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太阳能电池的工作原理是光电效应,主要是以半导体材料为基础,利用光照产生电子-空穴对,在PN结上可以产生光电流和光电压的现象。我国实验室光伏电池的效率为21%,可商业化光伏组件效率达14%~15%,一般商业电池效率10%~13%。目前,世界上太阳能电池最高转化效率已达32%。2005年世界光伏系统装机总容量达1460MW,比2004年增长34%,中国光伏系统安装量仅为65MW。太阳能电池产量由2004年的1146MW上升到2005年的1656MW。国际市场目前需求稳定增长。太阳能光伏发电示范工程等是近期国内需求增长的主要因素。沙漠发电、城市屋顶计划是未来需求大幅增长的动力。于2006年1月1日起施行的《中华人民共和国可再生能源法》规定:“国家鼓励单位和个人安装和使用太阳能热水系统、太阳能供热采暖和制冷系统、太阳能光伏发电系统等太阳能利用系统”。 相似文献
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太阳能电池是利用光生伏打效应将太阳辐射能直接转换为电能的器件,是太阳能光伏发电系统的核心技术基础组成部件。目前困扰太阳能光伏发电技术发展和广泛应用的主要问题,是提高效率和降低成本两大问题。紧紧围绕提高光电转换效率和降低生产成本两大目标的各种新型太阳能电池的研究开发工作, 相似文献
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北京南站太阳能光伏发电系统设计探讨 总被引:1,自引:0,他引:1
介绍了北京南站太阳能光伏建筑一体化并网发电系统(光伏组件总安装容量240 kWp,系统年输出电量为22万kW·h),对站房屋面太阳能发电材料的选择进行了详细描述(最后确定采用不透光的铜铟镓硒太阳能电池),并分别介绍了太阳能光伏电池方阵、光伏并网逆变器、汇线盒、电涌保护器、直流配电柜、交流配电柜的选用.进行了技术经济比较和环境、社会效益分析. 相似文献
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光伏发电产品理念 从广义上讲,凡是电工产品都可进行太阳能光伏发电,然而实际上仅有很少的品种可归结到该行列中。这里所指的太阳能电池又称光伏电池(PV),即和太阳能电池一体化或离开太阳不可单独工作的产 相似文献
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充分利用太阳能资源是我国法律、政策、规范多方面的要求。随着我国能源转型与能源革命的推进、国家能源形势的变化、“双碳”目标的分解落实,在城市内充分挖掘可再生资源是有效可行的城市降碳技术路线。然而在城市里,可利用太阳能的场地空间十分有限。如何最大化利用有限的建筑屋面资源,如何取舍太阳能热水系统、光伏发电系统,是建筑规划设计阶段需要认真考虑的问题。对太阳能热水系统、电辅助加热系统、空气源热泵热水系统、光伏发电系统组合分析。考虑太阳能资源、气温等因素逐日计算各系统运行效果,综合对比不同组合方案定性定量指标。发现光伏发电+空气源热泵热水系统多方面指标均优于太阳能热水系统+常规辅助系统。因此,建议在规划设计太阳热水系统时应先充分论证建设光伏发电系统必要性。 相似文献
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目前,世界光伏市场每年保持约30%的增长率。由于光伏系统组件构成的复杂性,光伏组件如光伏板等的整体效率往往低于单个光伏电池的效率。光伏板部分阴影遮挡是造成光伏系统能源效率偏低的主要原因之一。部分阴影遮挡造成的光伏系统组件不匹配将导致太阳能板的局部过热从而降低其使用寿命,严重时导致热斑问题从而可能引起电站火灾。商业光伏板一般采用单晶硅、多晶硅和非晶硅三种材料,其中非晶硅由于特殊的反向电压特性和不同的制作工艺,在发生局部遮挡时会产生与其他两种材料的太阳能电池不一样的电学特性。利用M atlab Simulink平台结合实验数据建立准确的非晶硅电池板局部阴影电学模型,得到当完全遮挡一个或多个非晶硅电池时的阴影区电池工作点,然后输入到Matlab PDE Tool建立的热学模型,分析电池局部温升现象,得到热斑产生条件,从而提出防治热斑的一些措施。 相似文献
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Building-integrated photovoltaic/thermal (BIPV/T) system has been considered as an attractive technology for building integration. The main part of a BIPV/T system is PV/T collector. In order to solve the non-uniform cooling of solar PV cells and control the operating temperature of solar PV cells conveniently, a heat pipe photovoltaic/thermal (PV/T) hybrid system (collector) has been proposed and described by selecting a wick heat pipe to absorb isothermally the excessive heat from solar PV cells. A theoretical model in terms of heat transfer process analysis in PV module panel and introducing the effectiveness-number of transfer unit (?-NTU) method in heat exchanger design was developed to predict the overall thermal-electrical conversion performances of the heat pipe PV/T system. A detailed parametric investigation by varying relevant parameters, i.e., inlet water temperature, water mass flow rate, packing factor of solar cell and heat loss coefficient has been carried out on the basis of the first and second laws of thermodynamics. Results show that the overall thermal, electrical and exergy efficiencies of the heat pipe PV/T hybrid system corresponding to 63.65%, 8.45% and 10.26%, respectively can be achieved under the operating conditions presented in this paper. The varying range of operating temperature for solar cell on the absorber plate is less than 2.5 °C. The heat pipe PV/T hybrid system is viable and exhibits the potential and competitiveness over the other conventional BIPV/T systems. 相似文献
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《Energy and Buildings》2005,37(11):1132-1146
The reduction of greenhouse gas emissions in the building sector to a sustainable level will require tremendous efforts to increase both energy efficiency and the share of renewable energies. Apart from the lowering of energy demand through better insulation and fenestration, small combined heat and power (micro-cogeneration) systems may help improve the situation on the supply side by cutting both the non-renewable energy demand for residential buildings and peak loads in the electric grid. Though still on the brink of market entry, fuel cells are the focus of interest as the prime technology for such systems. In this study, a methodology for assessing the performance of such systems in terms of primary energy demand and the CO2 emissions by transient computer simulations is established, and demonstrated for a natural gas driven solid oxide fuel cell (SOFC) and, to a lesser extend, a polymer electrolyte fuel cell (PEFC) home fuel cell cogeneration system. The systems were evaluated for different grid electricity generation mix types and compared to traditional gas boiler systems. The interaction with hot water storage and solar thermal collectors, and the impact of storage size and predictive control was analyzed. Typical heat and electricity demand load profiles for different types of residential buildings and occupancy were considered, and the sizing of the fuel cell system in relation to the heat demand of the building was analyzed. Primary energy savings decline for cases with lower heat demand and for cases with solar thermal systems, and peak for fuel cell systems sized in accordance with the heat demand of the building. Future assessments of fuel cell systems will need a refined methodology, and depend on realistic performance characteristics and models that accurately consider dynamic conditions. 相似文献
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太阳能-空气源热泵热水系统作为可再生能源已得到广泛应用,但在我国北方寒冷地区运用较少。再加上空气源热泵自身存在低温环境运行效率过低甚至损坏机组的现象,需要对不同辅助热源辅助太阳能热水系统进行经济技术比较分析,以得到最佳的运行方案。通过对不同辅助热源辅助太阳能热水系统进行技术分析与计算,建立数学模型,模拟计算加热100 t水的全年运行情况,计算、分析不同辅助热源太阳能热水系统运行方案在长春地区的年运行总成本,结果表明:太阳能-空气源热泵-水源热泵热水系统在我国北方寒冷地区使用有很可观的发展空间。 相似文献
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