Green Energy Means Renewable Energy Environmental Sciences Essay

unripened zip Means Renewable Energy Environmental Sciences Essay verdure nada means renewable dexterity that is vast alternative for the manipulation of fogy force outs such as petroleum. Other formulaic method utilize to can electric caral animation is such as geothermal, biomass, ocean, solar, farting, hydro, warmth content raise cells and etc. Biomass slide fastener is derived from the wastes and animal dung either by burning it or just go forth the wastes to lay off by itself to get bio kindle or biogas. Ocean vigor is gained from the ocean and there ar two types of them such as thermal get-up-and-go and mechanical zip. Hydrogen must go through reformation surgical operation or electrolysis process to be able to use for the fuel cells to provide electricity. The heading of the project is to choose seven types of renewable energies and explain its applications and advantages in detail.1. IntroductionGreen energy is sustainable energy, which means meeting the needs of the present with prohibited conciliative the future2. These alternative energy ascendants are said to be not harmful to humans and purlieu and also arenon polluting energy bloods. It basically reduces pollution and the impact on the environment that the existing energy source is ca utilize now and in the past by conventional energy sources such as fossil fuel, coal and wood. These are non renewable energy sources, also known as the brown energy1. These sources are main(prenominal)ly used in the harvest-timeion of electricity, heating and fuel for boilers. They pose excessive amount of pollutants, such as carbon monoxide and normality oxides, together with particles that could harm humans. These pollutants are the main contributors to the greenhouse gases that cause global warning. Brown energy are also types of sources that are typically reducing on our earth, which means it could not be re- pay backd to be used in future. The main aim for this athletic field on green energy is to literate the reader on what is green energy and the importance of these energy to substitute our current conventional energy resources. These plow is also to identify the main types of green energies available for the current technology practised in our world today with the history of energy development that brought to the reading of green energy.2. Green EnergySources of green energy come from the nature itself, creation free to be harvested. They are mainly derived from the sun (solar billet), cheat and piss supply. countermand turbines befuddle been used since old times to grind grains, where the term aerogenerator is derived from. A more expensive source would come from nuclear and bioenergy (biofuel and biogas).Nuclear former is also categorized in green energy as it does not produce greenhouse gases. Waste from nuclear power whole workss are problematic and self-destructive to be handled as it takes hundreds to thousands of years to decay be fore reaching the level that is not harmful to humans, workingss and the animals. But in order to completely wipe out the impost of fossil fuels to produce electricity, the number of nuclear plants has to be increased so that greenhouse gases emissions can be cut down massively.3 Energy from sun, wind and piddle are continuous but inconsistent. Rainy days that could affect solar power production and droughts that would affect body of water levels in dams are the main drawbacks of these energy sources.As renewable energy is sometimes inconsistent, excellent storage capacity is needed to store energy that are produced. It is unremarkably windier in the shadow time, but the demand would be lesser. Nuclear plants generate so much power at a particular time that they cannot be used at once. So mountainous battery banks are required in order to mesh with the electricity system and provide a consistent power supply.2.1 story of Energy DevelopmentThe history of energy consumption of human being dates back to 3000 BC where the Mesopotamians used petroleum to caulk ships and to build roads. Coals were used during the dye Age to heat up iron and shape them, as tumefy as in the Roman culture. This long history of non-renewable energy usage has urged the increase of green energy to re push through them in order to keep the future generation safe.42000 B.C.Crude oil was used to light lamps and heat up homes by the Chinese.200 B.C.Salt produced from brine using natural gas from underground by Chinese.600 B.C.Static Electricity found by Thales of Miletus by rubbing amber.250 four hundred A.D.First water-powered Mills make by the Romans600 A.D.Greek Fire was invented by the Persians and Arabs, a form of burning liquid used greatly in the tough Empire as weapon.500 900 A.DWindmills were built to pump water and grind grains by the Persians.Late 1500sCoal was imported greatly by US, up to 108,000 tons until the 1800s.1700sA kite that transmitted electricity throug h its wet cord was found by Ben Franklin. A breakthrough in electricity discovery.1800-1826US had the depression electric utility.Mid 1800s-1950Wood as the primary source of fuel, but decreased after the shift back to coal.1870-1880Gas and alcohol using beginning(a) combustion engine. First U.S. power plant to produce electricity opened (Thomas Edisons Pearl Street Station)1888First wind turbine generating electricity in Cleveland, Ohio.Early 1900sgeothermal used to produce electricity commercially by the Italians1938Nuclear Fission discovered by the Germans.1940-1950The Atomic Energy Act implementation and the first electricity were produced by using nuclear power.1950sFirst silicon solar cell was invented (solar photovoltaic).1960sNational Environmental Policy Act and Clean denude Act in US implementation to protect the environment and reduce pollution.1970sDepartment of Energy (DOE) were formed. pissing from power plant was controlled with Clean Water Act in 1972.1974Developm ent of renewable energy was initiated and supported by the National Renewable Energy Laboratory.1980sFirst wind farm built in the United States.2.2 Giga watts of power produced in California.1990sNatural gas was used in almost 50percent of homes in US for heating.Towards the Greener SolutionTill 2007, 24 states adopted policies for increasing the production of renewable energy.2.2 Importance of Green EnergyResearch from scientific evidence are showing that what this present generation is doing go out impact the environment in the next 50 100 years. The fact that only one earth is known by human being urges organisation and private sectors to find solutions to reduce pollution and having a lifestyle that is more eco-friendly. A few reasons on why green energy is important.Non renewable fossil fuels burning are causing greenhouse gases that cause global warming. Carbon dioxide, methane and nitrogen oxides are released into the atmosphere, dissolving into raindrops and causing acid rains. Acid rains damages crops, plants and forests. aquatic organisms are also affected by this as lakes and rivers pH levels are altered. Human built structures such as steel bridges, marble statues and limestone buildings are being eroded by acid rain.10Figure 3 is a pie chart showing the anthropogenic greenhouse gas emissions in the U.S. by gas type. fogey fuels such as oil and coal are also supply that is not endless. Sooner or later the supply will vanish and unprocurable for future generations.Wind, water and solar energy are constant, sustainable and 100 percent clean energy. It does not cause negative impact on environment such as pollutant and waste. This energy type is free as well.Humans would benefits in health as reduced pollutants would provide cleaner and more breathable behavior. Lands would be saved as waste management is not necessary. Cleaner water for domestic usage and aquatic organism a would be available.Jobs opportunity would arise in rural areas as most r enewable energy plants are located far from cities. Regional development also would benefit from this.893. Types of Green Energy3.1 BiomassBiomass is derived from farm wastes, animal wastes, plant oils, crops and some kind of garbage 11. Energy that is generated from the wastes is called bio power or bioenergy 11. Biomass can be processed further to obtain biofuels or burned directly to obtain bioenergy11. The energy obtained from burning the wastes can be converted into heat, electricity and mechanical energy 1.3.1.1 Types of biofuelsSolid form its obtained from the burning of constitutional material such as animal wastes, wood, grain and other types of garbages 11.Liquid form- its obtained straight from the plant and does not involves any burning of material 1. Biodiesel can be taken as an example for this type of form. It is extracted from vegetable oils or animal fats 11.Gas form its obtained from organic waste such as dead plant and animal wastes when the organic material br eakdown naturally without the need of oxygen 12. Biogases consist of methane that is essential in terms of natural gas 12.3.1.2 Application of biomass widely used in transportation in the form of gasesElectricity generation plantsGas produced from the biomass gasifier must be cleaned first before cooling it down and use it as a fuel to run an IC engine that is coupled together with the generator 13.Heat applicationBiomass is used as a fuel to provide energy for the fuel-fired furnace that is often used for mellow end outputs such as13 Forging furnaceOvensKilnsDryersSmall boilers assume fire process heaterRe-rolling mills3.1.3 Benefits of biomass energyBiogases that are used as fuels gives more mileage for cheaper price compared to fossil fuelsEnergy from biomass has got no ending to it since human throw wastes in daily nucleotide and animals also constantly produce muckEnergy gained from burning the wastes releases carbon dioxide to the atmosphere and the carbon dioxide that is re leased from the burning is useful for the plants in terms of photosynthesis process.Each agricultural has their wastes in terms of plants, animals dung and garbages, these materials is available locally. This can reduce the need for foreign investors in the country thus improve the nation economically as wellBiomass in mass production can reduce the increase in global temperature significantly.3.2 Ocean energyOcean energy is gained from the sea. there are two types of energy gained from the ocean such as thermal energy and mechanical energy 15. Thermal energy is gained by the difference in temperature amidst the warmer surface of the ocean and the deep cold ocean water 15. Mechanical energy is gained from tidal and wave that is used to open the turbine to provide electricity in most of the power plants available 15.3.2.1 Types of energy gained3.2.2 Thermal energyThe difference between the temperatures should be around 38 Degree Fahrenheit in order to build a power plant that can fully utilize this temperature difference to make energy 16. There are 3 types of bicycles abstruse in electricity innovation system from the heat energy such asClosed cycle The heat at the surface of the ocean water is used to vaporize an ammonia type of fluid which has low boiling point and the vapor expands to turn the turbine to produce electricity 15.Open cycle The sea water in this case is kept at low pressure in order to force it to boil at low temperature and the steam produced from the sea water is then used to rotate the turbine to activate the generator to produce electricity15.Hybrid The combination of both(prenominal) open and closed cycles is used to rotate the turbine in a most economical focussing 153.2.3 Mechanical energyTidal energy its gained as the earth rotates and the gravitational pull of the moon. The principle of tidal energy is when the tides is at spicy point the water is trapped in the dam and as the tides began to reach the low point, the trap ped water is released to rotate the turbine at high speed to generate electricity15. The concept is similar to hydroelectric power plants 6.Wave energy Existing kinetic energy from the movement of the waves is used to power up the turbine 15. The concept is simple that the waves from the ocean comes into the chamber from the right, as the rise of the waves will force the air to release from the chamber and the released air is the one that will rotate the turbine to provide electricity as shown in the figure 1 below16. The higher the waves, higher are the rotation of the turbine.http//www.energyquest.ca.gov/story_old/images/chap14_wave_2007.gifApplication of wave energy 163.3 Hydrogen and fuel cells energyHydrogen best identified as the simplest component 18. One proton and one electron are the sub elements inside an atom of enthalpy 18. It has a limitation is that it doesnt appear by its own in the earth. Hydrogen atom always combined together with other elements such as water 1718 . The molecular(a) weight of hydrogen is 1kmol and the lightest weigh among all the other natural components available in earth. Hydrogen can be separated from hydrocarbon by heating process and this is called reformation process 18. Electric current also used to separate hydrogen from water and the separation process is called electrolysis 18.Fuel cells function is to convert hydrogen to electricity directly without any other processes in between 18. Reformation of methanol, gasoline and natural gas can provide hydrogen for the usage of fuel cells 18. Methanol can be used directly for some fuel cells without any reformation process 18.3.3.1 Applications of hydrogen and fuel cellsNASA used liquid nitrogen as a fuel for the space shuttles and other rockets. Liquid nitrogen does not emit any harmful material after the combustion 18. The product of the conversion by hydrogen fuel cells is pure water that is used as drinking water by the astronauts 18.Hydrogen powered vehicles is among the growing applications of energy since hydrogen fuel cells capable of providing power for buses21. Fuel cells also can provide electricity for a residential housing area that is big as a traditional AC unit 21. It can operate 24 hours a day and 7 days a week.3.3.2 Advantages of fuel cellsEfficient conversion of energy from hydrogen to electricity without any combustion taking place and the byproduct is water1920The noise level created from an operation of a fuel cell comparatively much more quiet than the conventional motors20Easier maintenance since less moving parts20Life span is longer than a battery since it has no memory strength when its refueled10The source for fuel cells are hydrogen and it is available with water20Can reduce the nations usage of fossil fuels since fossil fuels come at higher price than hydrogen that is naturally available in the earth 20.3.4 Geothermal EnergyGeothermal energy is a form of thermal energy stored by generation of heat from radioactive decay of minerals occurring inside the earth (80 percent) and from the original formation of the planet (20 percent).6 Due to the temperature differences between the earth meaning and surface, continuous heat transfer occurs from the core to surface. Radioactive decaying of natural materials such as uranium and potassium that occurs at the core creates a temperature reaching over 5000 course Celsius and very high pressure.7 This high temperature and pressure causes melting of surrounding cooler rocks and these results in the formation of magma. This magma then heats up the rocks and water in the crust which can go up tp 370 degree Celsius.6 In the range of 10kilometers of earth surface contains heat energy that is 50000 times more than all the oil and natural gas sources in the world.7 The typical place that usually spots geothermal activities is regions with active volcanic activities. This usually occurs at places where the earth crust is thin enough to let the heat out. Earthquake a nd magma movements breaks up the rocks covering and allows water to circulate, producing natural hot springs and geysers as the heated up water reaches the surface. As these hot and pressured water forms a reservoir type of containment underground, come up are usually constructed to harvest electricity or heat.3.4.1 ApplicationsSteam produced from the reservoir containing pressured and hot water are usually used to power turbines in power plants that generates electricity (Steam Turbine), while other power plants uses the hot water in the reservoir to boil a working fluid that vaporizes and moves a turbine. Heat produced by hot water near to the earth surface can be directly used for heating purpose. The applications that utilizes these direct heat includes heating buildings and homes purpose, growing plants in greenhouses, drying crops, heating water at fish farms, and also in pasteurizing milk processes at milk industries. This is done by using geothermal heat pumps. There is als o formation of hot dry rocks, usually 4-10kilometers from earth surface. Technologies is existing to inject cold water onto these hot dry rocks, circulating them through the cracks of the rocks and conscription back the heat from another well located at the end of the water circuit.5http//www.bbc.co.uk/schools/gcsebitesize/science/images/131_geothermal_energy.gifWater pumped down through injection well and collected at production well.http//www.ucsusa.org/assets/images/ce/geopower3.gifHow geothermal heat used to power turbines.3.5 HydropowerHydro means water, so hydropower basically is the power that derived from the force of moving water and generates electricity at damn by water fall throughout the turbines. 22 The fall of water and movement is part of a constant ordinary cycle known as water cycle. Water in the earths ocean and rivers evaporates by energy from the sun and draws it ascendant as water vaporization. Once the water vapour reached the cooler air in atmosphere, it a utomatically abbreviates and forms as clouds. 23 Hence, the moisture fall to earth as rain and fill the water in oceans and rivers. The moving of water from higher ground to the lower ground with the gravitational force and it drives the water extremely powerful to assist generates electricity for daily usage of human being.23 Hydropower is a one of the worlds biggest source of renewable energy and play important role or facing challenges during period of climate vary. 24 Hydropower also is considering clean energy source because it does not release any toxins to damage the environment. 25Figure 3.1 Water cycle plot3.5.1 Types of HydropowerHydropower is primarily used to generate electricity. There are few types of hydropower which is general usage in world.Micro hydro provide few hundred kilowatts to remote villages, homes and small industries.26Pumped-storage hydroelectricity stores the water that has been pumped during low demand and generates it when demand is high.26Run-of-th e-river hydroelectricity it will intrigue the kinetic energy in rivers without using dams.26Conventional hydroelectricity power comes from the potential energy of dammed and water drives the turbine to generate electricity.27The most common type of hydropower that has been used is conventional hydroelectricity known as hydroelectricity power plant which is uses a dam on a river to store water in a reservoir. This power station is usually placed in hill areas so can build dams easily and can obtain larger water reservoir and generate huge meter of electricity. 283.5.2 How is hydroelectricity power produced?http//cwc.gov.in/Kids%20Corner_files/hydropower.gifFigure 3.2 Simple Hydropower station diagramIn hydropower station, the potential energy that stored in body of water at a given summit is converted to kinetic energy which is used to rotate the turbine and produce electricity. 28In the generation of electricity by using hydroelectric power, water is accumulated or stock up at hi gher level and guide descending through large pipes to lower level known as penstock. 29 Once the water reaches the end of the penstock with higher pressure it will hits and drives the turbine to create mechanical energy from kinetic energy. Turbines rotate the connected to shaft which is turn the generator and replace mechanical energy to electrical energy. 9 Inside the generator there is rotor that covers by turbine. Large electromagnets are attached to the rotor located within coils of cop wires called as stator. Flow of electrons is formed in the coils of stator when a generator rotor spins the magnets. 31 This produces electricity that can be step up in emf through the station transformers and centre cross transmission lines. thus, transmission line conducts electricity from hydropower plant to the distribution system. There are certain advantages and disadvantages of using hydroelectric power stationAdvantagesIt is constantly renewable remaining to the habitual nature of t he hydrologic cycle.The water that been used for generation of electricity can be utilize for irrigation, boat and fishing, kayaking and etc.Fuel is not burned so there is minimal pollution and no waste is producedUsing water to run the power plant that provided free by natureDisadvantagesOnly at limited places hydropower plant can be constructed.Dams are expensive to build.Possibility of dam collapsing3.6 Solar energySolar energy is the radiant energy emitted by the Sun that is converted into thermal or electricity energy for homes and industry usage. The amount of energy falling on the earth is given by the solar constant, but very little use has been made of solar energy. 32 Renewable and sustainable energy source such as solar energy make use of it around the world to produce electricity for number of different purpose and its use is both environmentally-friendly and cost-effective over the long term. There are varieties of technologies that have been used to take benefits of s olar energy. Types of technologies such as photovoltaic system is common have been used to develop solar energy for daily and powering legion(predicate) applications. 33photovoltaic system (PV) is solar cells or panels directly convert temperateness into electricity. 34 The conversion of sunlight directly into electricity (DC) will be done by solar cells. Electricity from solar cells is stored in the battery for instant or future usage and where an inverter is required to change the Direct Current (DC) to alternate Current (AC) to power the most AC appliances. 35 Photovoltaic system solar cell made of semiconducting materials that related to those used in computer chips. Once the rays are engaged by these materials, the solar energy knocks electrons loose from the atoms, via allowing the electrons to flow through the material to produce electricity. This process of converting light (photon) to electricity (voltages) is called as photovoltaic (PV) effect. 36 The simple of photovol taic (PV) system gildd in figure below that can explain about it.A diagram of how the components of a PV system interact with each other.Figure Simple Photovoltaic (PV) system with componentsThe electricity that generated can be stored or directly utilize by photovoltaic standalone system, or a huge electricity grid powered supplied by central generation plants (photovoltaic grid-tied system), or else joint with single or numerous domestic electricity generations to supply into small grid (photovoltaic hybrid system). 37 Supplying of DC and/or AC electrical load that operate independently of the electric utility grid is designed by standalone photovoltaic system. Direct-coupled system is of the simplest type of standalone photovoltaic system that the DC output of a module or set is directly connected to a DC load (figure). 38 When there is no electrical energy stored in batteries in direct-coupled system, the load can operates during the sunlight. So, common applications that used for example water pumps, ventilation fans and small circulation pumps for solar thermal water heating systems are appropriate. 38A diagram of a stand-alone photovoltaic system.Figure Direct coupled PV systemHybrid system only integrates more than one generating source, which may use an engine-generator, wind, or utility power as a ancillary power source. Initially the battery store is recharged by the photovoltaic system once insufficient the generator charges the batteries.Solar Hybrid SystemFigure Photovoltaic hybrid systemGrid tie photovoltaic system is deliberate to work with utility grid power. Direct Current (DC) power from the Photovoltaic roam into Alternating Current (AC) power is converted by the inverter. AC appliances or local utility company can make use of the direct AC power.Solar Grid-Tie SystemFigure Photovoltaic Grid Tie system3.7 Wind EnergyWind energy is the renewable power or energy which comes from the air that flowing across the earths surface. Wind energy is a converted form of solar energy. 40 Wind is exist due to uneven heats of the atmosphere by sun, the mental defectiveness of the earths landscape and rotation of the earth.41 Movement of air from region of higher pressure level to region of lower pressure level is also known as wind. When hot air increases, the atmospheric pressure will reduce at earths exterior, and the cooler air will travel in to fill up the void. In fact, flow of wind patterns are personalized by earth landscape, vegetative cover and bodies of water. One of the fastest growing sources of electricity and fastest growing markets in the world today is wind energy because is green power, sustainable, affordable, and economic development. 42 In wind turbines there are consist of horizontal and vertical axis wind turbines been designed for rotation function.3.7.1 How a wind energy or wind turbine is work?Terms of wind energy or else wind power illustrate the generation of mechanical power or electricity by using w ind. Air has mass when it is in motion, and it contains the energy of that motion, known as kinetic energy. 40 Therefore wind turbines are usually use to harvest the kinetic energy and convert it by using inverter into utilizable which can provide electricity for home, business line applications and for sale to utilities. Wind turbine also produce mechanical energy that harvested from kinetic energy to drive machinery, for instance grinding grain and pumping water, the device called as windmill or wind pump in rural place. wind energy diagramMost common method to generate electricity is by using wind turbines. Figure 1 is explaining the simple understand on working principle of wind turbines. Explanation from the figure 1, wind will turn the large turbine blades the turning energy will spins a generator shaft and produces electricity. The electricity that produced by wind turbine is Direct Current (DC) and it cannot use because household appliances and use Alternating Current (AC). Hence, inverters connect to wind turbines to the mains power of a building and used to convert the DC electricity into useable AC electricity. 43 Small-scale of wind energy does not use inverters, as an alternative using the wind energy electricity can be charge batteries, connected to buildings main power or else connected to national power grid. 44AdvantagesThere are no fossil or fuels required to generate electricity 45Wind energy does not befoul at all so does not harm environment or discharge any toxic gases7Wind energy directly can be used as mechanical energy47DisadvantagesOnce there is no wind, solar energy or geothermal energy use as alternative way to generate electricity 48Need expensive storage throughout peak production time.49Requires large scale area to build wind farm.494. ConclusionGreen energy is the only visible solution so that the future generations are not compromised