CHEMISTRY ASSIGNMENTBENNY MATTHEW S2013pecec299

SOLAR ENERGYAPPLICATIONS

Solar energy refers primarily to the use ofsolar radiation for practical ends. However, all renewable energies, other thangeothermalandtidal, derive their energy from the sun.

Solar technologies are broadly characterized as either passive or active depending on the way they capture, convert and distribute sunlight. Active solar techniques use photovoltaic panels, pumps, and fans to convert sunlight into useful outputs. Passive solar techniques include selecting materials with favorable thermal properties, designing spaces that naturally circulate air, and referencing the position of a building to the Sun. Active solar technologies increase the supply of energy and are consideredsupply sidetechnologies, while passive solar technologies reduce the need for alternate resources and are generally considered demand side technologies.[18]

Architecture and urban planning

Sunlight has influenced building design since the beginning of architectural history.Advanced solar architecture and urban planning methods were first employed by theGreeksandChinese, who oriented their buildings toward the south to provide light and warmth. The common features ofpassive solararchitecture are orientation relative to the Sun, compact proportion (a low surface area to volume ratio), selective shading (overhangs) andthermal mass.[20]When these features are tailored to the local climate and environment they can produce well-lit spaces that stay in a comfortable temperature range.Socrates'Megaron House is a classic example of passive solar design.[20]The most recent approaches to solar design use computer modeling tying togethersolar lighting,heatingandventilationsystems in an integratedsolar designpackage.[22]Active solarequipment such as pumps, fans and switchable windows can complement passive design and improve system performance.

Agriculture and horticulture

Agricultureandhorticultureseek to optimize the capture of solar energy in order to optimize the productivity of plants. Techniques such as timed planting cycles, tailored row orientation, staggered heights between rows and the mixing of plant varieties can improve crop yields.[24][25]While sunlight is generally considered a plentiful resource, the exceptions highlight the importance of solar energy to agriculture. During the short growing seasons of theLittle Ice Age, French andEnglishfarmers employed fruit walls to maximize the collection of solar energy. These walls acted as thermal masses and accelerated ripening by keeping plants warm. Early fruit walls were built perpendicular to the ground and facing south, but over time, sloping walls were developed to make better use of sunlight. In 1699,Nicolas Fatio de Duilliereven suggested using atracking mechanismwhich could pivot to follow the Sun.[26]Applications of solar energy in agriculture aside from growing crops include pumping water, drying crops, brooding chicks and drying chicken manure.[27][28]More recently the technology has been embraced by vinters, who use the energy generated by solar panels to power grape presses.[29]Greenhousesconvert solar light to heat, enabling year-round production and the growth (in enclosed environments) of specialty crops and other plants not naturally suited to the local climate. Primitive greenhouses were first used during Roman times to producecucumbersyear-round for the Roman emperorTiberius.[30]The first modern greenhouses were built in Europe in the 16th century to keep exotic plants brought back from explorations abroad.[31]Greenhouses remain an important part of horticulture today, and plastic transparent materials have also been used to similar effect inpolytunnelsandrow covers.

Transport and reconnaissance

Development of a solar-powered car has been an engineering goal since the 1980s. TheWorld Solar Challengeis a biannual solar-powered car race, where teams from universities and enterprises compete over 3,021 kilometres (1,877mi) across central Australia fromDarwintoAdelaide. In 1987, when it was founded, the winner's average speed was 67 kilometres per hour (42mph) and by 2007 the winner's average speed had improved to 90.87 kilometres per hour (56.46mph).[32]TheNorth American Solar Challengeand the plannedSouth African Solar Challengeare comparable competitions that reflect an international interest in the engineering and development of solar powered vehicles.[33][34]Some vehicles use solar panels for auxiliary power, such as for air conditioning, to keep the interior cool, thus reducing fuel consumption.[35][36]In 1975, the first practical solar boat was constructed in England.[37]By 1995, passenger boats incorporating PV panels began appearing and are now used extensively.[38]In 1996,Kenichi Horiemade the first solar powered crossing of the Pacific Ocean, and thesun21catamaran made the first solar powered crossing of the Atlantic Ocean in the winter of 20062007.[39]There are plans to circumnavigate the globe in 2010.[40]

TIDAL ENERGYTidal stream generator

Atidal stream generator,often referred to as atidal energy converter (TEC)is a machine that extractsenergyfrom moving masses of water, in particulartides, although the term is often used in reference to machines designed to extract energy from run of river or tidal estuarine sites. Certain types of these machines function very much like underwaterwind turbines, and are thus often referred to astidal turbines. They were first conceived in the 1970s during the oil crisis.[1]Tidal stream generators are the cheapest and the least ecologically damaging among thethree main formsoftidal powergeneration.[2]Tidal stream generators draw energy from water currents in much the same way aswind turbinesdraw energy from air currents. However, the potential for power generation by an individual tidal turbine can be greater than that of similarly rated wind energy turbine. The higher density of water relative to air (water is about 800 times the density of air) means that a single generator can provide significant power at low tidal flow velocities compared with similar wind speed.[3]Given that power varies with the density of medium and the cube of velocity, water speeds of nearly one-tenth the speed of wind provide the same power for the same size of turbine system; however this limits the application in practice to places where the tide moves at speeds of at least 2knots (1m/s) even close toneap tides. Furthermore, at higher speeds in a flow between 2 to 3metres per second in seawater a tidal turbine can typically access four times as much energy per rotor swept area as a similarly rated power wind turbine.

Geothermal EnergyFOR HOUSES:If youre looking to cool your home in the summer, for example, one of the uses of geothermal energy technologies is to allow you in hot times to take heat from your house, send it down pipes into the ground (where it naturally cools), and return it to your house (where it helps bring down the temperature inside). The technology typically uses a liquid like antifreeze as a carrier of that heat, which is moved about in a closed-loop piping system.One of the other main uses of geothermal energy is the same concept but in reverse in cold months. Geothermal energy technology is used to bring warmer temperatures into your home without using fossil fuels, just by tapping into a heat exchange deep below the surface of the earth. Cool, right? But geothermal energy is so much more.FARMING:Some of the common uses of geothermal energy are amongst farmers, who use geothermal energy to heat their greenhouses. Check this out (lemons grown in the middle of winter!):n Tuscany, Italy, farmers have used water heated by geothermal energy for hundreds of years to grow vegetables in the winter. Hungary is also a major user of geothermal energy, where eighty percent of the energy demand from vegetables growers is met using geothermal energy technology.Geothermal energy is also used in fish farms.

Infrastructure & Electricity:Geothermal energy is also used to heat sidewalks and roads in order to prevent freezing in the winter. Most recently, the Netherlands beganusing geothermal energy to keep bike lanes from freezingin the wintertime, for instance.

Geothermal power plants are also a good electricity generator: Flashed Steam Plants The water flash boils and the steam is used to turn turbines. Dry Steam Plants These plants rely on the natural steam that comes from the underground reservoirs to generate electricity. Binary Power Plants These plants use the water to heat a secondary liquid which vaporizes and turns the turbines. The vaporized liquid is then condensed and reused. Hybrid Power Plants In these plants, binary and flash techniques are utilized simultaneously.Its been estimated that theeconomic benefit of geothermal energy to the U.S.is about $280 million per year. It serves as a great source ofrenewable, baseload powerfor many parts of the U.S. But the potential for geothermal still exists, untapped, in a lot of areas. At last count, 450geothermal projects were under development, so people are obviously catching on.The most common use ofgeothermal energyis for heating residential districts and businesses. The first U.S. district to use geothermal energy for heating dates back to 1893.However, the French beat us by almost 500 years, as records indicate they were tapping many uses of geothermal energy back in the 15th century.