晶硅太阳能电池组件—背板材料产品技术原材料测试方法及质量问题.pdf

Chemical treatment of crystalline silicon solar cells as a method of recovering pure silicon from photovoltaic modulesRenewable Energy Photovoltaic technology is used worldwide to provide reliable and cost-effective electricity for industrial, commercial, residential and community applications. The average lifetime of PV modules can be expected to be more than 25 years. The disposal of PV systems will become a problem in view of the continually increasing production of PV modules. These can be recycled for about the same cost as their disposal. Photovoltaic modules in crystalline silicon solar cells are made from the following elements, in order of mass: glass, aluminium frame, EVA copolymer transparent hermetising layer, photovoltaic cells, installation box, Tedlar ? protective foil and assembly bolts. From an economic point of view, taking into account the price and supply level, pure silicon, which can be recycled from PV cells, is the most valuable construction material used. Recovering pure silicon from damaged or end-of-life PV modules can lead to economic and environmental benefits. Because of the high quality requirement for the recovered silicon, chemical processing is the most important stage of the recycling process. The chemical treatment conditions need to be precisely adjusted in order to achieve the required purity level of the recovered silicon. For PV systems based on crystalline silicon, a series of etching processes was carried out as follows: etching of electric connectors, anti-reflective coating and n-p junction. The chemistry of etching solutions was individually adjusted for the different silicon cell types. Efforts were made to formulate a universal composition for the etching solution. The principal task at this point was to optimise the etching temperature, time and alkali concentration in such a way that only as much silicon was removed as necessary. Engineering, institutions, and the public interest: Evaluating product quality in the Kenyan solar photovoltaics industryEnergy Policy Solar sales in Kenya are among the highest per capita among developing countries. While this commercial success makes the Kenya market a global leader, product quality problems have been a persistent concern. In this paper, we report performance test results from 2004 to 2005 for five brands of amorphous silicon (a-Si) photovoltaic (PV) modules sold in the Kenya market. Three of the five brands performed well, but two performed well below their advertised levels. These results support previous work indicating that high-quality a-Si PV modules are a good economic value. The presence of the low performing brands, however, confirms a need for market institutions that ensure the quality of all products sold in the market. Prior work from 1999 indicated a similar quality pattern among brands. This confirms the persistent nature of the problem, and the need for vigilant, long-term approaches to quality assurance for solar markets in Kenya and elsewhere. Following the release of our 2004/2005 test results in Kenya, the Kenya Bureau of Standards moved to implement and enforce performance standards for both amorphous and crystalline silicon PV modules. This appears to represent a positive step towards the institutionalization of quality assurance for products in the Kenya solar market. Electrical performance results from physical stress testing of commercial PV modules to the IEC 61215 test sequenceSolar Energy Materials and Solar Cells This paper presents statistical analysis of the behaviour of the electrical performance of commercial crystalline silicon photovoltaic (PV) modules tested in the Solar Test Installation of the European Commission s Joint Research Centre from 1990 up to 2006 to the IEC Standard 61215 and its direct predecessor CEC Specification 503. A strong correlation between different test results was not observed, indicating that the standard is a set of different, generally independent stress factors. The results confirm the appropriateness of the testing scheme to reveal different module design problems related rather to the production quality control than material weakness in commercial PV modules. Efficiency model for photovoltaic modules and demonstration of its application to energy yield estimationA new method has been proposed [W. Durisch, K.H. Lam, J. Close, Behaviour of a copper indium gallium diselenide module under real operating conditions, in: Proceedings of the World Renewable Energy Congress VII, Pergamon Press, Oxford, Elsevier, Amsterdam, 2002, ISBN 0-08-044079-7] for the calculation of the annual yield of photovoltaic (PV) modules at selected sites, using site-specific meteorological data. These yields are indispensable for calculating the expected cost of electricity generation for different modules, thus allowing the type of module to be selected with the highest yield-to-cost ratio for a specific installation site. The efficiency model developed and used for calculating the yields takes three independent variables into account: cell temperature, solar irradiance and relative air mass. Open parameters of the model for a selected module are obtained from current/voltage ( I/V) characteristics, measured outdoors at Paul Scherrer Institute s test facility under real operating conditions. From the model, cell and module efficiencies can be calculated under all relevant operating conditions. Yield calculations were performed for five commercial modules (BP Solar BP 585 F, Kyocera LA361K54S, Uni-Solar UPM-US-30, Siemens CIS ST40 and Wuerth WS11003) for a sunny site in Jordan (Al Qawairah) for which reliable measured meteorological data are available. These represent mono-crystalline, poly-crystalline and amorphous silicon as well as with copper – indium-diselenide, CuInSe 2 PV modules. The annual yield for these modules will be presented and discussed. Experimental validation of crystalline silicon solar cells recycling by thermal and chemical methodsIn recent years, photovoltaic power generation systems have been gaining unprecedented attention as an environmentally beneficial method for solving the energy problem. From the economic point of view pure silicon, which can be recovered from spent cells, is the most important material owing to its cost and limited supply. The article presents a chemical method for recycling spent or damaged modules and cells, and the results of its experimental validation. The recycling of PV cells consists of two main steps: the separation of cells and their refinement. Cells are first separated thermally or chemically; the separated cells are then refined. During this process the antireflection, metal coating and p – n junction layers are removed in order to recover the silicon base, ready for its next use. This refinement step was performed using an optimised chemical method. Silicon wafers were examined with an environmental scanning electron microscope (ESEM) coupled to an EDX spectrometer. The silicon wafers were used for producing new silicon solar cells, which were then examined and characterized with internal spectral response and current – voltage characteristics. The new cells, despite the fact that they have no SiN x antireflective coating, have a very good efficiency of 13 – 15%. The impact of silicon feedstock on the PV module costThe impact of the use of new (solar grade) silicon feedstock materials on the manufacturing cost of wafer-based crystalline silicon photovoltaic modules is analyzed considering effects of material cost, efficiency of utilisation, and quality. Calculations based on data provided by European industry partners are presented for a baseline manufacturing technology and for four advanced wafer silicon technologies which may be ready for industrial implementation in the near future. Iso-cost curves show the technology parameter combinations that yield a constant total module cost for varying feedstock cost, silicon utilisation, and cell efficiency. A large variation of feedstock cost for different production processes, from near semiconductor grade Si (30 ?/kg) to upgraded metallurgical grade Si (10 ?/kg), changes the cost ofcrystalline silicon modules by 11% for present module technologies or by 7% for advanced technologies, if the cell efficiency can be maintained. However, this cost advantage is completely lost if cell efficiency is reduced, due to quality degradation, by an absolute 1.7% for present module technology or by an absolute 1.3% for advanced technologies.Thin-film monocrystalline-silicon solar cells made by a seed layer approach on glass-ceramic substratesSolar modules made from thin-film crystalline-silicon layers of high quality on glass substrates could lower the price of photovoltaic electricity substantially. One way to create crystalline-silicon thin films on non-silicon substrates is to use the so- called “ seed layer approach ” , in which a thin crystalline-silicon seed layer is first created, followed by epitaxial thickening of this seed layer. In this paper, we present the first solar cell results obtained on 10- μm -thick monocrystalline-silicon (mono-Si) layers obtained by a seed layer approach on transparent glass-ceramic substrates. The seed layers were made using implant-induced separation and anodic bonding. These layers were then epitaxially thickened by thermal CVD. Simple solar cell structures without integrated light trapping features showed efficiencies of up to 7.5%. Compared to polycrystalline-silicon layers made by aluminum-induced crystallization of amorphous silicon and thermal CVD, the mono-Si layers have a much higher bulk diffusion lifetime. Waved glass: Towards optimal light distribution on solar cell surfaces for high efficient modulesA method to improve the module efficiency of solar cells by modifying the surface of the glass cover of the solar cells module is proposed. A model is built to show that a better efficiency can be achieved by optimizing the light distribution on the cell, which reduces the shadow losses and thereby allows the finger spacing to be decreased, which in turn decreases the (resistive) ohmic losses. This method is illustrated by considering industrial crystalline silicon solar cells as an example, however, it applies to all solar cells that are characterized by a metallization pattern on the surface of the solar cell. It is estimated that this method can improve the relative module efficiency by about 5% and halve the front side losses. Analysis of series resistance of crystalline silicon solar cell with two-layer front metallization based on light-induced platingImproving the front metallization quality of silicon solar cells should be a key to enhance cell performance. In this work, we investigated a two-layer metallization scheme involving light-induced plating (LIP) and tried to quantify its impact on the series resistance of the front grid metals and FFs on finished cells. To estimate the effect of LIP processing on a printed and fired seed layer, individual components of series resistance were measured before and after LIP processing. Among them, grid resistance and contact resistance were closely observed because of their large contribution to series resistance. To optimize the plating on the seed metal grid, the grid resistance of the two-layer metal grid structure was calculated as a function of cross section area of the plated layer. Contact resistivity of the grid before and after LIP processing was analyzed to understand the contact resistance reduction, as well. As a result, the efficiency of solar cells with 80 μ m seed metal grid width increased by 0.3% absolute compared with conventional solar cells of 120 μ m metal grid width. The total area of electrodes in conventional cells was 1800 mm 2 and electrodes area of LIP processed solar cells was 1400 mm 2. The efficiency gain was due to reduction of shadowing loss from 7.7% to 6.0% without the increase of resistance due to two-layer front metallization. Simulation of hetero-junction silicon solar cells with AMPS-1DMono- and poly-crystalline silicon solar cell modules currently represent between 80% and 90% of the PV world market. The reasons are the stability, robustness and reliability of this kind of solar cells as compared to those of emerging technologies. Then, in the mid-term, silicon solar cells will continue playing an important role for their massive terrestrial application. One important approach is the development of silicon solar cells processed at low temperatures (less than 300 ° C) by depositing amorphous silicon layers with the purpose of passivating the silicon surface, and avoiding the degradation suffered by silicon when processed at temperatures above 800 °C. This kind of solar cells is known as HIT cells (hetero-junction with an intrinsic thin amorphous layer) and are already produced commercially (Sanyo Ltd.), reaching efficiencies above 20%. In this work, HIT solar cells are simulated by means of AMPS-1D, which is a program developed at Pennsylvania State University. We shall discuss the modifications required by AMPS-1D for simulating this kind of structures since this program explicitly does not take into account interfaces with high interfacial density of states as occurs at amorphous-crystalline silicon hetero-junctions. 太阳能硅电池的软件仿真设计与制造Mapping the performance of PV modules, effects of module type and data averaging统计实验与数据收集处理：太阳能发电电池背板组件模块的效用与背板材料开发方向选取Solar Energy A method is presented for estimating the energy yield of photovoltaic (PV) modules at arbitrary locations in a large geographical area. The method applies a mathematical model for the energy performance of PV modules as a function of in-plane irradiance and module temperature and combines this with solar irradiation estimates from satellite data and ambient temperature values from ground station measurements. The method is applied to three different PV technologies: crystalline silicon, CuInSe 2 and CdTe based thin-film technology in order to map their performance in fixed installations across most of Europe and to identify and quantify regional performance factors. It is found that there is a clear technology dependence of the geographical variation in PV performance. It is also shown that using long-term average values of irradiance and temperature leads to a systematic positive bias in the results of up to 3%. It is suggested to use joint probability density functions of temperature and irradiance to overcome this bias. Outdoor performance evaluation of photovoltaic modules using contour plots户外太阳能电池背板发电效果 /转化率评估评价Current Applied PhysicsThe impact of environmental parameters on different types of Si-based photovoltaic (PV) modules (single crystalline Si (sc-Si), amorphous Si (a-Si) and a- Si/ microcrystalline Si ( μc -Si)) which have different spectral responses were characterized using contour plots. The contour plots of PV performance as a function of module temperature and spectral irradi