Monday, January 27, 2020
Maglev Wind Turbine and Solar Panel for Streetlight
Maglev Wind Turbine and Solar Panel for Streetlight Abstract: This work describes the implementation of VAWT and solar panel for electricity generation from renewable energy sources that are wind energy and solar energy respectively. The VAWT worked on electromagnetism principle has suspension system of permanent magnets instead of ball bearing used in conventional wind turbines. The electrical energy generated by this hybrid system is then used for streetlight purpose. Keywords: Wind energy, Solar energy, Magnetic Levitation, VAWT, Savonius Turbine, Solar panel 1. INTRODUCTION The primary factor for survival of human beings is the energy. Everything what happens in the world is the expression of flow of energy from one form to another. Electric power is not available in many rural areas due to high cost of generation and distribution to small dispersed users. For electricity generation we have to greatly depend upon hydraulic and nuclear power plants. But due to their certain disadvantages like area compensation, high initial cost, availability of resources and also the pollution, there is need to rethink on some another renewable energy resources. Solar energy and wind energy are available abundantly all over the world with free of cost. These energies are harnessed by human beings for a long time and with the advanced technologies we can take their advantage to generate electricity. The potential of solar energy is 178 billion MW which is about 20000 times the worlds demand and the potential of wind energy is 1.6ÃÆ'-107 MW equal to magnitude of present energy consumption on the earth. The solar energy can be converted to electrical energy by photovoltaic cells. The kinetic energy of wind can be converted to electrical energy by wind turbine. As conventional wind turbine has certain disadvantages; vertical axis wind turbines (VAWT) are the alternate solution. The merits of VAWT are low initial and running cost, easy installation, less space acquired, capability to capture wind from any direction and elimination of ball bearings by the use of magnetic levitation technique. The advantage of these two renewable energy resources can be taken by making a hybrid system so we do not required depending on availability of any single resource. The electricity required for domestic purpose can be generated by unique combination of solar system and wind system. 2. LITERATURE REVIEW 2.1 Solar power The solar power where sun hits atmosphere is 1017 watts, whereas the solar power on earths surface is 1016 watts. The total world-wide power demand of all needs of civilization is 1013 watts. Therefore, the sun gives us 1000 times more power than we need. If we can use 5% of this energy, it will be 50 times what the world will require. 2.2 Principle of working of photovoltaic cell Electricity can be produced from the solar energy by photovoltaic solar cells. When photons from the sun are absorbed in a semi-conductor, they create free electrons with higher energies than the electrons which provide the bonding in the base crystal. Once these free electrons are created, there must be an electric field to induce these higher energy electrons to flow out of the semi-conductor to do useful work. The electric field in most solar cells is provided by a junction of materials which have different electrical properties. The photovoltaic effect can be easily described easily for p-n junction in semi-conductor materials of solar cells which are silicon, cadmium, sulphide/copper sulphide , gallium arsenite. Fig-1 Working principle of photovoltaic cell 2.3 Various type of solar cell Thecomparison of various types of pv-cell is Price Efficiency 1 W size Current production Single crystal High 10-17% 1 About 30% Polcrystalline Medium 10-13% 1.3 About 60% Amorphous Low 7-10% 1.7 About 10% 2.4 Wind energy Wind energy is an indirect source of solar energy. Factors responsible for wind are- 1. Heating and cooling of the atmosphere which generates convection currents. Heating is caused by the absorption of solar energy on the earths surface and in the atmosphere. 2. The rotation of earth with respect to atmosphere, and its motion around the sun. 2.5 Wind power Three factors determine the output from wind energy converter- 1. The wind speed 2. The cross section of wind swept by rotor, and 3. The overall conversion efficiency of rotor, transmission system and generator or pump. No device, however well designed, can extract all of the winds energy because the wind would have to be brought to a halt and this would prevent the passage of more air through the rotor. The most that is possible is for the rotor to decelerate the whole horizontal column of intercepted air to about one-third of its free velocity. A 100% efficient aerogenerator would therefore only be able to convert upto a maximum of around 60% of the available energy in wind into mechanical energy. Well-designed blades will typically extract 70% of the theoretical maximum, but losses incurred in the gear box, transmission system and generator or pump could decrease overall wind turbine efficiency to 35% or less. The wind mill works on the principle of converting kinetic energy of wind to mechanical energy. The mass of wind is- à ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦.. (1) Kinetic energy of wind is- Watts à ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦ (2) But, the power is nothing but kinetic energy of wind. Hence, available wind power- Watts Watts à ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦Ãƒ ¢Ã¢â€š ¬Ã‚ ¦.. (3) Where, A= area swept by the blades, m2 V= velocity of wind, m/s à ªÃ‚  ¬= air density (1.225 kg/m3 at sea level) 2.5 Types of VAWT 1. Savonius rotor Characteristics of Savonius rotor Self-starting Low speed Low efficiency. Advantages: The machine performs at low wind velocity ranges. It has simple construction, hence easy to manufacture. Cost of VAWT may be significantly lower than that of standard wind turbine. Ground level mounting. Overall weight of the turbine may be substantially less than of conventional system. Disadvantages: This type of machine is too solid, having so much metal It is not useful for a very tall installation because a long drive shaft problems. 2. Darrieus rotor Characteristics of Darrieus rotor Not self-starting High speed High efficiency Potentially low capital cost Advantages: Rotor blades can accept the wind from any direction Ground level mounting Eliminate yaw control mechanism Less airfoil fabrication cost Disadvantages: It requires external mechanical source for start up At low height, it experiences a lower wind velocity compare to conventional turbines 3. MAGNETIC LEVITATION 3.1 Principle As we know that, when two like poles of magnet are bring together, they get repels from each other. This characteristic of magnet is used for the suspension purpose in vertical axis wind turbine. Due to the absence of physical contact between magnetic bearings, there is benefit of no friction and hence no wear. Also the no need of lubrication, no power loss and the absence of noise generation. Fig-2 Principle of Magnetic Levitation 3.2 Magnet Selection The strength of magnet to get attract or repels is depend on its material configuration. There are basically four categories of magnet that are alnico, ceramic, samarium cobalt and neodymium iron boron (Nd-Fe-B). Nd-Fe-B is the newest invention out of these which exhibits strongest magnetic properties. This magnet is used for the suspension purpose in VAWT. The repelling force exerted by these magnets holds the weight as well as force exerted by wind turbine. Fig-3 B-H curve of different magnets [1] From figure B-H curve depicts attractive magnetic characteristics of Nd-Fe-B offering high flux density with the ability of resisting the property of demagnetization. The permanent magnets selected were N-42 grade Nd-fe-B having ring shape which consist of nickel plating for strengthening and protecting the magnet. 3.3 Magnet placement To obtain thenecessary suspension for wind turbine, two ring shaped Nd-Fe-B magnets are arranged at the middle of the shaft. Magnetic suspension leads to frictionless, noiseless, maintenance less and power loss less rotations of rotor over stator. The similar 8 number of Nd-Fe-B disc shaped magnets are located around the bottom side periphery of wooden disc at above the top magnet. The flux generated by these disc shaped magnets is used for power generation with the help of the generator. Fig-4 Placement of ring magnet on turbine shaft Fig-5 Placement of disc magnets on rotor 4. COIL DESIGN AND ITS ARRANGEMENT To design the definite number of turns per coil is difficult. If the more turns are wound it increase the emf generated from each coil but increase the size of the every coil. For minimizing the size, wire having higher gauge can be used. If the diameter of wire is small low amount of current will flow leading to heating ofwire because of the increased resistance of wire which is another difficult task. Field density is the problem attached with large size coil for designing the generator for given application. Increase in gap between two magnets by increasing height of coil results in reduction of magnetic flux. Hence necessary voltage and current must be balanced. Fig-7 Coil arrangement on stator 5 HYBRID SYSTEM Sometimes due to unavailability of any single resource that is either solar energy or wind energy, there is effect on efficiency of such system. Also to decrease the load on single system, we can interconnect the solar system and wind system together. The output of solar system is DC and that of wind system is AC. So by the use of rectifier AC can be converted to DC and finally this combined DC is given to battery for storage purpose. Fig-8 Hybrid system 6. ENERGY STORAGE When there is no need of generated electrical energy or when the generated energy is excess than demand for application, there is need to store electrical energy. Therefore a 12V battery is used for storage purpose. The electrical energy is stored in the battery in the form of chemical energy when not to used and get convert from chemical energy to electrical energy When required to be used. 7. CONCLUSION The efficiency and effectiveness of VAWT increases due to the use of magnetic levitation principle. For domestic application it is convenient to use Maglev turbine than to use conventional turbine as it requires less space and also low initial and maintenance cost. Maglev turbine with large capacity gives more power than conventional horizontal axis turbine. To decrease the load on any single system, the concept of interconnection of solar and wind is very helpful. This hybrid system along with streetlight application can be used for several domestic applications like mobile and laptop charging, CCTV, to enlighten the single room etc. Use of renewable energy sources with initial investment can make the user free from electricity bill. 8. REFERENCES [1] Harshal V. and Kharat R. K, Power generation using Maglev Windmill International Journal of Research in Engineering and Technology (IJRET) Volume: 05 Issue: 06 June: 2016 [2] Ashvin P. Joseph Review paper on Wind Turbine using Magnetic Levitation International Journal of Research in Engineering and Technology (IJRMET) Volume: 6 Issue:1 Nov 2015-April 2016 [3] G. D. Rai, Non-conventional energy sources Khanna publishers, fourth edition, 2008 [4] B. Bittumon Design and analysis of Maglev Vertical Axis Wind Turbine International journal of emerging technology and advanced engineering (IJETAE) Volume: 4 Issue: 4 April 2014
Sunday, January 19, 2020
Nietzsche: Exposing the Christianity Hoax Essay -- Nietzsche Philosoph
Nietzsche: Exposing the Christianity Hoax      For thousands of years the Bible has represented the foundation for one of the largest religions in existence, Christianity. â€Å"The Book†affects millions of people’s lives. The creation of morals makes the biggest impacts on individuals and society. Morals are hinted at throughout â€Å"The Book†, but are clearly stated in Matthew’s gospel. These morals are written in a series called the Beatitudes. Through morals, laws are created and society is given guidelines, most people see this in a positive manner. Friederich Nietzsche, a philosopher from the late 1800’s, views religion as a cult made for weak minded simpletons who need something to carry them through life. Nietzsche is often viewed as an antichrist; in fact he even wrote â€Å"The Antichrist,†an essay that seems to be his boarding pass and a ticket to hell. But there is some merit in his satanic ideas about religion one need only to view them from faithless e yes. Nietzsche’s ideas dismiss those of Matthew and how religion is a con to suppress the strong and make the weak feel important.      Nietzsche sees religious people as weak people who hate the strong and independent. In essay one he calls all priests â€Å"the great haters of history†¦likewise the most ingenious haters. (p. 33)†They are not able to go out into the world and naturally live without supernatural excuses and reasons for both their failures and successes. They cannot account for their own actions. In order to stop their feelings of weakness they must convince others that they are right and to follow them, giving them acceptance to in group. (p. 34) Through convincing sermons Christianity began to grow.      This con of the weak people can be traced back to two words - good and bad. Before Christianity good and bad represented social status (p. 25) Nietzsche claims that the concept of good was originally a synonym for nobility. At the same time anyone who was poor or simple was referred to as bad. The words had no moral value and were not part of some â€Å"higher†judgment. It was priests that transformed these words so that good refers to the poor and lower class members of society, and the privileged are now seen as evil. This reversal of good and bad is seen in the Beatitudes. It is not the rich and powerful who are favored by God but the weak and poor.      In Nietzsche’s mind nothing ... ...s are created. Unlike the weak and poor priest who must give sermons and use persuasion to gather followers, the â€Å"Super Man†unknowingly attracts followers through behavior and could care less if he is accepted by, let alone leading, a group.      Matthew’s gospel is a morally sound guideline to being the perfect Christian. Be kind to your neighbors. Help the poor. Be meek and poor for you will inherit the earth. Nietzsche would spit on these â€Å"virtues.†He believes that the gospel is the word of the weak and unwanted. The meek will only make a difference if they band together and start a resentiment, which is when the meek revolt and turn against the â€Å"noble†or strong. This is the only way that the poor can gain any power in society. In Nietzsche’s eyes religion was the ultimate con on the human race. A few weak men’s ideas spawned a worldwide movement to suppress the strong and noble. This movement will hinder the innate instinct to gain power and be the strongest util man realizes he controls his fate and religion is a fantasy.                                                                                                                                                      Â
Saturday, January 11, 2020
African-Americans Fighting for Equality Essay
African-Americans have been fighting for equality and freedom every since they were taken from Africa as slaves. They were stolen from their families and separated only to be servants to others as they were belittled, beaten, put down and treated as nothing. Many things have changed over the centuries, but African-Americans still fight everyday for different types of acknowledgements and equality. They have fought hard over the centuries to end segregation, discrimination, and isolation to attain equality and civil rights. Through the Civil Rights Movement African Americans played important roles American history with courage, strength, and struggling to live equal in America. We have learned about important people and events throughout history, but the fight against discrimination, segregation and isolation have not always been focused on. This paper will highlight how some of the well known and unknown people contributed towards the Civil Rights Movement, in which continues to be fought in present time. â€Å"Racial segregation was a system derived from the efforts of white Americans to keep African Americans in a subordinate status by denying them equal access to public facilities and ensuring that blacks lived apart from whites†(Lawson, 2009). Slaves lived in quarters far away from the master houses on the plantations, the only ones that lived in the house were the special chosen. â€Å"By the time the Supreme Court ruled in Dred Scott v. Sanford (1857) that African Americans were not U. S. citizens, northern whites had excluded blacks from seats on public transportation and barred their entry, except as servants, from most hotels and restaurants. When allowed into auditoriums and theaters, blacks occupied separate sections; they also attended segregated schools. Most churches, too, were segregated. †(Lawson, 2009). Rosa Parks was famous for her courage to stand for her right to sit where ever she wanted on a bus, but she was not the first or only one to make this choice. There was a fifteen year old girl that was arrested nine months earlier, but she was not attributed to the act because of her status of being a foul mouth tomboy and getting pregnant right after the incident (Young, 2000). Also when Rosa Parks was approached by the bus driver to move there were other African- American people sitting next to her, but because she spoke up first history gives her credit and was noticed by Dr. Martin Luther King. It needs to be known that many people were courageous in their act to fight for equal rights. Basically Parks was at the right place at the right time, â€Å"Parks arrest sparked a chain reaction that started the bus boycott that launched the civil rights movement that transformed the apartheid of America’s southern states from a local idiosyncrasy to an international scandal. It was her individual courage that triggered the collective display of defiance that turned a previously unknown 26-year-old preacher, Martin Luther King, into a household name†(Younge, 2000). Dr. Martin Luther King name goes down in history as the most well known activists through the years. He was known as a non violent activist, in which he adapted the philosophy from Gandhi, which was respected not only by the black race but also by all other races. King’s speech â€Å"I Have a Dream†became what African-American’s live by for centuries to come. Also there was the, â€Å"We Shall Overcome†speech on August 23, 1963. King’s words at the capital that day were a defining moment of the Civil Rights movement†(Bowles, 2011). King fought for civil rights until the day he was killed. There was a protest at Fisk University in Nashville in which three students was disgusted at the fact blacks could not sit at the lunch counters to eat. C. T. Vivian, Diane Nash and Bernard Lafayette protested with others in Nashville on April 19, 1960. â€Å"Nash confronted Mayor Ben West. In what she calls a â€Å"divine inspiration,†she asked the mayor to end racial segregation. He appealed to all not to discriminate. She asked him if he meant that to include lunch counters. He sidestepped. She said, â€Å"Mayor, do you recommend that the lunch counters be desegregated? †West said, â€Å"Yes,†and the battle was won. Within days, integration began†(Weier, 2001). While civil rights activists were fighting on the home front, African American men and women honorably performed their duties in two world wars. They bravely entered a military that was at odds about their presence and the appropriate roles for blacks. While more than 400,000 African American soldiers were going through basic training, receiving their assignments or facing the enemy’s bullets in World War I, riots against black citizens were escalating in the United States. By the time the Second World War ended, over one million black forces returned home to the U. S. equivalent of apartheid. Yet, with the knowledge of conditions at home, black soldiers still distinguished themselves in battles for freedoms, which they were unable to enjoy (Blakely, 1999). Discrimination was popular in the 1900’s and African-Americans stood up to be treated as equal Americans as the whites, especially in the World War II. â€Å"While willing to fight for their country, some also made a stand against discrimination while they served. For example, on April 12, 1945, the U. S. Army took 101 African American officers into custody because they directly refused an order from a superior officer. This was a serious charge because, if convicted, they would face the death penalty†(Bowles, 2011). They wanted to get acknowledged for their bravery and accomplishments in the war just the white soldiers. America waited decades for the African –American soldiers of the World War II to get the proper acknowledgements they deserve, which was too little too late. â€Å"These men were willing to die for the country; they were not eligible for many of the honors for their service. Though many deserved it, no African American could receive the Medal of Honor, the highest military award for bravery. Bill Clinton corrected this error 50 years later, bestowing the medal on seven men, but just one, Vernon Baker, was still alive (Bowles, 2011). These men were known as the Tuskegee Airmen and most of them died before receiving their honors. There were numerous movements and people, even African-American women whom had a hand in battling for equality. They had to fight not only for equality from racism, but also dealing with being judged by their gender. â€Å"The Women’s Service Section (WSS) investigated federally controlled railroad stations and yards at the end of World War I. Few women worked in car cleaning before the war, and railroad management preferred to block women workers, especially African Americans, from gaining any kind of foothold in railroad work. African American women were the single largest group of railroad car cleaners during this period but they were routinely denied adequate facilities, including toilets, locker rooms, and dining facilities throughout the railroad system. By raising the issues of facilities, workers’ rights, and public health, these women shaped federal policy and widened the agenda of the WSS to include a direct attack on segregated workplaces†Muhammad, (2011). Black women wanted to have the same rights as others for going to school with safety and security. â€Å"In Brown v Board of Education (1954) the Supreme Court reversed its ruling in Plessy v. Ferguson. They held that school segregation was inherently unconstitutional because it violated the equal protection clause of the 14th Amendment. This case marked the end of legal segregation in the US†. There were other significant African-American movements that changed history. â€Å"Starting in the 1960s, blacks in Akron began to push for an end to discrimination using various tactics, such as political action, workshops, and employment drives. Opie Evans edited the Akronite and began pushing for changes in his magazine. Protests widened to include sit-ins and other demonstrations†(McClain, 1996). African-Americans such as Martin Luther King Jr . and Malcolm X have become icons of the 1950’s and 1960’s, but the organizational skills and grassroots activism of women such as Ella Baker , Septima Clark , Rosa Parks and Fannie Lou Hamer propelled the movement forward to many successes and inspired a new generation of activists. African-Americans have come a long way fighting for equality and freedom every since the slavery time. They won their freedom and more equality than the ever had along with ending segregation. Many things have changed over the centuries, but African-Americans still fight everyday for different types of acknowledgements. They have fought hard to end segregation, most of discrimination, and isolation to attain equality and civil rights. References Blakely, Gloria. (1999). The 20th Century in CP Time: 1900-1949  We are a People. Sentinel,p. A8. Retrieved July 16, 2012, from ProQuest Newsstand. (Document ID: 490544881). http://proquest. umi. com/pqdweb? did=490544881&sid=2&Fmt=3&clientId=74379&RQT=309&VName=PQD Bowles, M. D. (2011). American History 1865- Present, End of Isolation, San Diego, CA: Bridgepoint Education, Inc. Retrieved on June 11, 2012 from https://content. ashford. edu/books/AUHIS204. 11. 2/sections/sec3. 7 Lawson, S. F. (2009). â€Å"Segregation. †Freedom’s Story, TeacherServe. National Humanities Center. Retrieved on July 16, 2012 from http://nationalhumanitiescenter. org/tserve/freedom/1865-1917/essays/segregation. htm | | Mcclain, S. R. , (1996). The Contributions of Blacks in Akron: 1825-1895, A Doctoral Dissertation, Retrieved on july 17, 2012 from http://www. ci. akron. oh. us/blackhist/timeline/index. htm Muhammad, R. (2011). SEPARATE AND UNSANITARY: African American Women Railroad Car Cleaners and the Women’s Service Section, 1918-1920. Journal of Women’s History, 23(2), 87-111,230. Retrieved July 16, 2012, from Research Library. (Document ID: 2377762701). http://proquest. umi. com/pqdweb? did=2377762701&sid=3&Fmt=3&clientId=74379&RQT=309&VName=PQD Weier, A. (2001). She Socked Segregation Civil Rights Leaders Still Inspires Students, Madison Capital Times. Madison, WI, Retrieved July 27, 2012 from ProQuest. http://search. proquest. com/docview/395202519? accountid=32521 Younge, G. (2000). She Would Not Be Moved. The Guardian. London, UK. , Retrieved July 28, 2012 from ProQuest. http://search. proquest. com/docview/245609939? accountid=32521.
Friday, January 3, 2020
Five Years Data Analysis for Taylor Wimpey Free Essay Example, 1500 words
The company s focus is on maintaining the long term to equity ratio within an acceptable range however, trends do not indicate a particular pattern which can reflect upon the particular policy adopted by the firm to have a pre-determined ratio to follow. It seems that that the firm has a determined policy of adjusting its financing mix according to the economic conditions of the country. During 2009, the firm has been able to consolidate its debt and as such it has further rationalized its cash flows to release some pressure on its depleting resources. Most of the long term debt is in the form of debentures as well as bank loans whereas Bank loans and bonds are in multi-currency i. e. GBP and Canadian/US Dollars which can create significant risk for the firm in terms of foreign exchange risk. The debentures are issued at various rates and are of various maturities with last tranche of bonds to be expired in year 2019. It is critical to note that that the highest rate offered on bond s is 9.00% p. a. which matured in 2009 whereas rates offered on other tranches of bonds range from 4.98% to 6.8% p. a.We will write a custom essay sample on Five Years Data Analysis for Taylor Wimpey or any topic specifically for you Only $17.96 $11.86/page This step decline in the dividends paid out may also be attributed to the fact that the firm was going through a consolidation phase wherein it engaged itself into the consolidation phase and further consolidated its cash flows and rationalize its debt position.
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