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S. Canada L. Moore H. Post J. Strachan 《Progress in Photovoltaics: Research and Applications》2005,13(1):67-74
The field performance of photovoltaic systems has been studied extensively for many applications and a number of databases exist in the United States and internationally. However, these databases focus almost exclusively on the system elecrical performance. Published information on the operation and maintenance (O&M) experience and costs for photovoltaic systems is almost nonexistent. At a time when photovoltaics is being considered as a viable option for distributed energy generation, it is critical that maintenance experience be captured to identify lifecycle costs and/or levelized energy costs for these systems, as well as to identify areas for system and component improvements. This paper addresses the data collection, analysis and results of an off‐grid residential customer service program offered by the Arizona Public Service (APS) Company over a six‐year period from 1997 through 2002. Standardized, packaged photovoltaic systems were offered and operated by APS through a lease arrangement with customers throughout the state of Arizona. The operation and maintenance records for these systems were carefully tracked and analyzed. The O&M costs, database development, cost drivers, lifecycle cost implications, and lessons learned are presented and discussed. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Luis Miguel Carrasco Luis Narvarte Ana Peral Manuel Vzquez 《Progress in Photovoltaics: Research and Applications》2013,21(5):1136-1145
In this paper, a reliability analysis of a photovoltaic rural electrification (PVRE) programme is proposed considering the failures in the 13 000 installed Solar Home System (SHS) devices occurring over a long operating period of 5 years. A previous arrangement of the database and a brief explanation of the reliability concepts will serve to introduce the failure distribution of every component, from which the SHS lifetime operating features will be described. An application example will show the usefulness of the obtained results in the forecasting of spare parts during the maintenance period. The conclusions of this study may be useful in the scientific design of PVRE programme maintenance structures, with the goal of shedding some light on the technical management mechanisms in decentralised rural electrification. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Prabakar Loka Sudir Moola Karthik Polsani Shekar Reddy Shannon Fulton Andrew Skumanich 《Progress in Photovoltaics: Research and Applications》2014,22(7):733-743
Micro‐grids in developing countries present a significant application opportunity for photovoltaics (PV) as an energy‐enabling technology. The authors project 10 GW for this application in the next decade. The growth of this sector will be enhanced by shared learning of the best practices. The authors are part of a team that successfully installed 1/3 MW in micro‐grids and presented the lessons learned and a useful methodology for determining key metrics. The PV is part of the rural electrification in India and is representative of current global PV micro‐grids. This project provides basic lighting and electricity for 57 villages in Visakhapatnam in India. The project was carried out with a goal of optimizing power against cost. Various metrics are presented: costs, time, operations and maintenance, and performance. Also discussed are implementation strategies for cost containment, stakeholder considerations, and post‐install support and user payment collection. Learning points are presented on project execution, engagement of local people, and challenges addressed. The aspect of demand capacity level (hours of availability) is examined in more detail, with modeling being performed to identify an optimal approach to increasing the level given the cost constraints. The combination of real data and modeling is a useful approach for PV and micro‐grid optimization. This case study quantitatively supports the value of the use of PV for rural electrification. Beyond this example in India, where the federal government is planning an increase to more than 2000 sites, there is a significant opportunity for PV in the global micro‐grid electrification context. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Hongyuan Xiao Yufeng Wang Nan Jiao Yiping Guo Wen Dong Hua Zhou Qian Li Chengjun Sun 《Advanced Electronic Materials》2019,5(10)
Recently, the visible or even‐to‐near‐infrared light absorbing perovskite ABO3 solid state solutions, show promising application in solar cells and multienergy harvesters or sensors by simultaneously introducing transition metal and oxygen vacancies. However, the existence of oxygen vacancies fundamentally causes photoexcited carrier trapping and large leakage current. Therefore, it is still challenging to limit oxygen vacancies while maintaining low bandgap and high ferroelectricity. Here, an efficient charge compensation strategy by finely adjusting the ion ratio on the A‐site to obtain an oxygen‐vacancy‐free relaxer ferroelectric is demonstrated in the system of Nax Biy TiO3‐BaTi0.5Ni0.5O3, where y > x. It is found that the oxygen‐vacancy‐free composition still yields strong visible–near‐infrared‐light‐absorbing and enhanced photoresponse, in which the photocurrent density doubles from ≈0.16 to ≈0.32 μA cm−2. A new bandgap tuning mechanism is proposed according to the local structural information of Ni ions obtained via extended X‐ray absorption fine structure. Moreover, this work succeeds in establishing the relationship between the concentration of oxygen vacancies and ferroelectric/piezoelectric properties of Nax Biy TiO3‐BaTi0.5Ni0.5O3. This research points out a promising route to the material design of bandgap engineered ferroelectrics with controlled defects, which is expected to benefit a wide range of functional energy conversion devices. 相似文献
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Moosa Nakhaee Badrabadi Rasul Ajeian Saeed Saleh ArdestaniMohammad Tavakkoli 《Organic Electronics》2012,13(11):2682-2687
We demonstrate the self-assembled growth of vertically aligned Copper Phthalocyanine (CuPc) nanorods which are directly evaporated on fullerene (C60) islands. UV–Vis spectroscopy of CuPc nanorods, compared to planar CuPc, shows an improvement in light absorption within the visible range. Moreover, scanning electron microscopy (SEM) demonstrates the presence of well-arranged vertically aligned CuPc nanorods suggesting an increase in the donor–acceptor interface. X-ray diffraction (XRD) reveals the crystalline nature of these nanorods. Different organic photovoltaic cells have been fabricated using these nanorods. High current density achieved with the cell arrangement of CuPc/CuPc-nanorods/C60 in comparison to regular planar CuPc/C60 device. The power conversion efficiency is also doubled compared to the planar one. 相似文献
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我国早在20世纪50年代开始研究太阳能电池,于1971年首次成功应用于我国发射的东方红二号卫星。我国的光伏产业发展经历了2个重要时期,第一个是在20世纪80年代中期,引进4条总计5MW的光伏电池生产线,光伏产业初步形成。第二个发展时期是在新世纪初,国家发改委在2002年启动了“送电到乡工程”,该工程光伏系统容量为20MW,极大的拉动了我国光伏市场的需求。国内光伏系统主要采用单位功率因数并网,不具备电能质量控制功能。因此,研究具有电能质量调节功能的光伏并网系统有重要意义。 相似文献
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Yasoub Eghbali Mahmoud Ferdosizade Naeiny 《International Journal of Communication Systems》2020,33(14)
In this paper, an off‐grid direction of arrival (DoA) estimation method is proposed for wideband signals. This method is based on the sparse representation (SR) of the array covariance matrix. Similar to the time domain DoA estimation methods, the correlation function of the sources was assumed to be the same and known. A new measurement vector is obtained using the lower‐left triangular elements of the covariance matrix. The DoAs are estimated by quantizing the entire range of continuous angle space into discrete grid points. However, the exact DoAs may be located between two grid points; therefore, this estimation has errors. The accuracy of DoA estimation is improved by the minimization of the difference between the new measurement vector and its estimated values. Simulation results revealed that the proposed method can enhance the DoA estimation accuracy of wideband signals. 相似文献
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Jonathan D. Servaites Sina Yeganeh Tobin J. Marks Mark A. Ratner 《Advanced functional materials》2010,20(1):97-104
Here, means to enhance power conversion efficiency (PCE or η) in bulk‐heterojunction (BHJ) organic photovoltaic (OPV) cells by optimizing the series resistance (Rs)—also known as the cell internal resistance—are studied. It is shown that current state‐of‐the‐art BHJ OPVs are approaching the limit for which efficiency can be improved via Rs reduction alone. This evaluation addresses OPVs based on a poly(3‐hexylthiophene):6,6‐phenyl C61‐butyric acid methyl ester (P3HT:PCBM) active layer, as well as future high‐efficiency OPVs (η > 10%). A diode‐based modeling approach is used to assess changes in Rs. Given that typical published P3HT:PCBM test cells have relatively small areas (～0.1 cm2), the analysis is extended to consider efficiency losses for larger area cells and shows that the transparent anode conductivity is then the dominant materials parameter affecting Rs efficiency losses. A model is developed that uses cell sizes and anode conductivities to predict current–voltage response as a function of resistive losses. The results show that the losses due to Rs remain minimal until relatively large cell areas (>0.1 cm2) are employed. Finally, Rs effects on a projected high‐efficiency OPV scenario are assessed, based on the goal of cell efficiencies >10%. Here, Rs optimization effects remain modest; however, there are now more pronounced losses due to cell size, and it is shown how these losses can be mitigated by using higher conductivity anodes. 相似文献
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J. C. Chen M. Ladle Ristow J. I. Cubbage J. G. Werthen 《Journal of Electronic Materials》1992,21(3):347-353
We have studied the heteroepitaxial growth of GaAs on Ge substrates by metal-organic chemical vapor deposition (MOCVD). Different
growth conditions and substrate orientations were employed to examine the properties of GaAs grown upon Ge substrates, and
in particular the GaAs/Ge interface. The interface properties were found to strongly depend on growth conditions. By small
changes in the growth temperature, the GaAs/ Ge interface was altered from active to passive. Only a narrow temperature window
(600 to 630° C) for the initial GaAs layer growth gave the passive-Ge junction together with good surface morphology. Accordingly,
a high efficiency (19%, AMO) GaAs solar cell was grown by atmospheric pressure MOCVD on a Ge substrate without any junction
in the Ge. 相似文献
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根据具体的工程实例阐述了太阳光伏系统的设计选型、注意事项,并对该系统进行了技术经济评价,对存在的问题作出了分析,提出了解决方法。 相似文献
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Tetsuyuki Ishii Takumi Takashima Kenji Otani 《Progress in Photovoltaics: Research and Applications》2011,19(2):170-179
Various kinds of photovoltaic (PV) modules have been developed and practically operated as PV systems up to present. Investigation of the long‐term reliability of PV modules is indispensable for the use of PV systems as reliable energy sources. In this study, we show the results of outdoor exposure test in which the performance of 14 PV modules composed of five different kinds made by six different PV manufacturers have been measured since July 2004. The average performance is calculated in each year from 2005 to 2008, and the performance degradation is quantitatively evaluated. The results are that the magnitude of the performance degradation can be clearly classified by the kinds of the PV modules. The performance difference of the single‐crystalline silicon (sc‐Si) modules between 2005 and 2008 is from 1.9% to 2.8%. Polycrystalline silicon (pc‐Si) modules show performance degradation from 0.7% to 1.4%. The performance of an amorphous silicon/crystalline silicon (a‐Si:H/c‐Si) decreased by 0.7%. Although a pair of a‐Si modules had been already exposed to sunlight for about 6 months, the pair of modules show 4.4% of performance degradation. More than half of the performance degradation happened during the initial period from 2005 to 2006. This indicates that it takes about 2 years until the performance of a‐Si modules is stable. The performance is quite stable after 2006. Interestingly, the performance of the cupper indium gallium diselenide modules in 2008 is about 0.8% higher than that in 2005. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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We report a new finding that ultra-thin Tris(8-hydroxyquinoline) aluminum (Alq3) improves an Al cathode interface for photovoltaic (PV) with inorganic amorphous silicon (a-Si) as well as organic bulk heterojunction (BHJ) photoactive layers. Contact resistance characterization is used to investigate the effect of the added Alq3. The experimental results show that the inserted Alq3 is observed to reduce the contact resistance at the cathode interface. Supported by our numerical analysis, the enhanced cathode interface by Alq3 provides better Ohmic contact, thereby increasing Voc. The overall power efficiency is enhanced accordingly benefited by the Alq3 added cathode regardless of photoactive layers. 相似文献
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太阳能光伏发电技术在建筑中的应用 总被引：1，自引：0，他引：1
本文阐述了太阳能光伏发电系统的基本组成及工作原理,提出了光伏发电系统与建筑一体化的概念,并分析了其发展优势。然后提出在九洲电气新建厂区建设太阳能光伏电站的设计构想,最后对此工程的发展前景进行了预测。 相似文献
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本文在对比逆变器输出侧L及LCL滤波器优劣的基础上,对500kW大功率光伏逆变器上的LCL滤波器参数选型做了详细分析。最后,在所选参数基础上,基于D—Q分解法,对500kW光伏逆变器进行了并网仿真,实现了单位功率因素并网运行。仿真证明了LCL滤波电路选型的正确性。 相似文献