14th PRIMARY SCHOOL OF ACHARNES Principal: Paul Kosmetatos Address: Lefkados & Theagenous Phone: ++030 210 2316721 e-mail: mail@14dim-acharn.att.sch.gr g-mail: 14dimacharn@gmail.com skype: dimacharn14 site: http://14dim-acharn.att.sch.gr
14th PRIMARY SCHOOL OF ACHARNES
6th GRADE
Sun
Our bright friend or enemy? Head TeacherS: Kalogera Eftych委伪 - TZIMAS DIMITRIS
School Year: 2013 -2014
14th PRIMARY SCHOOL OF ACHARNES
6th GRADE
Sun Our bright friend or enemy? Head TeacherS
Kalogera Eftych委伪 TZIMAS DIMITRIS School Year: 2013 -2014
Sun: Our bright friend or enemy? 6th Grade School year: 2013-2014 Teachers responsible for the project: Kalogera Eftychia, Tzimas Dimitris 14th PRIMARY SCHOOL OF ACHARNES Principal: Paul Kosmetatos Address: Lefkados & Theagenous Phone: ++030 210 2316721 e-mail: mail@14dim-acharn.att.sch.gr g-mail: 14dimacharn@gmail.com skype: dimacharn14 site: http://14dim-acharn.att.sch.gr Shape: 14 x 21 Pages: 64 Front cover & Layout: Synthesis, tel: ++030 210 381 38 38 Print - production: Synthesis, Vassilis Gramelis
Contents Part one The Sun as a star
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Part two The benefits of the sun to mankind
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Part three The benefits of the sun for animals and plants
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Part four Objects that base their operation on the Sun
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Part five The negative effects the sun
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Part six How can we properly guard against the sun?
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Part seven Kids are drawing
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Introductory note The book you have in your hands was created from the sixth grade students’ project work during the school year 20132014. We decided this year to be occupied with the study of the sun and its affects upon earth. We wanted to spread this information to our peers, our parents but also to all those who will read this book. In addition, this work was integrated in the framework of the Comenius 2012-2014 program, «Healthy European Citizens», So our friends and partners of the schools in Murcia (Spain), in Dobrova (Slovenia), in Wodzislaw (Poland), in Piegaro (Italy) and in Werl (Germany) can learn about the centre of our solar system. We would like to thank our teachers Mrs. Eftychia Kalogera and Mr Tzimas Dimitris for their inspiration and guidance, our principal Mr Paul Kosmetatos, as well as the rest of the teachers who supported this effort, the Parents’ Association and Mrs. Helen Pediotis, for their assistance in the procedures and the technical sections. The 6th grade students
The authors and students of the 6th Grade Aivazi Raphaella Anagnostou George Archontakis George Basioukas Nick Gialouri Marilena Gikas Apostolis Guri Marcel Christos Dimopoulos Karagiannopoulos Thomas Loli Christina Maniatis Vasilis Manolaki Nefeli
Palamida Joanna Papadatou Kelly Papadomanolakis Philemon Pappa Georgia Patereli Matina Petropoulou Katerina Plota Georgina Rodi Evangelia Spatiotis Demosthenes Trivela Marichrysa Tsiadis Gregory Chatzopoulou Vasiliki
part one The Sun as a star
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The Sun is the star of our solar system and the brightest star in the sky. It’s almost a perfect sphere with a diameter of 1.4 million kilometers (109 times more than the Earth), and the mass of the (2 x 1030 kg) is 99.86% of the mass of the solar system. The luminosity is such that during the day will not permit, due to the strong light scattering, other celestial stars to appear (except for the Moon and Venus rarely). The Sun is the nearest star to Earth, at a distance of 149,600,000 km. Sun’s nucleus is located in the center of the solar sphere with a diameter of about 175,000 miles (0.25 solar radii). It is estimated that in the region of the center of the density of solar material is 70 to 150 times greater in the water, while the pressure reaches 2 x 1011 atmospheres. Under such conditions and with a temperature of 13.6 x 106 degrees, atoms
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of the elements are in the ionized state and compressed so that the material of the solar core although gaseous is more consistent and from solids. As a result the radiation of the inner layers of the core causes pressure on the overlying layers. The importance of the Sun in the development and maintenance of life on Earth is crucial, as the fundamental process of photosynthesis provides the energy needed for the development of living organisms and keeps the surface temperature of the Earth within tolerable levels for life. Also, causing meteorological phenomena. Its importance has been known since prehistoric times, with the result that the sun is worshiped as a deity. According to ancient Greek mythology, by Homer and Hesiod, Sun was the son of the Titan. Sun was driving his fiery chariot to heaven and had two sisters, the goddess of the moon Moon and the goddess of the dawn Io . The sun is often depicted as a young man with a
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halo on his head standing on his chariot, wearing a cloak and a globe. Roosters and eagles associated with the Sun. In Odyssey the Odysseus and the surviving crew arrived in an island, dedicated to the Sun Deity, which Circe was calling the sun Ultravioletion rather than Helios. On the Island were kept the sacred red cattle of the Sun. Despite Odysseus orders, his men disrespectfully killed and ate some of the sacred red cattle of the Sun. The guardians of the island, Daughters of the Sun, said to their father about their disrespectful acts so he destroyed the ship and killed all the men except Odysseus.
part two The benefits of the sun to mankind
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The rays of the sun are of vital importance for humans. Sun offers so much for humans but also in animals, plants and even microorganisms. Τhe Sun is well known for the enormous healing abilities. Nowadays people avoid sun exposure because of the harmful effects on them, such as skin cancer and premature aging. However, these results are derived only from excessive exposure to the sun and should not keep us away from him. In fact, solar radiation provides many benefits on our health. Some of the benefits of the sun are: Strengthens the bones and muscles: The sun’s rays increase the presence of vitamin D in the body, which is essential for the immune system, but mainly for musculoskeletal. Has the ability to deposit calcium in bones making them healthy and strong, and simultaneously, alleviates the problems of the joints. To exploit the beneficial properties of this vitamin, you should eat foods that contain it in large quantities as t is dairy products. It helps the heart: According to some studies, the rate of heart attacks is higher in countries with less sunshine. This means that the sun is good for the cardiovascular system. The heat of solar radiation causes dilation of the arteries, increased blood flow, better circulation and fewer heart attacks. However, exposure to sun should be controlled because excessive exposure causes increased body temperature and, therefore, increases the heart work and tiring. In order to have good heart health we should eat food which is rich in minerals, such us potassium, iodine and magnesium, which are found mainly in vegetables. Sun helps our psychology: The sun is the source of life. Without it we could not survive. To avoid, fear Sun like it is our
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worst enemy means to deny the benefits provided by the Sun. The sun has antidepressant activity, as the rays increase the production of endorphins, chemicals associated with our mood. Protects from tumors: Some American and British medical journals confirm that the sun can prevent the emergence of tumors. Sun is Increasing vitamin D. As According to scientists, the lack of the vitamin may be responsible for the development of breast cancer and colon. The researchers based on these data advise to have 5-10 minutes sunbathing at least 2-3 times a week, without using sunscreen oil. Sunbathing should be made ei ther before 11 am or after 4 pm. Gives a peaceful sleep: In summer, on average, the quality of sleep is much better. This depends on melatonin, the hormone that helps us sleep. The production is stimulated by darkness and is blocked from light. So, if we completely avoid the sun, our brain will “think” that there is not enough light to stop the production of the hormone. So then we feel tired and weak. Therefore we cannot sleep easily. Apart from sun exposure for a god sleep we can drink a glass of milk before going to bed. Helps to lose pounds: the sun helps us start a proper diet as it increases the production of serotonin, the neurotransmitter that regulates hunger. Make hair beautiful and strong: The ultraviolet radiation, together with the disinfectant action of seawater, is effective against the problems of the scalp.
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Removes pimples and blackheads: Ultraviolet radiation kills microorganisms and cleans the skin, restoring the production of sebum to normal levels, resulting in pimples to disappear. It treats various skin conditions: The sun is an old practice used today to treat certain skin disorders, whose symptoms subside with the effect of solar radiation. All the above benefits of the Sun are provided by the controlled use of the Sun and always with the use of suitable sunscreen oil.
Researches According to a new study conducted in Denmark, sunbathing boosts heart health and reduces the chances of premature death from heart problems. The study conducted by scientists in the University of Copenhagen, who analyzed the data from previous studies that were
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conducted in Denmark, on the health of the inhabitants of the country over the age of 40 years. As mentioned in their report, published in the journal Epidemiology, those who don’t avoid the sun are of in better heart health and lower risk of dying from premature death by 50%. They insist, moreover, that this is true for people who are infected with non-melanoma skin cancer, which are less likely to suffer a heart attack by 4%. Previous research had shown that the sun and enhances bone health, as it helps the body to synthesize vitamin D. However, the new study also caused reactions, and scientists in Britain said the Daily Mail that prolonged exposure to sunlight and UV radiation deceiving and above all the risk of contracting skin cancer.
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In their report, the researchers from Denmark said that the sun can provide the human body with the benefits, such as including the synthesis of vitamin D, when outdoor activities are within the normal range, without exaggeration and with the necessary protection. Eventually, the sun is not only the implacable enemy and causing irreparable damage to the health of our excessive exposure to radiation of the summer! Greek researchers Studies show that ultraviolet radiation has the beneficial side, as it helps in producing valuable to the human body Vitamin D. In recent years, the reduction of the ozone layer, one of the worst consequences of human activity on the Earth’s atmosphere, has increased the risk of solar radiation, increasing the incidence of skin cancer. Nevertheless, the scientists point out that excessive “Sun phobia” leads to many other health problems, which are derived from hypovitaminosis recommending sun exposure, even in the era of climate change, as long as we handle exposure with care.
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The Benefits for health from sun exposure, it may be multiple major by risks posed for cancer development skin, according to a recent scientific research. The Researchers by university of Edinburgh argue that ultraviolet radiation of sun (UV) combats ultraviolet tension, reducing risks of heart attacks and strokes. According to this research, the sunlight releasing blood components lower blood pressure. Deaths related high blood pressure, heart and strokes estimated to be up to 80 times as many deaths recoverable in skin cancer. The results of research showed that lowering blood pressure in combination with production of vitamin D, it is very important “gifts” of solar radiation for the human body.
Revealing research Revealing the research done by the scientific team Harokopio University for hypovitaminosis D. Overall, two statistical tests on a representative sample of 404 primary school children, aged 9-13, in Greece (Athens, Thessaloniki, Crete, Agrinio), which showed higher rates of hypovitaminosis D in obese girls compared with overweight or normal weight girls (59.1% versus 32.9% and 26.1% respectively). Overall, the survey results showed high levels of hypovitaminosis D for the Greek population aged 9-13 years, particularly since the vitamin plays a fundamental role in skeletal development during childhood and adolescence, maintaining bone health during adulthood and seems to protect the body from various diseases. This means that children need vitamin D to build strong bones and adults to keep their bones healthy.
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“The Greeks 30% suffer from hypovitaminosis D, while living in sunny country. According to the survey, this is even worse in obese”, says Professor o – A director of Pediatrics at the University of Athens, George Chrousos.” Indeed, there is a positive correlation between hypovitaminosis and metabolic syndrome caused by the combination of stress and obesity in humans. Lack of vitamin D is associated more with osteomalacia, a painful disease, which is often confused with osteoporosis, she adds and concludes: “The vitamin has many actions beyond-bone – and the lack of it can affect metabolism, psyche and immunity. The treatment consists of taking vitamin D for correction levels and daily as prevention”. In Greece, although the country with sun, hypovitaminosis seen in adolescents aged 15-18 to 47% in the winter, the girls have the preeminence. At ages 13-14 years, The phenomenon occurs in 13% -14%. Study of the Institute of Child Health showed that in late winter (early March) most primary school children had vitamin D levels much lower than the lower limit. The reduced synthesis of vitamin D due to the sunscreen oil usage that is otherwise shield for skin cancer. It is characteristic that sunscreen oil with SPF 8 can reduce the synthesis of the vitamin in the skin by 92.5%, while the ratio of 15 to 99%.
Reduced activity of the Sun Scientists warn that the recent reduced in activity in the Sun could lead to a mini ice age as us was in the 17th century some European countries and became known in history as the phenomenon “Maunder Minimum”.
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Even more alarming is the fact that this decline is noted while we are at solar maximum, the peak in 11 years of cycling activity of the Sun. Usually this period, the surface activity of the sun is too strong, but this time the massive explosions in the Sun’s corona, solar flares and plasma jet have been reduced, causing great impression on scientists. The solar activity decreases with amazingly fast and scientists monitor developments with great anxiety about seeing if the vertical drop will continue. During the second half of the 17th century the Sun entered a very quiet phase (Maunder Minimum). Indeed, according to historical records that period sunspots virtually disappeared. “There are strong suspicions that today the Sun behaves the same way”, said Dr. Lucie Green of the Space Sciences Laboratory Mullard, University College London. “I am a solar physicist for 30 years and I never saw anything like that. If you want to see when the Sun was so ineffective in the past should get back one hundred years back”, said Richard Harrison, head of space physics.
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Vitamin D - the vitamin of the Sun If they said to you that it exists a “medicine” which can build robust bones, it strengthens your immunogenic system and it decreases the danger for diabetes, cardiopathies, cancer and Altschaimer and it is free of charge, you would believe it? However, enough scientists believe that this medicine exists already also is vitamin D or differently the “vitamin of the Sun”.
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What is Vitamin D? Vitamin D is a fat burner vitamin which is shaped in the organism mainly via the absorption of solar ultraviolet radiation by the skin, but also by certain foods riches in vitamin D. The two forms (metabolites) the vitamin D is ergokalsiferoli (vitamin D2) which is included in the foods and cholikalsiferoli (vitamin D3) which is produced in the skin via his report by the ultraviolet radiation of the sun. In reality however is not vitamin but pre-steroids hormone, which has direct action in our genes. The final product of her metabolism, Kalsitrioli (1,25-dihydroxyvitamin D), is a pre-steroids hormone which interacts with more than 2,500 genes in the human body.
Who is at risk for lack of Vitamin D; ➼ People with limited exposure to sunlight. ➼ Excessive use of sunscreens. ➼ People with dark skin. ➼U rbanization and the trend of working in confined spaces, as well as some clothing habits in some people. ➼ Babies who are breastfeeding and children in development. ➼ Pregnant women and those who breastfeed. ➼P ostmenopausal women who have an increased risk of osteoporosis. ➼P eople older than 50 years, because the ability to synthesize vitamin D decreases with age. ➼S ubjects with diseases of fat malabsorption as celiac disease Crohn, cystic fibrosis and pancreatitis.
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➼P eople with liver and kidney disease or enzyme deficiencies. ➼P eople living in the northern hemisphere (latitude greater than 35°) especially during the winter. ➼ Hypoparathyroidism. ➼ Obese people.
What are the risks from a lack of Vitamin D? Miscellaneous scientific studies have linked the lack or insufficiency of vitamin D with the following conditions: ✤C hildren can cause Rickets, a disease of bone that leads to poor growth with weak bones, delayed growth and immunodeficiency. ✤ n adults may also have effects on bone health causing Osteomalacia and Osteoporosis. About 6% of men and more than 20% of women over age 50 suffer from osteoporosis, and 1 in 5 men and 1 in 3 women will suffer an osteoporotic fracture after the age of 50. Also, the 75% of women with osteoporosis do not know about their health issue. ✤ T he deficiency of vitamin D, can lead newborns and young children for the rest of their lives with the risk of developing rheumatoid arthritis, diabetes, Parkinson’s, Alzheimer’s, multiple sclerosis, inflammatory bowel, all because of a malfunctioning of the immune system. ✤P eople with low levels of vitamin D may develop cancer of the rectum and colon, the endometrium, the breast, the skin, the pancreas, the prostate or lymphoma .
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✤ L ow levels of vitamin D have been associated with risk factors for cardiovascular disease such as ultraviolettension, myocardial infarction, stroke, HF and with diabetes .
What are the risks of ultraviolet vitaminosis of vitamin D? Sometimes (although rarely) presented facts toxicity from excessive intake of vitamin D. Some symptoms of toxicity that are elevated blood calcium levels caused by increased intestinal calcium absorption, bone loss and formation of kidney stones. Toxicity of Vitamin D is known to be a cause of high blood pressure. Gastrointestinal symptoms of the toxicity of vitamin D may include anorexia, nausea and vomiting. These symptoms are often followed by polyuria, polydipsia, weakness, anxiety, pruritus (itch), and eventually renal insufficiency. Other studies indicate an increased risk of ischemic heart disease because of vascular calcification. Therefore, administration of vitamin D without measuring the levels of, may lead to toxicity with undesirable results.
ATTENTION!!!
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Sources of Vitamin D? The human organism can compose the 90% of vitamin D via the ultraviolet radiation of the Sun and only the 10% via the nutrition. With the exception of the greasy fishes, the liver and the egg, the remain foods contain minimal vitamin D. Certain foods (milk, juice orange, cerial) can be strengthened with vitamin D but in very low levels. In a lot of industrial countries they are enriched with vitamin D some selectively foods. The levels of vitamin D can be increased however considerably from the exposure in the solar light. Theoretically, the daily exposure in sunlight for some minutes is in position to cover the daily needs of organism in particular vitamin. 15-20 minutes of exposure in the solar light from the 10 am up to 2 pm, without sunscreen oil, 3 times a week is capable time interval so that it provides in the organism the required quantity of vitamin D. In that time interval the human organism can produce 10.000 up to with 20.000 units (IU) vitamin D. However, particularly in the winter, a lot of individuals do not engage sufficient quantity of vitamin D via the solar radiation. Also the production of vitamin D from the organism is decreased with the years, with result lack of production in bigger ages, however infrequent are the cases of insufficiency of vitamin D and in younger individuals. Also, sunscreen oil that are considerably for the protection from the cancer of skin, due to solar radiation, they impede considerably the shaping of vitamin D. Other factors that affect negatively in the shaping of vitamin D from the skin are, the melanine of skin which act as filter at the ultraviolet radiation, the pollution of atmosphere and the hole of ozone and regions with geographic width bigger than 35째.
part three The benefits of the sun for animals and plants
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Sunlight is necessary and indispensable to life, exercise vitalizing effect on the body of animals and plants. The sun sustains health, kills pathogens and has disinfecting power. Light is fundamental to life. Plants contain varying levels of chlorophyll which absorbs sunlight in red and blue in the process of photosynthesis. The rate of photosynthesis increases as light intensity, up to a maximum point beyond which remains constant. Ultraviolet light has been proven harmful to bacteria and is believed to act in inhibiting plant growth and spread at high altitudes. As the intensity of plants classified in: ➼ Sun plants: adapted at high intensities ➼ Shade plants: custom low intensities ➼ Species exhibit both characteristics by age Most plants hormonally responsive to seasonal changes of the duration of light (photoperiodism). The flowering plants are divided into: ➼L ong day: bloom when approaching the spring and day length begins to grow (typically after the winter solstice in the northern hemisphere). Examples: spinach, wheat. ➼S hort day: bloom when winter approaches and daylight length gradually shortens. Examples: tobacco, chrysanthemums, hemp ➼N eutral: bloom regardless of the duration. Examples: tomato, radish In birds and fish the photoperiodism determines the migrated, the migration and breeding times. In many bird species the reproductive organs are enlarged in spring.
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In mammals, although the photoperiodism has less effect, these are divided into: ➼ Long day: spawn when approaching spring. In this category are small mammals high latitude fast reproductive rates and short times of gestation. Examples: hares, rats. ➼S hort day: spawn in the fall so young to be born in the spring when conditions are more favorable. Examples: goats, deer. ➼N eutral: spawn throughout the entire year. Examples: man.
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In the insect photoperiodism has slower responses. Usually controls the time of larval emergence and winter withdrawal on the ground. All living organisms need energy to be able to grow. The animals get the energy they need by eating other organisms. Plants synthesize their food. The process by which plants make their food is photosynthesis. The first observations of the phenomenon of photosynthesis were made by Joseph Priestley , in 1771 . He first noticed that the green plants purify the air that was contaminated by the respiration of animals. Observations Priestley continued the Dutch doctor Inkenchaous. The de F. de Saussure Nicolas (Nicolas Théodore de Saussure) demonstrated in 1804 that the weight of oxygen, which is discharged together with the weight of the plant after the photosynthesis, is greater than the weight of
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carbon dioxide absorbed. During the 20th century the phenomenon of photosynthesis was studied from each side (biochemical, chemical, physiological, etc.). The 1941 first made experiments with radioactive isotopes and investigated the complex series of patterns for different reactions. This process is necessary in light of the Sun and a special pigment found in leaves and called chlorophyll. Thus understand that photosynthesis is only the green parts of the plant, ie leaves, since there is chlorophyll (chloroplasts). But let’s see in detail the phenomenon of photosynthesis: The leaves absorb carbon dioxide from the air, like water to the roots from the soil and the stem reaches all parts of the plant. Glucose Produced on the leaves of the plant. The energy needed for the plant to synthesize glucose comes from the
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sunlight. The plant converts solar energy to chemical energy, since glucose contains chemical energy. Those plants are energy converters! Glucose produced starch that is the plants food. The starch of the sheets transported to all parts of the plant. During photosynthesis of the leaf oxygen is released in the environment. This is why they named forests, “the lungs of the Earth”. That is the reason why it is important to protect the forests.
part four Objects that base their operation on the Sun
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Solar water heater History: the solar water heater began to be used after the petrol crisis in the ‘70s and in the mid-80s began to be used in countries with sunshine. In Cyprus there is a solar water heating for every five residents, while in Israel their use is mandatory in new buildings. As in many other countries use them subsidized by the state. Greece in the dissemination of solar devices is impressive, the first heater built in 1974, in 1980 there were about one hundred and fifty thousand square meters of collectors and in 2004 about three million square meters of collectors. Part of this success of solar water heaters in Greece due to fiscal stimulus was adopted by the Greek state. Today’s solar panels are used by more than one million people. Until recent years, Greece was one of the main manufacturers of solar water heaters. Parts: Solar water heaters, by their nature, are composed of two main parts: ➼ T he collection section (solar panels, the surface absorption of solar radiation) ➼ T he storage portion (the water storage tank) These two parts are assembled together and connected by piping, but in larger systems can be separately and used pumps to circulate the heated medium, especially when the storage section is not in the same room with the collection department. The storage portion also has electrical resistance heater with Tam, in order to produce hot water and in bad weather. The expensive solar water heaters and some have little control components such as overpressure valves or automatic vents.
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Solar panels: The main part of a solar water heater is solar panels or mirrors, which is the surface solar radiation. This consists of four parts: ➼ T he collection plate radiation ➼ T he pipes of the water flow ➼A glass cover plate and absorption ➼ T he thermally insulated box on which the remaining components are mounted. Operation of solar collectors: the operation of the solar water heater collectors based in the greenhouse that grows in the space between the plate absorption Ms L glass coating. The sunlight falls on (usually black) absorber plate, raising its temperature. The plate in turn emits radiation feature q (thermal radiation) for which the window covering is almost transparent plexiglass plate q. So long radiation (heat) is trapped between the plate and the glass, thereby increasing the efficiency for heating the water (circulating in tubes which is in contact with the plate at the rear of or incorporated in this).
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The critical factors for the good performance of the system is highly absorbent plate solar radiation, the low emissivity of the plate to a long radiation and high opacity of the crystal for second. The materials that offer better performance-price is glass and surface of aluminum or copper, colored in black. Storage tank: The water storage tank has a capacity ranging from 100 to 200 liters for normal household applications. The capacity is a function of collector surface available. It is usually steel, with an inner lining for corrosion protection. This coating is usually a plastic or epoxy paint or enamel alternatively and in more expensive systems storage tank can be copper or stainless steel. Outside there is a very good insulation from polyurethane or fiberglass.
Solar lights Solar lighting for the garden have advantages and disadvantages: they do not consume power or need any form of wiring! The cheap solar lights usually provide lighting that is much lower than electric. If we want to buy solar lights that illuminate with relative abundance (but again less than those of the electricity) should give a reasonable amount of money. Solar garden light individually!!! Solar garden light ideal for garden lovers!!! Easy to
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use!!! No need instructions to work!!! It offers functionality as it does not require electricity!!!* It is economical because it works with no electricity consumption.
Mini-dimensional solar calculator Designed in such a way that it represents the application of calculator smartphones. The device is powered by solar energy. It has all the necessary functions of a calculator, such as storing the results in memory, Finding the square root and decimal operations. compact design. Colorful buttons for ease of use. To function requires one AG10 battery.
Photovoltaic With the generic term Photovoltaic called industrial assembly of many photovoltaic cells in a row. In essence it is artificial semiconductor (usually silicon) which are combined in order to create an electrical circuit in series.
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Semiconductors they absorb photons from sunlight and produce an electrical voltage. This process is called “photovoltaic effect”. The photovoltaic belong in the category of Renewable Energy Sources (RES). In the category of renewable solar energy, solar thermal systems are more efficient than photovoltaic.
Solar Car A solar car is an electric vehicle powered near solar energy obtained from solar panels on the car. Solar cars are not currently a practical form of transportation as they can only work during the day and can only carry one or two passengers. However, competing in competitions such as the World
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Solar Challenge and American Solar Challenge. These events are often supported by government agencies such as United States Department of Energy keen to promote the development of alternative energy technology such as solar cells.
Solar vehicles Cockpit driver The driver’s cockpit is normally single-seat cars containing some room for a second passenger. It’s hot from the solar panels and very limited with few of the comforts of a normal car. They contain some of the features available to drivers of traditional vehicles such as brakes, accelerator, signals, rear view mirrors, ventilation and often cruise control. They also have a radio two ways to communicate with their support crews. Solar cars are installed with gauges seen in conventional cars and the engine drivers’ main priority is to watch these counters to identify potential problems. The drivers also have a safety harness and optionally a helmet similar to the racecar drivers.
Electrical System The electrical system is the most important part of the car’s systems as it controls all of the power entering and leaving the system. battery pack plays the same role in a solar car that a petrol tank plays in a normal car in storing power for future use. Solar cars use a range of batteries including lead-acid batteries, nickel-metal hydride (NiMH), nickel-cadmium batteries (NiCd), lithium ion batteries and lithium polymer batteries. The lead-acid batteries are less expensive and easier to work with but have less power to weight ratio. Typically, solar car use trends between 84 and 170 volts. The instrument control electronics power and regulates the electricity of the car. The components of power electronics in-
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clude the maximum power trackers, the engine controller and data acquisition system. The maximum power trackers manage the power coming from solar array to maximize the power and either deliver it to save the battery or be used in the machine. They also protect the batteries from overcharging. The engine controller manages the electricity flowing in the machine according to the signals flowing from the accelerator. Many solar cars have complex data acquisition systems that control the entire electrical system and even the most basic cars have systems that provide information on the battery voltage and current to the driver. One such system uses Controller Area Network (Solar cars usually have three wheels, but some have four). Tricycles are usually two front wheels and one rear wheel: the front wheel drive and rear wheel follows. Four wheel vehicles are set up as normal cars or similarly to three vehicles with two rear wheels close together.
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Solar series The solar array consists of hundreds of photovoltaic solar cells convert sunlight to electricity. The cars can use various solar cell technologies most often polycrystalline silicon, monocrystalline silicon or gallium arsenide. The cells are wired together in series and sequences are often wired together to form a committee. The committees have normal trends close to the nominal battery voltage. The main objective is to get as many cells in a shortest possible time. The designers put the cells encapsulated to protect them from the N weather and breakage. The design of a solar array is not as easy as tying with string just bunch of cells together. A solar array acts as part of micro-batteries all hooked together in series. The total voltage produced is the sum of all cell voltages. The problem is that if a single cell is in the shade acts as a diode, blocking the current flow for the entire series of cells. To remedy against this, designers series using the bypass diodes in parallel with the smaller parts of the series of cells, permit current to flow around non-functioning cell (s). Another consideration is that the battery itself to force current backwards through the series unless there blocking diodes can put at the end of each committee. The power produced by the solar array depends on the weather, the sun’s position and ability range. At midday a bright day, a good number can produce over 2 kilowatts (2,6 HP). Ecofriendly. According to Mr. Hadjievangelou, these cars are completely silent, completely eco-friendly environment, since they have as main characteristic the conversion of solar radiation into electricity. Also, these vehicles moving with speed between 30-40 km per hour, can be on the go all day, however, with the continuous improvement of photovoltaic and use lithium
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batteries, which have reduced weight and increased capacity, Mr. Hadjievangelou optimistic that we will soon see solar cars on public roads, as happens in vehicles that run on solar energy will be extremely cheap.
In circulation the first solar car Car and minibus operated by solar energy produced at the Faculty of Technology, University Adiyaman. The vehicles came into circulation after the administration of the necessary authorization called’ “Firat Force 01” and “Commagene 02”. The solar car will serve as the official vehicle while the minibus will be used for transporting patients. Vehicles with a range of 60-70 km and a maximum speed of 90 km will participate in international competitions. Solar vehicles that cost 210,000 Turkish Liras, will only cost 5 to 6,000 pounds if you start mass production. Meanwhile vehicles designed for use within the city and reaching speeds up to 50 kilometers per hour move very carefully.
The solar cars evolve Last week, a car designed and built by the University of South Wales, the solar Sunwift Ivy, broke the world speed record solar car. In the naval base HMAS Albatross, in the hallway of Nooura, the car recorded 88 km/h (almost 55 mph), beating the previous record of 79 km/h (49 mph).
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Although it can be extremely fast, this car is powered only by solar cells and silicon have removed all the batteries, which is an achievement. The technologies developed in this car will be used in actual solar and electric vehicle (EV) in the future. The Sunswift Ivy “created from scratch” last year. “We broke the record at 10:32 am” said project director Sunswift, Daniel Friedman last Friday. “We did not expect the sun to reach the top at noon, so the fact that he broke the record so early was a great success”. During three days of testing, the weather was cloudy and sometimes there was rain. Indeed one member joked that probably should change the name of the model in Cloudswift . The judges of the Guinness World Book of Records was present at the time of the show i therefore performance is formally documented. Although usually guides the tests are students, professional drivers Barton Mawer and Craig Davis of Tesla led thanks for this attempt.
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Difficult at present, but we will see in the future Pioneers teachers assistants and students by the Institute of Cyprus Following the initiative of the Cyprus Institute in cooperation with the municipalities of Paphos and Yeroskipou and the Neapolis University of Pafos, in 2010 launched a pioneering institution for Cyprus. Solar cars made by teachers with their students take part in a “silent” race. The solar vehicle race, which aims to achieve a green future, has become an official annual event, which brings together schools from every corner of Cyprus. According to the Institute, this is an original game that seeks to raise public awareness as regards the use of renewable energy. “s” “S” contacted yesterday by Mr. Socrates Hadjievangelou, Assistant Director and responsible solar car Technical School St. Lazarus, which three years the organization had the pleasure to be found in the awards podium. Mr. Hadjievangelou us informed about everything concerning solar vehicles, expressing also appeal to society to embrace this effort and focus on using solar energy instead of fuel.
Ecofriendly As explained Mr. Hadjievangelou, these cars are completely silent, completely eco-friendly environment, since they have as main characteristic the conversion of solar radiation into electricity. Also, these vehicles moving with speed between 30-40 km per hour, can be on the go all day. Their construction and their success is due to hard work paid together students and teachers.
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“The main role in guiding the creation and planning work for the construction of solar vehicles have fellow teachers, but who seek the full involvement of students in research. The students are participants in the construction, welding, various components and suspension systems and navigation. This is our School our goal anyway. Students gain knowledge and experiences through new programs, which will help them to further their training so that when they finish school, they manage to stand in the market”, said assistant director of the school.
Solar cars for public... Asked whether this idea can be extended to the commercial industry, Mr. Hadjievangelou seemed hesitant, but to exclude such a possibility in the future. “Investigations are currently in the experimental stage, since it is the first solar cars made in Cyprus and is used solely for educational purposes. Timidly, though, and walked to the road, although the size of its vehicles does not allow them to move next to normal cars”, he said. However, with the continuous improvement of photovoltaic and use lithium batteries, which have reduced weight and increased capacity, Mr. Hadjievangelou confident that very soon we will see solar cars on public roads, such as in foreign countries. In Switzerland, even such cars moving normally. As informed Own Solar Vehicle technical school St. Lazarus, the Swiss were present in the first race in 2010 in Paphos. “In the first competition held in Cyprus, the Swiss have brought with them and their vehicle, which sends authorization and moved normally in Nicosia. Not raced but was present”, said Mr. Hadjievangelou.
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Cypriots are Way back... The solar vehicles manufactured in Cyprus is solely for educational purposes. Unlike foreign countries, these vehicles have been registered in Cyprus, unfortunately, we are still far behind. The organization of the CREF paved the way, but should be followed by others, constructing more modern vehicles that run on solar energy. As stated troubled Mr. Hadjievangelou, “such actions would make individuals to invest large funds to promote the use of solar energy”. “We in Cyprus, we have abundant sources of energy, we have to turn to because they benefit the economy, environment, health and our land. But we and our governments to target these areas and stand next to such initiatives, and not just spectators”, he said. Finally, on behalf of the school St. Lazarus, Assistant Director thanked all those who work for research or manufacturing or helping financially, hoping that the wider community will become more aware and will help all those involved in this project.
Solar cars from the future If looking futuristic images of car do you think concerning science fiction movie or a comic book shortchange. Cars from the future is. In fact, designed for (near future;). Automakers than hybrid and electric vehicles give weight to solar cars, solar flying, moving directly to the energy of the sun and do not harm the environment at all...
Nissan iV The Mazda developed the Nissan iV, which weighs 500 pounds less than a standard drive shaft and was developed
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in 2035. The entire car is covered by a photovoltaic material, 99% lighter than glass, which absorbs solar energy and also allowing visibility for passengers. The autonomy of the battery reaches 1,200 miles.
Volkswagen Peter Wilkins created this project from the Volkswagen, which is driven by hydrogen features and photovoltaic cells. It is a very expensive model that is intended to be released in just 200 vehicles.
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Fluxion Transport The Fluxion Transport of Slavs Popovski is centered on the year 2100, when a new generation of vehicles will be necessary. Provided the movement with four magnetic ion engines, which feed each wheel separately with 200 kilowatts, allowing speeds up to 500 km/h. Engines are power by photovoltaics on the roof. (Here the PT.1)
part five The negative effects the sun
The sun is the only substantial source of energy for our planet. The sun’s energy reaches the earth in the form of radiation. Solar radiation is the most important factor shaping the Earth’s climate, because of the unequal distribution of the surface thereof. It is present in all physical and chemical processes, as well as the phenomena that occur in nature, such as: The blue color of the sky, the light, the rainbow, the twilight. The light is one of the most relevant events in our lives. We can see because we have the appropriate organs (our eyes) who feel the intensity (brightness) and wavelength (color) of light.
Effects of solar radiation are: ➼ T he uneven heating of the Earth that contributes to the creation of the winds and the circulation of the atmosphere. ➼ I n water evaporation and cloud formation ➼ I n plant photosynthesis. ➼ T he reserves of fossil fuels
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The solar spectrum (i.e. sunlight) comprises three zones: ➼U V ➼ T he Visible ➼ Infrared Factors affecting UV 1. The ultraviolet solar radiation is strongly absorbed by ozone found in the upper atmosphere (stratosphere). The decreasing the content of ozone in the atmosphere results in an increase of UV radiation on the ground, and vice versa. Main ultraviolet radiation source is the sun. It’s dangerous radiation and ozone layer protects the earth’s surface from it. That is why the ozone hole is a serious ecological problem. 2. Ultraviolet radiation is stronger when there are no clouds. The clouds generally attenuate solar radiation, but how effectively this happens depends on the thickness and type of clouds. Sparse or scattered clouds have a very small impact (about 10%), while the low and black clouds cause significant attenuation (up to 80%). Under certain conditions and for very short periods of isolation and bright clouds can lead to a slight increase of radiation. When the solar disk is visible, then the attenuation of UV by clouds is almost negligible. 3. Ultraviolet radiation becomes stronger with distance vertically from the sea, because the amount of components of the atmosphere that absorb decreases with height. Measurements showed that the ultraviolet radiation is increased by about 10% for every 1000 feet above sea level.
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4. An object or a person receives radiation directly from the sun and diffuse from the sky, and reflections from the ground. The trees, grass, soil and water reflect less than 10% of UV radiation, in contrast to the fresh snow which reflects up to 80%, or the dry sand reflecting about 20% of solar radiation. Because of reflections, people in snowy areas, or sandy beaches, receive more solar radiation. 5. Approximately 95% of UV radiation penetrates the water (e.g., sea) and 50% penetrates to a depth of about 3 meters. So when we swim our body is just a few inches below the water surface, and therefore not protected from UV radiation. 6. In a cloudless day, the UV rays are strongest during the afternoon than during the morning or afternoon. The higher is the sun from the horizon, the more intense the radiation. For this reason we have summer radiation stronger than the winter. Effects of ultraviolet radiation on human Sun and Skin: All people are not equal and opposite to the sun have special characteristics, genetically defined. These characteristics determine the skin type of each person and express tanning ability. Every skin reacts to sunlight depending on the course of characteristics and mainly depending on the skin type. The skin type, graded on a scale having regard to skin color (from lighter to darker skin), hair color, the presence or absence of lentigines (freckles), photosensitivity, quality tanning. Moreover, regardless of skin type, dryness of the skin deteriorate under the sun. The same happens with the oil, which is exac-
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erbated by a thickening of the skin caused by sun exposure. Using the data systematically collected from the scientific literature, were identified nine adverse health outcomes clearly caused by UVR exposure. The nine diseases evaluated were: ➼C utaneous malignant melanoma (CMM): melanoma is a malignant cancer with high mortality rates. Between 50% and 90% of the load of disease from melanoma due to exposure UVR. ➼ Squamous cell carcinoma (SCC): This is another type of malignant skin cancer which generally progresses less rapidly than melanoma and is less likely to cause death or current disability. Of the total tumor load nosological these, 50 - 70% is attributable to exposure to ultraviolet radiation. ➼B asal cell carcinoma (BCC): This skin cancer occurs mainly in the elderly and increased slowly by local spread. The incidence and mortality of this tumor is 50 - 90% attributable to the report of UVR. ➼S quamous cell carcinoma of the conjunctiva and the cornea (SCCC): this is a rare tumor of the eye surface. Approximately 50-70% of the load of disease due SCCC attributable to UVR exposure ➼ Photoaging: the chronic effect of solar radiation associated with the development of skin lesions, called “ultraviolet keratosis due to solar radiation”. On rare occasions, these are pre-cancerous lesions. The burden of disease of these skin lesions is 100% attributable to UVR exposure. ➼ Sunburn: Sunburn can be severe and the resulting load is 100% attributable to report UVR. ➼C ortical cataract: 5% of the total nosological load of people with cataract is directly attributed to exposure UVR.
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➼ Flapper: 40-70% of load nosological disease attributed to exposure UVR. ➼ Reactivation of herpes labialis (RHL): Excessive exposure to UVR causes immune suppression and reactivation of herpes virus, 25-50% of the nosological disease load in UV exposure. The ability of the human body to protect and restore the damage caused by ultraviolet radiation, decreases in the course of our life. The skin and eyes are the organs that suffers the greatest exposure to the ultraviolet rays of the sun. Although hair and nails are more exposed, is less important in medical terms. The exposure to solar UV radiation may result in immediate and chronic health problems of the skin, eyes and immune system, as well as damage to DNA.
part six How can we properly guard against the sun?
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Sunscreen if not used properly are not effective so we suggest helpful tips for proper application: You must apply to your skin sunscreen 30 minutes before being exposed to sunlight, without forgetting the sensitive areas: ears, nose, lips, soles, palms, neck, elbows and bald head. Sunscreen should be applied plenty on skin and renewed its application every two hours for the entire time you are exposed to the sun. The swimming, wind and excessive sweating quickly remove sunscreen from the skin, so, in these cases, you should apply sunscreen often. Limit sun exposure at times when the radiation is stronger (10:00 a.m. to 4:00 p.m.). Wear hats and shirts with long sleeves when you are out in the sun. Picking clothes with a dense weave for greater protection from the sun’s rays. Always put it back in your sunscreen when you go out of the water even if the sunscreen is waterproof. Do not be fooled by a cloudy or rainy day, the rays of the sun and then is harmful to your skin, so again you need to wear sunscreen. People belonging to groups at high risk for future skin cancer occurrence, should be put sunscreen daily. Groups at risk are workers outdoors, farmers, pale etc. If an allergic reaction to sunscreen ( redness, itching or tingling of the skin ), stop using it immediately, rinse with plenty of water and contact your dermatologist. Beware of surfaces that reflect sunlight, such as sand and sea water. The shade of an umbrella or a tree is not adequate protection for your skin. Train your children to use sunscreen.
part seven Kids are drawing
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n Su
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Ma
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Hello, kids. I am the Sun
Yes in amum,, whi le
b su Put beecausnbloc b e k theurnedyou’l sun by l
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m, Mumslmeep and I fellaas burned! Iw
for Don’t sungbet the lock
Wait! ing m I’ com
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I to to put suld you All this nblock. because happened you listen. didn’t Sorry, mum
Wait! I’ll put yo ointmenut! Mummmm I can’t stand the pain
I’ll pick up our things and we’re leaving!
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Where are we going?
You’ll see. The doctor will take away the pain!
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We are going to the hospital
Are you leavin It’s a pity..g? .!
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there Here, kids,of plants. is a varietyow nice it is? Do you seseeehanimals too! We’ll
Finally we got here! Yeahhh!
I beliedon’t ve it! !
We can do photosynthesis with the help Do you of sun see how nice So weur we are? We’re o e k ma and grateful to our food e sun for that! we’r y! Y eahh health !!
Flo Oups talkwers a! ing. re ..!!
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Do my greeyonu like Sun help leaves? s An me out. of courdsewater, ! I lo Thetreesve y . n ha sha ice ve de!
are tHow rig W he a ht aboue don’tnimals! that’t naturecare s not and good !
Le littleta’s hear what t nimals to sayhey want to us
Without the sun Υοu, peo p le shou we wouldn’t carefuldl be more be able things ar with the to exist ound you ! on earth Ηello,I’m thereo!rge! Ge
Sun us tohelps in a live envirgoreat mentn-