologies are available:
i. Improvement in combustion efficiency and use of beneficiated coal;
ii. Increase in plant load factor (PLF) and conservation of electricity by reducing transmission and distribution losses;
iii. Energy efficient systems for end use of electricity in various sectors including industry, agriculture and household; and
iv. Non-conventional energy sources.
Coal Beneficiation:
Reduction of carbon dioxide emission will be around 8.4%, if coal ash is reduced from 41 % to 34% in the coal supplied to power plants. Further reduction can be achieved with lower ash content in coal. A net reduction of 10% in carbon dioxide emission is possible through beneficiation of coal through reduction of ash content by 10 units. Alongside, the quantity of suspended particulate matter will be reduced by as much as 28.5% and consumption of energy for transportation will be reduced by 13.8%.
From the view point of pollution control as well as greenhouse gas emissions, the benefits of coal beneficiation can hardly be overemphasized.
The trial using beneficiated coal at the Satpura Power Station showed that various advantages of coal beneficiation include the following:
i. Plant utilization factor increased from 73% to 96%;
ii. Specific coal consumption decreased from 0.777 kg/kwh to 0.533 kg/kwh;
iii. Support fuel oil consumption was totally eliminated;
iv. Specific auxiliary power consumption for the unit was reduced by 1.5%;
v. Downtime of coal mills was reduced significantly;
vi. No wall slogging, boiler tube leakage, clinker formation etc. was reported;
vii. Boiler efficiency improved by 2% with slashed coal; and
viii. Smoke and dust emissions were reduced considerable.
If all power coal transported over 1000 kms is washed, the following savings/benefits in the year 2009-2010 can be achieved:
Increase of Plant Load Factor in Coal Based Thermal Power Plants:
The average Plant Load Factor (PLF) for the thermal power plants in India is around 55%. But, these plants operate with varying efficiency ranging from a meager 10% to as high as 75% PLF.
The reasons attributed to poor efficiency include:
i. Continued operation of plants (more than 20 years old) which have outlived their life;
ii. Erosive characteristics of coal; and
iii. Poor maintenance.
Millions of Rupees have been invested in power plants, however, due 10 their operation with poor plant load factor and high transmission loss, there is chronic shortage of power. Hence, we are required to invest in new facilities for power generation which involve huge expenditure.
A reasonable well maintained system should operate at over 80% PLF for the first 10 years, down to 75% at the end of 20th year and down to 50% at the end of the 30th year. A life extension programme can restore the plant capacity to its original level for another 20 to 30 years. There is no reason why this cannot be achieved in India.
It is estimated that the cost of retrofitting would be not more than Rs. 10 million per MW against the cost of investing in new facilities at Rs. 35 million to Rs. 40 million per MW. With an investment of Rs. 124,000 million to optimize the existing plants, it may be possible in generate as much as 12,000 MW of additional power and concurrently achieve significant reduction of particulate matter and sulphur dioxide emission. On the other hand new facilities for generating 12,000 MW power would cost over Rs. 403,000 million and tin problems of pollution from the existing plants will continue.
Reduction of Transmission and Distribution Loss of Electricity:
The transmission and distribution loss in India is of the order of 23-24%.
It is estimated that one percent of saving in transmission and distribution loss would be equivalent about 380 MW. The technology is known and the investments could be recovered in many cases within a year. The potential for saving of power by bringing down the transmission and distribution loss is around 4,000 MW. This will also lead to reduction of pollution to the tune of 24,000 metric tonnes of dust and 570 metric tonne of sulphur dioxide per day which will be otherwise generated during production of additional 4000 MW of electricity.
Ozone Depleting Substances:
As a short-term measure, one of the available alternatives is to use HCFCs which destroy ozone to a lesser extent. To replace chlorine- containing substances, several substitutes have been developed while research is needed to find other alternatives. As of now, the most viable compound to replace CFC-12 is HCFC-134a. For foam blowing HCFC-22, HCFC-141b and HFC-123 are some of the substitutes.
In fire-fighting sector, there is no substitute for halons. Some of the alternatives are dry chemical powder and carbon dioxide. In aerosol sector, hydrocarbons, dimethyl ether, compressed carbon dioxide, nitrogen and Nitrous oxide can be used as substitutes for propellants. The alternative aerosol system includes finger and trigger pumps, mechanical pressure dispenser etc. The currently available alternatives in sterilization sector are ethylene oxide, carbon dioxide and steam.
Among the HCFC and HFC alternatives, only HCFC-22, HCFX- 142b, HFC-152a and HFC-134a are currently available and can be made available in large quantities at relatively short notice. Halon replacement chemicals are not at the same stage of development as CFC replacements or refrigeration, solvents and other applications.
Essay # 6. Remarks on Climate Change:
The phenomenon of climate change and global warming is happening now at a pace faster than any time in the past. The economic cost of climate change is calculated at 2.5 times more for inaction rather than action, both adaptive and mitigative. Of the impact change, one of the most worrying is on biodiversity. Human societies still depend on biodiversity for its food security, fodder, fuel wood, medicinal, textile, leather and hides, oilseeds, beverages to a variable degree.
Changes in biodiversity are likely to originate largely from changes in land use followed by climate change. Consequences of changing climate and changing biodiversity are being researched but it is believed ‘Human alteration of global environment has triggered the sixth major extinction event in the history of life’. These undoubtedly will have ‘profound consequences for services that human derive from ecosystem’.
While climate change may endanger the lives and livelihood of millions of people across the world, the surviving population will perhaps face the maximum crisis due to disruption of ecosystem services. May be a new international body comparable to IPCC should assess changes in biodiversity and their consequence as an integral component of the assessment of the societal impacts of global change.