谈聚光型太阳能热发电工程设计中的三个概念

<正>随着环境保护压力的增大和太阳能热发电技术的成熟,各国热发电技术公司逐渐开始开拓中国市场。为了确切描述和对比不同聚光式太阳能热发电系统的配置,比较采用不同技术方案系统的性能和经济性。研究设计聚光式太阳能热发电系统时引入了容量系数、设计工况和太阳岛倍率三个概念。容量系数是指聚光式太阳能发电厂在当地日照资     

太阳光抛物面反射镜盘的工作原理

正据《Gas Turbine World》2015年7~8月刊报道,聚光太阳能发电技术直接接收太阳光辐射,集热并传输到接收器。通过类似熔盐的载热流体,输送热量;然后用于发电。由于聚光太阳能集热装置不同,可采用各种布置方式。与其聚光太阳能发电技术相比,碟式/斯特林发动机系统发电量较小在3~25 k W的范围内。该系统使     

碟式聚光太阳热发电技术

太阳热发电技术是利用太阳集热器把太阳能聚集起来,将工质加热到一定的温度,驱动热机带动发电机发电。由于整个系统的热源来自太阳能,所以称为太阳热发电技术。太阳能热发电系统一般由聚光系统、集热系统、热传输系统、蓄热贮能系统、热机系统等组成。当前太阳热发电技术主要有以下5种:(1)中央塔式(2)槽式(3)单碟独立电站和碟群体系(4)太阳烟囱(5)太阳池。本文通过介绍国外碟式太阳热发电技术的现状及发展趋势,提出发展我国碟式热发电技术的建议与思考。1碟式太阳热发电技术的历史与现状a.碟式热发电系统现代碟式太阳能热发电技术在20世纪70…     

太阳能热发电系列文章(6)聚光太阳能热发电的控制系统

聚光类太阳能热发电技术是指利用聚光器收集太阳能,通过接收器转换成热能,加热工质,驱动热动力装置进行发电的技术。现有的聚光类太阳能热发电系统按照形式不同可分为槽式太阳能热发电系     

聚光光伏发电国内外研究现状

从国内外聚光光伏发电技术的主要研究方向入手,分别介绍了聚光倍率、聚光器、太阳能跟踪方式、冷却与热管理系统4方面的研究现状,展望了太阳能聚光光伏技术的应用前景。     

聚光热发电技术的分析和简评

基于传热学、工程热力学的基本原理,结合实际应用,对槽式、塔式、碟式、分立式4种太阳能聚光热发电技术的特点、局限性、发展潜力进行初步分析。槽式技术是最成熟的聚光热发电技术,但是受聚光集热特性的影响,提高发电效率的难度较大;建议塔式技术优化跟踪聚光技术,以提高聚光效率,同时选择合适的单塔功率;为了充分发挥碟式技术的高温潜力,需要开发超高温热机;分立式技术提高了聚光效率,简化跟踪系统,但聚光采用的高次曲面镜价格昂贵。建议聚光技术可直接将高温工艺热应用于终端,提高热利用效率;远期可考虑高温热解制氢,利用氢气便于储存的优势,克服太阳能不稳定的先天缺陷。     

线性菲涅耳太阳能聚光系统

线性菲涅耳聚光反射装置是对连续抛物面聚光镜的一种离散化近似,因由法国工程师Fresnel发明而得名。线性菲涅耳太阳能热发电技术在太阳能热发电系统中非常有用,尤其是在需要安装大面积的镜场时,对成熟的槽式太阳能聚光热发电系统形成强有力的竞争。简要介绍了线性菲涅耳聚光反射装置的技术特点及发展现状。     

研究表明太阳能发电潜力很大

<正>一项对聚光太阳能发电(CSP)技术及其实际应用潜力的新研究显示,CSP可以提供脱碳能源系统中大部分的电力。据发表在《自然气候变化》杂志上的研究论文显示,聚光太阳能发电可以满足当前大量的能源需求。例如,在地中海地区,该研究显示联网的聚光太阳能发电系统,可提供当前电力需求的70%~80%,还不比燃气电厂的成本高。其生产的电力类似于一个标准能源生     

聚光型太阳能光伏遮阳系统应用研究

随着国内能源供需矛盾的日益突出,以太阳能光伏发电为代表的新能源产业将扮演解决能源危机的重要角色.在国内外光伏建筑一体化(BIPV)产业大背景下,研究如何提高太阳能光伏光电转换效率,降低系统成本,将成为未来很长一段时期光伏发电领域的重要课题.叙述了聚光型太阳能光伏技术与聚光型太阳能光伏遮阳系统的概念,分析了聚光型太阳能光...     

塔式太阳能热发电技术现状及发展浅析

本文扼要概述太阳能热发电系统的基本概念,在太阳能热发电的型式中,塔式的聚光比最高,简要介绍了塔式太阳能热发电技术发展趋势,阐述了塔式热发电国内外进展情况。     

碟式斯特林发动机的研究进展

太阳能的利用和斯特林发动机的研发符合目前解决全球能源危机问题的需要。对斯特林热机的发展过程和循环工作原理进行了总结,综述了国内外对于碟式斯特林发电技术的应用现状,归纳了碟式斯特林发电系统中太阳光跟踪控制系统、接收器聚热技术、斯特林发动机功率控制技术和斯特林发动机密封技术等关键技术的研究成果和应用现状,总结并展望了碟式斯特林发电技术的发展重心,为进一步的研究工作提供参考。     

太阳能光热发电技术综述

从经济、环境和社会角度来看,目前的能源供应和使用趋势明显不是可持续的。太阳能聚光光热发电（CSP）技术给拥有充足光照资源的地区带来了希望。太阳能聚光光热发电（CSP）技术可为法向直接日射辐照度（DNI）强的地区提供低碳、可再生能源。该文在简要分析太阳能光热发电技术现状基础上,介绍了太阳能光热发电当前的主要技术以及如何提高太阳能热发电实用性的相关技术。通过使用储热系统、后备燃料或带燃料的混合动力发电可以提高太阳能热发电的实用性。     

Potential application of concentrating solar power systems for the generation of electricity in Thailand

This study aims to investigate a potential application of concentrating solar power (CSP) systems for producing electricity in the tropical environment of Thailand. An 8-year period (1995–2002) of satellite data was used to generate the direct normal irradiation map of the country. The map reveals that the areas which receive the highest irradiation are mainly in the Northeast and the Central regions of the country, with the yearly sum of direct normal irradiation in the range of 1350–1400 kW h/m² year. The location of Ubon Ratchathani (15.25 °N, 104.87 °E) situated in the Northeast was selected as a target area for investigating the potential application of CSP systems. The performance of three 10 MW CSP systems, namely the parabolic trough, the tower and the dish/Stirling engine systems was investigated. A software named TRNSYS together with the solar thermal electric components (STEC) subroutines were used to simulate the systems. The yearly production of electricity from these systems was estimated and used for the economic evaluation of the systems. It was found that the parabolic trough system afforded the lowest levelized electricity cost of 0.30 USD/kW h. Based on the technical and economic considerations, this system has a sufficient potential for producing electricity in this region.     

太阳能热发电产业发展障碍分析

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。目前商业化的太阳能热发电项目在全球逐步推进。然而我国的太阳能热发电处于产业化起步阶段,相关产业链上的产品还处于试制和产业化的前期阶段,关键技术产品仍需要进一步验证。我国太阳能直射辐射资源的调查体系,不能满足日益发展的太阳能资源开发利用需求,同时也缺乏电站整体系统设计、系统集成、建设以及运营的能力和经验。太阳能热发电相关检测体系、标准体系还是空白,无法验证我国生产的产品的性能和可靠性。为了推动太阳能热发电的产业建设和发展,需要政策层面上重点鼓励、支持太阳能热发电的技术研发,示范工程的建设,以此带动市场规模的扩大。     

Development of a low-cost dish solar concentrator and its application in zeolite desorption

This paper deals with the development and performance characteristics of a low-cost dish solar concentrator and its application in zeolite desorption. The dish solar concentrator consists of an old damaged satellite dish, purchased from a scrap yard, and a polymer mirror film used as reflecting surface. The proposed concentrator is connected to a sun-tracking system which is based on an electronic circuit that processes the input signals from a set of sensors and drives the dish actuator. The solar thermal energy application to adsorption technology (with the sorption pair water/zeolite) is simulated using the ‘Ice-Quick’ device manufactured by Zeo-Tech GmbH. Samples from two types of zeolites were initially brought to saturation condition and then mounted on the focal point of the dish solar concentrator in order to be regenerated. Experimental results are presented and useful conclusions are drawn.     

浅析碟式太阳能发电技术

随着化石能源的大量开采,油价煤价不断上涨,充分利用太阳能显然具有可持续发展和节能减排的双重伟大意义。太阳能技术的大力推广在很大程度上缓解了能源问题。综合近年来国内外碟式太阳能发电技术,基于斯特林发动机,叙述了碟式／Stirling系统的构成、发电原理、发展现状,指出了目前存在的问题,提出了改善措施。     

Optimization of Output Power and Thermal Efficiency of Solar‐Dish Stirling Engine Using Finite Time Thermodynamic Analysis

This paper presents an investigation on finite time thermodynamic (FTT) evaluation of a solar‐dish Stirling heat engine. FTTs has been applied to determine the output power and the corresponding thermal efficiency, exergetic efficiency, and the rate of entropy generation of a solar Stirling system with a finite rate of heat transfer, regenerative heat loss, conductive thermal bridging loss, and finite regeneration process time. Further imperfect performance of the dish collector and convective/radiative heat transfer mechanisms in the hot end as well as the convective heat transfer in the heat sink of the engine are considered in the developed model. The output power of the engine is maximized while the highest temperature of the engine is considered as a design parameter. In addition, thermal efficiency, exergetic efficiency, and the rate of entropy generation corresponding to the optimum value of the output power is evaluated. Results imply that the optimized absorber temperature is some where between 850 K and 1000 K. Sensitivity of results against variations of the system parameters are studied in detail. The present analysis provides a good theoretical guidance for the designing of dish collectors and operating the Stirling heat engine system.     

Theory and performance analysis of a new heat engine for concentrating solar power

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.     

A parabolic dish/AMTEC solar thermal power system and its performance evaluation

This paper proposes a parabolic dish/AMTEC solar thermal power system and evaluates its overall thermal–electric conversion performance. The system is a combined system in which a parabolic dish solar collector is cascaded with an alkali metal thermal to electric converter (AMTEC) through a coupling heat exchanger. A separate type heat-pipe receiver is selected to isothermally transfer the solar energy from the collector to the AMTEC. To assess the system’s overall thermal–electric conversion performance, a theoretical analysis has been undertaken in conjunction with a parametric investigation by varying relevant parameters, i.e., the average operating temperature and performance parameters associate with the dish collector and the AMTEC. Results show that the overall conversion efficiency of parabolic dish/AMTEC system could reach up to 20.6% with a power output of 18.54 kW corresponding to an operating temperature of 1280 K. Moreover, it is found that the optimal condenser temperature, corresponding to the maximum overall efficiency, is around 600 K. This study indicates that the parabolic dish/AMTEC solar power system exhibits a great potential and competitiveness over other solar dish/engine systems, and the proposed system is a viable solar thermal power system.     

Development of thermodynamic cycles for concentrated solar power plants

Solar thermal power is a promising ‘green’ technology that could contribute significantly – in countries where it may be applicable due to available resources – towards meeting the 2020 and 2050 targets for the free energy production of emissions [Viebahn, P., Lechon, Y., and Trieb, F., 2011. The potential role of concentrated solar power (CSP) in Africa and Europe – a dynamic assessment of technology development, cost development and life cycle inventories until 2050. Energy Policy, 39 (8), 4420–4430]. Especially for the regions where solar radiation is significant, the technology of concentrated solar power (CSP) plants seems to have a great potential, once cost-related issues are resolved. The thermodynamic process, on which the component design of the plant is based, plays a significant role in the optimisation of the efficiency of the derived configuration. This paper aims to present a route for the design of thermodynamic cycles for a CSP, starting from the simplest processes and heading towards more complicated ones. For a reference output capacity, the obtained efficiencies are presented, illustrating the technical benefits of shifting to more advanced thermodynamic processes.