并网光伏电站关键部件的运行性能分析

简要概述了50kW大型并网光伏电站的系统构成；通过一段时间的运行，对该电站的一些关键部件进行性能评价。分析结果表明：电站的光伏组件设计合理，并网逆变器具有较高的转换效率。     

100kW_p光伏幕墙并网系统性能分析

对云南师范大学能源与环境科学学院100 kW_p光伏幕墙并网系统进行了在线统计研究,分析了日发电量、月发电量,以及系统的工作电压、工作电流、发电时间、晴天、阴天等运行状态和规律,为光伏幕墙并网系统提供了实例参考依据。     

光伏并网电站仿真与决策优化软件设计

针对太阳能光伏并网电站系统,建立"太阳能辐照+光伏组件+逆变器+损耗"一系列数学模型,采用编程软件实现光伏电站并网系统的仿真和决策优化设计软件。该软件主要以世界各地典型年气象数据为基础,用以仿真获得光伏阵列表面辐照度、光伏阵列发电功率、光伏逆变器输出功率、系统总损失以及系统净输出发电参数等,其结果能反映实际电站建成后的发电情况。     

三相60kW光伏并网发电系统

1引言 光伏并网发电是近几年才发展起来的新技术，它为光伏的大规模利用提供了广阔的市场空间，代表着未来的前进方向。我国在光伏并网发电技术方面的研发起步较晚，尚处于研究试验阶段，但近两年来光伏并网发电技术已得到了业内人士的广泛关注。2003年5月，由新疆新能源研究所、合肥工业大学、合肥阳光电源三家单位组成产、学、研联合攻关团队，在成功开发与研制500W、3kW光伏并网系统、100kW柔性衬底非晶硅并网电站和50kW光伏电站计算机智能控制系统基础上，研制开发出三相60kW光伏并网逆变装置，并网电站于2005年3月27日在新疆新能源研究所建成并投入发电，至2005年8月27日，已累计发电25700kWh。     

太阳能光伏发电系统的系统分类

正太阳能光伏发电系统分为独立光伏发电系统、并网光伏发电系统及分布式光伏发电系统。a)独立光伏发电系统也叫离网光伏发电系统。主要由太阳能电池组件、控制器、蓄电池组成,若要为交流负载供电,还需要配置交流逆变器;b)并网光伏发电系统就是太阳能组件产生的直流电经过并网逆变器转换成符合市电电网要求的交流电之后直接接入公共电网。并网光伏发电系统有集中式大型并网光伏电站,一般都是国家级电站,主要特点是     

大型光伏并网电站功率预测系统设计

西部大型光伏电站运行中普遍遇到并网调度难的问题,通过光伏并网电站功率预测系统(PV-GPPS)可以极大地提高大型光伏电站并网的可调度性。阐述了大型并网光伏电站功率预测系统的研究设计方案,通过对光伏并网电站功率预测系统实现的基本原理、数学模型进行分析,提出了考虑数值天气预测的基于SCADA、计算机信息技术的PV-GPPS的实现途径,对开发光伏并网电站功率预测系统具有一定指导意义和参考价值。     

与景观结合的奥运森林公园并网光伏发电系统

并网光伏发电系统与奥运森林公园景观相结合,体现了"绿色奥运、科技奥运、人文奥运"三大理念,是清洁能源技术在奥运会中的应用。并网光伏发电系统设计中采用了MPPT技术、防孤岛效应技术、逆功率反送保护技术和完善的并网光伏发电系统监控技术,提高了并网光伏发电系统运行的可靠性和电网的安全性。奥运期间奥运区域供电等级提升为特级,为满足供电可靠性,示范电站采用带功率流向检测的并网模式,当并网光伏发电系统的有功功率超过指定负载的有功功率时,切断并网光伏发电系统,防止电能馈入电网。     

600 kW_p太阳能光电建筑一体化车棚的应用

介绍了600 kW_p太阳能光电建筑一体化车棚用户侧并网发电系统的原理、设计原则及系统设计,对微晶硅薄膜光伏组件和CIGS(铜铟镓硒)光伏组件的实际运行效果和产电量情况进行了对比。数据对于系统组件选型和应用提供了指导和有价值的参考。     

基于机理模型的并网光伏电站实时效率分析

目前并网光伏电站实时效率分析还缺少实际的算法和研究。针对该问题,首先根据经典天球坐标系统理论提出分析效率时需要计算数据;再根据太阳辐照原理得出固定倾角光伏组件的理论发电量,并根据某电站的地理经度、组件实时工作温度修正后,计算出该光伏电站的实时效率;最后根据该电站的实际运行情况,提出设计的不足和提高电站发电效率的措施。     

1MW高倍聚光光伏发电并网系统的设计

本文选云南石林地区为电站场址,通过对高倍聚光光伏组件选择、光伏阵列运行方式选择、光伏阵列设计及布置方案、并网逆变器选型等光伏发电系统构成方面进行了研究设计.分析得出该电站的理论年发电量为170.07万kWh,具有良好的经济效益和环保效益.     

Influence of a building’s integrated-photovoltaics on heating and cooling loads

Building integrated photovoltaics (BIPV) has the potential to become a major source of renewable energy in the urban environment. BIPV has significant influence on the heat transfer through the building envelope because of the change of the thermal resistance by adding or replacing the building elements. Four different roofs are used to assess the impacts of BIPV on the building’s heating-and-cooling loads; namely ventilated air-gap BIPV, non-ventilated (closed) air-gap BIPV, closeroof mounted BIPV, and the conventional roof with no PV and no air gap. One-dimensional transient models of four cases are derived to evaluate the PV performances and building cooling-and-heating loads across the different roofs in order to select the appropriate PV building integration method in Tianjin, China. The simulation results show that the PV roof with ventilated air-gap is suitable for the application in summer because this integration leads to the low cooling load and high PV conversion efficiency. The PV roof with ventilation air-gap has a high time lag and small decrement factor in comparison with other three roofs and has the same heat gain as the cool roof of absorptance 0.4. In winter, BIPV of non-ventilated air gap is more appropriate due to the combination of the low heating-load through the PV roof and high PV electrical output.     

Pilot study on building-integrated PV: Technical assessment and economic analysis

Building-integrated photovoltaics (BIPV) is an innovative green solution that incorporated energy generation into the building façade with modification on the building material or architectural structure. It is a clean and reliable solution that conserves the aesthetical value of the architecture and has the potential to enhance the building's energy efficiency. Malaysia's tropical location has a high solar energy potential to be exploited, and BIPV is a very innovative aspect of technology to employ the available energy. Heriot-Watt University Malaysia (HWUM) has a unique roof design that could be utilized as an application of the BIPV system to generate electricity, reducing the carbon footprint of the facility. Eight BIPV systems of different PV technologies and module types and with capacities of 411.8 to 1085.6 kW were proposed for the building. The environmental plugin software has been integrated with a building geometry modelling tool to visualize and estimate the energy potential from the roof surface in a 3D modelling software. Additionally, detailed system simulations are conducted using PVSyst software, where results and performance parameters are analysed. The roof surface is shown to provide great energy potential and studied scenarios generated between 548 and 1451 MWh yearly with PR range from 78% to 85%. C-Si scenarios offer the best economical profitability with payback period of 4.4 to 6.3 years. The recommended scenario has a size of 1085.5 kW and utilizes thin-film CdTe PV modules. The system generates 1415 MWh annually with a performance ratio of 84.9%, which saves 62.8% of the electricity bill and has an estimated cost of 901 000 USD. Installation of the proposed system should preserve the aesthetical value of the building's roof, satisfy BIPV rules, and most importantly, conserves energy, making the building greener.     

Practical application of building integrated photovoltaic (BIPV) system using transparent amorphous silicon thin-film PV module

An analysis has been carried out on the first practical application in Korea of the design and installation of building integrated photovoltaic (BIPV) modules on the windows covering the front side of a building by using transparent thin-film amorphous silicon solar cells. This analysis was performed through long-term monitoring of performance for 2 years. Electrical energy generation per unit power output was estimated through the 2 year monitoring of an actual BIPV system, which were 48.4 kWh/kWp/month and 580.5 kWh/kWp/year, respectively, while the measured energy generation data in this study were almost half of that reported from the existing data which were derived by general amorphous thin-film solar cell application. The reason is that the azimuth of the tested BIPV system in this study was inclined to 50° in the southwest and moreover, the self-shade caused by the projected building mass resulted in the further reduction of energy generation efficiency. From simulating influencing factors such as azimuth and shading, the measured energy generation efficiency in the tested condition can be improved up to 47% by changing the building location in terms of azimuth and shading, thus allowing better solar radiation for the PV module. Thus, from the real application of the BIPV system, the installation of a PV module associated with azimuth and shading can be said to be the essentially influencing factors on PV performance, and both factors can be useful design parameters in order to optimize a PV system for an architectural BIPV application.     

Feasibility analysis of solar photovoltaic array cladding on commercial towers in Doha,Qatar – a case study

Building-integrated photovoltaic (BIPV) technology has become a major area of research due to environ-mental concerns. This article studies the feasibility of cladding high-rise towers in Doha with solar photovoltaic modules. Specifically, the case of the Qatar Financial Centre (QFC) is discussed. The major aim of the work is to evaluate the technical feasibility, economic impact and environmental effects of using photovoltaic panels on commercial towers in Qatar. Experimental data on solar irradiance and the effect of shading on the QFC Tower are presented. Numerical calculations are done using solar pathfinder software. The studies show that, although there is a significant amount of saving in CO₂ emission by using BIPV on towers in Doha, the payback period is still very long due to the cheaper cost of grid electricity in Qatar and poor conversion efficiency of PV panels. The complete system layout is presented and viable solutions are investigated.     

The effect of using two PCMs on the thermal regulation performance of BIPV systems

Building Integrated Photovoltaics (BIPVs) is one of the most promising applications for Photovoltaics (PVs). However, when the temperature in the BIPV increases, the conversion efficiency deteriorates. A PV/PCM system using Phase Change Materials (PCM) for BIPV thermal control has been experimentally and numerically studied previously. One of the main barriers for this application is how to improve the low thermal conductivity of the PCM in order to achieve a quick thermal dissipation response with longer thermal regulation in PVs. Although the metal fins inserted inside the PCM can improve the heat transfer, the thermal regulation period declines as the volume of the PCM is substituted by the metal mass of the PV/PCM system. A modified PV/PCM system integrated with two PCMs with different phase transient temperatures for improving the heat regulation needs to be investigated. The use of combinations of PCMs, each with a set of different phase transient temperatures, is expected to enhance the thermal regulation effect of the PV/PCM system and lengthen the thermal regulation time in PVs. In this study a developed PV/PCM numerical simulation model for single PCM application has been modified to predict the thermal performance of the multi-PCMs in a triangular cell in the PV/PCM system. A series of numerical simulations tests have been carried out in static state and realistic conditions in UK. The thermal regulation of the PV/PCM system with a different range of phase transient temperature PCMs has been discussed.     

Assessing the technical and economic performance of building integrated photovoltaics and their value to the GCC society

This paper assesses the technical and economic performance of PV technology integrated into residential buildings in the Gulf Cooperation Council (GCC) countries. It highlights the value of PV electricity for the GCC society from the perspective of consumers, utilities and environment. Through a systematic modelling analysis it is shown that the efficiency of PV system drops by 4–6% due to high range of module temperature and also a change in power output due to high ambient temperatures. Consequently, the outputs of horizontal and vertical PV modules are found to be less than estimates based on standard test conditions. Economically, this study shows that building integrated photovoltaic (BIPV) systems are not viable in GCC countries and cannot compete with conventional electricity sources on a unit cost basis. From a society point of view, however, the integration of PV technology into buildings would have several benefits for the GCC countries, including: first, savings in capital cost due to central power plants and transmission and distribution processes; second, an increase in the exported oil and natural gas used for electricity generation; and third, a reduction in the CO₂ emissions from conventional power plants. When these considerations are taken into account then BIPV should become a feasible technology in GCC countries.     

太阳能光伏光热建筑一体化系统的研究

太阳能光伏光热一体化不仅能够有效降低光伏组件的温度,提高光伏发电效率,而且能够产生热能,从而大大提高了太阳能的转换效率。对光伏光热建筑一体化(BIPV/T)系统的两种主要模式:水冷却型和空气冷却型系统的工作原理和系统模型进行了理论介绍,详细说明了两种系统中热产品在家庭中的应用。并对目前研究情况下两个系统中存在的问题提出了改进方案。与常规建筑相比,光伏光热建筑减少了墙体得热,改善了室内空调负荷状况,提高了建筑节能效果。     

Equilibrium thermal characteristics of a building integrated photovoltaic tiled roof

Photovoltaic (PV) modules attain high temperatures when exposed to a combination of high radiation levels and elevated ambient temperatures. The temperature rise can be particularly problematic for fully building integrated PV (BIPV) roof tile systems if back ventilation is restricted. PV laminates could suffer yield degradation and accelerated aging in these conditions. This paper presents a laboratory based experimental investigation undertaken to determine the potential for high temperature operation in such a BIPV installation. This is achieved by ascertaining the dependence of the PV roof tile temperature on incident radiation and ambient temperature. A theory based correction was developed to account for the unrealistic sky temperature of the solar simulator used in the experiments. The particular PV roof tiles used are warranted up to an operational temperature of 85 °C, anything above this temperature will void the warranty because of potential damage to the integrity of the encapsulation. As a guide for installers, a map of southern Europe has been generated indicating locations where excessive module temperatures might be expected and thus where installation is inadvisable.     

Double skin facades (DSF) and building integrated photovoltaics (BIPV): A review of configurations and heat transfer characteristics

This article presents the state of the knowledge on the thermal analysis of double skin facades with integrated photovoltaic (PV) panels called the Building Integrated Photovoltaics (BIPV) in terms of the published studies carried out on these systems. The idea of integration of the PV panels by replacing building elements, increase the prospects of the renewable energy systems. Taking also into account the need to use more renewable energy systems in buildings, the investigation of the BIPV systems to improve their performance is of a great importance. The literature studies are separated into experimental and theoretical for naturally ventilated systems and mechanically ventilated with external means e.g. fan use. It is concluded that most researchers studied the systems with mechanical ventilation rather than the systems with natural ventilation because the latter are more complex in terms of the air flow behaviour in the air duct. Additionally, various researchers proposed Nu number correlations and convective heat transfer correlation under several assumptions and conditions every time, for different range or Ra number which are presented and compared in this paper.     

Grid-connected building-integrated photovoltaics: a Hong Kong case study

The first building-integrated photovoltaic system (BIPV) in Hong Kong has been working successfully for three years, as remote system for the first year and grid-connected system in the last two years. A number of issues have been investigated on the experimental system including technical, economical, operation and management topics. This paper presents the findings from this research project funded by the Industrial Support Fund of the Hong Kong SAR Government. Simulation and data monitoring have been completed for energy performance of the BIPV system under Hong Kong weather conditions. The natural ventilation effect of an air gap on PV module’s power output and heat transfer across the PV wall and PV-roof have been investigated. Good agreement between simulation and experimental results was achieved. The system can provide about 41% of electric power for an indoor lighting floor area circuit of 250 m². The harmonics of the power output from the PV system was also measured to check the interference level to the utility grid. Experiments show that the total harmonics current distortion of the grid-connected BIPV system is far lower than that from some conventional equipment, such as personal computers. The total harmonics from this BIPV system is less than 12% for most of the time, even when the incident solar irradiation is very weak.