Photovoltaic: Environmental Impact and Feasibility - Term Paper Example

Photovoltaic: Environmental Impact and Feasibility Introduction Energy is power resulting from utilization ofany chemical or physical sources to provide heat or wok Moreover, energy is neither created nor destroyed but is being transformed from one form to another. Some energy converted is available for use while some are converted into the non-useful form of energy. In general, consumers and industries use energy. However, for every amount of energy source utilized, not all energy sources are wholly converted to useful forms of energy. With this, there is a need for efficient energy transformation in the world today to aid in the conservation of energy source depletion. The energy sources can come from either non-renewable or renewable sources. Renewable energy sources such as the Solar Energy are alternative ways of energy source. Solar energy is used because it is a clean source of energy and can be utilized on a small-scale basis. The utilization of solar power energy is already being promoted today. However, the established thought of the society about this technology is that the installation and operation are very costly. The photovoltaics and concentrated solar panels are thought to be very expensive that they cannot be installed in homes and local establishments. The solar technology is an alternative power source that is growing in its applicability nowadays. The US government is promoting this technology for a green economy and lesser CO2 emissions. Despite the increase in its usage, the technology still comprises about 0.1% in the US. As one of the marketing strategies of the US, they established solar incentive programs that examine the Product, Price, Place, and Promotion. The government effort entails informing the public about the technologies advantages and benefits. Furthermore, there are incentives that are given to those who opt for solar energy development. They are offered with low-interest loans ad even substantial tax credits (Renewable Northwest). Solar energy via Photovoltaics is a unique application of power that is installed becoming an integral part of the building. It provides excellent opportunities for the domestic and small-scale users resulting in considerable savings while getting the most energy. HISTORY OF PHOTOVOLTAICS The idea of photovoltaic was just a dream that was started when William Grylls Adams and his student Richard Evans Day discovered that the exposure of selenium to light produced an electric current. This discovery considered as “scientifically one of the most far-reaching importance” by Werner Von Siemens pioneered the study of quantum mechanics even before the atoms became an accepted fact. The application of photovoltaic involves the direct conversion of the received sunlight into electricity. The materials used for this technology has photoelectric effect that absorb light photons and release electrons. The captured free electrons are made to produce electric current. The photovoltaic technology started with the discovery of the photoelectric effect discovered on 1839 by Edmund Becquerel. This French physicist discovered that electric current can be produced by exposure to light. The photovoltaic concept is derived from the study of the nature of light its photoelectric effect. The first known photovoltaic module was referred as the solar battery done by two scientists Calvin Fuller and Daryl Chapin of the Bell Laboratories in 1954 (NASA). The silicon application in the solar panel energy was first applied to satellites through the efforts and insistence of Dr. Hans Ziegler. He argued that the life span of batteries is very limited as compared with the use of solar cells that could power the satellites for a number of years. In the application of the solar cells in the satellite Vanguard, putting it side by side with batteries, it turned out that batteries died for only a couple of weeks, during the life of solar cells, Vanguard sustained its communication with the Earth for years. With the technology discovered, the application of solar cells was tried in large industries where the business of solar cells started to flourish after the year 1960 (Perlin). The technology increased with the application in spacecraft and during the energy crises in the US in 1970 (NASA). RENEWABLE ENERGY Solar Energy Solar energy is a renewable energy that derives its unlimited, inexhaustible, and free source from the sun to generate electricity. The heat and corresponding light emanating from the sun are good sources of power that promises environmental advantages, economical solutions for power generations, and sustainable sources for very long time. In a solar technology, it uses various technologies of Solar Photovoltaic, Solar Thermal, or Solar heating. Solar PV is the most common application uses semiconductors in producing electricity. These semiconductors in cell-like forms are assembled into varied sized panels depending on the electricity requirement (USEPA). The application of photovoltaic cells and solar panels are designed with sunlight-capturing semiconductors formed into cells, which activates the electrons flowing through the cell to generate electricity. The heat of the sun can boil water to produce steam and drive turbines to generate electricity. There are also technologies that utilize movable mirrors and direct sunlight to a collector tower. A receiver then collects the sun’s energy that I used to boil salted water to run generator (National Geographic). The abundance of solar energy cannot be contested. Anywhere in the world, the sun has been the source of light for the earth. Solar energy offers many advantages for the environment. Energy coming from the sun does not deplete and will not run out Turning into solar energy solutions for the energy crises of the world is economical, sustainable and environmentally friendly. It offers prime benefits that promise sustainability. It can address the growing demand for energy power both now and the future. Facilities for solar energy power require large areas for the collection of solar radiation. Sites for solar energy facilities operation must be placed in regions where the sun’s rays strike directly in order to maximize collection of the sun’s energy strategically. Putting up of solar energy power plants have impacts on the land and water resources. It may intervene with the other land uses such as agriculture, mineral production, and other existing land uses. It must A large requirement of land is necessary that is required to be cleared, graded and compacted correctly during the setup. Water is also used up for solar energy power plants used for cooling system of many machines and equipment needed for the operation. The hybrid system of solar power plants that utilize photovoltaic cells uses water as cooling agent. Water is circulated throughout the photovoltaic panels for the solar cells cooling since it increases output power to about 50% (Moharram, et al.).. The prevailing installation and the corresponding function of solar energy system are costly as the technologies explored and used were still limited. Solar energy can be integrated with various technologies for greater applications, maximum efficiency and minimized cost (Lewis). Solar Technology There are two technologies involved in solar energy: Active and passive. Passive solar produces lighting and heat for structures. The sun’s energy is consumed just simply through the basic structures of buildings and establishments. Mostly, heat and light energy can be derived from the sun and used freely. An active solar energy uses various technologies of Solar Photovoltaic, Solar Thermal, or Solar heating. Solar PV is the most common application of an active solar energy offering environmentally friendly solutions when used. It uses semiconductors in producing electricity. These semiconductors in cell-like forms are assembled into varied sized panels depending on the electricity requirement (USEPA). The deployment of solar power energy is already made possible at homes. The traditional thinking about the technology requiring massive lands and high cost is already broken. They can now be installed on rooftops for the generation of electricity. It is an environment-friendly and economically attractive energy source. The prices for the PV systems have dropped significantly in the recent years to give way to viable installations on homes (Union of Concerned Scientists). The technology of solar power is already increasing due to the benefits outweighing the capital costs. The government ought to promote this technology for a cleaner country and more energy source. The application of photovoltaic cells and solar panels are already found on many machines, rooftops, spacecraft, and even on calculators. The semiconductors formed into cells captures sunlight, which activates the electrons. Electrons then flow through the cell and generate electricity. To use this application in larger scale and make power plants out of solar energy employs the same theory incorporated with various techniques and high-end technology. The heat of the sun can boil water to produce steam and drive turbines to generate electricity. A receiver then collects the sun’s energy that I used to boil salted water to run generator. ENERGY PRODUCTION AND EFFICIENCY Mechanism of Photovoltaics The photovoltaic cell operates with the use of semi-conductor materials of silicon that is famous in the application of the microelectronics industry. The silicon semiconductor wafer serves as the electric field with both the positive and negative sides. The electrons in the solar cells are released from the atoms of the silicon of semi-conductor material. The conductors on the terminals capture the released electrons and form an electric circuit thereby producing electricity. The electricity is utilized in lighting electrical appliances in gymnasium. This operating principle is shown in figure 1. Figure 1. Solar Cell or Photovoltaic Cell The Photovoltaic cells or solar cells use multiple modules that are wired together forming an array. The arrays of photovoltaic modules produce direct current (DC) electricity. There are greater amounts of electricity produced with the larger surface area of modules. The connections of the photovoltaic cells can be arranged in parallel or series depending on the required voltage as found in Figure 2. The application of Photovoltaic devices that are used single junction for the creation of the electric field. There is a single interface for the semiconductor in the Photovoltaic cells. In this design, the photons with equal to greater energy than the band gap-free the election in the electric circuit for electricity generation. The single-junction is limited to the portions where the sun’s spectrum can equal or exceed the band gap of the material absorbing the light. Lower energy photons are not used (NASA). Figure 2. Modules of Photovoltaic cells ENVIRONMENTAL IMPACT ADVANTAGES AND DISADVANTAGES The environmental impact of the Solar Energy is outweighed by the benefits of the solar power to humanity. Some environmental experts declare that the environmental impact of the solar energy is considered negligible. Solar energy is a renewable energy getting its unlimited source from the sun. There are zero gas emissions, no drilling, and fracturing requirements. The generated electricity of the about 1-kwh from the Solar power system prevents an equivalent of 170 lbs burning of coal, 105 gallons of water consumed, and 300 lbs of CO2 released into the atmosphere. There are also precautionary measures and environmental programs that can be put up to prevent the minimal effect of the solar energy especially the large scale system to make sure that the wildlife is protected and the soil is properly planted to prevent soil erosion. The National Renewable Energy Laboratory (NREL) is exploring and investigating the means to help the wildlife adapt to the put up with these large-scale solar energy systems in ecologically pristine regions (Ipeck). Challenges of Photovoltaics One of the challenges for solar energy is the intermittent source of the sunlight due to nighttime, cloudy seasons, and rain periods. Large-scale productions of solar energy power plants pose challenges. The use of photovoltaic cells is also expensive generating costs to convert electricity from the sun (EDF Energy). However, there are technologies that provide the solution to this concern. One way is to generate solar energy us to use Concentrating Solar Power (CSP) plants, and mirrors are utilized for collection of sunlight concentrating the sunlight to produce heat and steam for a conventional thermodynamic cycle. CSP can be used to generate electricity even after sunset or if the sun is behind the clouds through the heat storage system. Compared with photovoltaic cells, CSP has a higher capacity factor that can compete with other types of energy power plants (ETSAP). In addition, a battery system can transform stored energy from the sun. A team of engineers and scientist from Harvard discovered the novel battery technology that uses a metal free battery dependent on electrochemistry of quinone- small organic molecules. A breakthrough in the solar cells has been developed by Northwestern University that utilizes lead perovskite in collecting light from the sun. Perovskite is tin-based that is an excellent absorber of sunlight that can be installed in between two electric charged transport layers to conduct electricity. Lead perovskite is considered as the next big thing in photovoltaic as the material used environment-friendly, abundant in nature and provides higher efficiency in light absorbance (Science Daily) Impact to the Environment Solar energy used for power generation offers many benefits. Its impact on the environment is lighter as compared with the other sources of energy. The use of solar energy power facilities reduces carbon emissions, greenhouse gasses and other air pollutants such as volatile organic compounds in the atmosphere. It emits relatively lower greenhouse gasses primarily carbon dioxide as compared with emissions of fossil fuels and coal power facilities. Land Use Facilities for solar energy power require large areas for the collection of solar radiation. It may intervene with the other land uses such as agriculture, mineral production, and other existing land uses. Sites for solar energy facilities operation must be placed strategically so as not to hamper other existing land use. It must be placed in regions where the sun’s rays strike directly in order to maximize collection of the sun’s energy. Putting up of solar energy power plants have impacts on the land and water resources. A large requirement of land is necessary that is required to be cleared, graded and compacted properly during the setup. Water is also used up for solar energy power plants used for cooling system of many machines and equipment needed for the operation. Operation of the power plant also releases particulate matters that may contribute significantly to the nature. Thus, it is important to have a most appropriate land location for the solar energy power plant (Solareis). Water Use The generation of electricity by the Solar Energy does not require water. However, water is needed for the manufacture of the solar PV cell components. Water is also essential in the cooling system of the different components of the solar power depending on the design of the plant. Water can be developed with a close loop system for a economic approach. Hazardous Chemicals The manufacture of PV solar cells includes process that uses hazardous substances. The semiconductor industry includes chemical usage such as Hydrogen Fluoride, Hydrochloric acid, sulfuric acid, acetone, and trichloroethane. Some of these chemicals are used as cleaning agents for the solar panels while some are used for the silicon wafer. There is also the risk for silicon dust that may be inhaled by the workers. The thin films of the PV solar cells are also toxic such as copper-indium-gallium-diselenide, cadmium telluride, and gallium arsenide. They ought to to tackled and appropriately disposed due to their health and environment risks. However, the government safety programs have already regulations that ensure the health of the workers exposed to these particulates and chemicals. There are already in place regulations that require the proper handling and disposal of chemicals that pose the threat to the health and environment (UCSUSA). Ecosystem There are effects on the ecosystem for large scale solar energy power plants. These power plants can harm the desert ecosystem when they are not properly managed. The concentrated sunlight beams created by the solar power towers can kill the animals surrounding the area such as the birds, insects, and others. The use of the hazardous chemicals and substances in the operation of the power plants need to be tackled suitably in order not to permit the flow into the water system and another system. There is a high need for proper handling of these chemicals and appropriate disposal processes. For large-scale power plants, the usage of water might affect the underground wells due to massive requirement for the cooling system (Environment and Ecology). FINANCIAL SAVINGS Present measures The underlying cost of canopy PV systems relies on the efficiency of the prevailing panels. Presently, the competences of crystalline silicon PV cells within the market range from 15% to corresponding 21%. Thus, thin film PV cells ideally possess relatively efficiencies that range from 6% to 15%. Within the laboratories, relatively higher efficiencies for the PV cells can be achieved. Nevertheless, the PV cells ought to be altered for production and economics prior to reaching the expected market. The installation of PV on the buildings, homes, and gymnasiums provide an extensive range of benefits. The integration of the PV cells on the roof of gyms and buildings creates a powerful combination of energy production with the functionality of the buildings that includes include weatherproofing, overall structural support, and solar thermal collection. There is no requirement of high-value land anymore since there is no need for another separate support establishment to cater the energy generation functionality. It also provides for the buildings electricity requirements with no incurred transmission and distribution losses. The installation of PV systems provides risk reductions. The management overhead costs related to fuel consumptions and other legal costs associated with fuel price is considerably minimized. The economic assessment of PV system in the perspective of the engineering and capital assets modeling provides an excellent basis for lean manufacturing. There is provision for reduced risks, lower value costs, planning flexibility, modularity, and reversibility. The installation of roofs of domestic buildings such as garage and gymnasiums are also readily available in the market. There is innovation of PV roofing materials that allows them to fit with the conventional roof tiles and roof sheets. These installations are custom made for the roof that can save installation costs and materials costs. There are designs such as transparent and semi-transparent PV modules that allow cost-effective applications. Efficiency-Enhancing Technology Designing of the substrate for covering the PV panel that is capable of altering its underlying color thus enhancing cell technology, and it is added on the prevailing integrated new module. The lighter colors of the PVs enhance cell efficiency. Subsequently, cell efficiency escalates with the intensity of the light colored panels as it normally lowers the underlying temperature of the panels. The technology can be executed within the StRIPES creativity thereby escalating the efficiency of the panels while intensifying their prevailing aesthetics. RELIABILITY Solar Energy The benefits of the solar energy are tremendous. Primarily, it derives its source from the sun, which is inexhaustible and limitless. A natural source requires minimal effort to convert the sunlight to generate electricity. The installation of the solar energy system might require capital costs, but there is little maintenance required. There is assurance that the solar panels once installed would transmit maximum efficiency at minimal maintenance cost. There are zero emissions for the generation of electricity. The advancement of the solar energy technology is also increasing. There are novel technologies available in the market today that requires lesser capital cost with small-scale applicability. Solar Energy made Economical Solar energy system today is costly as the technologies explored and used were still limited. The widespread application of solar energy ought to be captured, stored and converted into electricity in the most cost-efficient way. There have been many studies in nanotechnology, physical science, biotechnology and science of materials that explores cost effective approaches for the use of solar energy. Solar energy can be integrated with various technologies for greater applications, maximum efficiency, and minimized cost. One of the key steps towards a more economical solar energy is the use of solar photons to capture and convert solar energy. Solar conversion devices have optimal 31% efficiency for band gaps. Photons with higher energies than the established band gaps can release rapidly releasing only a useful internal energy. Technology for photons that can produce more voltage from the energy absorbed is explored as the solution for solar energy power (Lewis). Nanotechnology also provides solutions for making solar energy economical. It provides a new field for better performance of collection and conversion of solar energy. Nanoparticles and structures are found to enhance light absorption increasing conversion of light to electricity and provide storage and transport for thermal energy (Nano.gov). One of the breakthroughs in solar energy using nanotechnology is the use of MEG or multiple exciton generations. It includes multiple electrons or excitons produced during absorption of photons in semiconductor nanocrystals. Excitons are produced in nanocrystals where energy is conserved due to low threshold photon energy used. MEG is found to work effectively with materials such as PbSe, PbS, PbTe, CdSe, and InAs nanocrystals. Since it is measured in nanocrystals, there is no need or bulk semiconductors to convert energy into electricity. It is a promising way to increase conversion of solar energy into single-celled photovoltaic cells. This breakthrough in technology is found to use Silicon for photovoltaic cells. Silicon is exceedingly abundant in nature and poses no threat to the environment (Beard, et al.). Impact of Solar Energy to the Economy The primary contribution of the Solar Energy is the decrease of oil and gas importation cost. The use of renewable energy proves to be economically beneficial as the country does not depend entirely from the oil and gas importations coming from the Middle East and other oil producing countries. The applications of the solar panels in home installations are also contributing to the reduction of costs for domestic homes. The electrical bills for houses and businesses are lowered down since electricity coming from the installed solar panels contributes to the electricity source. The savings of every American home, when they have the solar panel installed, can be used for other commodity costs and basic needs. The Solar energy elevates the quality of living of people since they can gain big savings and lesser expenses (Solar Energy World). PEAK ENERGY SAVINGS Photovoltaics converts direct sunlight into direct usable electricity. A clean energy source uses the renewable and unlimited energy of the sun. Photovoltaics installed in gymnasiums are no longer a new thing. In fact, many gymnasiums all over the world have installations of solar panels in the community gymnasiums to provide electricity for the nearby areas. Their innovation has proven its economic and environment advantage. Their installation in building such as gymnasiums paves way for the combination of energy production with the other primary functionality of the building such as weatherproofing, structural support and thermal collection. In return, there is a substantial cost saving requiring no high value of land consumption and no separate structure dedicated to electricity generation. Furthermore, it directly provides electricity for the building consumption with no need for heavy transmission and distribution requirements. The losses due to distribution and transmission are minimal, and there is a significant reduction of maintenance cost for the building’s utilities. The installation of photovoltaic on the roofs of homes and gymnasiums makes it an integral part of the architectural design. The overall design of the building results to an environmentally friendly, energy efficient, comfortable and esthetically appealing. Hence, the integration of PV cells on the roofs provides more benefits with minimal to nil disadvantages. It paves the way to a more versatile and unique infrastructure. The number of installed PV on gymnasiums is steadily increasing with a number of projects providing wider markets. There are more and more community who chose to have PV cells installed in their areas. The market for the PV power system installations accounts for more than 50% than other forms of solar energy technology such as the grid installations. PV installations significantly contribute to the CO2 emission reductions. They can act as solar breeder that ensures lifetime technology sustainability. It improves the quality of air in its environment displacing other gas emissions generated from other power plants primarily coal power plants. PV contribute to the clean air movement and facilitates the introduction of other clean air technologies such as electric vehicles and others. It promises sustainability and maintenance of energy generation even without the support of the fossil fuels coming mainly from the Middle East. It provides security for industrialized countries not having to depend on oil importations anymore. The many dispersed PV systems installed can feed electricity with independent operations that can be very useful during emergencies and peak seasons of power outages (IEA). In the context of gymnasium, flat roof types of PV are installed. They are roof integrated products that promise optimum performance. The modules are designed for mounting around 10 to 100 cm above the roof level the allow provision or airflow at the back of the modules. Flat roof PV generators provide higher yield of energy as compared with sloped installations. One of its installations is seen in Williams Building located in Boston. The silicon-based PV modules installed on the roof provided 37 kWh of DC and 23 kWp of AC power. In one of Japan/’s gymnasium, metal lined roof has installed PV on the roofs that can blend with the current buildings esthetics. It now provided 150 kWp for the building. Flat roof types of PC help reduce the buildings thermal load. They are mechanically installed on the roof to blend with the current structures incorporating with the watertight layer and insulation system. When they are installed with appropriates spacing, they are ensured of maximum efficiency and lifetime operational functionality (Prasad and Snow). The fixed panels are very low maintenance. In the BCHydro, the fixed panels in its roof supplied electricity for the whole school (Transition Salt Spring). In Tampa, a 97 kW PV system is installed on the roof of the All People’s Life Center in the Sligh Avenue. The installation allows savings of $16,000 in a year allowing around 97.5 tons CO2 reduction and energy cut of around 130,000 kWh. The San Diego Regional Energy Office has installed PV systems around the municipality, which accounts to 1,400kW to 1,700kWh in a year. The New York State Energy Research and Development Authority have PV systems that generate around 1000kWh to 1300kWh. For a 20,000 square foot building with PV installation, it can produce 15.5 kWh per square foot, which is the equivalent reduction of total electricity purchases of about 5%. The program of using renewable energy in Florida resulted in considerable savings for the city of Tallahassee. They installed a 10 kW PV system at their gymnasium and aquatic center. In effect, the city is provided with 14,000 kWh per year. Another PV installed at the Capital Center Office Complex for their solar hot water system. The overall rebates return to the city amounted to $450 (EPA). CONCLUSION The sun proves to be a stable source of energy. It can provide the unlimited source of energy. Man just has to discover how to collect sunlight in the most efficient and economical way. The utilization of renewable energy is the key factor to combat major global problems today such as the energy crises and climate change. The environmental impact of the installation of solar energy power plants is outweighed by the benefits it safeguards the environment and the economy.. Primarily, the source of solar energy never runs out. Thus, the source is inexhaustible. Its effects on the land, water, air, and the ecosystem can be considered negligible. The consideration of the put up of solar energy power plants can pose threats to the environment. However, the challenges of its installation and operation can be resolved through proper management, wildlife adaptation programs, and efficient design. Its application in the domestic homes and gymnasiums has proven its benefits in the economy and environment. There are many benefits it offer to the people where their installations provide the basic need for electricity with zero maintenance costs and lifetime guarantee. Operation of Solar energy is environment-friendly, reducing greenhouse gasses emission to the atmosphere. Its applications provide higher sustainability and are more economical and more environmental friendly. Works Cited Beard, M.C., Knutsen, K.P., Yu, P., Luther J., Song Q., Metzger, W., Ellingson, R., Nozik., A. “Mutiple Exciton Generation in Colloidal Silicon Nanocrystals”. Nano Letters 7(8): 2506-2512. (2007). Web. EDF Energy. “What is Solar Power?”. 2014. Web. EPA. “Clean Energy Strategies for Local Governments”. (2008). Web. ETSAP. “Concentrating Solar Power : Technology Brief”. IEA-ETSAP and IRENA Technology Brief E10. (2013). Web. IEA. “Added Values of Photovoltaic Power Systems”. Report IEA-PVPS T1. (2001). PDF Ipeck. “How the Solar Energy Impacts the Environment”. Solar Energy World. (2014). Web. 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Union of concerned Scientists. (2014). Web USEPA: United States Environmental Protection Agency. “Solar Energy”. 2015. Web http://www.epa.gov/region1/eco/energy/re_solar.html Read More