...GERMANY 2011 Solar cell generations over 40% efficiency R. R. King*, D. Bhusari, D. Larrabee, X.-Q. Liu, E. Rehder, K. Edmondson, H. Cotal, R. K. Jones, J. H. Ermer, C. M. Fetzer, D. C. Law and N. H. Karam Spectrolab, Inc., 12500 Gladstone Ave, Sylmar, CA 91342, USA ABSTRACT Multijunction III-V concentrator cells of several different types have demonstrated solar conversion efficiency over 40% since 2006, and represent the only third-generation photovoltaic technology to enter commercial power generation markets so far. The next stage of solar cell efficiency improvement, from 40% to 50%-efficient production cells, is perhaps the most important yet, since it is in this range that concentrator photovoltaic (CPV) systems can become the lowest cost option for solar electricity, competing with conventional power generation without government subsidies. The impact of 40% and 50% cell efficiency on cost-effective geographic regions for CPV systems is calculated in the continental US, Europe, and North Africa. We take a systematic look at a progression of multijunction cell architectures that will take us up to 50% efficiency, using modeling grounded in well-characterized solar cell materials systems of today’s 40% cells, discussing the theoretical, materials science, and manufacturing considerations for the most promising approaches. The effects of varying solar spectrum and current balance on energy production in 4-junction, 5-junction, and 6-junction terrestrial concentrator cells are shown...
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...Objective In this experiment, the performance of solar cells under different working conditions are investigated. These variables include light intensity and temperature. This is achieved by studying the different current-voltage characteristic curves. Also, the relationship between short-circuit current and no-load voltage with different working conditions is studied. Introduction Solar Cell A solar cell (or a "photovoltaic" cell, Fig. 1) is a semiconductor device that converts light energy in the form of photons from the sun (solar light) into electricity. Solar cells have many applications and are regarded as one of the key technologies towards a sustainable clean energy supply. [pic] Fig. 1 A solar cell, made from a monocrystalline silicon wafer Silicon solar cell has a structure of a pn junction. Silicon can be doped with tri- and pentavalent atoms to make a p- or n-type semi-conductor. If we put a p-and n-type crystal together we get a junction (pn-junction, Fig. 2) whose electrical properties determine the performance of the solar cell. [pic] Fig. 2 pn-junction in the energy-band diagram. – acceptors, + donors, UD is the diffusion potential, EF is the Fermi characteristic energy level, and e is the elementary charge. Photovoltaic Device Principles Consider a pn junction with a very narrow and more heavily doped n-region, in equilibrium (with no external voltage) the Fermi characteristic energy level EF will be the same throughout. Because of the difference...
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...PHOTOSYNTHESIS AND SOLAR CELLS 1 The Comparison of Photosynthesis and Solar Cells THE COMPARISON OF PHOTOSYNTHESIS AND SOLAR CELLS 2 Abstract This paper will compare and contrast photosynthesis and the semiconductor based solar cell. This will be accomplished by detailing three similarities, and three differences between the two. The first of the similarities being the absorption of solar energy, the second being the transformation of solar energy into a different more useable form of energy, and finally the third being that they both use organic colorants to attract the sun’s rays. The three differences being that one produces chemical energy and the other electrical energy. The second difference is that one occurs naturally and the other is manmade, and the third difference is that one is cost effective and the other are expensive to produce. This paper will also describe how the laws of thermodynamics apply to each of the systems, giving the reader even further insight on the topic at hand. THE COMPARISON OF PHOTOSYNTHESIS AND SOLAR CELLS 3 The Comparison of Photosynthesis and Solar Cells Photosynthesis is the process in green plants and other organisms by which carbohydrates are synthesized from carbon dioxide and water using light as an energy source. Semi-conductor based solar cells, also known...
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...Int. J. Electrochem. Sci., 8 (2013) 6734 - 6743 International Journal of ELECTROCHEMICAL SCIENCE www.electrochemsci.org Natural Dye Extracted from Rhododendron Species Flowers as a Photosensitizer in Dye Sensitized Solar Cell Hee-Je Kim1, Yeo-Tae Bin1, S.N. Karthick1, K.V. Hemalatha*,1, C. Justin Raj1, S.Venkatesan2, Songyi Park1, G. Vijayakumar3 1 School of Electrical Engineering, Pusan National University, Jangjeon, Geumjeong, Busan 609-735, Republic of Korea. 2 Measurements Laboratory, Gujarat Tea Processors and Packers Ltd., Khokhra, Ahmadabad-380008, Gujarat, India 3 Department of Chemistry, RVS Faculty of Engineering, Affiliated to Anna university, Coimbatore, India * E-mail: hemaac@gmail.com Received: 7 February 2013 / Accepted: 4 April 2013 / Published: 1 May 2013 The natural dye, anthocyanin, was extracted from the flowers of Rhododendron species with three different colors, pink, red and violet, using a simple extraction technique, and was used as the sensitizer in dye-sensitized solar cells. The dyes were treated with nitric and acetic acids to examine their effects on the power conversion efficiency. According to the experimental results, the performance was better with the acetic acid-treated anthocyanin. The Jsc value for the acetic acidtreated pink, red and violet dyes increased to 0.887, 0.932 and 0.737 mA/cm2 compared to nitric acid treated and bare dye. The conversion efficiency of the acetic acid-treated pink, red and violet was 0.35%, 0.36%,...
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...to solve the issue, people must cut short electricity use and increase power input. It means that devices should be off when they are not in use, replace obsolete bulbs with energy efficient bulbs and at the same time build more energy harvest systems to enhance electricity production. Electrical energy can be produced by renewable sources and non-renewable sources of energy. With development in the technological field, renewable resources like water, solar, and wind current are preferred to produce electricity in order to replace fossil fuel which would not last very long. In fact, natural resources can produce multi-folds of electricity without being eradicated. However, this essay is comparing solar panel to wind turbine. Their major differences are location, method and efficiency. Initially, the difference of both solar panel and wind turbine is method of generating electricity. Since the solar panel has defined as an object that absorbed the sunlight and turns it into electricity. The method to generate electricity by solar panel is complex. Firstly, after the sunlight shines into the panel, it has been converted from protons to electrons (Llorens, n.d.). After that, the current’s output is in a form of direct current. This is a type of electrical current which flows in one direction in a circuit and mostly loss energy when energy is carried over a long distance (“Alternating Current,”n.d.). However, the current of electricity that people use in the...
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...many similarities and also many differences when comparing photosynthesis and semiconductor based solar cells this paper will outline those these as well as give a description of the two cycles. I will also be defining the law of thermodynamics and explaining how it applies to photosynthesis and also semiconductor based solar cells harnessing solar energy. Photosynthesis is the process of converting solar energy into chemical energy in the form of carbohydrates. For photosynthesis to occur a few factors must be present such as water, carbon dioxide, chlorophyll, and light energy. Photosynthesis consists of two sets of reactions the first being the photo portion or light reaction which is the reaction that captures solar energy the second being the synthesis reaction or Calvin cycle reactions which converts that solar energy into carbohydrates (Mader, 2010). For light reactions to occur first light energy enters the cells and is absorbed by the chlorophyll. That Light energy raises the energy level chlorophyll enabling electrons to be freed form the chlorophyll molecules. This makes the chlorophyll molecules positively charged the electrons from hydrogen atoms are attracted to the positively chlorophyll causing water molecules to break apart into oxygen atoms. The elections freed from the chlorophyll and the protons freed from water take part in the chemical reactions in the cell. The reactions result in the production of adenosine triphosphate (ATP) and nicotinamide adenine...
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...有机太阳能电池原理与应用 何游 刘世卓 许德安 张昱 (South University of Science and Technology of China) 摘要： 有机半导体材料以其原料易得，廉价，制备 工艺简单，环境稳定性高，可折叠，有良好的光 伏效应等优点，日益被人们所重视。本文首先介 绍了有机太阳能电池的分类、结构及基本原理， 之后评述了有机太阳能电池的应用，并对它的未 来发展前景作了展望。 1.引言 1.1 有机太阳能电池背景 随着煤炭、石油、天然气等化石燃料的大量使用，对全球环境造成了不可忽视的污 染，排放二氧化碳、甲烷等温室气体也造成了全球气候变化，更加棘手的是上述等不可 再生能源的数量是有限的，随着时间的推移和消耗量的剧增，能源危机成为人类不得不 面对的严峻问题之一。 而太阳能是取之不尽用之不竭的绿色新能源， 太阳能的广泛应用为能源问题带来一 丝曙光。利用太阳能必须依赖于光伏电池，而有机光伏电池又是其中很重要的一部分。 本文将针对有机太阳能电池的分类、结构、原理、局限以及发展前景展开评论。 太阳能电池又称为“太阳能芯片”或“光电池” “，是一种利用太阳光直接发电的 光电半导体薄片。它只要被光照到，瞬间就可输出电压及电流。在物理学上称为太阳能 光伏（Photovoltaic，photo 光，voltaic 伏特，缩写为 PV） ，简称光伏。 1839 年， 1883 年 Charles 光生伏打效应第一次由法国物理学家 A.E.Becquerel 发现。 Fritts 制造了第一块太阳电池。Charles 用硒半导体上覆上一层极薄的金层形成半导体金 属结，该器件只有 1%的效率。1970 年代，由于能源危机，世界各国开始关注能源开发 1973 年发生了石油危机， 的重要性。 人们开始把太阳能电池的应用转移到一般的民生用 途上。 1.2 有机太阳能电池分类 1.2.1 单层有机太阳能电池 单层有机太阳能电池是有机太阳能电池中最简单的形式， 两个金属导电层夹着有机 电子材料层，例如高功函的氧化铟锡(ITO)和低功函的铝、镁和钙。 两个导电层的功函差在有机层的两端建立了一个电场。当有机层吸收小光子后， 电 子会被激发到 LUMO 上，空穴留在 HOMO 上形成激子，而电极上不同的功函造成的电 势有利于激子的分离，将电子拉到正极，空穴拉到负极，这个过程中形成的电压和电流 就可以被利用。电场并不是最好的使激子分离的方法，异质结电池中使用有效场来使激 子分离的效率更高。 1.2.2 双层太阳能电池 这类电池在电极间有两层不同的物质，这两种物质在电子亲和性、电离能方面有差 异，因此静电力在两层间的界面产生。这两层所用的材料要尽可能使这两种差异更大， 从而使得局部电场大到足以使激子分离，比单层太阳能电池更有效。两种材料中拥有较 高电子亲和性和电离能的是电子受体，另外一个是电子给体。这种结构也叫做平面给受 异质结。 1.2.3 本体异质结太阳能电池 在本体异质结太阳能电池中，电子给体与受体共混到一起形成膜。每块给体或受体 的长度与激子扩散距离一致，给体或受体中产生的大部分激子可以到达两个物质的界 面，并得到有效的分离。电子迁移到受体区域后逐渐到达电极并被收集，空穴被拉到相 反的方向，并被另一个电极所收集。 2.有机光伏电池结构 2.1 有机光伏电池原理 太阳能电池是一个特别的半导体二极管，它可能将可见光能转化为直流电，一些 太阳能电池可能转化红外和紫外光的能量为直流电。 通常用于有机光伏电池的材料都是 有大量共轭键的，共轭键是由交替碳碳单键和双键组成的，共轭键的电子的简并轨道是...
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...Running head: PHOTOSYNTHESIS VS. SEMICONDUCTOR BASED SOLAR CELL Photosynthesis Vs. Semiconductor Based Solar Cell Biology – SCI 115 23 January 2012 Abstract This paper discusses photosynthesis and how it is used by plants to harness solar energy. It also discusses semiconductor-based solar cells and how they are able to harness solar energy and convert it to electricity. This paper also compares the two types of solar energy systems and provides an overview of how the two systems are alike and how they are different. In closing, this paper will briefly explain how the laws of thermodynamics apply to each of the two energy systems. Photosynthesis Photosynthesis is a process that transfers solar energy, or energy from the sun, into a chemical energy that provides nutrients to plants and animals all over the world. Without these important nutrients, plants, animals and humans would not be able to survive on earth. “Animals and plants get energy by metabolizing nutrient molecules made by photosynthesizers.” (Mader, 2010) Semiconductor-Based Solar Cell Before discussing what a semiconductor-based solar cell is, I would first like to define a semiconductor and then explain how it is used in a solar cell type environment. A semiconductor is, “a class of materials, such as silicon and germanium, whose electrical properties lie between those of conductors (such as copper and aluminum) and insulators (such as glass and rubber)...
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...How the Angle of a Solar Cell effects the Voltage Produced Introduction: In this experiment, I will be experimenting the effect of adjusting the angle of a solar cell relative to the direction of light and the voltage produced based on the angle change. Factors: Some of the possible factors that could affect my experiment are * ------------------------------------------------- The angle of the solar cell. * ------------------------------------------------- The distance of the solar cell from the light source. * ------------------------------------------------- The intensity of the light source. I will change the angle of the solar cell and use this as my independent variable, going up in 5 increments and measuring the voltage produced at each different angle. Hypothesis: I predict that as if I increase the angle of the solar cell from 0 (at horizontal) to 90 (vertical) the voltage produced would also increase per angle increment. Solar cells are able to generate a flow of electricity due to the photoelectric effect, which states that, when photons hit the surface of a metal they transfer their kinetic energy to an electron, if this energy is enough to overcome the attraction between the nucleus of the atom and the electron, the electron is freed from the atom which allows it to generate a flow or current. The energy of a photon is proportional to its frequency due to the E=hf relationship, so the higher frequency of the light the more energy the photons...
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...PV StatuS RePoRt EUR 24807 EN - 2011 The Institute for Energy provides scientific and technical support for the conception, development, implementation and monitoring of community policies related to energy. Special emphasis is given to the security of energy supply and to sustainable and safe energy production. European Commission Joint Research Centre Institute for Energy Contact information Address: Via Enrico Fermi 2749 TP 450 21027 Ispra (VA) Italy E-mail: arnulf.jaeger-waldau@ec.europa.eu Tel.: +39 0332 789119 Fax: +39 0332 789268 http://ie.jrc.ec.europa.eu www.jrc.ec.europa.eu PV Status Report 2011 Research, Solar Cell Production and Market Implementation of Photovoltaics July 2011 Arnulf Jäger-Waldau European Commission, DG Joint Research Centre, Institute for Energy, Renewable Energy Unit Via Enrico Fermi 2749; TP 450 I – 21027 Ispra (VA), Italia EUR 24807 EN Legal notice Neither the European Commission nor any person acting on behalf of the Commission is responsible for the use, which might be made of the following information. The report does not represent any official position of the European Commission, nor do its contents prejudge any future Commission proposals in any areas of Community policy. A great deal of additional information on the European Union is available on the Internet. It can be accessed through the Europa server http://europa.eu/ JRC 64900 EUR 24807 EN ISBN 978-92-79-20171-4 ISSN 1831-4155 doi 10.2788/87966 The report...
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...Case Study of Solar Cells Solar cells or photovoltaic cells are a renewable source of electricity, harnessed from sunlight and thermal energy derived from the sun. It doesn’t emit any greenhouse gases (sulphur dioxide and carbon monoxide) when producing electricity. During a sunny and clear day, sun rays can provide over a 1000 watts of energy per square meter of the planet’s surface. Photovoltaic cells are made of semi conductive material such as silicon. As the light ray hits the solar cell, a fraction of the light is absorbed within the semi conductive material. The energy from the light knocks electrons loose causing them to collide, becoming delocalised. Solar cells can be used as a partial or entire source for energy, it allows the consumer to reduce energy costs and save money, the only issue being that due to installation costs, the payback time for solar power could be several years. Photovoltaic cells use a single junction to create an electric field within the semi conductive silicone. Within a single junction Photovoltaic cell, only the photons which an equal amount of energy or greater than the band gap (energy range in solid material where no exist) of the material can delocalise an electron to for an electric circuit. To convert more energy from the photons, more solar cells are used to create plural band gaps and junctions. Devices with multiple junctions (tandem cells) have a higher conversion efficiency, wasting less energy in the process, due to a converting...
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...Solar Energy Materials & Solar Cells 94 (2010) 1553–1571 Contents lists available at ScienceDirect Solar Energy Materials & Solar Cells journal homepage: www.elsevier.com/locate/solmat Review Business, market and intellectual property analysis of polymer solar cells Torben D. Nielsen a, Craig Cruickshank b, Søren Foged c, Jesper Thorsen c, Frederik C. Krebs a,n a b c Risø National Laboratory for Sustainable Energy, Technical University of Denmark, Frederiksborgvej 399, DK-4000 Roskilde, Denmark Cintelliq Ltd., St. John’s Innovation Centre, Cowley Road, Cambridge CB4 0WS, UK ´ Inspicos A/S, Kogle Alle 2, 2970 Hørsholm, Denmark a r t i c l e in fo Article history: Received 5 February 2010 Received in revised form 11 April 2010 Accepted 20 April 2010 Available online 8 May 2010 Keywords: Business analysis Market analysis IPR analysis Intellectual property analysis Polymer solar cells Organic solar cells OPV Roll-to-roll processing Polymer solar cell modules Patents abstract The business potential of polymer solar cells is reviewed and the market opportunities analyzed on the basis of the currently reported and projected performance and manufacturing cost of polymer solar cells. Possible new market areas are identified and described. An overview of the present patent and intellectual property situation is also given and a patent map of polymer solar cells is drawn in a European context. It is found that the business potential of polymer solar cells is large...
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...Solar and Plant Cells Compared Tiffany L. Triggs Strayer University The Importance of Energy For plant Earth, the Sun is the main source for all energy. It is the main essential thing that provides us with light, warmth and energy. Some organisms, such as plants and algae, create their own food using the sun as their main source of energy. In turn the fuel the rest of the world by creating energy for animals and humans after being consumed. They also remove carbon dioxide from the air and replenish oxygen for us to breath. This process, through which this energy is harnessed and used to create food, or carbohydrates, is called photosynthesis. Can the energy of the sun be harnessed by humans to create energy? It can be and it is through the use of solar cells. Photosynthesis and solar cells are similar, yet different in a few ways. Creating Our Own Energy Humans have figured out how to use the power of the sun for energy. Using Solar panels containing semiconductors, we can turn the sun into electricity, a very popular form of energy. In this way, photosynthesis and solar cells are similar, both using the suns light to create a form of energy. The type of energy created, however, is where one difference comes into play. Plants create a chemical energy known as carbohydrates, a simple organic compound of oxygen, carbon and hydrogen, while solar cells use semiconductors to produce electricity. Use of Electrons Solar Cells and Photosynthesis both use a form...
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...Plant Cell versus Solar Cell Katrina Minchew July 18, 2011 Strayer University | | Photosynthesis is defined as the process in which green plants and other organisms by which carbohydrates are synthesized from carbon dioxide and water using light as an energy source. It takes place mainly inside the leaves. This process utilizes light energy and it is transformed into chemical energy used to create organic compounds. Photosynthesis consists of two processes that use both light and dark energy. The first process, light reaction transforms light into energy. The second process utilizes dark reactions, use the energy and carbon dioxide to produce sugar. The process needs sunlight, water, and carbon dioxide. These materials are transported through the leaves. Water is absorbed by the plant through the roots and is then delivered to the leaves through the plant tissue. The carbon dioxide is absorbed through small holes in plant leaves known as stomata. It also releases oxygen. The process known as chlorophyll is when the green pigment of plants and photosynthetic algae and bacteria trap the energy of sunlight. In plants, photosynthesis takes place inside the chloroplasts, which is the organelle that carries out photosynthesis and starch grain formation. A chlorophyll-containing organelle in plants is the site of photosynthesis. A solar cell also known as the photovoltaic cell is a solid state electrical mechanism that converts the energy of light directly into electricity...
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...Semi-conductor based solar cells and Photosynthesis has many qualities that are in common. Plants receive sunlight from contact (light reaction). A photovoltaic (PV) panel provides sunlight to the solar cells. Similar to how sunlight helps produce chlorophyll in plants, semiconducting material absorbs sunlight. (Oppapers.com). Because of their outputs, photosynthesis and semi-conductor solar cells have great value.. In order to create food, plants absorb sunlight and create oxygen. While this process takes place, plants use sunlight and carbon dioxide to convert water molecules into hydrogen, oxygen, and electrons (Oppapers.com). The light reaction of photosynthesis can be easily compared to how electricity is created with solar cells. The electrons that are in the solar cell get energy from the sun; from that point they are converted to a high energy level. After being turned into a high energy level, they are then accepted by the wire to run the semi-conductor motor. These processes are similar because they both lose electrons. In solar cells electrons are replenished when the electrical circuit is complete and in plant cells, splitting water furnishes more electrons (Johnson, S.). Although they have similarities, they are also very different. Plants have a more difficult time at absorbing sunlight than solar cells. Plants have the responsibility of providing energy to live on, whereas solar cells only have to provide electricity for a wire. It is very important...
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