1.
Guinea-Bissau
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Guinea-Bissau, officially the Republic of Guinea-Bissau, is a country in West Africa. It covers 36,125 square kilometres with a population of 1,704,000. Guinea-Bissau was once part of the kingdom of Gabu, as well as part of the Mali Empire, parts of this kingdom persisted until the 18th century, while a few others were under some rule by the Portuguese Empire since the 16th century. In the 19th century, it was colonized as Portuguese Guinea, upon independence, declared in 1973 and recognised in 1974, the name of its capital, Bissau, was added to the countrys name to prevent confusion with Guinea. Guinea-Bissau has a history of instability since independence, and no elected president has successfully served a full five-year term. Only 14% of the population speaks Portuguese, established as the language in the colonial period. Almost half the population speaks Crioulo, a Portuguese-based creole language, the main religions are African traditional religions and Islam, there is a Christian minority. The countrys per-capita gross domestic product is one of the lowest in the world, Guinea-Bissau was once part of the kingdom of Gabu, part of the Mali Empire, parts of this kingdom persisted until the 18th century. Other parts of the territory in the current country were considered by the Portuguese as part of their empire, Portuguese Guinea was known as the Slave Coast, as it was a major area for the exportation of African slaves by Europeans to the western hemisphere. Early reports of Europeans reaching this area include those of the Venetian Alvise Cadamostos voyage of 1455, the 1479–1480 voyage by Flemish-French trader Eustache de la Fosse, and Diogo Cão. In the 1480s this Portuguese explorer reached the Congo River and the lands of Bakongo, setting up the foundations of modern Angola, some 4200 km down the African coast from Guinea-Bissau. The local African rulers in Guinea, some of whom prospered greatly from the trade, controlled the inland trade. They kept them in the coastal settlements where the trading took place. African communities that fought back against slave traders also distrusted European adventurers, the Portuguese in Guinea were largely restricted to the port of Bissau and Cacheu. A small number of European settlers established isolated farms along Bissaus inland rivers, for a brief period in the 1790s, the British tried to establish a rival foothold on an offshore island, at Bolama. But by the 19th century the Portuguese were sufficiently secure in Bissau to regard the neighbouring coastline as their own special territory, cuba also agreed to supply artillery experts, doctors, and technicians. The PAIGC even managed to acquire a significant anti-aircraft capability in order to defend itself against aerial attack, by 1973, the PAIGC was in control of many parts of Guinea, although the movement suffered a setback in January 1973 when Cabral was assassinated. Independence was unilaterally declared on 24 September 1973, recognition became universal following 25 April 1974 socialist-inspired military coup in Portugal, which overthrew Lisbons Estado Novo regime
2.
Africa
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Africa is the worlds second-largest and second-most-populous continent. At about 30.3 million km² including adjacent islands, it covers 6% of Earths total surface area and 20.4 % of its land area. With 1.2 billion people as of 2016, it accounts for about 16% of the human population. The continent includes Madagascar and various archipelagos and it contains 54 fully recognized sovereign states, nine territories and two de facto independent states with limited or no recognition. Africas population is the youngest amongst all the continents, the age in 2012 was 19.7. Algeria is Africas largest country by area, and Nigeria by population, afarensis, Homo erectus, H. habilis and H. ergaster – with the earliest Homo sapiens found in Ethiopia being dated to circa 200,000 years ago. Africa straddles the equator and encompasses numerous climate areas, it is the continent to stretch from the northern temperate to southern temperate zones. Africa hosts a diversity of ethnicities, cultures and languages. In the late 19th century European countries colonized most of Africa, Africa also varies greatly with regard to environments, economics, historical ties and government systems. However, most present states in Africa originate from a process of decolonization in the 20th century, afri was a Latin name used to refer to the inhabitants of Africa, which in its widest sense referred to all lands south of the Mediterranean. This name seems to have referred to a native Libyan tribe. The name is connected with Hebrew or Phoenician ʿafar dust. The same word may be found in the name of the Banu Ifran from Algeria and Tripolitania, under Roman rule, Carthage became the capital of the province of Africa Proconsularis, which also included the coastal part of modern Libya. The Latin suffix -ica can sometimes be used to denote a land, the later Muslim kingdom of Ifriqiya, modern-day Tunisia, also preserved a form of the name. According to the Romans, Africa lay to the west of Egypt, while Asia was used to refer to Anatolia, as Europeans came to understand the real extent of the continent, the idea of Africa expanded with their knowledge. 25,4, whose descendants, he claimed, had invaded Libya, isidore of Seville in Etymologiae XIV.5.2. Suggests Africa comes from the Latin aprica, meaning sunny, massey, in 1881, stated that Africa is derived from the Egyptian af-rui-ka, meaning to turn toward the opening of the Ka. The Ka is the double of every person and the opening of the Ka refers to a womb or birthplace
3.
Atlantic Ocean
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The Atlantic Ocean is the second largest of the worlds oceans with a total area of about 106,460,000 square kilometres. It covers approximately 20 percent of the Earths surface and about 29 percent of its surface area. It separates the Old World from the New World, the Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Eurasia and Africa to the east, and the Americas to the west. The Equatorial Counter Current subdivides it into the North Atlantic Ocean, in contrast, the term Atlantic originally referred specifically to the Atlas Mountains in Morocco and the sea off the Strait of Gibraltar and the North African coast. The Greek word thalassa has been reused by scientists for the huge Panthalassa ocean that surrounded the supercontinent Pangaea hundreds of years ago. The term Aethiopian Ocean, derived from Ancient Ethiopia, was applied to the Southern Atlantic as late as the mid-19th century, many Irish or British people refer to the United States and Canada as across the pond, and vice versa. The Black Atlantic refers to the role of ocean in shaping black peoples history. Irish migration to the US is meant when the term The Green Atlantic is used, the term Red Atlantic has been used in reference to the Marxian concept of an Atlantic working class, as well as to the Atlantic experience of indigenous Americans. Correspondingly, the extent and number of oceans and seas varies, the Atlantic Ocean is bounded on the west by North and South America. It connects to the Arctic Ocean through the Denmark Strait, Greenland Sea, Norwegian Sea, to the east, the boundaries of the ocean proper are Europe, the Strait of Gibraltar and Africa. In the southeast, the Atlantic merges into the Indian Ocean, the 20° East meridian, running south from Cape Agulhas to Antarctica defines its border. In the 1953 definition it extends south to Antarctica, while in later maps it is bounded at the 60° parallel by the Southern Ocean, the Atlantic has irregular coasts indented by numerous bays, gulfs, and seas. Including these marginal seas the coast line of the Atlantic measures 111,866 km compared to 135,663 km for the Pacific. Including its marginal seas, the Atlantic covers an area of 106,460,000 km2 or 23. 5% of the ocean and has a volume of 310,410,900 km3 or 23. 3%. Excluding its marginal seas, the Atlantic covers 81,760,000 km2 and has a volume of 305,811,900 km3, the North Atlantic covers 41,490,000 km2 and the South Atlantic 40,270,000 km2. The average depth is 3,646 m and the maximum depth, the bathymetry of the Atlantic is dominated by a submarine mountain range called the Mid-Atlantic Ridge. It runs from 87°N or 300 km south of the North Pole to the subantarctic Bouvet Island at 42°S, the MAR divides the Atlantic longitudinally into two halves, in each of which a series of basins are delimited by secondary, transverse ridges. The MAR reaches above 2000 m along most of its length, the MAR is a barrier for bottom water, but at these two transform faults deep water currents can pass from one side to the other
4.
Portugal
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Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. It is the westernmost country of mainland Europe, to the west and south it is bordered by the Atlantic Ocean and to the east and north by Spain. The Portugal–Spain border is 1,214 kilometres long and considered the longest uninterrupted border within the European Union, the republic also includes the Atlantic archipelagos of the Azores and Madeira, both autonomous regions with their own regional governments. The territory of modern Portugal has been settled, invaded. The Pre-Celts, Celts, Carthaginians and the Romans were followed by the invasions of the Visigothic, in 711 the Iberian Peninsula was invaded by the Moors, making Portugal part of Muslim Al Andalus. Portugal was born as result of the Christian Reconquista, and in 1139, Afonso Henriques was proclaimed King of Portugal, in the 15th and 16th centuries, Portugal established the first global empire, becoming one of the worlds major economic, political and military powers. Portugal monopolized the trade during this time, and the Portuguese Empire expanded with military campaigns led in Asia. After the 1910 revolution deposed the monarchy, the democratic but unstable Portuguese First Republic was established, democracy was restored after the Portuguese Colonial War and the Carnation Revolution in 1974. Shortly after, independence was granted to almost all its overseas territories, Portugal has left a profound cultural and architectural influence across the globe and a legacy of over 250 million Portuguese speakers today. Portugal is a country with a high-income advanced economy and a high living standard. It is the 5th most peaceful country in the world, maintaining a unitary semi-presidential republican form of government and it has the 18th highest Social Progress in the world, putting it ahead of other Western European countries like France, Spain and Italy. Portugal is a pioneer when it comes to drug decriminalization, as the nation decriminalized the possession of all drugs for use in 2001. The early history of Portugal is shared with the rest of the Iberian Peninsula located in South Western Europe, the name of Portugal derives from the joined Romano-Celtic name Portus Cale. Other influences include some 5th-century vestiges of Alan settlements, which were found in Alenquer, Coimbra, the region of present-day Portugal was inhabited by Neanderthals and then by Homo sapiens, who roamed the border-less region of the northern Iberian peninsula. These were subsistence societies that, although they did not establish prosperous settlements, neolithic Portugal experimented with domestication of herding animals, the raising of some cereal crops and fluvial or marine fishing. Chief among these tribes were the Calaicians or Gallaeci of Northern Portugal, the Lusitanians of central Portugal, the Celtici of Alentejo, a few small, semi-permanent, commercial coastal settlements were also founded in the Algarve region by Phoenicians-Carthaginians. Romans first invaded the Iberian Peninsula in 219 BC, during the last days of Julius Caesar, almost the entire peninsula had been annexed to the Roman Republic. The Carthaginians, Romes adversary in the Punic Wars, were expelled from their coastal colonies and it suffered a severe setback in 150 BC, when a rebellion began in the north
5.
Carnation Revolution
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The Carnation Revolution, also referred to as the 25th of April, was initially a military coup in Lisbon, Portugal, on 25 April 1974 which overthrew the regime of the Estado Novo. This movement would lead to the fall of the Estado Novo, in Portugal,25 April is a national holiday, known as Freedom Day, to celebrate the event. Portugal had been run by a dictatorship, which was considered by many to be fascist. Despite repeated appeals that the revolutionaries broadcast over the radio, asking the population to stay home, thousands of Portuguese descended on the streets and it started as a professional class protest of Portuguese Armed Forces captains against a decree law, the Dec Lei nº 353/73 of 1973. Portugals new regime pledged itself to end the wars and began negotiations with the African independence movements. By the end of 1974, Portuguese troops had withdrawn from Portuguese Guinea. This was followed by the independence of Cape Verde, Mozambique, São Tomé and Príncipe, the Carnation Revolution in Portugal also led to Portugals withdrawal from East Timor in Southeast Asia. These events prompted an exodus of Portuguese citizens from Portugals African territories. Although the regimes political police, PIDE, killed four people before surrendering, holding red carnations, many people joined revolutionary soldiers on the streets of Lisbon, in apparent joy and audible euphoria. Red is a color for socialism and communism, which were the main ideological tendencies of many anti-New State insurgents. It was the end of the Estado Novo, the authoritarian regime in Western Europe. East Timor was also offered independence, shortly before the Indonesian invasion of East Timor, after the 28 May 1926 coup détat, Portugal implemented an authoritarian regime of social-Catholic and Integralist inspiration. In 1933, the regime was recast and renamed Estado Novo, and Salazar was named as President of the Council of Ministers until 1968, when he suffered a stroke following a domestic accident. He was replaced in September by Marcello Caetano, who served as President of the Council of Ministers until he was deposed on 25 April 1974. In 1958, General Humberto Delgado—a former member of the regime—stood against the presidential candidate, Américo Tomás. Tomás won the election, but only amidst claims of electoral fraud that denied Delgado of his legitimate victory. Immediately after this election, Salazars government abandoned the practice of electing the president. During Caetanos time in office, his attempts at political reform were obstructed by the important Salazarist elements within the regime
6.
Lisbon
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Lisbon is the capital and the largest city of Portugal, with a population of 552,700 within its administrative limits in an area of 100.05 km². Its urban area extends beyond the administrative limits with a population of around 2.7 million people. About 2.8 million people live in the Lisbon Metropolitan Area and it is continental Europes westernmost capital city and the only one along the Atlantic coast. Lisbon lies in the western Iberian Peninsula on the Atlantic Ocean, the westernmost areas of its metro area is the westernmost point of Continental Europe. Lisbon is recognised as a city because of its importance in finance, commerce, media, entertainment, arts, international trade, education. It is one of the economic centres on the continent, with a growing financial sector. Humberto Delgado Airport serves over 20 million passengers annually, as of 2015, and the motorway network, the city is the 7th-most-visited city in Southern Europe, after Istanbul, Rome, Barcelona, Madrid, Athens and Milan, with 1,740,000 tourists in 2009. The Lisbon region contributes with a higher GDP PPP per capita than any region in Portugal. Its GDP amounts to 96.3 billion USD and thus $32,434 per capita, the city occupies 32nd place of highest gross earnings in the world. Most of the headquarters of multinationals in the country are located in the Lisbon area and it is also the political centre of the country, as its seat of Government and residence of the Head of State. Lisbon is one of the oldest cities in the world, julius Caesar made it a municipium called Felicitas Julia, adding to the name Olissipo. Ruled by a series of Germanic tribes from the 5th century, in 1147, the Crusaders under Afonso Henriques reconquered the city and since then it has been a major political, economic and cultural centre of Portugal. Unlike most capital cities, Lisbons status as the capital of Portugal has never been granted or confirmed officially – by statute or in written form. Its position as the capital has formed through constitutional convention, making its position as de facto capital a part of the Constitution of Portugal. It has one of the warmest winters of any metropolis in Europe, the typical summer season lasts about four months, from June to September, although also in April temperatures sometimes reach around 25 °C. Although modern archaeological excavations show a Phoenician presence at this location since 1200 BC, another conjecture based on ancient hydronymy suggests that the name of the settlement derived from the pre-Roman appellation for the Tagus, Lisso or Lucio. Lisbons name was written Ulyssippo in Latin by the geographer Pomponius Mela and it was later referred to as Olisippo by Pliny the Elder and by the Greeks as Olissipo or Olissipona. The Indo-European Celts invaded in the 1st millennium BC, mixing with the Pre-Indo-European population and this indigenous settlement maintained commercial relations with the Phoenicians, which would account for the recent findings of Phoenician pottery and other material objects
7.
Peanut
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The peanut, also known as the groundnut and the goober and taxonomically classified as Arachis hypogaea, is a legume crop grown mainly for its edible seeds. It is widely grown in the tropics and subtropics, being important to small and large commercial producers. It is classified as both a grain legume and, because of its oil content, an oil crop. World annual production of shelled peanuts was 42 million tonnes in 2014, atypically among crop plants, peanut pods develop underground rather than aboveground. It is this characteristic that the botanist Linnaeus used to assign the specific name hypogaea, as a legume, the peanut belongs to the botanical family Fabaceae, this is also known as Leguminosae, and commonly known as the bean, or pea, family. Like most other legumes, peanuts harbor symbiotic nitrogen-fixing bacteria in root nodules and this capacity to fix nitrogen means peanuts require less nitrogen-containing fertilizer and improve soil fertility, making them valuable in crop rotations. Peanuts are similar in taste and nutritional profile to tree nuts such as walnuts and almonds, the botanical definition of a nut is a fruit whose ovary wall becomes very hard at maturity. Using this criterion, the peanut is not a true nut, however, for culinary purposes and in common English language usage, peanuts are usually referred to as nuts. Cultivated peanut arose from a hybrid between two species of peanut, thought to be A. duranensis and A. ipaensis. The initial hybrid would have been sterile, but spontaneous chromosome doubling restored its fertility, the process of domestication through artificial selection made A. hypogaea dramatically different from its wild relatives. The domesticated plants are bushier and more compact, and have a different pod structure, the initial domestication may have taken place in northwestern Argentina, or in southeastern Bolivia, where the peanut landraces with the most wild-like features are grown today. From this primary center of origin, cultivation spread and formed secondary and tertiary centers of diversity in Peru, Ecuador, Brazil, Paraguay, over time, thousands of peanut landraces evolved, these are classified into six botanical varieties and two subspecies. Subspecies A. h. fastigiata types are more upright in their habit and have shorter crop cycles. Subspecies A. h. hypogaea types spread more on the ground and have longer crop cycles, the oldest known archeological remains of pods have been dated at about 7,600 years old. These may be pods from a species that was in cultivation. They were found in Peru, where dry conditions are favorable to the preservation of organic material. Almost certainly, peanut cultivation antedated this at the center of origin where the climate is moister, many pre-Columbian cultures, such as the Moche, depicted peanuts in their art. Cultivation was well established in Mesoamerica before the Spanish arrived, there, the conquistadors found the tlalcacahuatl being offered for sale in the marketplace of Tenochtitlan
8.
Palm oil
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Palm oil is naturally reddish in color because of a high beta-carotene content. It is not to be confused with palm oil derived from the kernel of the same fruit. The differences are in color, and in saturated fat content, palm oil is 49% saturated, while palm kernel oil and coconut oil are 81% and 86% saturated fats. Along with coconut oil, palm oil is one of the few highly saturated vegetable fats and is semisolid at room temperature, Palm oil is a common cooking ingredient in the tropical belt of Africa, Southeast Asia and parts of Brazil. Its use in the food industry in other parts of the world is widespread because of its lower cost. In 2004, a group called the Roundtable on Sustainable Palm Oil was formed to work with the palm oil industry to address these concerns. It is believed that traders brought the oil palm to Egypt, Palm oil from E. guineensiss has long been recognized in West and Central African countries, and is widely used as a cooking oil. European merchants trading with West Africa occasionally purchased palm oil for use as an oil in Europe. Palm oil became a highly sought-after commodity by British traders, for use as a lubricant for machinery during Britains Industrial Revolution. Palm oil formed the basis of soap products, such as Lever Brothers Sunlight soap, by around 1870, palm oil constituted the primary export of some West African countries, such as Ghana and Nigeria, although this was overtaken by cocoa in the 1880s. Palm oil, like all fats, is composed of fatty acids, Palm oil has an especially high concentration of saturated fat, specifically, of the 16-carbon saturated fatty acid palmitic acid, to which it gives its name. Monounsaturated oleic acid is also a constituent of palm oil. Unrefined palm oil is a significant source of tocotrienol, part of the vitamin E family. The approximate concentration of fatty acids in palm oil is, Red palm oil is rich in carotenes, such as alpha-carotene, beta-carotene and lycopene, many processed foods either contain palm oil or various ingredients derived from it. After milling, various oil products are made using refining processes. First is fractionation, with crystallization and separation processes to obtain solid, then melting and degumming removes impurities. Then the oil is filtered and bleached, RBDPO is the basic palm oil product sold on the worlds commodity markets. Many companies fractionate it further to produce palm olein for cooking oil, since the mid-1990s, red palm oil has been cold-pressed and bottled for use as cooking oil, and blended into mayonnaise and salad oil
9.
Mausoleum
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A mausoleuma is an external free-standing building constructed as a monument enclosing the interment space or burial chamber of a deceased person or people. A monument without the interment is a cenotaph, a mausoleum may be considered a type of tomb, or the tomb may be considered to be within the mausoleum. A Christian mausoleum sometimes includes a chapel, the word derives from the Mausoleum at Halicarnassus, the grave of King Mausolus, the Persian satrap of Caria, whose large tomb was one of the Seven Wonders of the Ancient World. Historically, mausolea were, and still may be, large, however, smaller mausolea soon became popular with the gentry and nobility in many countries. In the Roman Empire, these were often ranged in necropoles or along roadsides, however, when Christianity became dominant, mausoleums were out of use. Later, mausolea became particularly popular in Europe and its colonies during the modern and modern periods. A single mausoleum may be permanently sealed, a mausoleum encloses a burial chamber either wholly above ground or within a burial vault below the superstructure. This contains the body or bodies, probably within sarcophagi or interment niches, modern mausolea may also act as columbaria with additional cinerary urn niches. Mausolea may be located in a cemetery, a churchyard or on private land, in the United States, the term may be used for a burial vault below a larger facility, such as a church. The Cathedral of Our Lady of the Angels in Los Angeles, California, for example, has 6,000 sepulchral and it is known as the crypt mausoleum. In Europe, these vaults are sometimes called crypts or catacombs. Mausoleum of Mohammed V Bourguiba mausoleum The Dr. John Garang De Mabior mausoleum in Juba, agostinho Netos Mausoleum in Luanda, Angola. Omar Bongos Mausoleum in Franceville, Gabon, kwame Nkrumah Mausoleum Marien Ngouabis mausoleum and Pierre Savorgnan de Brazzas mausoleum in Brazzaville, The Republic of Congo. Mausoleum of the late president Felix Houphouet-Boigny in Yamoussoukro, Côte dIvoire, laurent Kabilas mausoleum in Kinshasa, The Democratic Republic of Congo. The pyramids of ancient Egypt and Nubian pyramids are also types of mausolea, Abdel Nasser Mosque, is the Mausoleum of Gamal Abdel Nasser, in Cairo, Egypt. Unknown Soldier Memorial Royal Mausoleum of Mauretania Al Hussein Mosque, Cairo – Holy Shrine and mausoleum, Qalawun Mausoleum is the Mausoleum of Qalawun, Located in Cairo, Egypt, it was regarded by scholars as the second most beautiful medieval mausoleum ever to be built. Jedars - thirteen ancient monumental Berber mausoleums located south of Tiaret, Late President Eyademas Family Mausoleum in Kara, Togo. Kamuzu Banda Mausoleum, in Lilongwe, Malawi, Dr. Bingu wa Mutharika, President of Malawi built a mausoleum in which his late first wife and Bingu himself are buried
10.
Beach
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A beach is a landform along a body of water. It usually consists of particles, which are often composed of rock, such as sand, gravel, shingle, pebbles. The particles comprising a beach are occasionally biological in origin, such as shells or coralline algae. Some beaches have man-made infrastructure, such as posts, changing rooms. They may also have hospitality venues nearby, wild beaches, also known as undeveloped or undiscovered beaches, are not developed in this manner. Wild beaches can be valued for their beauty and preserved nature. Beaches typically occur in areas along the coast where wave or current action deposits, although the seashore is most commonly associated with the word beach, beaches are also found by lakes and alongside large rivers. Beach may refer to, small systems where rock material moves onshore, offshore, or alongshore by the forces of waves and currents, the former are described in detail below, the larger geological units are discussed elsewhere under bars. There are several parts to a beach that relate to the processes that form. The part mostly above water, and more or less influenced by the waves at some point in the tide, is termed the beach berm. The berm is the deposit of material comprising the active shoreline, the berm has a crest and a face — the latter being the slope leading down towards the water from the crest. At the very bottom of the face, there may be a trough, at some point the influence of the waves on the material comprising the beach stops, and if the particles are small enough, winds shape the feature. Where wind is the force distributing the grains inland, the deposit behind the beach becomes a dune and these geomorphic features compose what is called the beach profile. The beach profile changes seasonally due to the change in energy experienced during summer and winter months. In temperate areas where summer is characterised by calmer seas and longer periods between breaking wave crests, the profile is higher in summer. The gentle wave action during this season tends to transport sediment up the beach towards the berm where it is deposited, onshore winds carry it further inland forming and enhancing dunes. Conversely, the profile is lower in the storm season due to the increased wave energy. The removal of sediment from the berm and dune thus decreases the beach profile
11.
Solar panel
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Solar panel refers to a panel designed to absorb the suns rays as a source of energy for generating electricity or heating. A photovoltaic module is a packaged, connect assembly of typically 6×10 photovoltaic solar cells, photovoltaic modules constitute the photovoltaic array of a photovoltaic system that generates and supplies solar electricity in commercial and residential applications. Each module is rated by its DC output power under standard test conditions, the efficiency of a module determines the area of a module given the same rated output – an 8% efficient 230 watt module will have twice the area of a 16% efficient 230 watt module. There are a few commercially available solar modules that exceed 22% efficiency, a single solar module can produce only a limited amount of power, most installations contain multiple modules. A photovoltaic system typically includes an array of photovoltaic modules, an inverter, a pack for storage, interconnection wiring. The most common application of solar panels is solar heating systems. The price of power has continued to fall so that in many countries it is cheaper than ordinary fossil fuel electricity from the grid. Photovoltaic modules use light energy from the Sun to generate electricity through the photovoltaic effect, the majority of modules use wafer-based crystalline silicon cells or thin-film cells. The structural member of a module can either be the top layer or the back layer, cells must also be protected from mechanical damage and moisture. Most modules are rigid, but semi-flexible ones are available, based on thin-film cells, the cells must be connected electrically in series, one to another. Externally, most of photovoltaic modules use MC4 connectors type to facilitate easy connections to the rest of the system. Modules electrical connections are made in series to achieve an output voltage and/or in parallel to provide a desired current capability. The conducting wires that take the current off the modules may contain silver, copper or other non-magnetic conductive transition metals, bypass diodes may be incorporated or used externally, in case of partial module shading, to maximize the output of module sections still illuminated. Some special solar PV modules include concentrators in which light is focused by lenses or mirrors onto smaller cells and this enables the use of cells with a high cost per unit area in a cost-effective way. Depending on construction, photovoltaic modules can produce electricity from a range of frequencies of light, hence, much of the incident sunlight energy is wasted by solar modules, and they can give far higher efficiencies if illuminated with monochromatic light. Therefore, another design concept is to split the light into different wavelength ranges and this has been projected to be capable of raising efficiency by 50%. Scientists from Spectrolab, a subsidiary of Boeing, have reported development of solar cells with an efficiency of more than 40%. Currently the best achieved sunlight conversion rate is around 21. 5% in new products typically lower than the efficiencies of their cells in isolation
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Guinea-Bissau
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Águeda Municipality, Portugal
Dakar, Senegal
Charleston, United States
Chongqing, China
Agadir, Morocco
Lagos, Nigeria
Luanda, Angola
Taipei, Taiwan[6]
Praia, Cape Verde
Ankara, Turkey[7]
