Losses In Xlpe Insulated Cables Engineering Essay

Losses In Xlpe Insulated Cables Engineering Essay Power cables, mainly underground power cables form a bulk part of electrical power systems network. Accordingly, when medium voltage XLPE cables were first installed in the late 1960s, cable manufacturers and electric utilities expected them to perform reliably for 20 to 30 years. However, history has shown that these cables had high percentage of life losses whereby the service life of some of these cables was far shorter than expected. Many cables failed after only 10 to 15 years in service. The failure of XLPE cables was happened due to the aging process. Aging of XLPE cables is related to the temperature of the insulation. For XLPE cables, the normal maximum operating temperature is 90  °C. At this maximum value, the consumption rate of anti-oxidant has been calculated to afford a cable life of 30 years. Increasing the XLPE cables operating temperature will increase the rate which the anti-oxidant is used up. Subsequently, it will reduce the service life of XLPE cables. The rea ction follows the Arrhenius relationship which is an exponential function. From this, even a small increase in temperature, it will hence give significant impact on the aging process of XLPE cables. Once the anti-oxidant in the cables is used up, the cables will start to oxidize and become easily broken. Then, the cables will be subject to stress cracking and electrical failure at positions of mechanical stress. In addition, the presence of harmonics in power system causes a conductor to overheat. This overheating process makes the cable to increase in term of temperature to its insulation. Therefore, cable will soften and the mechanical performances will reduce which is called as premature aging. Thus, it is important to investigate the presence of harmonic in any electrical equipment. From this we could know the temperature due to the overheating process and evaluate the life losses of any associated cables. TABLE OF CONTENTS CHAPTER TITLE PAGE DECLARATION 1 ACKNOWLEDGEMENT 2 ABSTRACT 3 TABLE OF CONTENTS 4 1 INTRODUCTION 8 1.1 Background 8 1.2 Premature Aging due to Harmonic 9 1.3 Development of Power Cables 9 1.3.1 Oil-Impregnated Paper Power Cables 10 1.3.2 Solid-Dielectric-Extruded Power Cables 11 1.3.2.1 Technology of XLPE Cables 13 1.4 Losses in Power Cables 15 1.5 Objectives of Study 16 1.6 Scopes of study 17 2 LITERATURE REVIEW 18 2.1. Introduction 18 2.2. Power System Harmonics 18 2.2.1. Definition of Harmonics 19 2.2.2. Source of Harmonics 19 2.2.3. The Harm of Harmonic 20 2.2.4. Effects of Harmonics on Power System 21 2.2.4.1 Motors and Generators 21 2.2.4.2 Transformers 22 2.2.4.3 Power Cables 22 2.2.4.4 Capacitors 23 2.2.5. Economical Damage due to Harmonic Losses 23 2.3 Underground Power Cables 24 2.3.1 Gas-filled Cable 24 2.3.2 XLPE Cables 27 3 EVALUATION OF THE AGING COST DUE TO HARMONIC LOSSES IN XLPE CABLES 29 3.1 Introduction 29 3.1.1 Flowchart 30 3.2 Calculation of Losses 31 3.2.1 Resistance of the conductor 31 3.2.2 Skin Effect 32 3.2.3 Proximity Effect 33 3.2.4 Total Power Losses 33 3.2.4.1 Joule Losses 34 3.2.4.2 Dielectric losses 34 3.3 Probabilistic Evaluation of the Economical Damage due to Harmonic Losses 35 3.3.1 Expected Value of the Aging Cost due to Harmonic Losses 35 3.4 Conclusion 39 4 DATA, MODELLING AND ASSUMPTIONS 40 4.1 Data 40 4.2 Assumptions 41 5 RESULTS, ANALYSIS, AND DISCUSSIONS 42 5.1 Results 42 5.2 Discussions 45 6 CONCLUSIONS AND RECOMMENDATIONS 46 6.1 Expected result 46 6.2 Conclusions 47 6.3 Recommendations 47 REFERENCES 49 APPENDICES APPENDIX A 52 APPENDIX B 58 APPENDIX C 67 APPENDIX D 68 APPENDIX E 69 APPENDIX F 72 APPENDIX G 73 Background By means of the discovery of electricity in the early 19th Century, all countries in the world nowadays have virtually utilized electricity as a source of light and energy. This has led to the existence of distribution-transmission line system carrying current, even if at different voltages and transporting it over long distances till the end users or customers. For the distribution-transmission line system, engineers had thought critically in finding the suitable power cables for power system. Mainly, most of the bulk electrical energy generated from the generation centers is being transported to major load centers within a large geographical area by the transmission systems using overhead lines [1]. In the other words, the distribution system delivers the electrical energy from these load centers to customers who are within a smaller geographical area. For safety, reliability and aesthetics, the electric circuits used to transport energy to such customers are usually underground power cables, though this kind of arrangement is expensive but has more advantages than the overhead lines [2]. Over the years, high demand of reliable electricity power supply has led the electricity markets to be highly competitive. Electric utility companies now have to develop means of maintaining, enhance the safety and reliability of their expensive power system components to operate advantageously and meet the demands of their customers. One of power system component that constitutes a bulk part of the distribution and transmission line systems in urban areas is the underground power cable. For instance, in the United Kingdom there are about 93000 km of 11 kV cable and more than 13000 km of 33 kV [6]. In Malaysia with rush of development has led to increasing demands of electrical energy. Doing this, underground cable distribution is increasing significantly. It is estimated that there are about 180000 km of underground cables in Malaysia, forming about 80 % of the underground power distribution system. This shows that, the technology of underground power cables has grown up very fast by the time as the world is moving extremely in science and technology. However, lately the presence of harmonic in electrical energy systems is well known [3]. The harmonics are due to nonlinear loads such as static converter and can damage the system components [6]. In the case of the cables, harmonics can cause relevant additional losses in the conducting and in the insulating materials which cannot be neglected. From the economical point of view, the presence of harmonics can cause economical damage which increasing the operating costs and decreasing the useful life of the system components. The economical damage due to harmonic losses can be defined as the summation of the operating costs and the aging costs. As stated in [13], the operating costs are referred to the costs of the incremental energy losses caused by the harmonic flow in the component, where the term incremental means that these losses are superimposed to the ones at the fundamental while the aging costs are referred to the incremental investment costs caused by the premature aging of the components caused by the harmonic pollution. Premature Aging due to Harmonic Aging failures have become a major and urgent concern in many utilities since many power system components are approaching the turning point to the end of life. For the case of power cables, the premature aging occurs due to harmonic pollution. The harmonic flow can lead to additional heating in power cables. Subsequently, temperature will rise and premature aging may result. Development of Power Cables [1] Power cable technology had its beginnings in the 1880s when the need for power distribution cables became pressing. With urban growth, it became increasingly necessary to replace some of the overhead lines for power transmission and distribution system with underground cables. The illumination of the larger cities proceeded at such a rapid pace that under some circumstances it was impossible to accommodate the number and size of feeders required for distribution, using the overhead line system approach. In fact this situation deteriorated so notably in New York City that, in addition to the technical and aesthetic considerations, the overhead line system began to pose a safety hazard to the line workers themselves, the firemen, and the public. As a result, the city passed an ordinance law in 1884 requires removing the overhead line structures and replacing them with underground power cables. Similar laws and public pressure were applied in other cities, with the consequence that by the early 1900s, underground electrification via insulated cables was on its way to becoming a well-established practice [14]. A practical lead press was invented in 1879 and subsequently employed to manufacture 2kV cables for Vienna in 1885. During the same period, vulcanized rubber was used to produce cables on a commercial scale, although use of guttapercha had already been made as early as 1846. Impregnated-paper power cables were first put on the market in 1894 by Callender Cables of England, using impregnant mixtures of rosin oil, rosin and castor oil and only in 1918 were these replaced by mineral oils. In North America, impregnated-paper cables were first supplied by the Norwich Wire Company. Varnished cambric cables were introduced by the General Electric Company in 1902. The behavior of these cables with hightemperature was subsequently improved the addition of black asphalt. Some of the more common early solid and liquid insulating employed in various underground cable installations were natural rubber, gutta-percha, oil and wax, rosin and asphalt, jute, hemp, and cotton. In 1890, Ferranti developed the first oil-impregnated-paper power cable. By following their manufacture, his cables were installed in London in 1891 for 10 kV operations. In addition, the cables were made in 20 ft lengths as the total circuit was 30 miles in length about splicing joints were four required. Nevertheless, these cables performed so well that the last cable length was removed from service only in 1933. Cable installation continued to proceed at a rapid pace, so that by the turn of the 20th century many major cities throughout the world had many miles of underground power cables. For example, already by the end of 1909, the Commonwealth Edison Company in Chicago had 400 miles of underground cable operated in the voltage range between 9 to 20 kV. Montreal had some 4500 ft cir cuits of three-conductor cables installed in ducts under the Lachine canal for 25 kV operations; the same voltage was used for cable traversing the St. Lawrence River in 1906. With some experiences behind them, cable manufacturers were increasingly gaining confidence and during the St. Louis Exposition in 1904 power cables developed for voltages as high as 50 kV were put on display [14]. Oil-Impregnated Paper Power Cables [14] During the period prior to World War I, extensive use was made of oilimpregnated paper cables of the three-conductor belted type for voltages up to 25 kV. Due to non-uniform stress distribution in the cable construction, the belted cable proved to be highly partial discharge susceptible when attempts were made to extend the operating voltage range with larger wall thickness to approximately 35 kV, to meet the increased power demand following World War I [18]. This problem was resolved by shielding the individual conductors, using 3-mil-thick copper tapes. The outside of the shielded conductors was thus maintained at the same ground potential. Figure 1.3.1 Cross-section of an Oil-impregnated Paper Insulated Cable In addition, the belt insulation was replaced with a binder consisting of fabric tapes and strands of interwoven copper wire. The purpose of the latter was again to maintain the shields of the three cables at the same potential. Over the years, the conductor shapes of the three-conductor shielded paper insulated cables have evolved into three forms, namely circular, oval, and sectoral. In many utilities a substantial portion of the present-day distribution load is still carried at 35 kV via three-phase oil-impregnated paper belted cables, with the three conductors individually grounded. There is little inducement to replace these cables with solid extruded dielectric cables, whose outer diameter for an equivalent power rating would exceed that of the ducts accommodating the more compact threephase oil-paper belted cables. Moreover, the oil-paper belted cables have been characterized by remarkably long in-service lifetimes that often exceed 65 years. Belted cables with unshielded conductors are still deployed but only for working voltages equal to or less than 15 kV. With the individual conductors shielded, it was possible to extend the use of the three-phase belted cables for voltages as high as 69 kV, though on the average their application has been confined to voltages below 35 kV. The main reason for this upper limit has again been associated with the occurrence of partial discharges, which had in numerous instances led to the deterioration and failure of the dielectric at the elevated voltages. The partial discharges were found to take place in voids, which were formed either during the manufacturing process or during the load cycling while in service. Solid-Dielectric-Extruded Power Cables [1, 14] With the discovery of the hydrocarbon thermoplastic polyethylene (PE) in England in 1933, polyethylene became rapidly, the insulant of choice for RF coaxial cables. PE was first used as an insulant for power cables in the 1950s. In the mid 1960s, conventional PE became the material of choice for the rapidly expanding URD systems in the United States. It was known to be superior to butyl rubber for moisture resistance, and could be readily extruded. It was used with tape shields, which achieved their semi-conducting properties because of carbon black. By 1968, virtually all of the URD installations consisted of polyethylene-insulated medium voltage cables. The polyethylene was referred to as HMWPE; this simply meant that the insulation used had a very high average molecular weight. The higher the molecular weight, the better the electrical properties. The highest molecular weight PE that could be readily extruded was adopted. Jacketed construction was seldom employed at that time. Extruded thermoplastic shields were introduced between 1965 and 1975 leading both to easier processing and better reliability of the cable [19]. XLPE was first patented in 1959 for a filled compound and in 1963 for unfilled by Dr. Frank Precopio. It was not widely used because of the tremendous pressure to keep the cost of URD down near the cost of an overhead system. This higher cost was caused by the need for additives (cross linking agents) and the cost of manufacturing based on the need for massive, continuous vulcanizing (CV) tubes. EPR was introduced at about the same time. The significantly higher initial cost of these cables slowed their acceptance for utility purposes until the 1980s. The superior operating and allowable emergency temperatures of XLPE and EPR made them the choice for feeder cables in commercial and industrial applications. These materials do not melt and flow like HMWPE. The emergence of power distribution cables insulated with PE have replaced a significant portion of the oil-impregnated-paper insulated power cables used at operating voltages up to 35 kV. But lower voltage PILC cables are still being manufactured, due to their in-service longevity and reliability. In spite the long record of service and reliability of PILC cables, they are being gradually replaced by the less hygroscopic polymeric insulated cables, XLPE. XLPE cables have distinct advantages which are lighter weight, better electrical and thermal properties, less maintenance, and easier terminating and jointing procedure etc. Today, XLPE cables are being extensively used in many countries all over the world. In 1959, Japan and USA commercialized XLPE cables up to medium voltage rating. Since then a fast development of XLPE cables has taken place. Presently, XLPE cable of 500 kV class has been installed in Japan. The introduction of XLPE has increased the capability of polymeric insulated cables because of their higher temperature ratings. XLPE insulations perform well at elevated temperatures. Their normal operating temperature is about 90  °C and designed to withstand an emergency overload and short circuit ratings of 130  °C and 250  °C, respectively. Technology of XLPE Cables XLPE has become the most favored insulant. Germany, USA, Asian and Scandinavian countries have installed gigantic quantities of such cables. Japan has developed XLPE cables up to 500 kV which is the highest voltage rating of XLPE cables manufactured so far. The basic material for XLPE cable is polyethylene (PE). PE has very good electrical properties. However, its mechanical strength decreases significantly above 75  °C restricting its continuous operating temperature to 70  °C only. The improved thermal characteristics of PE are obtained by establishing a large number of cross-links between its liner molecular chains employing suitable techniques. The introduction of XLPE has increased the capability of polymeric insulated cables because of their higher temperature ratings. The processes for converting PE to XLPE are electron irradiation, chemical cross linking, and organic silane method. Electron irradiation is a slow process and it is difficult to ensure an even degree of cross linking throughout the thick insulation required for power cables. Therefore this process is usually restricted to thin insulation of 1 to 2 mm thickness only. Chemical cross linking process is the process by which cross-linking of PE is established using organic peroxide such as dicumyl peroxide (DCP) at high temperature in the range 250 to 350  °C and pressure 15-20 kg/cm2. This method is employed in the production of XLPE cables of all voltage range, from LV to EHV. Sioplas technique is a relatively new method of cross linking PE into XLPE. Cross linking is achieved by mixing suitable silane to PE and exposing this to ambient conditions. This method has the distinct advantage of lower capital expenditure as no special arrangements to maintain high pressure and temperature are required. But the process is very slow for thick insulation and hence restricted to low voltage and medium voltag e XLPE cables. The general construction of XLPE cable consists of copper or aluminium conductor, extruded layer of semi conducting material over conductor (for voltage class above 3.3 kV), extruded XLPE insulation, extruded layer of semi-conducting material (for cables of voltage rating above 3.3 kV), copper wire or tape as metallic screen, armour, inner sheath and outer sheath, usually made of PVC etc. Three core XLPE cables are generally used up to maximum 33 kV. Cables of 66 kV and above voltage rating are of single core construction. Figure 1.3.2 Solid dielectric extruded power cable [14] The manufacturing process of XLPE cables consists of mixing of PE with cross-linking agent (DCP) and antioxidants, extrusion of semiconducting layers and insulation over the conductor, crosslinking the PE compound in curing lines at high temperature and pressure and cooling the core to ambient temperature. All these processes are carried out in one step employing catenaries lines for curing and cooling, hence the name continuous catenaries vulcanization. Semiconducting layers and insulation are extruded using triple extrusion technique. The curing process was initially carried out with steam at high temperature and pressure. This resulted in the formation of microvoids within the insulation and restricted the application of steam curing process up to 33 kV. To achieve reliable HV cables, it was therefore necessary to employ curing in the absence of steam. For this reason, dry curing methods were developed, where PE was crosslinked under nitrogen pressure in silicone oil, in molten salt and also in long dies. The numbers of microvoids were drastically reduced. A new curing process has recently appeared namely silane process which is more economical. Losses in Power Cables Losses in power cables include losses in conductor, insulation, sheath, and screens armors. Conductor losses (I2Rac losses) depend upon the rms current I effective AC resistance of the cable conductor. Dielectric losses comprise of losses due to leakage through the cable insulation and caused by dielectric polarization under AC stresses. It includes the net dielectric losses depend upon cable voltage, its frequency as well as the permittivity and loss tangent of the cable dielectric material, as shown by the equation below: Power loss = à Ã¢â‚¬ °CoV2ÃŽÂ µr tan ÃŽÂ ´ [2] (1) Generally, tan ÃŽÂ ´, which partially controls the dielectric losses, is significantly higher for oil-paper insulation as compared to XLPE insulation. For most of the dielectric materials used in cables, tan ÃŽÂ ´ depends upon temperature, applied stress and supply frequency. For oil-paper insulation tan ÃŽÂ ´ is also strongly influenced by moisture content. Therefore, in voltage cables, a moisture level of less than 0.05 % is desirable in order keep dielectric losses within acceptable limits. The presence of voids and microcracks can also influence dielectric losses. These voids are formed in the insulation or at the screens/insulation interfaces during manufacture, installation or operation. In polymeric cables, they are formed during the extrusion process while in paper-insulated cables, during the impregnation cycle. Voids may also form in cables by the differential expansion contraction of cable materials due to cyclic loading or short circuit conditions. These voids have a higher electric stress as compared to the bulk insulation. However, the gas inside a void usually has lower breakdown strength as compared to the main insulation. When the electric stress in void exceeds the breakdown strength of gas within the void, PD occurs. Any partial discharge in such voids increases the effective tan ÃŽÂ ´ value for insulation. Consequently, when the applied voltage is raised above the charge inception threshold, the dielectric losses exhibit a distinct increase. Similarly, impurities in the cable insulation and screening materials also increase dielectric losses. The AC current flowing along each cable conductor induces emf the metallic sheaths of the cable. Without grounding, such sheaths would operate at a potential above the ground potential and can pose a hazard. Furthermore, it will accelerate degradation of the jacket and materials, thereby affecting the cables life and reliability. When the sheaths are bonded, circulating current flows in them causing power losses. However, for three-core cables such losses are negligible. In addition to circulating currents, eddy currents are also induced in sheaths of both single and multi-core cables causing additional losses which usually are of small magnitudes. 1.5 Objectives of Study This project is conducted to evaluate the expected value of aging cost due to harmonic losses in XLPE cables. Therefore, this project is conducted regarding to these objectives: To investigate the effects of harmonics losses on XLPE cables from economical point of view. To evaluate the expected value of the aging cost due to harmonics losses in XLPE insulated cables. 1.6 Scope of study This study will focus on XLPE insulated cables This study will use the characteristics of single core underground cables. The effect of harmonics losses on XLPE cable will be investigated A program will be developed to evaluate the expected value of aging cost due to harmonic losses. The economical damage due to harmonic losses is quantified by means of the expected values of the operating costs and of the aging costs. For this, it will focus only for the calculation of the expected values of the aging costs. CHAPTER 2 LITERATURE REVIEW 2.1 Introduction We design power systems to function at the fundamental frequency [1]. In Malaysia, the fundamental frequency is standardized at 50 Hz. This design is prone to unsatisfactory operation. At the same time, failure will happen when subjected to voltages and currents those contain substantial harmonic frequency elements. Frequently, the electrical equipment may seem operate normally. However, when they operate under a certain combination of conditions it might enhance the impact of harmonics which cause results to damage [20]. Most people do not realize that harmonics have been around for a long time. Since the first AC generator began to operate more than 100 years ago (Sankaran, C., 1995), electrical power systems have experienced harmonics. When harmonics present in electrical equipment, it can cause the equipment to malfunction and fail to work. In this case proper design and rating are needed to prevent the presence of harmonics. 2.2 Power System Harmonics The objective of the electric utility is to deliver sinusoidal voltage at fairly constant magnitude throughout their system. In fact, in order to achieve this objective is reasonably complicated because there are loads that exist on the power system that will produce harmonic currents. These currents produced may result in distorted voltages and currents that can give negative impact to the system performance in different ways. As the number of harmonic producing loads has increased over the years, it has become increasingly necessary to address their influence when making any addition or changes to an installation. We should consider two important concepts that have to bear in mind with regard to power system harmonics. The first concept is the nature of harmonic current producing loads (non linear loads) and the second concept is the way in which harmonic currents flow and how the resulting harmonic voltages develop. Ideally, voltage and current waveforms are perfect sinusoids. However, because of the increased popularity of electronic and other non-linear loads, these waveforms quite often become distorted. This deviation from a perfect sine wave can be represented by harmonics sinusoidal components having a frequency that is an integral multiple of the fundamental frequency. Thus, a pure voltage or current sine wave has no distortion and no harmonics, and a non-sinusoidal wave has distortion and harmonics. To quantify the distortion, the term total harmonic distortion (THD) is used. The term expresses the distortion as a percentage of the fundamental (pure sine) of voltage and current waveforms. In addition, current harmonics can distort the voltage waveform and cause voltage harmonics. Voltage distortion affects not only sensitive electronic loads but also electric motors and capacitor banks. 2.2.1 Definition of Harmonic Harmonics are defined as current and voltages at frequencies that are integer multiples of the fundamental power frequency [4]. For example, if the fundamental frequency is 50 Hz, then the second harmonic is 100 Hz, the third is 150 Hz, and etc [5]. The presence of harmonics in electrical energy systems is well recognized due to nonlinear loads such as static converters and it can damage the system components [6]. These nonlinear loads will draw current in abrupt pulses rather than in a smooth sinusoidal manner. Then, these pulses cause distorted current wave shapes which in turn and cause harmonic currents to flow back into other parts of the power system. In the case of power cables, harmonics can cause relevant additional losses in the conducting and in the insulating materials which cannot be neglected in the cable size [6]. 2.2.2 Source of harmonics Most harmonics originate from the generation of harmonic current caused by nonlinear load signatures [4]. The major sources of power system harmonics include switching operations, power electronic devices and other nonlinear loads and etc [7]. Electronic devices are nonlinear and thus they create distorted currents even when supplied with a purely sinusoidal voltage. As nonlinear currents flow through a facilitys electrical system and the distribution-transmission lines, additional voltage distortions are produced due to the impedance associated with the electrical network. Thus, as electrical power is generated, distributed, and utilized, voltage and current waveform distortions are produced [8]. As the number and ratings of power electronic devices connected to the power systems increase, the harmonic currents injected into power system and the resulting voltage distortions have become a major problem for power quality. This is the current issues that always be taken into account nowadays. Furthermore, the installation of power factor improving capacitors may lead to resonance conditions that amplify specific harmonic currents flowing into transformers and generators. On the other hand, large industrial ac motors may also provide a path for the harmonic currents. These currents can cause overheating problems for the motors, generators, and transformers. Power grid connected electric devices which can generate harmonic currents in the power system include fluorescent light ballast transformers, induction motors, incandescent light dimmers, overexcited transformers, arc welding equipment, AC/DC rotary converters, battery chargers, computers, and any type of device that utilize s rectified AC power to drive DC equipment [9]. 2.2.3 The Harm of Harmonics Harmonics only mean trouble if the power system is not well designed to handle them. High harmonic neutral currents are a problem only if the neutral is not properly sized. Current harmonics are not a problem to a transformer if it is derated appropriately. Even some voltage distortion below 8 % THD at the point of utilization is acceptable as long as sensitive equipment is not affected. However, it is always important to be aware of the presence of harmonics and to try to minimize them by purchasing low distortion electronic ballasts and reactors for PWM ASDs. This will not only keep the harmonics in check and improve the power factor in the facility, but will also save energy by reducing losses on power system components. In addition, any time there is a considerable increase of non-linear loads, it is important to check power system components to prevent problems. 2.2.4 Effects of Harmonics on Power System Harmonic currents and voltage distortion are becoming the most severe and complex electrical challenge for th

Brazil socio economy Essay

Brazil is one of the South American countries and the fifth largest country in terms of geographical area. It has population of over one hundred and eight three million people. The Brazil’s natural resources largely includes gold, iron ore, manganese ,bauxite platinum, tin ,uranium, timber and petroleum among others. In most part of Brazil’s history, it has experienced very slow economic growth. For instance, during the colonial period sugar, gold and slavery did not boost the economy of the country. In fact, in mid-eighteenth century, Brazil’s economy retardation did worry Portuguese rulers. During the time of independence, Brazil had one of the least productive economies in the western hemisphere than any other New World colony. After the independence it did not show much progress. When the industrial revolution seemed to gather momentum, imperial Brazil economy was stagnating. As slavery ended marking the fall of the empire, its per capita Gross Domestic Production (GDP) was less than a half that of Mexico and making one sixth of the United State. This show some improvement from 1913 to 1980 where it sustained significant economic growth though interrupted by the Great Depression in early years. However, over the past quarter century, its economy has barely grown. Each time it makes attempt to rise it falls back. Similarly, its social inequality has also been historical. Social inequality has been there through different periods, in various economic models, in dictatorships and in democratic transitions. Therefore, the main purpose of this presentation is to discuss reasons which that have contributed to social inequality and economical stagnation in Brazil. From 1500 to late 1930s, the Brazilian economy relied heavily on the production of primary products for export. In fact, its economy assumed colonial master policy that was sternly enforced during its reign that for about three centuries has curbed the development that lasted past independence. There were some changes that occurred when slavery was abolished and waged labor adopted. First important structural transformation steps were recorded in 1930 when Brazil changed into a modern, semi-industrialized economy. They were intensely felt between 1950 and 1981 when economic growth rates remained quite high with establishment of diversified manufacturing base. After World War II rapid socioeconomic transformation took place. But since early 1980s, Brazil’s economy has been encountering economic huddles that have seen it have very slow growth if not stagnation. When second oil shock stuck in 1979, the prices of oil importation in Brazil double and this had effects on trade in that it lowered terms of trade further. The increase in world trade rates caused rise in Brazil’s balance payments and size of foreign debt though country did not stop borrowing meanwhile it tried to maintain high-growth strategy. In start of 1980s, foreign debt became so acute which led to introduction of program that could generate growing trade in surpluses so that country could amortize the foreign debt. This was achieved by reducing imports and expansion of exports. Consequently, real gross domestic production declined. Mexican debt crisis of 1981 blocked Brazil’s access to international financial markets that caused much pressure for its economic adjustment. Structural Adjustment Plan was introduced by International Monetary Fund that enabled the country to meet interest payments on the debt. However, this subsequently resulted in much of economic decline compounded with high inflation rate. It happened that, inflation accelerated further due to a combination of number of factors namely the exchange –rate devaluations of austerity program, growing public deficit and escalating indexation of financial balances and wages among others. The exchange –rate devaluations of the austerity program and growing public deficit formed a classical cause of inflation. Nevertheless, increased indexation of financial balances and wage were just important mechanism for propagating inflation. At around mid 1980s, foreign debt was almost displaced by domestic debt that caused main economic problem. Previously, during period of high economic growth in 1970s, considerable portion of foreign borrowing was done by state enterprises which were the main actors in the import-substitution industrialization strategy. At first they borrowed with intention of financing their investments but later due to acute shortage of foreign exchange they were compelled by the government to borrow unnecessarily and thus increasing their debts greatly. This was worsened by the sharp increase of international rates. This followed that because the state enterprises were not supposed to go bankrupt; their debt burden was borne by the government which further increased the public debt. Coupled with disorganization of the public sector, public debt was transformed in to a big economic problem. By the end of 1980s it was necessary for large-scale fiscal reform that could result to non-inflationary financing of the public sector not only for inflation control purposes alone but also restore the public sector’s capacity to be able to invest for overall economy recovery. But this was hampered by political challenges which could not make any reform to materialize. Several attempts were mounted to bring down inflation which was the most visible symptom. There were referred to as ‘heterodox economic shocks’ namely Cruzado Plan, the Bresser Plan and the Summer Plan that came in succession in each year from 1987 to 1989 respectively. These plans did no make the situation any better. By the start of 1990s, the country was ushered into a new era that probably radiated some hope to recovery of the economy that was marked by the first post-military president Fernando Collor de Mello in March 1990. Hyperinflation and virtually bankrupt public sector was the first things he had to fix with his new administration. But preceding events could not promise any good outcome to mobilize stagnating economy. Two years later, the President Collor de Mello was impeached on corruption charges. Therefore, it is evident that the ‘undeveloped’ of Brazil’s economy has been caused by several factors. Brazil’s geographical position is one of the factors that have contributed to its slow economic growth. This is because most of it tradable natural resources are too far from potential markets for profit exploitation. For instance, during the colonial period major export was sugar which had to be produced within fifteen miles of a port or navigable river. But the huge Amazon River system flows through vast tropical forest where land is unfertile and there were no navigable rivers that were flowing where export crops could be produced using modern scientific farming methods. Brazil though had a long coastline a few were protected harbor and without railways or truck, what was produced in interior was cattle and slaves that walked to the market The same challenges face the country even today. The issue of poor transport is affecting the Brazil’s industries considerably. The government has often failed to meet export target due to the country’s transport problem and shipping of the production. Logistically, it has proven that even though it was to transport, the operating cost would increase the merchandise prices and hence lose in world market. This greatly removes Brazilian competitive advantage and makes it not to earn sufficient foreign exchange to boost it economy. World Bank has reveled that transport expenses account for about thirty five percent of the operating cost . This adversely affects even private companies. This generally had resulted to chronic lack of investment that has caused country’s economy not to develop. Another important factor to economy growth failure is the effects of the International Monetary Fund’s structural adjustment policy that trace way back to the 1980s. When the Brazil foreign debt happened to be high and was challenging to service it, International Monetary Fund to help the country, it introduced Structural Adjustment Policy which acted as stabilization program. However, it was designed from an orthodox monetarist perspective whereby it prioritized debts solvency through fiscal austerity and failed to address the core problem of Brazil’s economy. It did not curb rising inflation or initiate significant economic growth; rather it created hardship in the country. Another cause of the economy’s failure to thrive in Brazil is leadership. Brazil political leadership was characterized by emperor, politicalmachine, dictator, military authoritarianism, several military coups and impeachment leaderships. Most of these leaders’ agenda did not feature Brazil’s interest in their hearts as they establish themselves. Consequently this has made country economy to retrogress. Lastly, concentration of wealth to few minorities has perversely affected the Brazil’s economic growth. It has been observed that income inequality distribution in Brazil is one of the most unequal in the world. This has caused high poverty rates, chronic malnutrition and preventable disease that have caused the economy to drag. It is true that Brazil is socially unequal. It has been recorded to be one of the nations with high rate inequality. Its income inequality measurements according to the United Nations Development Program (UNDP) are relatively higher than even some of very poor African countries such as Lesotho, Namibia or Sierra Leone and yet it belong to the wealthiest countries. The country has high income concentration that reveals that about one percent of the population belong to the richest which constitute to less than two million of the total population having approximately thirteen percent of all of household income. These results of poverty level have shown inconsistency in regards to its economic size. According to the Institute for Applied Economic Research (IPEA) data, about thirty percent of the population with is equivalent to fifty four million people are considered to be poor. Within this same group, about twenty million people that account for almost twelve percent of the population are ranked as been extremely poor. As it can be seen, this poverty level is higher than the average ten percent in countries with a per capita income similar to that of Brazil or those countries which have a poverty level three times less than Brazil. Inequality is more pronounced in the rural areas whereby small number of large owners such as large farmers, large rural entrepreneur who are seen to monopolize most of the rural areas coexist with thousands of small land owners, landless workers and rural workers who live in precarious conditions. From the start, there exists high level of land inequalities which continues to escalate. It has been found that, the percentage of the total area occupied by the ten percent largest properties is about seventy eight percent. Similarly, there is also a gap between the rich and the poor in urban areas in which more than eighty percent of the Brazilians live presently. A good percentage of urban dwellers are living in poor conditions without proper housing and access to public equipment and public health and recreation facilities among others. Access to housing also remains highly unequal based in regional basis. For instance, while in southern region and southwest region housing conditions are approximately thirty one and twenty seven percent respectively, this percent rises to about seventy percent in the northern region and sixty percent in mid-west region. At the same note, there is also serious problem in the housing deficit whereby it is estimates that close to eight million units with ninety percent of housing deficit mainly affect poor families with an income of barely three minimum wages in a month. From this brief analysis, poverty in Brazil is associated with color and location that is, it affect the black and is concentrated in northeast region. This is because, two-thirds of all the poor in Brazil are block and seventy percent of the total population living in the in poverty are city dwellers and close to fifty one percent belong to such population who are living in northeast region. The main cause of inequalities discussed above is not due to general lack of the resources but rather it is caused by their imbalanced distribution of resources. Such inequalities in contemporary democracies seem to be attributed to tensions that exist between the ethical requirements related to ‘right’ and the importance of economic effectiveness; between the legal order that promises equality and the realty of the exclusion which is brought about by the exercise of power. It is in historic records that in many of western countries there was a period when social disparities were so extreme such that society had to mobilize government mechanisms, through laws, public policies and changes in tax system that saw some degree of redistribution to eliminate the extreme forms of poverty and inequality that existed. However, in Brazil since it was a colony, empire and then a republic it has never had attempts to promote inclusion of the poorest segments of the population. It developed in all of twentieth century with considerable number of extremely poor people. Such development process that ‘manages poverty’ is referred to as a ‘conservative modernization’ by development experts which is model that describe a situation which produces significant changes in the economy without altering established socio-economic order by affecting it slowly. In social perspective, conservative modernization implies several things for instance, lack of regulation in labor market. Nearly more than half of the working population that comprises of about forty five million male and female workers do not enjoy any labor rights such as unemployment insurance, invalalidity insurance cover, paid vacation, maternity and paternity leave, family allowances and pensions. This translates that even though the country belong to the world’s wealthiest counties, it has not ensured formal wages and minimum social protection to many of its workers. Another consequence of social inequalities in Brazil is due to low level of schooling. Universal access to quality education has not given a priority in Brazil. Presently, illiteracy level rates at about ten percent. Subsequently, the average number of years of schooling of the population aged fifteen and above is estimated to be seven percent when it is suppose be legally at least eight years. Despite the fact that there is improvement as observed from the indicators, the quality of education has long way to go. In rural area, the conservative approach is also felt particularly in agribusiness which is found to strengthens the economic power of large landowners while it neglect the unskilled wage-earning labor force and many small farmers that are not incorporated into the prevailing agricultural model. In large cities exclusion process also has taken its toll where major changes in production process and in the appropriation of urban space have synergetic effects. Their effects are reflected in social spatial restructuring processes that seem to enhance the segregation problem or what in other term would rightly be referred to as ‘social apartheid’. In such situation a significant proportion of the population is forced to live not only outside the formal labor market but also without access to proper housing and basic public services that are vital for quality life such as sanitation, education, health care, transport and recreation. Another cause of inequality is regressive tax system that heavily imposes a burden on the consumption and labor while on the other side spares the large capital. The data collected by the Brazilian Institute for Geography and Statistics (IBGE) in 2004 indicated that the tax load for the richest segment of the population who earned more than thirty minimum wages in a month accounts for about twenty six percent of the family income while the country’s poorest workers, for those with income of less than two minimum wages had a tax load which was nearly twice high- about forty nine percent. The worrying thing is that this situation is worsening over time. The same logic is found in spending of social policies that has been systematically diminishing. For instance, a decade ago there was a mechanism that was established that could allow the Federal government to withhold twenty percent of all the taxes and contributions allocated for social actions which mounted to billions of reals that were used every year to ensure the required surplus for paying interest on and repay the country’s debt. This largely contributed to inquality as the wealthiest- public debt creditor, are favored while the assistance provided by the government to the poorer population was reduced significantly. Social inequality does not only confine itself between the poor and the rich but also it is gender and race based. There is exclusion experienced by women and black people that is directly related to sexist and racist phenomena. Gender and race inequalities that has persisted for decades is an indication that individuals continue be discriminated based on their sex or color in spheres of society like in schools, labor market, political circles and family . The consequences of these perpetuated inequalities are perverse in that they make situation to look normal which in turn reinforce the stigmatization of these marginalized groups. This hinders individuals to achieve their potential and also prevents them exercise their right as Brazilian citizens. The exclusion processes that women encounters and the black people that has widened social gap is what has characterizes contemporary Brazil society. Bibliography: Beghin, N. (2008); Notes on Inequality and Poverty in Brazil: Current Situation and Challenges. Retrieved on 8th January 2009 from: http://www. oxfam. org. uk/resources/downloads/FP2P/FP2P_Brazil_Inequality_Poverty_BP_ENGLISH. pdf Brazil Historical Background and Economic Growth (2009);http://www. floridabrasil. com/brazil/guide-about-Brazil-Economy-Historical-Background-Economic-Growth. htm Coatsworth, J. H. (2007); Why is Brazil â€Å"Underdeveloped†; Retrieved on 8th January 2009from:http://www. drclas. harvard. edu/revista/articles/view/934. Hamilton, C. V. (2001); Beyond Racism: Race and Inequality in Brazil, South Africa, and the United States. ISBN 158826002X, 9781588260024Lynne Rienner Publishers. Nathalie B. (2008); Notes on Inequality and Poverty in Brazil: Current Situation and Challenges. Retrieved on 8th January 2009 from: http://www. oxfam. org. uk/resources/downloads/FP2P/FP2P_Brazil_Inequality_Poverty_BP_ENGLISH. pdf Saddi, V. (2008); Lack of Infrastructure Investment in Brazil: A Constraint on Economic Growth; Retrieved on 8th January 2009 from:http://www. rgemonitor. com/economonitor-monitor/253645/lack_of_infrastructure_investment_in_brazil_a_constraint_on_economic_growth Weyland, K. G. (2002); The Politics of Market Reform in Fragile Democracies: Argentina, Brazil, Peru, and Venezuela. ISBN 0691096430, 9780691096438, Princeton University Press Wise, C. (2003); Reinventing the State: Economic Strategy and Institutional Change in Peru. ISBN 047211316X, 9780472113163, University of Michigan Press.

The Level Of Concentration Is High - 1314 Words

With my research I found that the level of concentration is high enough to suggest that some markets within the construction industry can be considered oligopolistic. It is important to remember that the market structure is only one characteristic of various factors which affects the performance of firms concerned. My research found that within the Materials and components grouping 13/24 markets are oligopolistic. 2/9 is oligopolistic within the Professional consultancy, 2/11 within Plant and equipment and 6/10 in the Energy and supplies group. This helps me to conclude my thoughts in that the level of concentration is high enough to suggest that some markets within the construction industry can be considered oligopolistic. Commercial confidentiality has been a factor in my research as it has prevented me from gaining full access and data required to fully investigate the matter at hand. Therefore some information for certain groupings has been withheld to prevent commercially sensitive data collected by the ONS to be made available to competitors. When this occurs, it is usually a taken as the market being fairly concentrated. There are some obvious irregularities such as ‘Agriculture’ which is listed as ‘not available’ regardless of the fact that it is included within the list of 10 least concentrated sectors. Within the Materials and components group, concrete and stone products are seen to be the largest single sector which is supplying materials to construction.Show MoreRelatedConcentration Levels Of High School Students Chewing Gum Versus Non Chewers1215 Words   |  5 PagesAbstract: The purpose of this experiment was the find the difference between concentration levels of high school students chewing gum versus non-chewers. The concentration portion provided students with two color tests to take to record differences in concentration. 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Ethical Dilemma at Northlake Essay - 1906 Words

â€Å"Ethical Dilemma at Northlake† Week 3 – Case Study # 1 Synopsis: The case begins with Jim McIntoch the vice president of finance of Amalgamated Forest Products having a conversation with Frank the manager of corporate reporting. Jim is upset with Frank and is confronting him about the decision he’s made about going public about a financial analysis report that Amalgamated Forest Products will present to the legislation. Frank is stating that the report is falsifying information about the how much the operating cost would be if the company would need to establish pollution control of the discharge of wastewater. Jim is extremely upset and basically threatens him about ruining his career as well as the company if he were to go public†¦show more content†¦In return Frank adds that his issue is not only with overstating the operating cost, but also that the company is hiding the fact of the damage they did when dumping waste into the Wanawashee River and how it has affected many people in the community and still till the da y people are drinking polluted water from their doing. He also points out they can all face jail time if it’s discovered that they were involved in the polluting of the river. The dumping of the wastewater has serious implications not only for the company but also for the many innocent people who are drinking the water that is polluted. Jean as the president of the company should be using the six factors of â€Å"Ethical Intensity† (38-40). He needs to take into consideration the magnitude of the consequences that will be done if he insists with presenting an incorrect analysis. It’s clear the company really does not follow a code of conduct and as a leader of the company he should understand the social consensus especially of the town of Northlake which has a population of 10,000. How they would view the company if it was discovered what it did. There needs to be a change in the company on its view on ethical principles. Frank also needs to remind both Jean and Jim the laws set in place against retaliation against whistle blowing. Its clear HR needs to get involved and possible he may need to get someShow MoreRelatedEthical Dilemma at Northlake.1659 Words   |  7 Pagesindustry to implement emission controls. Jean Letourneau, the 60 year old company president of Amalgamated is the appointed industry spokesperson and will appear before the legislative committee. Under oath, he Week 3 Case Study #1 – Ethical Dilemma at Northlake will testify to the report’s legitimacy. Jean agrees with the report and feels having to build a lagoon for wastewater treatment will be to the detriment of his company and the industry will suffer even further in this already decliningRead MoreEthical Dilemma at Northlake1898 Words   |  8 Pagesâ€Å"Ethical Dilemma at Northlake† Week 3 – Case Study # 1 Synopsis: The case begins with Jim McIntoch the vice president of finance of Amalgamated Forest Products having a conversation with Frank the manager of corporate reporting. Jim is upset with Frank and is confronting him about the decision he’s made about going public about a financial analysis report that Amalgamated Forest Products will present to the legislation. Frank is stating that the report is falsifying information about the howRead MoreEthical Dilemma at Northlake Essay example1136 Words   |  5 Pagesâ€Å"Ethical Dilemma at Northlake† Week 3 – Case Study #1 Cecellia Dantzler Synopsis: Frank, manager of corporate reporting at Amalgamated Forest Products, has threatened to go public with information regarding a falsified report on the effect of effluent controls on the discharge of wastewater from pulp and paper companies, which has angered his boss, Jim McIntosh and the company’s president, Jim Letourneau. Letourneau was to testify before a legislative subcommittee the following week and useRead MoreEthical Delimma at Northlake935 Words   |  4 PagesEthical Dilemma at Northlake Synopsis Frank is the manager of corporate reporting at Amalgamated Forests Products. He had objected to the report Endangered Species: The Pulp and Paper Industry in the Upper Peninsula, this report contained the industrys response to the new governments proposals to control effluents from being discharged into environmentally sensitive regions. Amalgamated Forests Products had taken a lead in presenting the perspective of the five pulp and paper companies in