1.
Athlone Power Station
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Athlone Power Station was a coal-fired power station in Athlone, Cape Town, South Africa. The site stopped generating power in 2003 and is in the process of being decommissioned and it was commissioned in 1962 with 6 turbines with a nominal capacity of 180 megawatts, and operated by the City of Cape Town. The station, the Between 1985 and 1994 the station was held on standby, between 1995 and 2003 it was mainly used to generate power in peak demand periods and during power failures of the national grid. In 2003, significant investment was required due to the age of the power station, Athlone was the last coal-fired power station operating in Cape Town, the others, in the city centre and Salt River, were demolished in the 1980s and 1990s. The power station building and two 99m high chimneys are still standing while the city decides on the future of the site, list of power stations in South Africa
2.
Cape Town
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Cape Town is a coastal city in South Africa. It is the second-most populous urban area in South Africa after Johannesburg and it is also the capital and primate city of the Western Cape province. As the seat of the Parliament of South Africa, it is also the capital of the country. It forms part of the City of Cape Town metropolitan municipality, the city is famous for its harbour, for its natural setting in the Cape Floristic Region, and for such well-known landmarks as Table Mountain and Cape Point. As of 2014, it is the 10th most populous city in Africa and it is one of the most multicultural cities in the world, reflecting its role as a major destination for immigrants and expatriates to South Africa. The city was named the World Design Capital for 2014 by the International Council of Societies of Industrial Design, in 2014, Cape Town was named the best place in the world to visit by both the American New York Times and the British Daily Telegraph. Located on the shore of Table Bay, Cape Town was first developed by the Dutch East India Company as a station for Dutch ships sailing to East Africa, India. Jan van Riebeecks arrival on 6 April 1652 established the first permanent European settlement in South Africa, Cape Town quickly outgrew its original purpose as the first European outpost at the Castle of Good Hope, becoming the economic and cultural hub of the Cape Colony. Until the Witwatersrand Gold Rush and the development of Johannesburg, Cape Town was the largest city in South Africa, the earliest known remnants in the region were found at Peers Cave in Fish Hoek and date to between 15,000 and 12,000 years ago. It was later renamed by John II of Portugal as Cape of Good Hope because of the optimism engendered by the opening of a sea route to India. Vasco da Gama recorded a sighting of the Cape of Good Hope in 1497, in the late 16th century, Portuguese, French, Danish, Dutch and English but mainly Portuguese ships regularly stopped over in Table Bay en route to the Indies. They traded tobacco, copper and iron with the Khoikhoi in exchange for fresh meat, the settlement grew slowly during this period, as it was hard to find adequate labour. This labour shortage prompted the authorities to import slaves from Indonesia, many of these became ancestors of the first Cape Coloured communities. Some of these, including grapes, cereals, ground nuts, potatoes, apples and citrus, had an important, the Dutch Republic being transformed in Revolutionary Frances vassal Batavian Republic, Great Britain moved to take control of its colonies. Britain captured Cape Town in 1795, but the Cape was returned to the Dutch by treaty in 1803, British forces occupied the Cape again in 1806 following the Battle of Blaauwberg. In the Anglo-Dutch Treaty of 1814, Cape Town was permanently ceded to Britain and it became the capital of the newly formed Cape Colony, whose territory expanded very substantially through the 1800s. With expansion came calls for independence from Britain, with the Cape attaining its own parliament. Suffrage was established according to the non-racial, but sexist Cape Qualified Franchise, the discovery of diamonds in Griqualand West in 1867, and the Witwatersrand Gold Rush in 1886, prompted a flood of immigrants to South Africa
3.
South Africa
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South Africa, officially the Republic of South Africa, is the southernmost country in Africa. South Africa is the 25th-largest country in the world by land area and it is the southernmost country on the mainland of the Old World or the Eastern Hemisphere. About 80 percent of South Africans are of Sub-Saharan African ancestry, divided among a variety of ethnic groups speaking different Bantu languages, the remaining population consists of Africas largest communities of European, Asian, and multiracial ancestry. South Africa is a multiethnic society encompassing a variety of cultures, languages. Its pluralistic makeup is reflected in the recognition of 11 official languages. The country is one of the few in Africa never to have had a coup détat, however, the vast majority of black South Africans were not enfranchised until 1994. During the 20th century, the black majority sought to recover its rights from the dominant white minority, with this struggle playing a role in the countrys recent history. The National Party imposed apartheid in 1948, institutionalising previous racial segregation, since 1994, all ethnic and linguistic groups have held political representation in the countrys democracy, which comprises a parliamentary republic and nine provinces. South Africa is often referred to as the Rainbow Nation to describe the multicultural diversity. The World Bank classifies South Africa as an economy. Its economy is the second-largest in Africa, and the 34th-largest in the world, in terms of purchasing power parity, South Africa has the seventh-highest per capita income in Africa. However, poverty and inequality remain widespread, with about a quarter of the population unemployed, nevertheless, South Africa has been identified as a middle power in international affairs, and maintains significant regional influence. The name South Africa is derived from the geographic location at the southern tip of Africa. Upon formation the country was named the Union of South Africa in English, since 1961 the long form name in English has been the Republic of South Africa. In Dutch the country was named Republiek van Zuid-Afrika, replaced in 1983 by the Afrikaans Republiek van Suid-Afrika, since 1994 the Republic has had an official name in each of its 11 official languages. Mzansi, derived from the Xhosa noun umzantsi meaning south, is a name for South Africa. South Africa contains some of the oldest archaeological and human fossil sites in the world, extensive fossil remains have been recovered from a series of caves in Gauteng Province. The area is a UNESCO World Heritage site and has termed the Cradle of Humankind
4.
Slovakia
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Slovakia, officially the Slovak Republic, is a landlocked country in Central Europe. It is bordered by the Czech Republic and Austria to the west, Poland to the north, Ukraine to the east, Slovakias territory spans about 49,000 square kilometres and is mostly mountainous. The population is over 5 million and comprises mostly ethnic Slovaks, the capital and largest city is Bratislava. The Slavs arrived in the territory of present-day Slovakia in the 5th and 6th centuries, in the 7th century, they played a significant role in the creation of Samos Empire and in the 9th century established the Principality of Nitra. In the 10th century, the territory was integrated into the Kingdom of Hungary, which became part of the Habsburg Empire. After World War I and the dissolution of the Austro-Hungarian Empire, a separate Slovak Republic existed in World War II as a client state of Nazi Germany. In 1945, Czechoslovakia was reëstablished under Communist rule as a Soviet satellite, in 1989 the Velvet Revolution ended authoritarian Communist rule in Czechoslovakia. Slovakia became an independent state on 1 January 1993 after the dissolution of Czechoslovakia. The country maintains a combination of economy with universal health care. The country joined the European Union in 2004 and the Eurozone on 1 January 2009, Slovakia is also a member of the Schengen Area, NATO, the United Nations, the OECD, the WTO, CERN, the OSCE, the Council of Europe and the Visegrád Group. The Slovak economy is one of the fastest growing economies in Europe and its legal tender, the Euro, is the worlds 2nd most traded currency. Although regional income inequality is high, 90% of citizens own their homes, in 2016, Slovak citizens had visa-free or visa-on-arrival access to 165 countries and territories, ranking the Slovak passport 11th in the world. Slovakia is the world’s biggest per-capita car producer with a total of 1,040,000 cars manufactured in the country in 2016 alone, the car industry represents 43 percent of Slovakia’s industrial output, and a quarter of its exports. Radiocarbon datingputs the oldest surviving archaeological artefacts from Slovakia – found near Nové Mesto nad Váhom – at 270,000 BC and these ancient tools, made by the Clactonian technique, bear witness to the ancient habitation of Slovakia. Other stone tools from the Middle Paleolithic era come from the Prévôt cave near Bojnice, the most important discovery from that era is a Neanderthal cranium, discovered near Gánovce, a village in northern Slovakia. The most well-known finds include the oldest female statue made of mammoth-bone, the statue was found in the 1940s in Moravany nad Váhom near Piešťany. Numerous necklaces made of shells from Cypraca thermophile gastropods of the Tertiary period have come from the sites of Zákovská, Podkovice, Hubina and these findings provide the most ancient evidence of commercial exchanges carried out between the Mediterranean and Central Europe. The Bronze Age in the territory of modern-day Slovakia went through three stages of development, stretching from 2000 to 800 BC
5.
Glen Canyon Dam
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Glen Canyon Dam is a concrete arch-gravity dam on the Colorado River in northern Arizona, United States, near the town of Page. The 710-foot high dam was built by the U. S. Bureau of Reclamation from 1956 to 1966 and forms Lake Powell, a dam in Glen Canyon was studied as early as 1924, but these plans were initially dropped in favor of a dam in Black Canyon. After a long fight, the USBR agreed not to build the dam in Dinosaur, since first filling to capacity in 1980, Lake Powell water levels have fluctuated greatly depending on water demand and annual runoff. Operation of Glen Canyon Dam helps ensure a distribution of water between the states of the Upper Colorado River Basin and the Lower Basin. During years of drought, Glen Canyon guarantees a water delivery to the Lower Basin states, in wet years, it captures extra runoff for future use. The dam is also a source of hydroelectricity, averaging over 4 billion kilowatt hours per year. Water managers and utilities state that the dam is a source of renewable energy. Annual discharge from the Colorado River and its tributaries ranges from 4 to 22 million acre feet, flooding, and the rivers enormous silt or sediment load, created problems for settlements in the Lower Colorado River Valley and navigation on the lower portion of the river. During droughts, there was too little water available for irrigation, in 1904, the Colorado River was accidentally redirected after it damaged a canal gate in Mexico, causing the river to flood part of Californias Imperial Valley and create the Salton Sea. After this catastrophe, California and Arizona began to call for a dam to control the tempestuous river, in 1922, six U. S. states signed the Colorado River Compact to officially allocate the flow of the Colorado River and its tributaries. The third lower basin state, Arizona, did not ratify the Compact until 1944 because it was concerned that California might seek to appropriate a portion of its share before it could be put to use. The total,16.5 million acre feet, was based on thirty years of streamflow records starting in the late 1890s. It was believed to represent the flow as measured at Lees Ferry. As it turned out, the early 20th century was one of the wettest periods in the last 800 years, the dependable natural flow past Lees Ferry is now believed to be about 13.5 to 14.6 million acre feet. These studies found that the lower Colorado sites had stronger foundation rock which might result in less reservoir seepage, the Glen Canyon site, furthermore, was so remote that delivering supplies and transporting workers there would be infeasible at the time. However, what killed the first Glen Canyon proposal was the fact that it lies upstream of the Lees Ferry dividing line. With its substantial Congressional clout, California refused to allow the virtual faucets of a Colorado River dam to be built in what amounted to hostile territory. However, it was not able to weather the worst floods or droughts, but most importantly, Hoover only controlled the lower portion of the river
6.
Page, Arizona
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Page is a city in Coconino County, Arizona, United States, near the Glen Canyon Dam and Lake Powell. As of the 2010 census, the population of the city was 7,247, unlike other cities in the area, Page was founded in 1957 as a housing community for workers and their families during the construction of nearby Glen Canyon Dam on the Colorado River. Its 17-square-mile site was obtained in an exchange with the Navajo Nation. The city is perched atop Manson Mesa at an elevation of 4,300 feet above sea level and 600 feet above Lake Powell, the city was originally called Government Camp, but was later named for John C. Page, Commissioner of the Bureau of Reclamation, 1936-1943, after the dam was completed in the 1960s, the city grew steadily to todays population of over 7,000. Page is also the home of two of the largest electrical generation units in the western United States, Glen Canyon Dam has a 1,288, 000-kilowatt capacity when fully online. The other power plant to the southeast is the Navajo Generating Station, Page is located at 36°54′51″N 111°27′35″W. According to the United States Census Bureau, the city has an area of 16.6 square miles, of which 16.6 square miles is land and 0.04 square miles. Page has a climate with hot, very dry summers. It is located in the edge of the Great Basin Desert on the Colorado Plateau. It is very dry due to being in the rainshadow of the mountains of California, as of the census of 2000, there were 6,809 people,2,342 households, and 1,779 families residing in the city. The population density was 410.5 inhabitants per square mile, there were 2,606 housing units at an average density of 157.1 per square mile. The racial makeup of the city was 67. 32% White,0. 40% Black or African American,26. 69% Native American,0. 68% Asian,0. 19% Pacific Islander,1. 62% from other races, and 3. 11% from two or more races. 4. 70% of the population were Hispanic or Latino of any race,19. 0% of all households were made up of individuals and 5. 1% had someone living alone who was 65 years of age or older. The average household size was 2.90 and the family size was 3.33. In the city, the age distribution of the population shows 32. 0% under the age of 18,9. 5% from 18 to 24,27. 5% from 25 to 44,24. 7% from 45 to 64, the median age was 32 years. For every 100 females there were 100.9 males, for every 100 females age 18 and over, there were 98.4 males. The median income for a household in the city was $46,935, males had a median income of $42,040 versus $24,744 for females
7.
Electricity generation
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Electricity generation is the process of generating electric power from sources of primary energy. For electric utilities, it is the first process in the delivery of electricity to consumers, the other processes as transmission, distribution, energy storage and recovery using pumped-storage methods are normally carried out by the electric power industry. Other energy sources include solar photovoltaics and geothermal power, the fundamental principles of electricity generation were discovered during the 1820s and early 1830s by the British scientist Michael Faraday. This method is used today, electricity is generated by the movement of a loop of wire. Central power stations became practical with the development of alternating current power transmission, using power transformers to transmit power at high voltage. Electricity has been generated at central stations since 1882, the use of power-lines and power-poles have been significantly important in the distribution of electricity. There are seven fundamental methods of transforming other forms of energy into electrical energy. Static electricity, form the physical separation and transport of charge and it was the first form discovered and investigated, and the electrostatic generator is still used even in modern devices such as the Van de Graaff generator and MHD generators. In Electromagnetic induction, a generator, dynamo or alternator transforms kinetic energy into electricity. This is the most used form for generating electricity and is based on Faradays law and it can be experimented by rotating a magnet within closed loops of a conducting material. Almost all commercial electrical generation is done using electromagnetic induction, in mechanical energy forces a generator to rotate. Almost all electrical power on Earth is generated with a turbine, driven by wind, water, there are many different methods of developing mechanical energy, including heat engines, hydro, wind and tidal power. Most electric generation is driven by heat engines, the combustion of fossil fuels supplies most of the heat to these engines, with a significant fraction from nuclear fission and some from renewable sources. The modern steam turbine currently generates about 80% of the power in the world using a variety of heat sources. Power sources include, Steam Water is boiled by coal burned in a power plant. Nuclear fission heat created in a nuclear reactor creates steam, less than 15% of electricity is generated this way. Natural gas, turbines are directly by gases produced by combustion. Combined cycle are driven by steam and natural gas
8.
Electric power
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Electric power is the rate, per unit time, at which electrical energy is transferred by an electric circuit. The SI unit of power is the watt, one joule per second, Electric power is usually produced by electric generators, but can also be supplied by sources such as electric batteries. It is usually supplied to businesses and homes by the power industry through an electric power grid. Electric power is sold by the kilowatt hour which is the product of power in kilowatts multiplied by running time in hours. Electric utilities measure power using an electricity meter, which keeps a total of the electric energy delivered to a customer. Electrical power provides a low form of energy and can be carried long distances and converted into other forms of energy such as motion. Electric power, like power, is the rate of doing work, measured in watts. The term wattage is used colloquially to mean electric power in watts, the potential energy of the charges due to the voltage between the terminals is converted to kinetic energy in the device. These devices are called passive components or loads, they consume electric power from the circuit, converting it to other forms of such as mechanical work, heat, light. Examples are electrical appliances, such as bulbs, electric motors. In alternating current circuits the direction of the voltage periodically reverses, devices in which this occurs are called active devices or power sources, such as electric generators and batteries. Some devices can be either a source or a load, depending on the voltage, for example, a rechargeable battery acts as a source when it provides power to a circuit, but as a load when it is connected to a battery charger and is being recharged. Since electric power can flow either into or out of a component, Electric power flowing out of a circuit into a component is arbitrarily defined to have a positive sign, while power flowing into a circuit from a component is defined to have a negative sign. Thus passive components have positive power consumption, while power sources have negative power consumption and this is called the passive sign convention. In alternating current circuits, energy storage such as inductance and capacitance may result in periodic reversals of the direction of energy flow. The portion of power flow that, averaged over a cycle of the AC waveform. That portion of power due to stored energy, that returns to the source in each cycle, is known as reactive power. Real power is represented as a vector and reactive power is represented as a vertical vector
9.
Electric generator
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In electricity generation, a generator is a device that converts mechanical energy to electrical energy for use in an external circuit. Sources of mechanical energy include steam turbines, gas turbines, water turbines, internal combustion engines, the first electromagnetic generator, the Faraday disk, was built in 1831 by British scientist Michael Faraday. Generators provide nearly all of the power for electric power grids, the reverse conversion of electrical energy into mechanical energy is done by an electric motor, and motors and generators have many similarities. Many motors can be driven to generate electricity and frequently make acceptable manual generators. Electromagnetic generators fall into one of two categories, dynamos and alternators. The magnetic field of the dynamo or alternator can be provided by either wire windings called field coils or permanent magnets, a generator using permanent magnets is sometimes called a magneto. Armature, The power-producing component of an electrical machine, in a generator, alternator, or dynamo the armature windings generate the electric current, which provides power to an external circuit. The armature can be on either the rotor or the stator, depending on the design, before the connection between magnetism and electricity was discovered, electrostatic generators were invented. They operated on electrostatic principles, by using moving electrically charged belts, plates, the charge was generated using either of two mechanisms, electrostatic induction or the triboelectric effect. Such generators generated very high voltage and low current and their only practical applications were to power early X-ray tubes, and later in some atomic particle accelerators. The operating principle of electromagnetic generators was discovered in the years of 1831–1832 by Michael Faraday, the principle later called Faradays law, is that an electromotive force is generated in an electrical conductor which encircles a varying magnetic flux. He also built the first electromagnetic generator, called the Faraday disk and it produced a small DC voltage. This design was inefficient, due to self-cancelling counterflows of current in regions of the disk that were not under the influence of the magnetic field. While current was induced directly underneath the magnet, the current would circulate backwards in regions that were outside the influence of the magnetic field and this counterflow limited the power output to the pickup wires, and induced waste heating of the copper disc. Later homopolar generators would solve this problem by using an array of magnets arranged around the perimeter to maintain a steady field effect in one current-flow direction. Another disadvantage was that the voltage was very low, due to the single current path through the magnetic flux. Experimenters found that using multiple turns of wire in a coil could produce higher, since the output voltage is proportional to the number of turns, generators could be easily designed to produce any desired voltage by varying the number of turns. Wire windings became a feature of all subsequent generator designs
10.
Relative velocity
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The relative velocity v → B | A is the velocity of an object or observer B in the rest frame of another object or observer A. We begin with relative motion in the classical, that all speeds are less than the speed of light. This limit is associated with the Galilean transformation, the figure shows a man on top of a train, at the back edge. At 1,00 pm he begins to forward at a walking speed of 10 km/hr. The train is moving at 40 km/hr, the figure depicts the man and train at two different times, first, when the journey began, and also one hour later at 2,00 pm. The figure suggests that the man is 50 km from the point after having traveled for one hour. This, by definition, is 50 km/hour, which suggests that the prescription for calculating relative velocity in this fashion is to add the two velocities. The figure displays clocks and rulers to remind the reader that while the logic behind this calculation seem flawless, it makes false assumptions about how clocks, V → M | T is the velocity of the Man relative to the Train. V → T | E is the velocity of the Train relative to Earth, fully legitimate expressions for the velocity of A relative to B include the velocity of A with respect to B and the velocity of A in the coordinate system where B is always at rest. The violation of special relativity occurs because this equation for relative velocity falsely predicts that different observers will measure different speeds when observing the motion of light, the figure shows two objects moving at constant velocity. The equations of motion are, r → A = r → A i + v → A t r → B = r → B i + v → B t, where the subscript i refers to the initial displacement. The difference between the two displacement vectors, r → B − r → A, represents the location of B as seen from A, to construct a theory of relative motion consistent with the theory of special relativity, we must adopt a different convention. Recall that v is the motion of an object in the primed frame. As in classical mechanics, in Special Relativity the relative velocity v → B | A is the velocity of an object or observer B in the rest frame of object or observer A. This rotation has no effect on the magnitude of a vector, beer and Johnston, Statics and Dynamics. McGraw Hill Dictionary of Physics and Mathematics, Mechanics, Engineering Mechanics, Statics, Dynamics Relative Motion at HyperPhysics A Java applet illustrating Relative Velocity, by Andrew Duffy Relatív mozgás. Sebességek összegzése Relative tranquility of trout in creek
11.
Magnetic field
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A magnetic field is the magnetic effect of electric currents and magnetic materials. The magnetic field at any point is specified by both a direction and a magnitude, as such it is represented by a vector field. The term is used for two distinct but closely related fields denoted by the symbols B and H, where H is measured in units of amperes per meter in the SI, B is measured in teslas and newtons per meter per ampere in the SI. B is most commonly defined in terms of the Lorentz force it exerts on moving electric charges, Magnetic fields can be produced by moving electric charges and the intrinsic magnetic moments of elementary particles associated with a fundamental quantum property, their spin. In quantum physics, the field is quantized and electromagnetic interactions result from the exchange of photons. Magnetic fields are used throughout modern technology, particularly in electrical engineering. The Earth produces its own field, which is important in navigation. Rotating magnetic fields are used in electric motors and generators. Magnetic forces give information about the carriers in a material through the Hall effect. The interaction of magnetic fields in electric devices such as transformers is studied in the discipline of magnetic circuits, noting that the resulting field lines crossed at two points he named those points poles in analogy to Earths poles. He also clearly articulated the principle that magnets always have both a north and south pole, no matter how finely one slices them, almost three centuries later, William Gilbert of Colchester replicated Petrus Peregrinus work and was the first to state explicitly that Earth is a magnet. Published in 1600, Gilberts work, De Magnete, helped to establish magnetism as a science, in 1750, John Michell stated that magnetic poles attract and repel in accordance with an inverse square law. Charles-Augustin de Coulomb experimentally verified this in 1785 and stated explicitly that the north and south poles cannot be separated, building on this force between poles, Siméon Denis Poisson created the first successful model of the magnetic field, which he presented in 1824. In this model, a magnetic H-field is produced by magnetic poles, three discoveries challenged this foundation of magnetism, though. First, in 1819, Hans Christian Ørsted discovered that an electric current generates a magnetic field encircling it, then in 1820, André-Marie Ampère showed that parallel wires having currents in the same direction attract one another. Finally, Jean-Baptiste Biot and Félix Savart discovered the Biot–Savart law in 1820, extending these experiments, Ampère published his own successful model of magnetism in 1825. This has the benefit of explaining why magnetic charge can not be isolated. Also in this work, Ampère introduced the term electrodynamics to describe the relationship between electricity and magnetism, in 1831, Michael Faraday discovered electromagnetic induction when he found that a changing magnetic field generates an encircling electric field
12.
Electrical conductor
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In physics and electrical engineering, a conductor is an object or type of material that allows the flow of an electrical current in one or more directions. Materials made of metal are common electrical conductors, Electrical current is generated by the flow of negatively charged electrons, positively charged holes, and positive or negative ions in some cases. In order for current to flow, it is not necessary for one charged particle to travel from the producing the current to that consuming it. Instead, the particle simply needs to nudge its neighbor a finite amount who will nudge its neighbor and on and on until a particle is nudged into the consumer. Essentially what is occurring here is a chain of momentum transfer between mobile charge carriers, the Drude model of conduction describes this process more rigorously. Insulators are non-conducting materials with few mobile charges that support only insignificant electric currents, the resistance of a given conductor depends on the material it is made of, and on its dimensions. For a given material, the resistance is proportional to the cross-sectional area. For example, a copper wire has lower resistance than an otherwise-identical thin copper wire. Also, for a material, the resistance is proportional to the length, for example. The resistance R and conductance G of a conductor of uniform cross section, therefore, the resistivity and conductivity are proportionality constants, and therefore depend only on the material the wire is made of, not the geometry of the wire. Resistivity and conductivity are reciprocals, ρ =1 / σ, resistivity is a measure of the materials ability to oppose electric current. This formula is not exact, It assumes the current density is uniform in the conductor. However, this still provides a good approximation for long thin conductors such as wires. Another situation this formula is not exact for is with alternating current, then, the geometrical cross-section is different from the effective cross-section in which current actually flows, so the resistance is higher than expected. Similarly, if two conductors are each other carrying AC current, their resistances increase due to the proximity effect. Aside from the geometry of the wire, temperature also has a significant effect on the efficacy of conductors, temperature affects conductors in two main ways, the first is that materials may expand under the application of heat. The amount that the material will expand is governed by the expansion coefficient specific to the material. Such an expansion will change the geometry of the conductor and therefore its characteristic resistance, however, this effect is generally small, on the order of 10−6
13.
Electric current
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An electric current is a flow of electric charge. In electric circuits this charge is carried by moving electrons in a wire. It can also be carried by ions in an electrolyte, or by both ions and electrons such as in an ionised gas. The SI unit for measuring a current is the ampere. Electric current is measured using a device called an ammeter, electric currents cause Joule heating, which creates light in incandescent light bulbs. They also create magnetic fields, which are used in motors, inductors and generators, the particles that carry the charge in an electric current are called charge carriers. In metals, one or more electrons from each atom are loosely bound to the atom and these conduction electrons are the charge carriers in metal conductors. The conventional symbol for current is I, which originates from the French phrase intensité de courant, current intensity is often referred to simply as current. The I symbol was used by André-Marie Ampère, after whom the unit of current is named, in formulating the eponymous Ampères force law. The notation travelled from France to Great Britain, where it became standard, in a conductive material, the moving charged particles which constitute the electric current are called charge carriers. In other materials, notably the semiconductors, the carriers can be positive or negative. Positive and negative charge carriers may even be present at the same time, a flow of positive charges gives the same electric current, and has the same effect in a circuit, as an equal flow of negative charges in the opposite direction. Since current can be the flow of positive or negative charges. The direction of current is arbitrarily defined as the same direction as positive charges flow. This is called the direction of current I. If the current flows in the direction, the variable I has a negative value. When analyzing electrical circuits, the direction of current through a specific circuit element is usually unknown. Consequently, the directions of currents are often assigned arbitrarily
14.
Fossil fuel
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Fossil fuels are fuels formed by natural processes such as anaerobic decomposition of buried dead organisms, containing energy originating in ancient photosynthesis. The age of the organisms and their resulting fossil fuels is typically millions of years, Fossil fuels contain high percentages of carbon and include petroleum, coal, and natural gas. Other commonly used derivatives include kerosene and propane, Fossil fuels range from volatile materials with low carbon, hydrogen ratios like methane, to liquids like petroleum, to nonvolatile materials composed of almost pure carbon, like anthracite coal. Methane can be found in hydrocarbon fields either alone, associated with oil, non-fossil sources in 2006 included nuclear 8. 5%, hydroelectric 6. 3%, and others amounting to 0. 9%. World energy consumption was growing about 2. 3% per year, the use of fossil fuels raises serious environmental concerns. The burning of fossil fuels produces around 21.3 billion tonnes of carbon dioxide per year and it is estimated that natural processes can only absorb about half of that amount, so there is a net increase of 10.65 billion tonnes of atmospheric carbon dioxide per year. Carbon dioxide is a gas that increases radiative forcing and contributes to global warming. A global movement towards the generation of energy is underway to help reduce global greenhouse gas emissions. Over geological time, this matter, mixed with mud. Despite these heat driven transformations, the energy is still photosynthetic in origin. There is a range of organic, or hydrocarbon, compounds in any given fuel mixture. The specific mixture of hydrocarbons gives a fuel its characteristic properties, such as boiling point, melting point, density, viscosity, some fuels like natural gas, for instance, contain only very low boiling, gaseous components. Others such as gasoline or diesel contain much higher boiling components, terrestrial plants, on the other hand, tend to form coal and methane. Many of the coal fields date to the Carboniferous period of Earths history, terrestrial plants also form type III kerogen, a source of natural gas. Fossil fuels are of importance because they can be burned. The use of coal as a fuel predates recorded history, coal was used to run furnaces for the melting of metal ore. Semi-solid hydrocarbons from seeps were also burned in ancient times, commercial exploitation of petroleum, largely as a replacement for oils from animal sources, for use in oil lamps began in the 19th century. Natural gas, once flared-off as an byproduct of petroleum production, is now considered a very valuable resource
15.
Coal
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Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure. Coal is composed primarily of carbon, along with quantities of other elements, chiefly hydrogen, sulfur, oxygen. A fossil fuel, coal forms when plant matter is converted into peat, which in turn is converted into lignite, then sub-bituminous coal, after that bituminous coal. This involves biological and geological processes that take place over time, throughout history, coal has been used as an energy resource, primarily burned for the production of electricity and heat, and is also used for industrial purposes, such as refining metals. Coal is the largest source of energy for the generation of electricity worldwide, the extraction of coal, its use in energy production and its byproducts are all associated with environmental and health effects including climate change. Coal is extracted from the ground by coal mining, since 1983, the worlds top coal producer has been China. In 2015 China produced 3,747 million tonnes of coal –47. 7% of 7,861 million tonnes world coal production, in 2015 other large producers were United States, India, European Union and Australia. The word originally took the col in Old English, from Proto-Germanic *kula. In Old Turkic languages, kül is ash, cinders, öčür is quench, the compound charcoal in Turkic is öčür kül, literally quenched ashes, cinders, coals with elided anlaut ö- and inflection affixes -ülmüş. At various times in the geologic past, the Earth had dense forests in low-lying wetland areas, due to natural processes such as flooding, these forests were buried underneath soil. As more and more soil deposited over them, they were compressed, the temperature also rose as they sank deeper and deeper. As the process continued the plant matter was protected from biodegradation and oxidation and this trapped the carbon in immense peat bogs that were eventually covered and deeply buried by sediments. Under high pressure and high temperature, dead vegetation was slowly converted to coal, as coal contains mainly carbon, the conversion of dead vegetation into coal is called carbonization. The wide, shallow seas of the Carboniferous Period provided ideal conditions for coal formation, the exception is the coal gap in the Permian–Triassic extinction event, where coal is rare. Coal is known from Precambrian strata, which predate land plants — this coal is presumed to have originated from residues of algae, in its dehydrated form, peat is a highly effective absorbent for fuel and oil spills on land and water. It is also used as a conditioner for soil to make it able to retain. Lignite, or brown coal, is the lowest rank of coal, jet, a compact form of lignite, is sometimes polished and has been used as an ornamental stone since the Upper Palaeolithic
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Petroleum
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Petroleum is a naturally occurring, yellow-to-black liquid found in geological formations beneath the Earths surface, which is commonly refined into various types of fuels. Components of petroleum are separated using a technique called fractional distillation and it consists of hydrocarbons of various molecular weights and other organic compounds. The name petroleum covers both naturally occurring unprocessed crude oil and petroleum products that are made up of refined crude oil. A fossil fuel, petroleum is formed when large quantities of dead organisms, usually zooplankton and algae, are buried underneath sedimentary rock, Petroleum has mostly been recovered by oil drilling. Drilling is carried out studies of structural geology, sedimentary basin analysis. Petroleum is used in manufacturing a variety of materials. Concern over the depletion of the earths finite reserves of oil, the burning of fossil fuels plays the major role in the current episode of global warming. The word petroleum comes from Greek, πέτρα for rocks and Greek, the term was found in 10th-century Old English sources. It was used in the treatise De Natura Fossilium, published in 1546 by the German mineralogist Georg Bauer, Petroleum, in one form or another, has been used since ancient times, and is now important across society, including in economy, politics and technology. Great quantities of it were found on the banks of the river Issus, ancient Persian tablets indicate the medicinal and lighting uses of petroleum in the upper levels of their society. By 347 AD, oil was produced from bamboo-drilled wells in China, early British explorers to Myanmar documented a flourishing oil extraction industry based in Yenangyaung that, in 1795, had hundreds of hand-dug wells under production. The mythological origins of the oil fields at Yenangyaung, and its hereditary monopoly control by 24 families, Pechelbronn is said to be the first European site where petroleum has been explored and used. The still active Erdpechquelle, a spring where petroleum appears mixed with water has been used since 1498, Oil sands have been mined since the 18th century. In Wietze in lower Saxony, natural asphalt/bitumen has been explored since the 18th century, both in Pechelbronn as in Wietze, the coal industry dominated the petroleum technologies. In 1848 Young set up a small business refining the crude oil, Young eventually succeeded, by distilling cannel coal at a low heat, in creating a fluid resembling petroleum, which when treated in the same way as the seep oil gave similar products. The production of oils and solid paraffin wax from coal formed the subject of his patent dated 17 October 1850. In 1850 Young & Meldrum and Edward William Binney entered into partnership under the title of E. W. Binney & Co. at Bathgate in West Lothian, the worlds first oil refinery was built in 1856 by Ignacy Łukasiewicz. The demand for petroleum as a fuel for lighting in North America, edwin Drakes 1859 well near Titusville, Pennsylvania, is popularly considered the first modern well
17.
Natural gas
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It is formed when layers of decomposing plant and animal matter are exposed to intense heat and pressure under the surface of the Earth over millions of years. The energy that the plants originally obtained from the sun is stored in the form of bonds in the gas. Natural gas is a fuel used as a source of energy for heating, cooking. It is also used as fuel for vehicles and as a feedstock in the manufacture of plastics. Natural gas is found in underground rock formations or associated with other hydrocarbon reservoirs in coal beds. Petroleum is another resource and fossil fuel found in proximity to. Most natural gas was created over time by two mechanisms, biogenic and thermogenic, biogenic gas is created by methanogenic organisms in marshes, bogs, landfills, and shallow sediments. Deeper in the earth, at temperature and pressure, thermogenic gas is created from buried organic material. In petroleum production gas is burnt as flare gas. The World Bank estimates that over 150 cubic kilometers of gas are flared or vented annually. Before natural gas can be used as a fuel, most, Natural gas is often informally referred to simply as gas, especially when compared to other energy sources such as oil or coal. However, it is not to be confused with gasoline, especially in North America, Natural gas was used by the Chinese in about 500 BCE. They discovered a way to transport gas seeping from the ground in crude pipelines of bamboo to where it was used to salt water to extract the salt. The worlds first industrial extraction of gas started at Fredonia, New York. By 2009,66000 km³ had been used out of the total 850000 km³ of estimated remaining reserves of natural gas. An annual increase in usage of 2–3% could result in currently recoverable reserves lasting significantly less, unwanted natural gas was a disposal problem in the active oil fields. If there was not a market for natural gas near the wellhead it was expensive to pipe to the end user. In the 19th century and early 20th century, unwanted gas was burned off at oil fields
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Nuclear power
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Nuclear power is the use of nuclear reactions that release nuclear energy to generate heat, which most frequently is then used in steam turbines to produce electricity in a nuclear power plant. The term includes nuclear fission, nuclear decay and nuclear fusion, since all electricity supplying technologies use cement, etc. during construction, emissions are yet to be brought to zero. Each result is contrasted with coal and fossil gas at 820 and 490 g CO2 eq/kWh, there is a social debate about nuclear power. Proponents, such as the World Nuclear Association and Environmentalists for Nuclear Energy, contend that nuclear power is a safe, opponents, such as Greenpeace International and NIRS, contend that nuclear power poses many threats to people and the environment. These include the Chernobyl disaster which occurred in 1986, the Fukushima Daiichi nuclear disaster, there have also been some nuclear submarine accidents. Energy production from coal, petroleum, natural gas and hydroelectricity has caused a number of fatalities per unit of energy generated due to air pollution. In 2015, Ten new reactors were connected to the grid, seven reactors were permanently shut down. 441 reactors had a net capacity of 382,855 megawatts of electricity. 67 new nuclear reactors were under construction, Most of the new activity is in China where there is an urgent need to control pollution from coal plants. In October 2016, Watts Bar 2 became the first new United States reactor to enter commercial operation since 1996. The same year, his doctoral student James Chadwick discovered the neutron, further work by Enrico Fermi in the 1930s focused on using slow neutrons to increase the effectiveness of induced radioactivity. Experiments bombarding uranium with neutrons led Fermi to believe he had created a new, transuranic element and they determined that the relatively tiny neutron split the nucleus of the massive uranium atoms into two roughly equal pieces, contradicting Fermi. Numerous scientists, including Leó Szilárd, who was one of the first, recognized that if fission reactions released additional neutrons, a self-sustaining nuclear chain reaction could result. In the United States, where Fermi and Szilárd had both emigrated, this led to the creation of the first man-made reactor, known as Chicago Pile-1, which achieved criticality on December 2,1942. In 1945, the pocketbook The Atomic Age heralded the untapped atomic power in everyday objects and depicted a future where fossil fuels would go unused. One science writer, David Dietz, wrote that instead of filling the gas tank of a car two or three times a week, people travel for a year on a pellet of atomic energy the size of a vitamin pill. The United Kingdom, Canada, and the USSR proceeded over the course of the late 1940s, electricity was generated for the first time by a nuclear reactor on December 20,1951, at the EBR-I experimental station near Arco, Idaho, which initially produced about 100 kW. Work was also researched in the US on nuclear marine propulsion
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Renewable energy
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Renewable energy is energy that is collected from renewable resources, which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat. Renewable energy often provides energy in four important areas, electricity generation, air and water heating/cooling, transportation, based on REN21s 2016 report, renewables contributed 19. 2% to humans global energy consumption and 23. 7% to their generation of electricity in 2014 and 2015, respectively. This energy consumption is divided as 8. 9% coming from biomass,4. 2% as heat energy,3. 9% hydro electricity and 2. 2% is electricity from wind, solar, geothermal. Worldwide investments in renewable technologies amounted to more than US$286 billion in 2015, with countries like China, globally, there are an estimated 7.7 million jobs associated with the renewable energy industries, with solar photovoltaics being the largest renewable employer. As of 2015 worldwide, more than half of all new electricity capacity installed was renewable, Renewable energy resources exist over wide geographical areas, in contrast to other energy sources, which are concentrated in a limited number of countries. Rapid deployment of energy and energy efficiency is resulting in significant energy security, climate change mitigation. In international public opinion there is strong support for promoting renewable sources such as solar power. At the national level, at least 30 nations around the already have renewable energy contributing more than 20 percent of energy supply. National renewable energy markets are projected to continue to grow strongly in the coming decade, for example, in Denmark the government decided to switch the total energy supply to 100% renewable energy by 2050. While many renewable energy projects are large-scale, renewable technologies are also suited to rural and remote areas and developing countries, United Nations Secretary-General Ban Ki-moon has said that renewable energy has the ability to lift the poorest nations to new levels of prosperity. Renewable energy systems are becoming more efficient and cheaper. Their share of energy consumption is increasing. Growth in consumption of coal and oil could end by 2020 due to increased uptake of renewables, in its various forms, it derives directly from the sun, or from heat generated deep within the earth. Included in the definition is electricity and heat generated from solar, wind, ocean, hydropower, biomass, geothermal resources, rapid deployment of renewable energy and energy efficiency, and technological diversification of energy sources, would result in significant energy security and economic benefits. New government spending, regulation and policies helped the industry weather the financial crisis better than many other sectors. As of 2011, small solar PV systems provide electricity to a few million households, United Nations Secretary-General Ban Ki-moon has said that renewable energy has the ability to lift the poorest nations to new levels of prosperity. At the national level, at least 30 nations around the already have renewable energy contributing more than 20% of energy supply. Some countries have much higher long-term policy targets of up to 100% renewables, outside Europe, a diverse group of 20 or more other countries target renewable energy shares in the 2020–2030 time frame that range from 10% to 50%
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Solar power
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Solar power is the conversion of energy from sunlight into electricity, either directly using photovoltaics, or indirectly using concentrated solar power. Concentrated solar power systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam, Photovoltaic cells convert light into an electric current using the photovoltaic effect. Most solar installations would be in China and India, Solar PV is rapidly becoming an inexpensive, low-carbon technology to harness renewable energy from the Sun. The current largest photovoltaic power station in the world is the 850 MW Longyangxia Dam Solar Park, in Qinghai, commercial concentrated solar power plants were first developed in the 1980s. The 392 MW Ivanpah installation is the largest concentrating solar power plant in the world, long distance transmission allows remote renewable energy resources to displace fossil fuel consumption. Solar power plants use one of two technologies, Photovoltaic systems use solar panels, either on rooftops or in ground-mounted solar farms, concentrated solar power plants use solar thermal energy to make steam, that is thereafter converted into electricity by a turbine. A solar cell, or photovoltaic cell, is a device that converts light into electric current using the photovoltaic effect, the first solar cell was constructed by Charles Fritts in the 1880s. The German industrialist Ernst Werner von Siemens was among those who recognized the importance of this discovery, following the work of Russell Ohl in the 1940s, researchers Gerald Pearson, Calvin Fuller and Daryl Chapin created the silicon solar cell in 1954. These early solar cells cost 286 USD/watt and reached efficiencies of 4. 5–6%, the array of a photovoltaic power system, or PV system, produces direct current power which fluctuates with the sunlights intensity. For practical use this usually requires conversion to certain desired voltages or alternating current, multiple solar cells are connected inside modules. Modules are wired together to form arrays, then tied to an inverter, which produces power at the voltage, and for AC. Many residential PV systems are connected to the grid wherever available, in these grid-connected PV systems, use of energy storage is optional. In certain applications such as satellites, lighthouses, or in developing countries, batteries or additional power generators are often added as back-ups, such stand-alone power systems permit operations at night and at other times of limited sunlight. Concentrated solar power, also called concentrated solar thermal, uses lenses or mirrors, contrary to photovoltaics – which converts light directly into electricity – CSP uses the heat of the suns radiation to generate electricity from conventional steam-driven turbines. A wide range of concentrating technologies exists, among the best known are the trough, the compact linear Fresnel reflector, the Stirling dish. Various techniques are used to track the sun and focus light, in all of these systems a working fluid is heated by the concentrated sunlight, and is then used for power generation or energy storage. Thermal storage efficiently allows up to 24-hour electricity generation, a parabolic trough consists of a linear parabolic reflector that concentrates light onto a receiver positioned along the reflectors focal line. The receiver is a tube positioned right above the middle of the mirror and is filled with a working fluid
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Wind power
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Wind power is the use of air flow through wind turbines to mechanically power generators for electric power. The net effects on the environment are far less problematic than those of power sources. Wind farms consist of individual wind turbines which are connected to the electric power transmission network. Onshore wind is a source of electric power, competitive with or in many places cheaper than coal or gas plants. Offshore wind is steadier and stronger than on land, and offshore farms have less visual impact, small onshore wind farms can feed some energy into the grid or provide electric power to isolated off-grid locations. Wind power gives variable power which is consistent from year to year. It is therefore used in conjunction with other power sources to give a reliable supply. As the proportion of power in a region increases, a need to upgrade the grid. In addition, weather forecasting permits the power network to be readied for the predictable variations in production that occur. As of 2015, Denmark generates 40% of its power from wind. In 2014 global wind power capacity expanded 16% to 369,553 MW, yearly wind energy production is also growing rapidly and has reached around 4% of worldwide electric power usage,11. 4% in the EU. Wind power has been used as long as humans have put sails into the wind, for more than two millennia wind-powered machines have ground grain and pumped water. Wind power was available and not confined to the banks of fast-flowing streams, or later. Wind-powered pumps drained the polders of the Netherlands, and in regions such as the American mid-west or the Australian outback, wind pumps provided water for live stock. The first windmill used for the production of power was built in Scotland in July 1887 by Prof James Blyth of Andersons College. Blyth offered the surplus power to the people of Marykirk for lighting the main street, however. The Brush wind turbine had a rotor 17 metres in diameter and was mounted on an 18 metres tower, although large by todays standards, the machine was only rated at 12 kW. The connected dynamo was used either to charge a bank of batteries or to operate up to 100 incandescent light bulbs, with the development of electric power, wind power found new applications in lighting buildings remote from centrally-generated power
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Wave power
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Wave power is the transport of energy by wind waves, and the capture of that energy to do useful work – for example, electricity generation, water desalination, or the pumping of water. A machine able to exploit wave power is known as a wave energy converter. Wave power is distinct from the flux of tidal power. Wave-power generation is not currently a widely employed commercial technology, although there have been attempts to use it since at least 1890, in 2008, the first experimental wave farm was opened in Portugal, at the Aguçadoura Wave Park. Waves are generated by passing over the surface of the sea. As long as the waves propagate slower than the speed just above the waves. Wave height is determined by speed, the duration of time the wind has been blowing, fetch and by the depth. A given wind speed has a practical limit over which time or distance will not produce larger waves. When this limit has been reached the sea is said to be fully developed, in general, larger waves are more powerful but wave power is also determined by wave speed, wavelength, and water density. Oscillatory motion is highest at the surface and diminishes exponentially with depth, however, for standing waves near a reflecting coast, wave energy is also present as pressure oscillations at great depth, producing microseisms. These pressure fluctuations at greater depth are too small to be interesting from the point of view of wave power, the waves propagate on the ocean surface, and the wave energy is also transported horizontally with the group velocity. The mean transport rate of the energy through a vertical plane of unit width. The above formula states that power is proportional to the wave energy period. When the significant wave height is given in metres, and the period in seconds. Example, Consider moderate ocean swells, in water, a few km off a coastline, with a wave height of 3 m. Using the formula to solve for power, we get P ≈0.5 kW m 3 ⋅ s 2 ≈36 kW m, in major storms, the largest waves offshore are about 15 meters high and have a period of about 15 seconds. According to the formula, such waves carry about 1.7 MW of power across each metre of wavefront. An effective wave power device captures as much as possible of the energy flux
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Hydroelectricity
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Hydroelectricity is electricity produced from hydropower. In 2015 hydropower generated 16. 6% of the total electricity and 70% of all renewable electricity. Hydropower is produced in 150 countries, with the Asia-Pacific region generating 33 percent of global hydropower in 2013, China is the largest hydroelectricity producer, with 920 TWh of production in 2013, representing 16.9 percent of domestic electricity use. The cost of hydroelectricity is relatively low, making it a source of renewable electricity. The hydro station consumes no water, unlike coal or gas plants, the average cost of electricity from a hydro station larger than 10 megawatts is 3 to 5 U. S. cents per kilowatt-hour. With a dam and reservoir it is also a source of electricity since the amount produced by the station can be changed up or down very quickly to adapt to changing energy demands. Once a hydroelectric complex is constructed, the project produces no direct waste, Hydropower has been used since ancient times to grind flour and perform other tasks. In the mid-1770s, French engineer Bernard Forest de Bélidor published Architecture Hydraulique which described vertical-, by the late 19th century, the electrical generator was developed and could now be coupled with hydraulics. The growing demand for the Industrial Revolution would drive development as well, in 1878 the worlds first hydroelectric power scheme was developed at Cragside in Northumberland, England by William George Armstrong. It was used to power an arc lamp in his art gallery. The old Schoelkopf Power Station No.1 near Niagara Falls in the U. S. side began to produce electricity in 1881. The first Edison hydroelectric power station, the Vulcan Street Plant, began operating September 30,1882, in Appleton, Wisconsin, by 1886 there were 45 hydroelectric power stations in the U. S. and Canada. By 1889 there were 200 in the U. S. alone, at the beginning of the 20th century, many small hydroelectric power stations were being constructed by commercial companies in mountains near metropolitan areas. Grenoble, France held the International Exhibition of Hydropower and Tourism with over one million visitors, by 1920 as 40% of the power produced in the United States was hydroelectric, the Federal Power Act was enacted into law. The Act created the Federal Power Commission to regulate hydroelectric power stations on federal land, as the power stations became larger, their associated dams developed additional purposes to include flood control, irrigation and navigation. Federal funding became necessary for development and federally owned corporations, such as the Tennessee Valley Authority. Hydroelectric power stations continued to become larger throughout the 20th century, Hydropower was referred to as white coal for its power and plenty. Hoover Dams initial 1,345 MW power station was the worlds largest hydroelectric station in 1936
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William Armstrong, 1st Baron Armstrong
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William George Armstrong, 1st Baron Armstrong CB FRS was an English industrialist who founded the Armstrong Whitworth manufacturing concern on Tyneside. He was also an eminent scientist, inventor and philanthropist, in collaboration with the architect Richard Norman Shaw, he built Cragside in Northumberland, the first house in the world to be lit by hydroelectricity. He is regarded as the inventor of modern artillery, Armstrong was knighted in 1859 after giving his gun patents to the government. Armstrong was born in Newcastle upon Tyne, at 9 Pleasant Row, Shieldfield, although the house in which he was born no longer exists, an inscribed granite tablet marks the spot on which it once stood. At that time the area, next to the Pandon Dene, was rural and his father, also called William, was a corn merchant on the Newcastle quayside, who rose through the ranks of Newcastle society to become mayor of the town in 1850. An elder sister, Anne, born in 1802, was named after his mother, Armstrong was educated at private schools in Newcastle and Whickham, near Gateshead, until he was sixteen, when he was sent to Bishop Auckland Grammar School. While there, he visited the nearby engineering works of William Ramshaw. During his visits he met his wife, Ramshaw’s daughter Margaret. Armstrong’s father was set on him following a career in the law, and so he was articled to Armorer Donkin and he spent five years in London studying law and returned to Newcastle in 1833. In 1835 he became a partner in Donkin’s business and the firm became Donkin, Stable, Armstrong married Margaret Ramshaw in 1835, and they built a house in Jesmond Dene, on the eastern edge of Newcastle. Armstrong worked for years as a solicitor, but during his spare time he showed great interest in engineering. Armstrong was a keen angler, and while fishing on the River Dee at Dentdale in the Pennines, he saw a waterwheel in action. It struck Armstrong that much of the power was being wasted. When he returned to Newcastle, he designed an engine powered by water. Unfortunately, little interest was shown in the engine, Armstrong subsequently developed a piston engine instead of a rotary one and decided that it might be suitable for driving a hydraulic crane. In 1846 his work as an amateur scientist was recognized when he was elected a Fellow of the Royal Society, in 1845 a scheme was set in motion to provide piped water from distant reservoirs to the households of Newcastle. He claimed that his hydraulic crane could unload ships faster and more cheaply than conventional cranes, the Corporation agreed to his suggestion, and the experiment proved so successful that three more hydraulic cranes were installed on the Quayside. The success of his hydraulic crane led Armstrong to consider setting up a business to manufacture cranes and he therefore resigned from his legal practice
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Cragside
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Cragside is a country house near the town of Rothbury in Northumberland, England. It was the first house in the world to be lit using hydroelectric power, the property was opened to the public in 1979. At one point, the building included an observatory and a scientific laboratory. The Grade I listed house is surrounded by one of Europes largest rock gardens, a number of rhododendrons. One variety of rhododendron is named after Lady Armstrong, Lord Armstrong spent much of his time as a child in Rothbury to get away from industrial Newcastle to alleviate his ill health. He returned to Rothbury after not having a holiday for many years, the original house was completed in 1863 by an unknown architect but was transformed by architect Richard Norman Shaw between 1869 and 1884 into an imposing mansion. Cragside is an example of his English Gothic style, in 2007, Cragside reopened after undergoing total refurbishment. In 1868, an engine was installed, with water being used to power labour-saving machines such as laundry equipment, a rotisserie. The resultant electricity was used to power an arc lamp installed in the Gallery in 1878, the arc lamp was replaced in 1880 by Joseph Swans incandescent lamps in what Swan considered the first proper installation of electric lighting. The generators, which provided power for the farm buildings on the estate, were constantly extended and improved to match the increasing electrical demand in the house. The 2006 regeneration project included extensive rewiring, a new hydro-powered electricity generator was installed in 2014, it can provide 12 kW, supplying around 10% of the propertys electricity consumption. The new system uses an Archimedes screw 17 metres long, the Open University Arts Foundation Course featured Cragside in one of its programmes in 1987. The documentary series Abroad Again in Britain by Jonathan Meades focused on Cragside in episode 2, henrietta Heald, William Armstrong, Magician of the North. Ken Smith, Emperor of Industry, Lord Armstrong of Cragside
26.
England
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England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west, the Irish Sea lies northwest of England and the Celtic Sea lies to the southwest. England is separated from continental Europe by the North Sea to the east, the country covers five-eighths of the island of Great Britain in its centre and south, and includes over 100 smaller islands such as the Isles of Scilly, and the Isle of Wight. England became a state in the 10th century, and since the Age of Discovery. The Industrial Revolution began in 18th-century England, transforming its society into the worlds first industrialised nation, Englands terrain mostly comprises low hills and plains, especially in central and southern England. However, there are uplands in the north and in the southwest, the capital is London, which is the largest metropolitan area in both the United Kingdom and the European Union. In 1801, Great Britain was united with the Kingdom of Ireland through another Act of Union to become the United Kingdom of Great Britain and Ireland. In 1922 the Irish Free State seceded from the United Kingdom, leading to the latter being renamed the United Kingdom of Great Britain, the name England is derived from the Old English name Englaland, which means land of the Angles. The Angles were one of the Germanic tribes that settled in Great Britain during the Early Middle Ages, the Angles came from the Angeln peninsula in the Bay of Kiel area of the Baltic Sea. The earliest recorded use of the term, as Engla londe, is in the ninth century translation into Old English of Bedes Ecclesiastical History of the English People. According to the Oxford English Dictionary, its spelling was first used in 1538. The earliest attested reference to the Angles occurs in the 1st-century work by Tacitus, Germania, the etymology of the tribal name itself is disputed by scholars, it has been suggested that it derives from the shape of the Angeln peninsula, an angular shape. An alternative name for England is Albion, the name Albion originally referred to the entire island of Great Britain. The nominally earliest record of the name appears in the Aristotelian Corpus, specifically the 4th century BC De Mundo, in it are two very large islands called Britannia, these are Albion and Ierne. But modern scholarly consensus ascribes De Mundo not to Aristotle but to Pseudo-Aristotle, the word Albion or insula Albionum has two possible origins. Albion is now applied to England in a poetic capacity. Another romantic name for England is Loegria, related to the Welsh word for England, Lloegr, the earliest known evidence of human presence in the area now known as England was that of Homo antecessor, dating to approximately 780,000 years ago. The oldest proto-human bones discovered in England date from 500,000 years ago, Modern humans are known to have inhabited the area during the Upper Paleolithic period, though permanent settlements were only established within the last 6,000 years
27.
Siemens AG
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Siemens AG is a German conglomerate company headquartered in Berlin and Munich and the largest manufacturing and electronics company in Europe with branch offices abroad. The principal divisions of the company are Industry, Energy, Healthcare, and Infrastructure & Cities, the company is a component of the Euro Stoxx 50 stock market index. Siemens and its subsidiaries employ approximately 362,000 people worldwide, the von Siemens family remain the largest shareholder with a stake of 6. 9% percent. Siemens & Halske was founded by Werner von Siemens and Johann Georg Halske on 12 October 1847, based on the telegraph, their invention used a needle to point to the sequence of letters, instead of using Morse code. The company, then called Telegraphen-Bauanstalt von Siemens & Halske, opened its first workshop on 12 October, in 1848, the company built the first long-distance telegraph line in Europe,500 km from Berlin to Frankfurt am Main. In 1850, the younger brother, Carl Wilhelm Siemens, later Sir William Siemens. The London agency became an office in 1858. In the 1850s, the company was involved in building long distance telegraph networks in Russia, in 1855, a company branch headed by another brother, Carl Heinrich von Siemens, opened in St Petersburg, Russia. In 1867, Siemens completed the monumental Indo-European telegraph line, in 1867, Werner von Siemens described a dynamo without permanent magnets. A similar system was independently invented by Charles Wheatstone. In 1881, a Siemens AC Alternator driven by a watermill was used to power the worlds first electric lighting in the town of Godalming. The company continued to grow and diversified into electric trains and light bulbs, in 1890, the founder retired and left running the company to his brother Carl and sons Arnold and Wilhelm. In 1887, it opened its first office in Japan, Siemens & Halske was incorporated in 1897, and then merged parts of its activities with Schuckert & Co. Nuremberg in 1903 to become Siemens-Schuckert, in 1907, Siemens had 34,324 employees and was the seventh-largest company in the German empire by number of employees. In 1919, S & H and two companies jointly formed the Osram lightbulb company. During the 1920s and 1930s, S & H started to manufacture radios, television sets, in the 1920s, Siemens constructed the Ardnacrusha Hydro Power station on the River Shannon in the then Irish Free State, and it was a world first for its design. The company is remembered for its desire to raise the wages of its workers only to be overruled by the Cumann na nGaedheal government. Siemens exploited the forced labour of deported people in extermination camps, the company owned a plant in Auschwitz concentration camp
28.
Dynamo
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A dynamo is an electrical generator that produces direct current with the use of a commutator. Today, the simpler alternator dominates large scale power generation, for efficiency, reliability, a dynamo has the disadvantages of a mechanical commutator. Also, converting alternating to direct current using power rectification devices is effective, the word dynamo was originally another name for an electrical generator, and still has some regional usage as a replacement for the word generator. The word dynamo was coined by Werner von Siemens in 1882, the original dynamo principle of W. Siemens meant only the direct current generators which use exclusively the self-excitation principle to generate DC power. The earlier DC generators which used permanent magnets were not considered dynamo electric machines, the invention of the Dynamo principle was a huge technological leap over the old traditional permanent magnet based DC generators. The discovery of the dynamo principle made the industrial scale electric power generation technically and economically feasible, a small electrical generator built into the hub of a bicycle wheel to power lights is called a hub dynamo, although these are invariably AC devices, and are actually magnetos. The electric dynamo uses rotating coils of wire and magnetic fields to convert mechanical rotation into a direct electric current through Faradays law of induction. A dynamo machine consists of a structure, called the stator, which provides a constant magnetic field. Due to Faradays law of induction the motion of the wire within the field creates an electromotive force which pushes on the electrons in the metal. The commutator is needed to direct current. When a loop of wire rotates in a field, the magnetic flux through it. However, in the days of electric experimentation, alternating current generally had no known use. The few uses for electricity, such as electroplating, used direct current provided by messy liquid batteries, dynamos were invented as a replacement for batteries. The commutator is essentially a rotary switch and it consists of a set of contacts mounted on the machines shaft, combined with graphite-block stationary contacts, called brushes, because the earliest such fixed contacts were metal brushes. The commutator reverses the connection of the windings to the circuit when the potential reverses, so instead of alternating current. The earliest dynamos used permanent magnets to create the magnetic field and these were referred to as magneto-electric machines or magnetos. However, researchers found that magnetic fields, and so more power. These were called dynamo-electric machines or dynamos, the field coils of the stator were originally separately excited by a separate, smaller, dynamo or magneto
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Godalming
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Godalming /ˈɡɒdəlmɪŋ/ is a historic market town, civil parish and administrative centre of the Borough of Waverley in Surrey, England,4 miles SSW of Guildford. The town traverses the banks of the River Wey in the Greensand Ridge – a hilly, heavily wooded part of the outer London commuter belt, in 1881, it became the first place in the world to have a public electricity supply and electric street lighting. Godalming is 30.5 mi southwest of London and shares a three-way twinning arrangement with the towns of Joigny in France, friendship links are in place with the state of Georgia and Moscow. James Oglethorpe of Godalming was the founder of the colony of Georgia, Godalming is regarded as an expensive residential town, partly due to its visual appeal, favourable transport links and high proportion of private housing. In recent years it has ranked the UKs third most desirable property hotspot. The borough of Waverley, which includes Godalming, was judged in 2013 to have the highest quality of life in Great Britain, the town has existed since Saxon times, and probably earlier. Godalming grew in size because its location is halfway between Portsmouth and London, which encouraged traders to set up stalls and inns for travellers to buy from. Godalming Parish Church has an early Saxon chancel and a Norman tower, Godalming appears in Domesday Book of 1086 as Godelminge. It was held by William the Conqueror and its domesday assets were,2 churches worth 12s,3 mills worth £2 1s 8d,25 ploughs,40 acres of meadow, woodland worth 103 hogs. Its population was roughly 400 people, at the time, its manor belonged to the King, but a few hundred years later, ownership transferred to the Bishop of Salisbury, under a charter granted by King Edward I of England. In the year 1300, the town was granted the right to hold a weekly market and its major industry at the time was woollen cloth, which contributed to Godalming’s prosperity over the next few centuries, until a sudden decline in the 17th century. Instead, its people applied their skills to the latest knitting and weaving technology and began producing stockings in a variety of materials, a willingness to adapt from one industry to another meant that Godalming continued to thrive. For example, papermaking was adopted in the 17th century, in 1726 a Godalming maidservant called Mary Toft hoaxed the town into believing that she had given birth to rabbits. The foremost doctors of the day came to witness the freak event, eventually Toft was found out after a porter was caught smuggling a dead rabbit into her chamber, she confessed to inserting at least 16 rabbits into herself and faking their birth. Court testimony of 1764 attests to how purchasing one of the mills in Godalming and dealing in corn, so successful was Godalming that in the early 19th century it was considerably larger than Guildford, and by 1851 the population had passed 6,500. Already, it was becoming a residence for commuters, for it was connected to London by railway two years earlier, in 1849, and to Portsmouth in 1859. Today the town is served by Godalming railway station on the Portsmouth Direct Line, the first mayor of Godalming was Henry Marshall. Godalming came to attention in September 1881, when it became the first town in the world to have installed a public electricity supply
30.
Holborn Viaduct power station
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Holborn Viaduct power station, named the Edison Electric Light Station, was the worlds first coal-fired power station, generating electricity for public use. It was built at number 57, Holborn Viaduct in London, the plant began running on 12 January 1882, three years after the invention of the carbon-filament incandescent light bulb. It burnt coal to drive a turbine which drove a 27-tonne,125 horsepower generator which produced direct current at 110 volts. It initially lit 968 16-candle incandescent lamps to provide street lighting from Holborn Circus to St. Martins Le Grand, the power station also provided electricity for private residences, which may have included Ely Place. Edison opened a second coal-fired power station in September 1882 in the United States, in 1878, the City of London Corporation had installed 16 electric arc lamps over the viaduct, but the experiment was discontinued within six months, and the bridge returned to gas lighting. The Victoria Embankment was lit with electric lamps at around the same time, the Holborn Viaduct project was preceded by two months by an electricity supply from a water wheel in Godalming, Surrey - the worlds first public electricity supply. This hydroelectric project was on a smaller scale, however. Lacking the legal precedent to lay underground cables, Edisons associate Edward Hibberd Johnson discovered culverts existed on the Holborn Viaduct which would allow for electrical cables to be laid, the American-built Jumbo generator was driven by a Porter-Allen steam engine built by Babcock and Wilcox. The station was on Crown property and so could not be extended and it closed in September 1886 and the lamps were converted back to gas. The Early Days of the Power Station Industry, Cambridge University Press, ISBN9781107475045
31.
Thomas Edison
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Thomas Alva Edison was an American inventor and businessman, who has been described as Americas greatest inventor. He developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and the long-lasting, practical electric light bulb. Edison was an inventor, holding 1,093 US patents in his name, as well as many patents in the United Kingdom, France. Edisons inventions contributed to mass communication and, in particular, telecommunications and these included a stock ticker, a mechanical vote recorder, a battery for an electric car, electrical power, recorded music and motion pictures. His advanced work in these fields was an outgrowth of his career as a telegraph operator. Edison developed a system of generation and distribution to homes, businesses. His first power station was on Pearl Street in Manhattan, New York, Thomas Edison was born in Milan, Ohio, and grew up in Port Huron, Michigan. He was the seventh and last child of Samuel Ogden Edison, Jr. and Nancy Matthews Elliott. His father, the son of a Loyalist refugee, had moved as a boy with the family from Nova Scotia, settling in southwestern Ontario, in a known as Shewsbury, later Vienna. Samuel Jr. eventually fled Ontario because he took part in the unsuccessful Mackenzie Rebellion of 1837 and his father, Samuel Sr. had earlier fought in the War of 1812 as captain of the First Middlesex Regiment. By contrast, Samuel Jr. s struggle found him on the losing side, once across the border, he found his way to Milan, Ohio. His patrilineal family line was Dutch by way of New Jersey and his mother taught him at home. Much of his education came from reading R. G, parkers School of Natural Philosophy and The Cooper Union for the Advancement of Science and Art. Edison developed hearing problems at an early age, the cause of his deafness has been attributed to a bout of scarlet fever during childhood and recurring untreated middle-ear infections. In his later years, he modified the story to say the injury occurred when the conductor, in helping him onto a moving train, Edisons family moved to Port Huron, Michigan, after the railroad bypassed Milan in 1854 and business declined. Edison sold candy and newspapers on trains running from Port Huron to Detroit and he briefly worked as a telegraph operator in 1863 for the Grand Trunk Railway at Stratford, Ontario railway at age 16. He was held responsible for a near collision and he also studied qualitative analysis and conducted chemical experiments on the train until he left the job. Edison obtained the right to sell newspapers on the road, and, with the aid of four assistants, he set in type and printed the Grand Trunk Herald
32.
Babcock & Wilcox
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Babcock & Wilcox Enterprises is an American power generation company headquartered in Charlotte, North Carolina. The company was founded in 1867 in Providence, Rhode Island by partners Stephen Wilcox and George Babcock as Babcock, Wilcox & Company to manufacture, built nuclear-powered surface ship, NS Savannah. B&Ws boilers supply more than 300,000 megawatts of installed capacity in over 90 countries around the world, a reactor from B&W was destroyed by a nuclear meltdown in the Three Mile Island accident. During World War II, over half of the US Navy fleet was powered by Babcock & Wilcox boilers, the company has its headquarters in Charlotte, North Carolina. B&W also has joint major joint venture companies in Beijing and the Indian city of Pune, on June 30,2015, Babcock & Wilcox completed a spinoff from BWX Technologies, its former parent which is now headquartered in Lynchburg, Virginia. The two companies began trading separately on July 1, B&W employs approximately 5,700 people, in addition to several thousand joint venture employees. B&W PGG and its subsidiaries have facilities in Ohio, Wisconsin, Arona, Italy, Beijing, China, Esbjerg, Denmark, Babcock & Wilcox MEGTEC LLC B&W SPIG Diamond Power International, Inc. The boilers more safely generated higher pressure steam and was more efficient than existing designs, in 1891, Babcock & Wilcox Ltd is established as a separate United Kingdom company, to be responsible for all sales outside the US and Cuba. In 1902 the New York Citys first subway is powered by B&W boilers, during 1907 and 1909 Theodore Roosevelts Great White Fleet were powered by B&W Boilers. In 1929 B&W installs the worlds first commercial size recovery boiler using the magnesium bisulfite process in Quebec, between 1941 and 1945 B&W designed and delivered 4,100 marine boilers for combat and merchant ships, including 95 percent of the US fleet in Tokyo Bay at Japanese surrender. In 1942, the developed the cyclone furnace. Between 1943 and 1945 B&W provided components, materials and process development for Manhattan Project, between 1949 and 1952 B&W provided the 8 boilers for the SS United States, the fastest ocean liner ever constructed. Between 1953 and 1955 B&W designed and fabricated components for USS Nautilus, in 1961 B&W designed and supplied reactors for world’s first commercial nuclear ship NS Savannah. In 1962 B&W designed and furnished reactor systems for B&Ws first commercial reactor, Indian Point, in 1975 B&W designed and built components for liquid metal fast breeder reactors. In 1975 the long term agreements with the British Babcock & Wilcox Ltd were ended. Subsequently, the British company was renamed Babcock International Group plc, in 1978 B&W designed and built the nuclear reactor that was involved in the Three Mile Island accident. In 1999 B&W was awarded the contract to develop fuel cells, on February 22,2000, B&W filed for Chapter 11 bankruptcy in part as a result of thousands of claims for personal injury due to prolonged exposure to asbestos and asbestos fibers. Claims included asbestosis, lung cancer, pleural and peritoneal mesothelioma, as a condition of emerging from bankruptcy, B&W created a trust fund to compensate victims, but for amounts far less than settlements paid in individual personal injury lawsuits
33.
Culvert
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A culvert is a structure that allows water to flow under a road, railroad, trail, or similar obstruction from one side to the other side. Typically embedded so as to be surrounded by soil, a culvert may be made from a pipe, in the United Kingdom the word can also be used for a longer artificially buried watercourse. A structure that carries water above land is known as an aqueduct, Culverts are commonly used both as cross-drains for ditch relief and to pass water under a road at natural drainage and stream crossings. A culvert may be a structure designed to allow vehicle or pedestrian traffic to cross over the waterway while allowing adequate passage for the water. Culverts come in sizes and shapes including round, elliptical, flat-bottomed, pear-shaped. The culvert type and shape selection is based on a number of factors including requirements for performance, limitation on upstream water surface elevation. The process of removing culverts, which is becoming increasingly prevalent, is known as daylighting, in the UK, the practice is also known as deculverting. Culverts can be constructed of a variety of materials including cast-in-place or precast concrete, galvanized steel, aluminum, or plastic, two or more materials may be combined to form composite structures. For example, open-bottom corrugated steel structures are built on concrete footings. Culverts must be sized and installed, and protected from erosion. Most agencies adhere to these standards when designing, engineering, if the failure is sudden and catastrophic, it can result in injury or loss of life. Sudden road collapses are often at poorly designed and engineered culvert crossing sites, water passing through undersized culverts will scour away the surrounding soil over time. This can cause a failure during medium-sized rain events. There are more than 5,000,000 culverts currently in use in the United States alone, continued inspection, maintenance, and replacement of these structures is crucial for infrastructure and safety. Accidents due to culvert failure can occur if a culvert has not been adequately sized. Improperly designed backfill support around aluminum or plastic culverts can result in material collapse or failure from inadequate load support. Soil and sand carried through a culvert can wear away the galvanizing of a culvert, allowing it to corrode and eventually collapse. This happened at a culvert near Gosford, New South Wales in 2007, safe and stable stream crossings can accommodate wildlife and protect stream health while reducing expensive erosion and structural damage
34.
City Temple, London
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The City Temple is a Nonconformist church on Holborn Viaduct in London. It is the only English Free Church still worshipping in its own building every Sunday in the City of London, the current Minister is Rev Dr Rodney Woods. The church is part of the Thames North Synod of the United Reformed Church and is a member of the Evangelical Alliance, the City Temple is most famous as the preaching place of the 20th century liberal theologian Leslie Weatherhead. Other notable preachers have included R. J. Campbell, Joseph Fort Newton, Thomas Goodwin, the first church building on the present site was built in 1874. The congregation was founded earlier, the traditional date is 1640. Destroyed by bombing during the Second World War, it was rebuilt, the City Temple is widely believed to have been founded by Thomas Goodwin. The exact date of its foundation is unknown, but it is believed to have been around 1640 and it is the oldest Nonconformist congregation in the City of London. Its first meeting-house was located in Anchor Lane, the second minister of the Church was Thomas Harrison, who succeeded Goodwin in 1650, at which time the Church moved to a meeting-house in Lime Street. Harrisons ministry only lasted until 1655, a successor was not appointed until 1658, when Rev. Thomas Mallory was called to pastor the Church. Mallory led the Church during the period that followed the Restoration of the Monarchy in 1660. The Church moved several times but after a number of moves it found a permanent home in the Poultry. The first call, in March 1868, he declined but in June 1869 he accepted, at the same time the Church was looking to relocate from its site in Poultry. The site was sold for 50, 000GBP, the Church was then faced with the question of a new site. Parker insisted that the new site would have to be within the City of London, the Memorial Stone of the new building, to be called the City Temple, was laid by Dr Thomas Binney on 19 May 1873. The Corporation of the City of London presented a marble pulpit to the Church. The building was dedicated on 19 May 1874, the building, from its location and size, began to assume the character of a Nonconformist cathedral, and became the most important Congregational pulpit in Britain. Much of this was due to Joseph Parker, as age began to tell on Parker, Rev. Reginald John Campbell, a Congregational minister in Brighton, was called in 1902 to act as his assistant. Shortly after his agreeing to this arrangement, Dr Parker died suddenly, Parker had made it clear that it was his wish for Campbell to be his successor, and so Campbell was called
35.
Old Bailey
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The Central Criminal Court of England and Wales, commonly known as the Old Bailey from the street on which it stands, is a court in London and one of a number of buildings housing the Crown Court. The Old Bailey has been housed in several structures near this location since the 16th century, the Crown Court sitting at the Central Criminal Court deals with major criminal cases from within Greater London and in exceptional cases, from other parts of England and Wales. Trials at the Old Bailey, as at other courts, are open to the public, however, the court originated as the sessions house of the Lord Mayor and Sheriffs of the City of London and of Middlesex. It was destroyed in the Great Fire of London in 1666 and rebuilt in 1674, with the court open to the weather to prevent the spread of disease. In 1734 it was refronted, enclosing the court and reducing the influence of spectators and it was rebuilt again in 1774 and a second courtroom was added in 1824. Over 100,000 criminal trials were carried out at the Old Bailey between 1674 and 1834, in 1834, it was renamed as the Central Criminal Court and its jurisdiction extended beyond that of London and Middlesex to the whole of the English jurisdiction for trials of major cases. The court was intended as the site where only criminals accused of crimes committed in the City. However, in 1856, there was public revulsion at the accusations against the doctor William Palmer that he was a poisoner and murderer and this led to fears that he could not receive a fair trial in his native Staffordshire. The Central Criminal Court Act 1856 was passed to enable his trial to be held at the Old Bailey, in the 19th century, the Old Bailey was a small court adjacent to Newgate gaol. Hangings were a spectacle in the street outside until May 1868. The condemned would be led along Dead Mans Walk between the prison and the court, and many were buried in the walk itself, large, riotous crowds would gather and pelt the condemned with rotten fruit and vegetables and stones. In 1807,28 people were crushed to death after a pie-sellers stall overturned, the present Old Bailey building dates from 1902 but it was officially opened on 27 February 1907. It was designed by E. W. Mountford and built on the site of the infamous Newgate gaol, above the main entrance is inscribed the admonition, Defend the Children of the Poor & Punish the Wrongdoer. King Edward VII opened the courthouse, on the dome above the court stands a bronze statue of Lady Justice, executed by the British sculptor F. W. Pomeroy. She holds a sword in her hand and the scales of justice in her left. During the Blitz of World War II, the Old Bailey was bombed and severely damaged, in 1952, the restored interior of the Grand Hall of the Central Criminal Court was once again open. The interior of the Great Hall is decorated with paintings commemorating the Blitz, running around the entire hall are a series of axioms, some of biblical reference. This part of the building houses the shorthand-writers offices
36.
General Post Office
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The General Post Office was officially established in England in 1660 by Charles II and it eventually grew to combine the functions of state postal system and telecommunications carrier. Similar General Post Offices were established across the British Empire, in 1969 the GPO was abolished and the assets transferred to The Post Office, changing it from a Department of State to a statutory corporation. For the more recent history of the system in the United Kingdom, see the article Royal Mail. Originally, the GPO was a monopoly covering the despatch of items from a sender to a specific receiver. The postal service was known as the Royal Mail because it was built on the system for royal. In 1661 the office of Postmaster General was created to oversee the GPO, the GPO created a network of post offices where senders could submit items. All post was transferred from the post office of origination to distribution points called sorting stations, initially it was the recipient of the post who paid the fee, and he had the right to refuse to accept the item if he did not wish to pay. The charge was based on the distance the item had been carried so the GPO had to keep an account for each item. The first general post office in London opened in 1643, just 8 years after King Charles I legalised use of the posts for private correspondence. It was probably on Cloak Lane near Dowgate Hill, coffee houses in the City such as Lloyds and Garraways organised private transport of mail among their patrons. The Royal Mail moved its headquarters to Lombard Street in the City in 1678 to better curtail such practices, when the Central London Railway was built in 1900 its nearby station was named Post Office. Smirkes building was felt to be too small by this time, however, in 1912, the former GPO East was demolished, the current headquarters of BT, a post World War II building, occupies the site of the old Telegraph Office. The theory was used to state control of the mail service into every form of electronic communication possible on the basis that every sender used some form of distribution service. These distribution services were considered in law as forms of electronic post offices and this applied to telegraph and telephone switching stations. In the mid 19th century several private companies were established in the UK. The responsibility for the electric telegraphs was officially transferred to the GPO on Friday,4 February 1870, overseas telegraphs did not fall within the monopoly. The private telegraph companies that existed were bought out. The new combined telegraph service had 1,058 telegraph offices in towns,6,830,812 telegrams were transmitted in 1869 producing revenue of £550,000
37.
Newgate
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Newgate was one of the historic seven gates of the London Wall around the City of London and one of the six which date back to Roman times. From it, a Roman road led west to Silchester, Hampshire, excavations in 1875,1903 and 1909 revealed the Roman structure and showed that it consisted of a double roadway between two square flanking guardroom towers. From the 12th century, at least, the gate was used as a prison for debtors and this, the notorious Newgate Prison, was later extended to the south on the site of the modern Central Criminal Court on Old Bailey. The gate was demolished in 1767, a notable discovery here was a Roman tile inscribed with a disgruntled comment that Austalis has been going off on his own for 13 days. To the north of the street are the ruins of Christ Church Greyfriars on the site of a medieval Franciscan monastery, to the south is Paternoster Square leading towards St Pauls Cathedral. Fortifications of London City gate Defensive wall An 18th-century map showing the location of the gate
38.
Pearl Street Station
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Pearl Street Station was the first central power plant in the United States. It was located at 255-257 Pearl Street in Manhattan on a site measuring 50 by 100 feet, just south of Fulton Street and fired by coal. It began with one direct current generator, and it started generating electricity on September 4,1882, by 1884, Pearl Street Station was serving 508 customers with 10,164 lamps. The station was built by the Edison Illuminating Company, which was headed by Thomas Edison and they were removed and replaced with new engines from Armington & Sims that proved to be much more suitable for Edisons dynamos. Pearl Street Station not only holds the distinction of being the worlds first central power plant, while the steam engines provided grid electricity, Edison made use of the thermal byproduct by distributing steam to local manufacturers, and warming nearby buildings on the same Manhattan block. The station burned down in 1890, destroying all but one dynamo that is now kept in the Greenfield Village Museum in Dearborn, in 1929 the Edison Company constructed three scale working models of the station. When a button was pushed, a motor turned the engines, generators, a set of lamps connected to labelled buttons identified the various areas of the building. The models were constructed to a scale of one-half inch to the foot and were 62 inches long,34 inches high and 13 inches wide, up to 31 people worked on constructing the models which took about 6 months to complete. Holborn Viaduct power station Schuyler Wheeler War of Currents Pearl Street Station from the IEEE Global History Network Edison, His Life, History of the Electric Power Industry. Emergence of Electrical Utilities in America
39.
Steam engine
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A steam engine is a heat engine that performs mechanical work using steam as its working fluid. Steam engines are combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as power, nuclear power or geothermal energy may be used. The ideal thermodynamic cycle used to analyze this process is called the Rankine cycle, in the cycle, water is heated and transforms into steam within a boiler operating at a high pressure. When expanded through pistons or turbines, mechanical work is done, the reduced-pressure steam is then exhausted to the atmosphere, or condensed and pumped back into the boiler. Specialized devices such as hammers and steam pile drivers are dependent on the steam pressure supplied from a separate boiler. The use of boiling water to mechanical motion goes back over 2000 years. The Spanish inventor Jerónimo de Ayanz y Beaumont obtained the first patent for an engine in 1606. In 1698 Thomas Savery patented a steam pump that used steam in direct contact with the water being pumped, Saverys steam pump used condensing steam to create a vacuum and draw water into a chamber, and then applied pressurized steam to further pump the water. Thomas Newcomens atmospheric engine was the first commercial steam engine using a piston. In 1781 James Watt patented an engine that produced continuous rotary motion. Watts ten-horsepower engines enabled a range of manufacturing machinery to be powered. The engines could be sited anywhere that water and coal or wood fuel could be obtained, by 1883, engines that could provide 10,000 hp had become feasible. The stationary steam engine was a key component of the Industrial Revolution, the aeolipile described by Hero of Alexandria in the 1st century AD is considered to be the first recorded steam engine. Torque was produced by steam jets exiting the turbine, in the Spanish Empire, the great inventor Jerónimo de Ayanz y Beaumont obtained a patent for the first steam engine in history in 1603. Thomas Savery, in 1698, patented the first practical, atmospheric pressure and it had no piston or moving parts, only taps. It was an engine, a kind of thermic syphon, in which steam was admitted to an empty container. The vacuum thus created was used to water from the sump at the bottom of the mine
40.
War of the currents
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It took place during the introduction and rapid expansion of the alternating current standard and its eventual adoption over the direct current distribution system. This was a period of consolidation and by 1890 over a dozen electric companies had merged down to three, Edison, Thomson-Houston, and Westinghouse. By the early 1890s the latter two were generating profits far in advance of the DC-based Edison company, during this period Thomas Edison left the electric power business and the company he founded was beginning to add AC technology to its system. The merger of the Edison company with Thomson-Houston created a company now controlled three quarters of the US electrical business. Westinghouse won the bid to supply power for the Worlds Columbian Exposition in 1893. Their lead in the field quickly diminished with later contracts being split with General Electric, there were several technical factors that drove the adoption of alternating-current over direct-current. The direct-current system generated and distributed power at the same voltage as used by the customers lamps. This required the use of large, costly distribution wires and forced generating plants to be near the loads, alternating-current generating stations could be larger, more efficient, and the distribution wires were relatively less costly. The lower cost of AC power distribution prevailed, though DC systems persisted in urban areas throughout the 20th century. While DC power is not used generally for the transmission of energy from power plants into homes as Edison and others intended and it is used widely in all modern electronic devices such as computers, telephones, and automotive systems. The war of currents grew out of the development of two lighting systems, arc lighting running on alternating current and incandescent lighting running on direct current. Both were supplanting gas lighting systems, with arc lighting taking over large area/street lighting, the first type of widely used electric light was the arc lamp. These lamps had been around for most of the 19th century, arc lighting systems were extremely brilliant and capable of lighting whole streets, factory yards, or the interior of large buildings. They needed high voltages and some ran better on alternating current, in 1878 inventor Thomas Edison saw a market for a system that could bring electric lighting directly into a customers business or home, a niche not served by arc lighting systems. By 1882 the investor-owned utility Edison Illuminating Company was established in New York City, Edison direct current systems would be sold to cities throughout the United States, making it a standard with Edison controlling all technical development and holding all the key patents. Direct current worked well with incandescent lamps, which were the principal load of the day, direct-current systems could be directly used with storage batteries, providing valuable load-leveling and backup power during interruptions of generator operation. Direct-current generators could be paralleled, allowing economical operation by using smaller machines during periods of light load. Edison had invented a meter to allow customers to be billed for energy proportional to consumption, direct current also worked well with electric motors, an advantage DC would hold throughout the 1880s
41.
Utility frequency
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The utility frequency, line frequency or mains frequency is the nominal frequency of the oscillations of alternating current in an electric power grid transmitted from a power station to the end-user. In large parts of the world this is 50 Hz, although in the Americas, current usage by country or region is given in the list of mains power around the world. During the development of electric power systems in the late 19th and early 20th centuries. Large investment in equipment at one frequency made standardization a slow process, however, as of the turn of the 21st century, places that now use the 50 Hz frequency tend to use 220–240 V, and those that now use 60 Hz tend to use 100–127 V. Both frequencies coexist today with no technical reason to prefer one over the other. Unless specified by the manufacturer to operate on both 50 and 60 Hz, appliances may not operate efficiently or even if used on anything other than the intended frequency. In practice, the frequency of the grid varies around the nominal frequency, reducing when the grid is heavily loaded. However, most utilities will adjust the frequency of the grid over the course of the day to ensure a constant number of cycles occur and this is used by some clocks to accurately maintain their time. Several factors influence the choice of frequency in an AC system, lighting, motors, transformers, generators and transmission lines all have characteristics which depend on the power frequency. All of these factors interact and make selection of a power frequency a matter of considerable importance, the best frequency is a compromise between contradictory requirements. When large central generating stations became practical, the choice of frequency was made based on the nature of the intended load, eventually improvements in machine design allowed a single frequency to be used both for lighting and motor loads. A unified system improved the economics of electricity production, since system load was more uniform during the course of a day, the first applications of commercial electric power were incandescent lighting and commutator-type electric motors. Both devices operate well on DC, but DC could not be changed in voltage. Commutator-type motors do not operate well on high-frequency AC, because the changes of current are opposed by the inductance of the motor field. Though commutator-type universal motors are common in AC household appliances and power tools, they are small motors, less than 1 kW. The induction motor was found to work well on frequencies around 50 to 60 Hz, once AC electric motors became common, it was important to standardize frequency for compatibility with the customers equipment. Generators operated by slow-speed reciprocating engines will produce lower frequencies, for a number of poles, than those operated by, for example. For very slow prime mover speeds, it would be costly to build a generator with enough poles to provide a high AC frequency, as well, synchronizing two generators to the same speed was found to be easier at lower speeds
42.
Frequency changer
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A frequency changer or frequency converter is an electronic or electromechanical device that converts alternating current of one frequency to alternating current of another frequency. The device may also change the voltage, but if it does, traditionally, these devices were electromechanical machines called a motor-generator set. Also devices with mercury arc rectifiers or vacuum tubes were in use, with the advent of solid state electronics, it has become possible to build completely electronic frequency changers. These devices usually consist of a stage which is then inverted to produce AC of the desired frequency. The inverter may use thyristors, IGCTs or IGBTs, a battery may also be added to the dc circuitry to improve the converters ride-through of brief outages in the input power. Frequency changers vary in power-handling capability from a few watts to megawatts, aside from the obvious application of converting bulk amounts of power from one distribution standard to another, frequency changers are also used to control the speed and the torque of AC motors. In this application, the most typical frequency converter topology is the three-phase two-level voltage source inverter, the phase voltages are controlled using power semiconductor switches and pulse width modulation. Semiconductor switching devices and anti-parallel connected freewheeling diodes form a bridge, the PWM changes the connections of the phases between the positive and the negative dc-link potentials so that the fundamental wave voltage has the desired frequency and amplitude. The motor reacts primarily to the frequency and filters out the effects of harmonic frequencies. Another application is in the aerospace and airline industries, often airplanes use 400 Hz power so a 50 Hz or 60 Hz to 400 Hz frequency converter is needed for use in the ground power unit used to power the airplane while it is on the ground. Airlines might also utilize the converters to provide in-air wall current to passengers for use with laptops, in renewable energy systems, frequency converters are an essential component of doubly fed induction generators as used in modern multi-megawatt class wind turbines. Frequency changers are used to control the speed of motors, primarily pumps. In many applications, significant energy savings are achieved, the most demanding application areas are found on industrial processing lines, where the control accuracy requirements can be very high. This is particularly true in the power and weapons industry. The STUXNET worm targets specific Siemens brand frequency converters, causing erratic operation of Irans centrifuge plant, an HVDC-system can serve as frequency converter for large loads. Frequency converter may also refer to a circuit that converts radio frequency signals at one frequency to another frequency. Cascade converter Motor-generator Static inverter plant Variable-frequency drive HVDC
43.
Steam turbine
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A steam turbine is a device that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft. Its modern manifestation was invented by Sir Charles Parsons in 1884, in 1551, Taqi al-Din in Ottoman Egypt described a steam turbine with the practical application of rotating a spit. Steam turbines were described by the Italian Giovanni Branca and John Wilkins in England. The devices described by Taqi al-Din and Wilkins are today known as steam jacks, in 1672 an impulse steam turbine driven car was designed by Ferdinand Verbiest. A more modern version of car was produced some time in the late 18th century by an unknown German mechanic. The modern steam turbine was invented in 1884 by Sir Charles Parsons, the invention of Parsons steam turbine made cheap and plentiful electricity possible and revolutionized marine transport and naval warfare. Parsons design was a reaction type and his patent was licensed and the turbine scaled-up shortly after by an American, George Westinghouse. The Parsons turbine also turned out to be easy to scale up. Parsons had the satisfaction of seeing his invention adopted for all major world power stations, a number of other variations of turbines have been developed that work effectively with steam. The de Laval turbine accelerated the steam to full speed before running it against a turbine blade, De Lavals impulse turbine is simpler, less expensive and does not need to be pressure-proof. It can operate with any pressure of steam, but is less efficient. He taught at the École des mines de Saint-Étienne for a decade until 1897, one of the founders of the modern theory of steam and gas turbines was Aurel Stodola, a Slovak physicist and engineer and professor at the Swiss Polytechnical Institute in Zurich. His work Die Dampfturbinen und ihre Aussichten als Wärmekraftmaschinen was published in Berlin in 1903, a further book Dampf und Gas-Turbinen was published in 1922. It was used in John Brown-engined merchant ships and warships, including liners, the present-day manufacturing industry for steam turbines is dominated by Chinese power equipment makers. Other manufacturers with minor market share include Bhel, Siemens, Alstom, GE, Doosan Škoda Power, Mitsubishi Heavy Industries, the consulting firm Frost & Sullivan projects that manufacturing of steam turbines will become more consolidated by 2020 as Chinese power manufacturers win increasing business outside of China. There are several classifications for modern steam turbines, Turbine blades are of two basic types, blades and nozzles. Blades move entirely due to the impact of steam on them and this results in a steam velocity drop and essentially no pressure drop as steam moves through the blades. A turbine composed of alternating with fixed nozzles is called an impulse turbine, Curtis turbine, Rateau turbine
