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Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)最新文献

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Growth kinetics studies of silicon LPE from metal solutions 金属溶液中硅LPE的生长动力学研究
Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC) Pub Date : 1994-12-05 DOI: 10.1109/WCPEC.1994.519956
T. Wang, T.F. Ciszek
{"title":"Growth kinetics studies of silicon LPE from metal solutions","authors":"T. Wang, T.F. Ciszek","doi":"10.1109/WCPEC.1994.519956","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.519956","url":null,"abstract":"Growth kinetics of silicon liquid phase epitaxy (LPE) from metal solutions was studied in pursuit of device-quality layer formation on cast, metallurgical-grade silicon (MG-Si) substrates for solar cells. We report that a mixture of Al and Cu as a solvent for Si enhances solution wetting to the substrate by Al-SiO/sub 2/ reaction, and generates isotropic growth and macroscopically smooth surfaces due to its high solvent power. This solvent system also controls Al incorporation into the layer by proper Al and Cu compositions in the solution. The layer growth rate was calculated with a rough interface/diffusion boundary layer model and was found to be in good agreement with experimental results, indicating only a small boundary layer (/spl sim/0.1 cm) and a silicon diffusivity of /spl sim/2/spl times/10/sup -4/ cm/sup 2//s in the liquid. The thin layer (/spl sim/30 /spl mu/m) grown on the MG-Si substrate has a minority-carrier diffusion length greater than the layer thickness.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82666993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Photovoltaic modules integrated with a metal curtain wall 光伏组件与金属幕墙集成
Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC) Pub Date : 1994-12-05 DOI: 10.1109/WCPEC.1994.520122
M. Yoshino, N. Nakada, T. Mori, K. Yamagishi, S. Yoshida, Y. Higashi, K. Shirasawa
{"title":"Photovoltaic modules integrated with a metal curtain wall","authors":"M. Yoshino, N. Nakada, T. Mori, K. Yamagishi, S. Yoshida, Y. Higashi, K. Shirasawa","doi":"10.1109/WCPEC.1994.520122","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520122","url":null,"abstract":"An integrated photovoltaic system for buildings has many advantages. To realize building integration of photovoltaics, we have initially designed a PV module integrated with a metal curtain wall. PV modules are installed as spandrel panels and consist of long and slender PV sub-modules. These sub-modules have an encapsulated structure consisting of: glass, EVA, solar cells, EVA, and aluminum base plate. We also present initial PV performance data from the experimental wall. In this wall, almost the same maximum P/sub max/ of 64 W/m/sup 2/ was obtained and the module temperature was approximately 10/spl deg/C lower compared with conventional superstrate-type PV modules which have 1.3 times the solar cells of this module. Moreover, aesthetic requirements for this module are discussed.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82752686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 10
Least cost analysis of renewable energy projects 可再生能源项目的最低成本分析
Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC) Pub Date : 1994-12-05 DOI: 10.1109/WCPEC.1994.521706
M. Cosgrove-Davies, A. Cabraal
{"title":"Least cost analysis of renewable energy projects","authors":"M. Cosgrove-Davies, A. Cabraal","doi":"10.1109/WCPEC.1994.521706","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.521706","url":null,"abstract":"This paper describes the methodology for evaluating dispersed and centralized rural energy options on a least cost basis. In defining the load to be served, each supply alternative must provide equivalent levels of service. The village to be served is defined by the number of loads, load density, distance from the nearest power distribution line, and load growth. Appropriate rural energy alternatives are identified and sized to satisfy the defined load. Lastly, a net present value analysis (including capital, installation, O&M, fuel, and replacement costs, etc.) is performed to identify the least cost option. A spreadsheet-based analytical tool developed by the World Bank's Asia Alternative Energy Unit (ASTAE) incorporates this approach and has been applied to compare photovoltaic solar home systems with other rural energy supply options in Indonesia. Load size and load density are found to be the critical factors in choosing between a grid and off-grid solution.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89088189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
Outdoor performance stability and controlled light-soak testing of amorphous silicon multijunction modules at NREL NREL非晶硅多结模块室外性能稳定性及可控光浸测试
Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC) Pub Date : 1994-12-05 DOI: 10.1109/WCPEC.1994.520014
L. Mrig, J. Burdick, W. Luft, B. Kroposki
{"title":"Outdoor performance stability and controlled light-soak testing of amorphous silicon multijunction modules at NREL","authors":"L. Mrig, J. Burdick, W. Luft, B. Kroposki","doi":"10.1109/WCPEC.1994.520014","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520014","url":null,"abstract":"The National Renewable Energy Laboratory (NREL) has been testing amorphous silicon (a-Si) photovoltaic (PV) modules for more than a decade. NREL has been conducting controlled light-soak testing of multijunction a-Si modules to characterize their performance for stability evaluation as well as to benchmark the technology status. Some of the test modules, after controlled light-soak testing, have been installed outdoors. The authors have observed that under outdoor exposure, the modules further degrade in performance, possibly due to lower outdoor temperatures and varying spectra. The paper presents data on the light-induced degradation for the third controlled light-soak test on multijunction a-Si modules as well as outdoor performance data on single- and multijunction modules under prevailing conditions.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90169381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
An analysis of thin film silicon for photovoltaic applications 光伏用薄膜硅的分析
Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC) Pub Date : 1994-12-05 DOI: 10.1109/WCPEC.1994.520515
J. Yi, R. Wallace, B. Jaganathan, X. Gu, K. Etemadi, W. Anderson
{"title":"An analysis of thin film silicon for photovoltaic applications","authors":"J. Yi, R. Wallace, B. Jaganathan, X. Gu, K. Etemadi, W. Anderson","doi":"10.1109/WCPEC.1994.520515","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520515","url":null,"abstract":"a-Si:H solar cells typically exhibit instability due to intrinsic layer degradation and hydrogen movement. An alternative way to circumvent the a-Si:H solar cell problem is to make use of heterostructure type cells (a-Si:H/poly-Si). The objective of this paper is to characterize properties of thin film amorphous and poly-Si aiming at a heterostructure type solar cell. The material characteristics of the as-grown a-Si:H films are compared with those of the anneal treated films. The structural, optical, and electrical properties were investigated. The anneal treatment changed structural properties as well as electrical and optical characteristics of the film. Resistance, capacitance, dielectric constant, refractive index, and light absorption coefficient are reduced with crystallization of the a-Si:H. Mobility, conductivity, and transmittance are increased after crystallization. The poly-Si grain boundary trap type and activation energy were determined by thermally stimulated current (TSC) measurement. Grain boundary trap type and activation energy were detected by the TSC study. Hole traps dominated after high temperature anneal with activation energy of 0.49 eV. The field effect mobility was increased from 1.6/spl times/10/sup -3/ cm/sup 2//V.s for as-grown amorphous silicon to 67 cm/sup 2//V.s for 850/spl deg/C annealed and hydrogen grain boundary passivated poly-Si.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83765460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A new fabrication method for multicrystalline silicon layers on graphite substrates suited for low-cost thin film solar cells 一种适用于低成本薄膜太阳能电池的石墨衬底多晶硅层制备新方法
Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC) Pub Date : 1994-12-05 DOI: 10.1109/WCPEC.1994.520206
M. Pauli, T. Reindl, W. Kruhler, F. Hornberg, J. Muller
{"title":"A new fabrication method for multicrystalline silicon layers on graphite substrates suited for low-cost thin film solar cells","authors":"M. Pauli, T. Reindl, W. Kruhler, F. Hornberg, J. Muller","doi":"10.1109/WCPEC.1994.520206","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520206","url":null,"abstract":"A new method for the fabrication of a columnar, multicrystalline silicon layer on a graphite substrate is presented. This method basically involves three process steps: (1) deposition of a thin (3-5 /spl mu/m) silicon layer; (2) zone melting recrystallization of this layer with a line electron beam as the heat source to form a multicrystalline seed layer; and (3) thickening of the seed layer by high temperature, epitaxial chemical vapour deposition (CVD) to a thickness of 20-40 /spl mu/m. The recrystallization leads to [110][112]-textured silicon seed layers if sufficiently high scan velocities are applied. The degree of deviation from the ideal [110][112]-texture increases with decreasing scan velocity. The doping level of the seed layer is found to be only weakly affected by the zone melting recrystallization. The epitaxial layer grown on top of the seed layer exhibits a columnar grain structure.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88596152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 10
Field experience and comparison of photovoltaic off-grid power systems and reticulated supply 光伏离网电力系统与并网供电的现场经验与比较
Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC) Pub Date : 1994-12-05 DOI: 10.1109/WCPEC.1994.520163
I. MacGill, M. Watt, R. Kaye
{"title":"Field experience and comparison of photovoltaic off-grid power systems and reticulated supply","authors":"I. MacGill, M. Watt, R. Kaye","doi":"10.1109/WCPEC.1994.520163","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520163","url":null,"abstract":"This paper reports the findings of a recent survey of remote area residents concerning their experiences with PV based off-grid power systems and grid supply. Continued advances in off-grid systems would seem to make them an increasingly cost effective and 'grid equivalent' alternative for remote areas. While economic studies of the two supply options have been reported, less is known about other important factors for consumers assessing the viability of off-grid systems. Residents in remote areas were therefore surveyed on their choice of off-grid or grid power, and their experiences with this supply. Findings include the importance of supply quality and reliability for those who chose the grid option. Their experiences, however, suggest that off-grid power is more reliable and of similar quality. Overall, findings support the conclusion that PV-based off-grid power systems are a viable alternative to reticulated supply for remote consumers.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88699160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Optimization of multijunction a-Si:H solar cells using an integrated optical/electrical model 利用集成光/电模型优化多结a-Si:H太阳能电池
Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC) Pub Date : 1994-12-05 DOI: 10.1109/WCPEC.1994.520024
R.E. Rocheleau, M. Vierthaler
{"title":"Optimization of multijunction a-Si:H solar cells using an integrated optical/electrical model","authors":"R.E. Rocheleau, M. Vierthaler","doi":"10.1109/WCPEC.1994.520024","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520024","url":null,"abstract":"An phenomenological model for multijunction amorphous silicon solar cells which integrates a detailed optical model and an equivalent circuit model with a voltage-dependent photocurrent was developed. The model equations accurately describe the light J-V curves for a-Si:H and a-SiGe:H single junction cells using carrier transport properties comparable to values reported in the literature and which agree closely with values derived from quantum efficiency measurements. Closed form expressions for collection efficiency are derived by approximating the carrier generation profile by an exponential distribution. This new model can be used to predict cell behavior with changes in i-layer thickness and bandgap, carrier mobility-lifetime, and illumination. The model has been combined with a powerful multivariable optimization routine to analyze alternative cell designs. The model is described and representative results are presented.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87380531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 5
High-flux solar furnace processing of silicon solar cells 硅太阳能电池的高通量太阳电炉加工
Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC) Pub Date : 1994-12-05 DOI: 10.1109/WCPEC.1994.520186
Y. Tsuo, J. Pitts, M. Landry, C. Bingham, A. Lewandowski, T. Ciszek
{"title":"High-flux solar furnace processing of silicon solar cells","authors":"Y. Tsuo, J. Pitts, M. Landry, C. Bingham, A. Lewandowski, T. Ciszek","doi":"10.1109/WCPEC.1994.520186","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520186","url":null,"abstract":"We used a 10-kW high-flux solar furnace (HFSF) to diffuse the front-surface n/sup +/-p junction and the back-surface p-p/sup +/ junction of single-crystal silicon solar cells in one processing step. We found that all of the HFSF-processed cells have better conversion efficiencies than control cells of identical structures fabricated by conventional furnace diffusion methods. HFSF processing offers several advantages that may contribute to improved solar cell efficiency: (1) it provides a cold-wall process, which reduces contamination; (2) temperature versus time profiles can be precisely controlled; (3) wavelength, intensity, and spatial distribution of the incident solar flux can be controlled and changed rapidly, (4) a number of high-temperature processing steps can be performed simultaneously; and (5) combined quantum and thermal effects may benefit overall cell performance. The HFSF has also been successfully used to texture the surface of silicon wafers and to crystallize a-Si:H thin films on glass.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77315632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 16
Why Li's solar cell concept cannot work 为什么李的太阳能电池概念不能工作
Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC) Pub Date : 1994-12-05 DOI: 10.1109/WCPEC.1994.520216
Z. Kuźnicki
{"title":"Why Li's solar cell concept cannot work","authors":"Z. Kuźnicki","doi":"10.1109/WCPEC.1994.520216","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520216","url":null,"abstract":"The so-called Li cell or junction near local defect (JNLD) layer device founded upon a discontinuous local defected layer (LDL) inserted in the emitter near the p-n junction raised many hopes since its description in May 1992. The next two years were delusive because of many negative results. Why does it not work when the concept of Si modification to enlarge its optical absorption has been known in solar community from the 1970s and the built-in electric field improvement postulated since the 1960s? The main problems are to know which potentially applicable improvements are actually important and then to put the different separately proven phenomena together. It is easier to understand the contradictions of Li's concept by comparing the cell with a well-working structure. Some of the authors' concepts and physical modeling published recently allow this analysis although the two approaches are founded on different principles concerning especially the inserted layer fine structure, the built-in electric field distribution, and the electronic transport in the cell emitter.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91042753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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