Wednesday, September 4, 2019

Potential Of Renewable Energy Sources In Pakistan Environmental Sciences Essay

Potential Of Renewable Energy Sources In Pakistan Environmental Sciences Essay Energy is an essential ingredient of socio economic development and growth. Pakistan, despite of enormous potential of indigenous energy resources, is dependent on external resources for meeting their energy demand. Moreover, Pakistan is among those developing countries with low energy consumption. Only 55% and 20% Pakistans population has access to electricity and natural gas respectively. About 68% Population is living in rural areas and most of them have no access to electricity. At present, the people are facing severe electricity load shedding problems due to shortage of power supply. The country is facing huge economic losses due to the energy crises from the previous two years. Oil (30%) and gas (48.5%) are the major part of the current energy supply. The current oil reservoirs of the country are very low, which fulfill 15% of the oil demand while remaining 85% oil is imported from outside world. The indigenous recoverable reservoirs of oil and gas will exhaust in 13 and 21 y ears respectively. Pakistan has wide spectrum of high potential renewable energy sources, conventional and as well non-conventional, which have not been adequately explored, exploited and developed. The development of the renewable energy sources can play an important role to achieve stable energy supply. This paper discussed potential of different renewable energy resources, which are technically viable in Pakistan. The country can be benefited by harnessing these options of energy generation as substitute energy in areas where sources exist and consequently contributing in poverty alleviation and cleaner environment in Pakistan Key Words: Pakistan, renewable energy, hydropower, wind energy, solar energy, biogas, geothermal, emergy INTRODUCTION Energy is an essential ingredient of socio-economic development and economic growth. Without sufficient energy in useable and at affordable prices, there is a little prospects of developments of improving the economy of a country and the living conditions of people. It is well known fact that technological and industrial advancement is heavily dependent on the readily available energy especially in the form of fossil fuel. The larger proportion of the today energy supplies is still made of fossil fuels. The world is running on 60 % non renewable (Odum and Odum, 2001). It is estimated that global energy demand will be increase by two thirds in 2001-2030 (IEA, 2002a). The reservoirs of fossil fuel are not unlimited and at the present rate of consumption they will not last very long. The world community today uses up in one minute what it took the earth a millennium to create. The oil reservoirs are decreasing and it is predicted that fossil fuels can only meet the worlds energy demand just for three decades more (IEA, 2002a). Moreover, it has been conclusively proved that climate change, which has been resulting in global warming, is mainly caused by greenhouse gas emissions from energy generating systems based on fossil fuels. Yet another aspect that has come into sharp focus is that the developing countries can ill afford to depend excessively upon petroleum imports marked by volatile price fluctuations Since the inception of Pakistan, the primary power supplies from the conventional energy sources were (and are still today) not enough to meet the countrys energy demand. Pakistan, despite the enormous potential of its indigenous energy, remains energy deficient and has to rely heavily on the imports of the petroleum products to satisfy its present day need. Efforts have been made to exploit the existing conventional energy resources to build a strong indigenous exploration and production base. In spite of all these efforts, Pakistan is not able to fully exploit its indigenous energy resources due to variety of reasons. Although, the thermal power generating capacity has increased rapidly during the last few years due to foreign investment, but at same time, it has caused increased air pollution and CHG emission with the result of degradation of health and ecosystem (Ziagham Nayyer, 2005). After the 1970s oil crises, the issues of security of energy supplies and sustainable use of energy sources have become very important policy issues. From then, there has been an increasing interest all over the world for alternative of conventional energy sources to ensure eco friendly sustainable development on the one hand and energy security on the other. This paper describe the potential of renewable energy sources in Pakistan WHY RENEWABLE ENERGY? After the oil crises of the 1970s, all the developed and non oil producing countries were faced with immense oil supply problems. There developed a wide spread economic recession all over the world due to the high oil prices. Moreover, with in rising green movement, the environmental problem became dominant in policy agenda The fossil fuel still continues to dominate the world energy supply. The fossil fuel consumption is more than the earth capacity to generate it. As a result, oil reservoir are draining out very fast and it is predicted that the remaining fossil fuels can only meet the worlds energy demand just three decades more (IEA, 2002a). Moreover, the environmental damage that is created by fossil fuels is also another crucial danger in the future. Along with environmental problems, climate change also created economic and social losses. If the current pace continues, the weather and climate losses will reach almost $ 150 billion by next decade (IEA, 2002a). Because of these reasons, Renewable energy has gained importune in the energy policy agenda Two important global environment initiatives have also stimulated greater interest in renewable in the world. The first was the United Nations Conference on Environment and Development (UNCED) held in Rio de Janeiro, Brazil in 1992. Renewables featured in both Agenda 21 and the Climate Change Convention (United Nations, 1992). Because of the important role of fossil fuels in the build-up of greenhouse gases in the atmosphere (it is estimated that the energy sector accounts for about half the global emissions of green-house gases) and concomitant climate change concerns, renewable are perceived to constitute an important option for mitigating and abating the emissions of greenhouse gases (Socolow, 1992). Renewable also featured high on the agenda of the Johannesburg World Summit on Sustainable Development (WSSD) in 2002. One of the targets proposed at WSSD was for every country to commit itself to meeting 10% of its national energy supply from renewable. Although the 10% target was not agreed to at the summit, there was general consensus that countries should commit themselves to promotion of renewable (WEHAB Working Group, 2002). The main advantage of renewable sources is that they are found in every part of the world depending on geographical and geological situations. In other words, they are indigenous energy sources. The countries does not need to import them, which means they can relieve the dependency problem on one hand and can save precious foreign exchange reserves on the other. Renewable energy has also economic and social benefits; such as jobs creation. In 2002, more than 14 millions jobs have created world wide in RE activities (IEA, 2002a). According to U.S. Department of energy, only in 2002, 25,000 new jobs were created in photovoltaic (PV) industry (Aitken, 2004). RENEWABLE ENERGY RESOURCES IN PAKISTAN Pakistan has wide spectrum of high potential of renewable energy sources, conventional and non-conventional as well, which have not been adequately explored, exploited or developed. As a result, the primary energy supplies today are not enough to meet even the present demand. Moreover, a very large part of the rural areas does not have the electrification facilities because they are either too remote and/or too expensive to connect to the national grid. So, Pakistan, like other developing countries of the region, is facing a serious challenge of energy deficit. Only 55% and 20% of Pakistans population has access to electricity and natural gas respectively. Moreover, about 80% countrys population lives in rural areas and most of them have no access of to electricity. In Pakistan, per capita primary energy supply is only 0.33 million tons oil equivalent (MTOE) while per capita electricity supply is about 520 kWh compared to Worlds average 2,500 kWh At present people are facing severe l oad shedding (about 10 hours a day) due to shortage of 3 GW power supply. Pakistan has very low indigenous fossil fuel resource base and with present rate of production, the indigenous recoverable reserves of oil and gas will exhausted in 14 and 21 respectively. Though there is enormous coal reservoir (185 billion tons) in the country but has not utilized so far due to variety of reasons. The prospect of nuclear energy is bright in Pakistan but high cost, technology barriers and international embargoes are the big hurdles in its course. This shows that conventional non renewable resources are grossly inadequate for meeting the future energy needs of the country. Therefore, development of the renewable energy sources can play an important role in meeting this challenge (Harijan et al., 2008). Pakistan stretches from 24 °N to 37 °N latitudes and from 61 °E to 76 °E longitudes. The total land area of Pakistan is about 800,000 km ². The landscape varies from lofty Karakoram and Himalaya mountains, with the K-2 peak (second highest in the world: 8,613 meters) to the famous desert of Thar and includes fertile plains of the river Indus and its tributaries. The offshore covers over 231,674 km ² in the Arabian Sea. In Pakistan, cropped and forest lands cover an area of about 23 million hectares and 4 million hectares respectively (AEDB website: www.aedb.org) There are quite a number of renewable energy sources, but the resources that are technologically viable and have bright prospects to be exploited commercially in Pakistan include, Solar (PV, thermal), Water (mega local macro-micro-hydel) Wind. Wastes (City solid waste, animal waste) geothermal. Pakistan can get benefit and use these as substitute energy in areas where sources exist. Water Energy Potential Hydropower is one of the oldest forms of energy mankind has used on a mass scale. Mechanical use of hydropower began thousands of years ago by the Egyptians and Greeks for irrigation and milling of grain. Its use for production of electricity dates back to the 19th century in 1882 electricity was produced for the first time by the use of hydropower (Asif, 2008). It is the most versatile source of energy being used in the world. It is renewable, abundant, environmentally friendly and technically mature. It is also regarded as the most economical form of energy. Hydropower is regarded as one of the most important sources of energy Pakistan can count on. Despite the presence of a strong base for Table-1: Proposed sites and their discharge, fall and power potential S# Name of Channel Location Discharge in fee/second Fall in Feet Power Potential in MW 1 Baloki-Sulamanki Link-1 RD106250 12500 10.64 10.00 2 Baloki-Sulamanki Link-2 RD33430 9000 17.86 10.72 3 Chanab-Jhelum Link (Tail) RD316622 13527 41.70 40.00 4 Upper Chanab RD0 16500 8.83 9.70 5 TP Link Canal (DG Khan) RD183000 12000 3.00 12.28 (Source: Hassan, 2002) this form of energy, not enough has been done to tap the precious resource. The hydro potential was estimated at about 50,000 MW out of which about 4,800 MW has been developed over the past 50 years through mega-hydel plants and the remaining has yet to be exploited (Kazi, 1999). The northern areas of the country are rich with hydropower resources. Hydrological survey also revealed that there is a great potential for 300 MW power generations through construction of micro hydropower plants in northern areas of Pakistan (Hassan, 2002). Besides, there is an immense potential for exploiting water falls in the canal network particularly in Punjab, where low head high discharge exists on many canals. Irrigation system of Pakistan is one the largest in the world having extensive network of canal of 160,000 km length. The canal system has a huge hydropower potential at numerous sites/locations on these irrigation canals, ranging from 1MW to more than 10MW, which can be utilized for developi ng small hydro-power stations (Hussan, 2002) Wind Energy Harnessing wind power to produce electricity on a commercial scale has become the fastest growing energy technology. Economic, political and technological forces are now emerging to make wind power a viable source of energy. Data shows that worldwide installed wind power capacity during the period 1996-2008. The total wind power capacity was only 6,100 MW which has increased tremendously and reached to 120791 MW in 2008. Pakistan has a considerable potential of wind energy in the coastal belt of Sindh, Baluchistan and as well as in the desert areas of Punjab and Sindh. This renewable source of energy has however, not so far been utilized significantly. The coastal belt of Pakistan is blessed with a God gifted wind corridor that is 60 km wide (Gharo ~ Kati Bandar) and 180 km long .This corridor has the exploitable potential of 50,000 MW of electricity generation through wind energy (AEDB website: www.aedb.org) Fig.1. Worldwide installed wind power capacity 1996-2008 (Source: http://www.ewea.org/) Fig. 2. Pakistan Meteorological Departments wind mapping stations Source: www.aedb.org Pakistan is a late starter in this field. It is estimated that more than 5000 villages can be electrified through wind energy in Sindh, Balochistan and Northern areas Country first ever commercial 50 MW wind farm has been inaugurated in April 2009 with cooperation of Zorlu Enerji Group of Turkey at Jhimpir, District Thatta, Sindh. Moreover, Projects for generation of 1200MW of electricity from wind are in different stages of development (AEDB website: www.aedb.org) Solar Energy Direct solar energy can broadly be categorized into solar photovoltaic (PV) technologies, which convert the suns energy into electrical energy; and solar thermal technologies, which use the suns energy directly for heating, cooking and drying (Karekezi and Ranja, 1997). Solar energy has for a long time been used for drying animal skins and clothes, preserving meat, drying crops and evaporating seawater to extract salt. Substantial research has been done over the years on exploiting the huge solar energy resource. Today, solar energy is utilized at various levels. On a small scale, it is used at the household level for lighting, cooking, water heaters and solar architecture houses; medium scale appliances include water heating in hotels and irrigation. At the community level, solar energy is used for vaccine refrigeration, water pumping, purification and rural electrification. On the industrial scale, solar energy is used for pre-heating boiler water for industrial use and power gener ation, detoxification, municipal water heating, telecommunications, and, more recently, transportation (solar cars) (Karekezi and Ranja, 1997; Ecosystems, 2002). Solar energy has excellent potential in areas of Pakistan that receive high levels of solar radiation throughout the year. Every day, country receives an average of about 19 Mega Joules per square meter of solar energy (AEDB website: www.aedb.org). During last twenty years Pakistan has shown quite encouraging developments in photovoltaic (PV). Currently, solar technology is being used in Pakistan for rural telephone exchanges, repeater stations, highway emergency telephones, cathodic protection, refrigeration for vaccine and medicines in the hospitals etc. The Public Health Department has installed many solar water pumps for drinking purposes in different parts of the country. Both the private and public sectors are playing their roles in the Popularization and up grading of photovoltaic activities in the country. A number of companies are not only involved in trading photovoltaic products and appliances but also manufacturing different components of PV systems. They are selling PV modules, batteries, regulators, invertors, as well as Source: www.aedb.org Fig. 3. Annual average mean daily Solar Radiation in Pakistan KWH/sq.m practical low power gadgets for load shedding such as photovoltaic lamps, battery chargers, garden lights System (SHS) project in 2005 and basic facilities of lighting, cooking and water disinfection were provided to 11 villages in remote areas of Pakistan. Based on success of this program, the government had approved replication of this project in 400 villages in Baluchistan Sindh (Source: www.aedb.org Energy from Waste For more than twenty years, Waste to Energy has been recognized as a clean, reliable, renewable source of energy. In America today 2,500 MW are solely generated by the waste-to-energy plants. Many other countries including Sweden and Japan have applied this technology since the last 20 years. In the subcontinent, India installed three projects to produce electricity from waste with a total capacity of 17.6 MW ( Shahid 2009) It is estimated that the urban areas of Pakistan generate over 55,000 tones of solid wastes daily ( Ziagham Nayyer, 2005) Unfortunately in Pakistan this source of energy has not been utilized for power generation in the past. The growing urbanization and changes in the pattern of life has given rise to generation of increasing quantities of wastes and its now becoming another threat to our environment. Energy generation from the Animal Waste Pakistan is an agricultural country. About 70% of the population resides in rural areas who meet 95% of their domestic fuel needs by burning bio-fuels Biogas is a potential renewable energy source in Pakistan. An estimate indicates that Pakistan has potential of generating 8.58 ÃÆ'- 1010 cubic meter of biogas 1287 million tones of cattle dung annually produced. The heat value of this gas amounts to 1.8ÃÆ'-112 MJ. In addition, 350 millions tons of manure would also produce with biogas (Illyas, 2006). More than 0.024 millions domestic biogas plans have been installed in Pakistan. These plants are of small size (1-10 m ) capacity and mainly used for cooking and other domestic applications. AEDB has facilitated the Landhi Cattle Colony Biogas project, which upon its completion will be one of the largest wastes to energy projects in the world, generating up to 50 MW of electricity. The pilot phase of 250 kW has been successfully initiated. This project is being implemented by Empower Company of New Zealand and will utilize waste of 400,000 cattle in the area to produce electricity (Source: www.aedb.org) Geothermal Geothermal energy is the energy derived from the heat of the earths core. It is clean, abundant and reliable. If properly developed, it can offer a renewable and sustainable energy source. At an international level, approximately 8,100 MW of geothermal power is generated, out of a global potential of 60,000MW (Marietta, 2002; Bronicki, 2001). Most of the high enthalpy geothermal resources of the world are within seismic belts associated with zones of crustal weakness such as plate margins and centers or volcanic activity. A global seismic belt passes through Pakistan and the country has a long geological history of geotectonic events: Permo-carboniferous volcanism (Panjal traps in Kashmir) as a result of rifting of Iran-Afghanistan micropiates, Late Jurassic to Early Cretaceous rifting of the Indo-Pakistan Plate, widespread volcanism during Late Cretaceous (Deccan traps) attributed to the appearance of a hot spot in the region, emergence of a chain of volcanic islands along the margins of the Indo-Pakistan Plate, collision of India and Asia (Cretaceous-Paleocene) and the consequent Himalayan upheaval, and Neogene-Quaternary volcanism in the Chagai District (Kazmi Jan, 1999; Raza Bander, 1995). This Geotectonic framework indicates that Pakistan should not be lacking in commercially exploitable sources of geothermal energy. Potential geothermal energy sites are identified at Sehwan in Sindh and Koh-e-Sultan in Baluchistan province Fig 4. Geothermal Springs of Pakistan Source: www.aedb.org Emergy, Net energy evaluations and environmental loading of Renewable Energy Sources There is a great potential of renewable energy sources in Pakistan. However, there are some key questions to be address before exploiting these resources. What will be the net energy and emergy from these energy systems? What will be new environmental load they create? Are these energy systems sustainable or not? Explaining these questions is beyond the scope of this paper but I will present a general view of above mentioned concepts. Net Energy Analysis Net energy refers to the ratio of the amount of energy produced to the amount of energy expended to produce it Net energy determines the usefulness of energy system to society. The usefulness of an energy system is determined by a complex combination of physical, technical, economic and social attributes. This includes energy density, power density, emissions, cost and efficiency of conversion, financial risk amenability to storage, risk to human health, and ease of transport. These attributes combine to determine energy quality. Energy returns for investment (EROI) is an important tool uses for net energy analysis. EROI is used to compare the amount of energy delivered to society by a technology to the total energy required to find, extract, process, deliver, and otherwise upgrade that energy to a socially useful form. Hydropower has the highest EROI among the renewable energy resources. Wind energy system has very favorable EROI in the right condition while solar thermal have low E ROI compared to hydropower. They key issue is the size of the surplus that can realistically be delivered by renewable energy system (Cleveland, C.J. 2008) Source: (Odum, H.T. 1998) Fig. 4 Energy transformation, storage, and feedback reinforcement found in units self organized for maximum performance Emergy Synthesis Emergy refers to Available energy of one kind previously required directly and indirectly to make a product or service (Odum, H.T. 1998). Emergy synthesis serves as an alternative method to evaluate the energy flows of a system. It provides a way to account for differences in energy quality, for environmental services provided to a system, as well as a means to measure a systems level of Emergy sustainability. To derive the solar emergy of a resource or commodity, it is necessary to trace back through all the resource and energy flows that are used to produce it and express these input flows in the amount of solar energy that went into their production. This has been done for a wide variety of resources and commodities as well as for the renewable energies driving the biogeochemical process of the earth (Brown, M.T. and Ulgiate, S. 2002) Emergy and energy accounting require systems diagrams to organize evaluations and account for all inputs to, and outflows from, processes. The structures and storages that operate our world of humanity and environment are sustained against the depreciation of the second law by productive inputs for replacement and maintenance. Maximizing the products and services for growth and support appears to be a design principle of self organization as given by Alfred Lotka as the maximum power principle. Pathways in Figure 4 illustrate the flows and conservation of energy. The storage is represented with a tank symbol. The heat sink symbol represents the dispersal of available energy from processes and storages according to the second law. The feedback from right to left interacts as a multiplier increasing energy intake. This autocatalytic loop is one of the designs that prevail because they reinforce power intake and efficient use (Odum, H.T. 1998) Source: (Brown, M.T. and Ulgiate, S. 2002) Fig 5 Aggregated energy systems diagram of an electric power plant, with main inputs and outputs shown and used to calculate performance emergy based indicators. Legends: R1=renewable inputs directly falling on the plant site (sun, wind, rain); R2=renewable inputs supplied by the local ecosystem and used by the plant in the production of electricity (cooling water and air, oxygen for combustion); R=locally renewable input to the process=max(R1; R2) as these inputs are driven by the same (solar) source; N=nonrenewable inputs (such as coal, oil, nd natural gas or groundwater that is used faster than it is recharged); F=goods and services from the economy (F) that are used to construct, operate, and maintain the power plant (construction materials, machinery, general supplies, human services, etc.); Y=Output of a process. Here, the electricity yielded by the plant. By definition, the output is assigned an emergy Y=R+N+F; =chemicals released by the power plant to the atmosphere (from combustion); H = Heat released by the power plant to the atmosphere and the cooling water Brown, M.T. and Ulgiate, S. (2002) evaluated six electricity production systems by using energy and emergy accounting system, in order to rank their relative thermodynamics and environmental efficiencies. They explored out/input energy ratio, emergy yield ratio (EYR) and environmental load ratio (ELR). Generation of CO2  has also been accounted for in order to compare renewable and nonrenewable energy sources Emergy yield ratio, EYR=Y/F=(F+R+N)/F Environmental loading ratio, ELR= (F+N)/R Emergy index of sustainability, IS = EYR/ELR The emergy yield ratio (EYR) provides insight into the net benefit of the various production processes to society. In fact, the higher the fraction of locally available energy sources (R+N) that are exploited by means of the investment  F  from outside, the higher the value of this indicator. Environmental loading ratio expresses the use of environmental service by the system. Environmental service is measured as the emergy of that portion  R  of the environment that is used. When EYR is high due to a high value of local renewable resources, then ELR is small, thus indicating a small environmental stress. On the contrary, when a high value of local nonrenewable sources contributes to EYR, then ELR increases, thus suggesting a larger environmental stress. Therefore, a simultaneous increase of both EYR and ELR, indicates that a larger stress is being placed on the environment; on the contrary, when EYR increases and ELR decreases, the process is less of a load on the surroundin g environment. Brown, M.T. and Ulgiate, S. (2002) concluded that wind generation and hydroelectric power plants have the highest EYR, while the oil fired power plant was the lowest. They also found that electricity generated using wind, geothermal, and hydro power plants had the lowest environmental impact, while fossil fired plants the highest. Further more they also found that the wind and hydroelectric plants had the highest-over-all aggregated (economic and ecological) sustainability, followed by geothermal electricity. CONCLUSION: Pakistan is facing severe energy crises. It is projected that energy demand-indigenous supply gap is increases from 27% in 2005 to 57% in 2030. It is planned that demand indigenous supply gape would be bridge by imported oil and gas. Consequently, import of energy would increase the energy import bill as well as energy security issues. The consumption of fuel will also degrade the environment. Renewable resources in the form of hydropower, wind. Solar PV, Biogas, geothermal etc. are suitable renewable technologies for Pakistan There is substantial potential of these Renewable Energy resources and should be developed for managing the current energy crises and meeting the future energy demand for Pakistan. However there is need of a thorough analysis of net energy and emergy gains from using renewable energy sources. There is also need of investigating the new environmental these alternative sources will create. They key issue is the size of the surplus that can realistically be deliv ered by renewable energy system

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