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Two different approaches for designing a linear Fresnel reflector solar concentrator (LFRSC) with a flat horizontal absorber are described. The performance characteristics of both the designs are studied in detail. The distribution of local concentration ratio on the surface of the absorber, for each design, is investigated using the ray trace technique. Results of some typical numerical calculations are presented graphically and discussed. 相似文献
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Integration of solar concentrators with photovoltaic (PV) systems reduces the required number of PV panels, which often account for the major costs of PV systems. The linear Fresnel reflector mirror is considered more effective because of its simplicity and effortless fabrication. An experimental test rig of a concentrated PV/thermal system that employs a linear configuration and horizontal absorber was built for evaluating its electrical and thermal performances. The considered concentrator consists of various widths of flat glass mirrors, which positioned with different angles, and with sun light focusing on the PV cells that fixed over an active cooling system. The experimental investigation of the proposed concentrated PV/thermal system shows that higher electrical and thermal efficiencies can be achieved at comparatively high temperature levels than that typically utilized in a nonconcentrated PV/thermal system. The characteristics of PV cells also indicate that the electrical efficiency values in case of no concentration and with concentration ratio of 6.0 are 9.6%, and 11%, respectively. The measured values for the inlet and outlet cooling water temperatures of the receiver showed that the maximum outlet temperature reached was 75°C with a flow rate of 0.025 L/min, and the product thermal efficiency was 62.3%. These obtained results illustrate an adequate and good thermal and electrical performance under the meteorological weather conditions of the province of Al‐Karak in Jordan. 相似文献
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通过模拟优化计算,制作出4种聚光反射器,并进行了真空管空晒测试.把空晒温度及其变化趋势与当天太阳辐射条件的模拟结果进行了比较,新设计的几种非跟踪聚光反射器的集热效果都颇为理想,可应用于低温蒸汽发电、制冷空调和海水淡化等. 相似文献
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Yiding Cao 《国际能源研究杂志》2014,38(14):1812-1824
The objectives of this paper are to introduce a new heat engine and evaluate its performance. The new heat engine uses a gas, such as air, nitrogen, or argon, as the working fluid and extracts thermal energy from a heat source as the energy input. The new heat engine may find extensive applications in renewable energy industries, such as concentrating solar power (CSP). Additionally, the heat engine may be employed to recover energy from exhaust streams of internal combustion engines, gas turbine engines, and various industrial processes. It may also work as a thermal‐to‐mechanical conversion system in a nuclear power plant and function as an external combustion engine in which the heat source is the combustion gas from an external combustion chamber. The heat engine is to mimic the performance of an air‐standard Otto cycle. This is achieved by drastically increasing the time duration of heat acquisition from the heat source in conjunction with the timing of the heat acquisition and a large heat transfer surface area. Performance simulations show that the new heat engine can potentially attain a thermal efficiency above 50% and a power output above 100 kW under open‐cycle operation. Additionally, the heat engine could significantly reduce CSP costs and operate in open cycles, effectively removing the difficulties of dry cooling requirement for CSP applications. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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聚光太阳能发电技术应用与前景 总被引：4，自引：0，他引：4
陈于平 《电网与水力发电进展》2010,26(7):29-33
分析了聚光太阳能发电三大技术（线性聚光系统、碟/引擎系统、电力塔系统）以及热能储存系统,阐述了其结构、工作原理与研究方向,比较了这三大技术之间的经济技术性能,介绍了适合我国太阳能辐射量大的边远地区碟/引擎系统的应用,展示了太阳能热发电技术的应用前景及对节能减排的贡献。 相似文献
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塔式太阳能热发电站的聚光镜场大多是由按一定规律排列的矩形定日镜组成,在相邻定日镜间无机械碰撞的情况下,聚光镜场的最大土地利用率仅为58%。文章提出了选用规则交错排列的聚光镜场布置方案,建立不同形状定日镜的土地利用模型,并计算出不同情况下的最大土地利用率。通过仿真得出,矩形定日镜和六边形定日镜在一定长宽比时可获得最大土地利用率,其中六边形定日镜的土地利用率最高,约为100%。 相似文献
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To reduce the levelized cost of energy for concentrating solar power (CSP), the outlet temperature of the solar receiver needs to be higher than 700 °C in the next-generation CSP. Because of extensive engineering application experience, the liquid-based receiver is an attractive receiver technology for the next-generation CSP. This review is focused on four of the most promising liquid-based receivers, including chloride salts, sodium, lead-bismuth, and tin receivers. The challenges of these receivers and corresponding solutions are comprehensively reviewed and classified. It is concluded that combining salt purification and anti-corrosion receiver materials is promising to tackle the corrosion problems of chloride salts at high temperatures. In addition, reducing energy losses of the receiver from sources and during propagation is the most effective way to improve the receiver efficiency. Moreover, resolving the sodium fire risk and material compatibility issues could promote the potential application of liquid-metal receivers. Furthermore, using multiple heat transfer fluids in one system is also a promising way for the next-generation CSP. For example, the liquid sodium is used as the heat transfer fluid while the molten chloride salt is used as the storage medium. In the end, suggestions for future studies are proposed to bridge the research gaps for > 700 °C liquid-based receivers. 相似文献
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Results of optical and thermal performance evaluation tests conducted on a prototype linear Fresnel reflector system fabricated using locally available material are presented in this paper. 相似文献
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Screening of high melting point phase change materials (PCM) in solar thermal concentrating technology based on CLFR 总被引：2，自引：0，他引：2
We have investigated the suitability of high melting point phase change materials for use in new, large scale solar thermal electricity plants. Candidate materials for latent heat thermal energy storage are identified and their operating parameters modeled and analysed. The mathematical characteristics of charging and discharging these storage materials are discussed. Several high melting point, high conductivity materials are shown to be suitable and advantageous for use with solar thermal electricity plants, such as Sydney University’s novel, low cost CLFR and MTSA collector systems, as well as existing parabolic trough and tower technologies. 相似文献
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Results of a preliminary techno-economic appraisal of solar thermal power generation at three locations in India are presented. The study uses System Advisor Model developed by NREL, USA. The results of the study provide useful insight into (a) selecting appropriate reference direct normal irradiance for design of solar thermal power plants, (b) identifying suitable combinations of solar multiple and hours of thermal energy storage and (c) cost reduction potential. The parabolic trough technology is used for exemplifying the procedure for this purpose. The estimated levelised unit cost of electricity is in the range of Rs (US$1=Indian rupees 51.66 on 5 October 2012) 16–21 per kWh for the most likely range of input parameters. The results also indicate possibility of about 30% reduction in unit cost of electricity by year 2021. 相似文献
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Thermal energy storage(TES) is an important part of concentrating solar power(CSP) plants. The primary advantage of TES in CSP plants is the ability to dispatch electrical output to match peak demand periods and reduce the levelized cost of electricity. The major challenge of the molten salt is its high freezing point, leading to additional complicating freeze protection. This paper presents the experimental results of melting process of a mixed nitrate salt with a melting temperature of 115°C i... 相似文献
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太阳能热发电是将太阳能转化为热能,通过热功转化过程发电的技术.太阳能热发电站具有发电功率相对平稳可控,运行方式灵活,可进行热电并供等优势,同时具有非常好的环境效益.太阳能热发电规模化发展后,近期能够作为调峰电源为风力发电,光伏发电等间歇性电源提供辅助服务.随着未来技术的优化提升,由大型太阳能热发电站组成的太阳能热发电厂有可能承担电力系统基础负荷.目前,全球太阳能热发电产业正在兴起,装机容量逐年增加,然而,我国在太阳能热发电关键技术研究上明显落后于先进国家,太阳能热发电产业发展速度明显滞后;另外,我国也没有发布明确的太阳能热发电产业激励政策,这直接导致了一批项目迟迟不能落地. 相似文献
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为提高太阳能光热转换效率,对同轴非完整型平移抛物面聚光系统进行三维建模,采用蒙特卡洛光线追踪法进行追踪。分别改变接收器和聚光器放置位置,对聚光系统进行优化。通过分析双面受热平板接收器的能量传递及转换过程,建立平板接收器的理论计算模型。对接收器进行热性能计算,分析其热性能的变化规律。研究表明:综合考虑接收器辐射强度均值、辐射热流均匀性、辐射面积等因素的影响,选择将接收器吸热板放置于抛物面轴线远离焦点20~35 mm范围内;环境温度在0~30℃变化时,与单面受热接收器相比,双面受热接收器的热效率提高了8.18%~37.01%。 相似文献
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M. A. Serag-Eldin 《国际可持续能源杂志》2014,33(3):506-524
The paper presents a mathematical model for the thermal design of a new solar energy collection system adopted to drive an absorption chiller for air-conditioning a modern desert home. The collection system employs roof-mounted, retractable compact linear Fresnel mirrors. The conceptual design is described, and the mathematical model is presented. A hypothetical, two-floor home located in a typical desert site is employed for demonstration. The performance of the proposed solar collection system is evaluated employing a mathematical model presented here. Investigations are conducted to assess the effect of various design parameters on system efficiency. It is concluded that it is feasible to carry the entire house cooling loads employing only solar power collected with the proposed roof-mounted system, even though the house is located in an exceptionally hot desert environment. Moreover, the proposed system may require less roof space than a Photovoltaic-based system when correct conditions are present. 相似文献
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Concentrating solar technologies are promising renewable energy systems for exploiting incident beam solar irradiation with high exergy efficiency values. These systems provide the possibility for producing useful heat at high temperatures that can be utilized by highly efficient power cycles or producing directly solar fuels with receiver reactor technology. In the last years, the concept of beam-down concentrating solar technology gains more and more attention due to a series of advantages associated with this idea. This concept is based on the use of two-stage reflectors for concentrating solar irradiation close to the ground, something that leads to a more compact system with reduced height. Furthermore, the high-temperature heat production and the chemical processes take place on the ground and not at a great height, increasing the safety levels of the system. Moreover, this design leads to compact configurations with lower materials use, lower wind loads and without the need to move the receiver for tracking the sun.The objective of this review is to present the recent progress on beam-down solar concentrating technology and to highlight the need for giving attention to this direction. Critical advantages of this technology are demonstrated and the associated limitations are discussed. The emphasis is on the presentation of the different technologies that can be coupled with the beam-down technology. Thermodynamic power cycles (Brayton, Rankine and Stirling), photovoltaics, thermochemical processes, as well as other applications are included and discussed. Practically, power production and solar fuels are the major useful outputs that can be generated by beam-down solar concentrating configurations. The reviewed technologies are critically discussed and compared in terms of energy, economic and environmental aspects. Future steps in the field are suggested based on the existing literature. 相似文献