Solar thermal applications in the West Indies

Solar thermal devices have been used in the West Indian islands for over a century. Traditionally, crops such as rice or cocoa have been dried in the sun on drying floors. In the last twenty five years solar water heaters have become commercially available and over 30,000 are now in use in Barbados and about 2000 in Jamaica. Solar stills and solar crop dryers have also been deployed and solar collectors have been used to power solar cookers and adsorption chillers. Compound parabolic concentrating solar collectors have been used for experimental purposes but the high level of diffuse radiation obtained during most months of the year makes concentrating collectors unsuitable.     

Design,development and testing of a novel non-tracking solar cooker

A novel solar cooker that does not require any tracking, has been designed, fabricated and tested and its performance has been compared with the hot-box solar cooker. The performance of the novel solar cooker is almost similar with the hot-box solar cooker though it is kept fixed while the hot box is tracked towards the sun every hour. The overall efficiency of the novel solar cooker has been found to be 29·5%. The payback period varies between 1·30 and 3·29 years depending upon the fuel it replaces. The payback periods are in the increasing order with respect to fuels such as firewood, coal, electricity, kerosene and LPG. The short payback period shows that the use of the novel non-tracking solar cooker is economical. © 1998 John Wiley & Sons, Ltd.     

Multiple use communal solar cookers

Solar cooking in boarding schools and communal centres in isolated areas demands the heating of large quantities of food. It is generally done in large pots of 30–40 litres. In a previous paper (Saravia et al., Energías Renovables y Medio Ambiente, ASADES, 1999, 6, 7–16), the solar cooker presented consisted of two separate units: a concentrator on one side and an insulated box containing the pot on the other. In this paper we introduce some changes which improve its working capacity. At present we can count on three different kinds of absorbers, which have been optimised to fulfill different functions in a concentrator of an area of 2 m². These alternatives allow the possibility of satisfying the needs of a communal dining centre, cooking for up to 30 children, once each concentrator has been installed.     

基于分光谱利用的新型塔式热-光伏复合发电系统的发电量预测

提出一种利用分光谱技术的塔式热-光伏复合发电系统,介绍系统的组成和结构。采用MUUEN算法设计镜场排列,在AM1.5D太阳光谱作为入射光时对提出的系统进行光学和热力学分析。采用拉萨典型气象年的太阳辐射数据,预测常规光伏发电、常规光热发电和本系统的全年发电量并进行对比。结果表明,在选定的气候条件下塔式分光谱热-光伏复合系统的综合发电量高于其他两种系统。     

Using renewable energy technologies for domestic cooking in India: a methodology for potential estimation

An attempt has been made to estimate the potential of using biogas plants, solar cookers and improved cookstoves for domestic cooking in India. Based on 1991 statistics on the bovine population and ownership pattern, the potential number of family size biogas plants comes out to be around 38 million in the optimistic scenario whereas, in the realistic scenario it is around 29 million. The potential of improved cookstoves is estimated at about 90 million and that of solar cookers is estimated at about 75 million.     

太阳集热器性能测试试验系统

在太阳跟踪精度，流量测量控制精度和温度测量控制精度满足条件的情况下，通过压力降落试验，时间常数试验，稳态效率试验以及入射角修正系数试验，测试太阳集热器的综合性能。     

Performance and testing of large-size solar water heater cum solar cooker

The performance of a novel device has been tested. The device can be used as a collector cum storage type solar water heater during the winter, and, with minor adjustments, it can be used as a hot-box solar cooker. The device can provide hot water at 50–60°C in the evening, which can be maintained at 40–45°C until the following morning. It can also be used for cooking food for about 40 people. The efficiencies of the device as a solar water heater and as a solar cooker have been found to be 67.7% and 29.8%, respectively. The payback period varies between 1.64 to 5.90 years depending on the fuel it replaces. The payback periods are of increasing length with respect to the fuels firewood, coal, electricity, LPG and kerosene.     

Performance test of a box‐type solar cooker: effect of load on the second figure of merit

In this paper thermal performance test experiments for first figure of merit (without load) and second figure of merit (with load) of a box‐type solar cooker were conducted as per Bureau of Indian Standards. The values of second figure of merit (F₂) were determined for different loads of water and the results show that F₂ depends on the quantity of water loaded in a solar cooker. Therefore, it is recommended that the performance test method should specify the amount of water which is to be taken. Copyright © 1999 John Wiley & Sons, Ltd.     

聚光太阳能SCO2热发电系统性能分析与优化设计

针对聚光太阳能超临界二氧化碳（SCO₂）热发电系统展开研究,构建系统热力学性能分析模型,分析集热侧、动力循环侧的性能,揭示系统集热-蓄热-热功转化之间的相互匹配特性规律,综合分析比较不同集热器、储热工质、动力循环组成的聚光太阳能SCO₂热发电系统的全年发电量和年均光-电转化效率,并对系统参数进行优化设计。结果表明：与线性菲涅尔式、槽形抛物面式聚光方式相比,塔式聚光方式的集热量受季节影响小,单位面积上全年集热量最高,全年集热效率约43%;增大高温储罐工质温度或降低低温储热罐工质温度能增大系统年发电量与年均光-电转化效率;采用塔式集热、NaCl-KCl-MgCl₂高温熔融盐、再压缩式超临界CO₂循环的聚光太阳能热发电系统具有最佳热力学性能。     

盐梯度太阳池Kalina循环发电系统性能研究

Kalina循环发电系统是一种典型的低温热源发电系统,具有广阔的应用前景。盐梯度太阳池能够实现连续聚热和跨季节蓄热,可广泛应用于光热发电系统和光热供热系统。文章提出了一种以太阳池储热量为热源的盐梯度太阳池Kalina循环发电系统,并利用Aspen Hysys软件对该系统进行建模。而后根据模拟结果,研究了提热温度、运行压力和氨水浓度对该系统各项性能的影响。此外,还分析了典型工况下,该系统的热力性能。分析结果表明:随着提热温度逐渐升高,盐梯度太阳池Kalina循环发电系统的发电功率、热效率和效率均逐渐增加;随着运行压力逐渐升高,该系统的热效率和效率逐渐升高,并且存在最佳的运行压力1.75 MPa,使得该系统获得最大发电功率;随着氨水浓度逐渐增大,该系统的发电功率也会逐渐增大,但热效率和效率却逐渐降低;当氨水浓度为85%、运行压力为1.75 MPa、提热温度为90℃时,该系统的热效率和效率分别为7.93%,57.59%。     

AA-CAES+CSP系统性能及关键参数分析

为深入分析耦合太阳能辅热的先进绝热压缩空气储能(AA-CAES+CSP)系统的运行特性,在先进绝热压缩空气储能(AA-CAES)系统基础上建立相关模型,对比分析这2个系统性能,并探究关键参数对AA-CAES+CSP系统性能影响.结果表明:相比于AA-CAES系统,AA-CAES+CSP系统循环效率提高7.90％,储能密...     

高效单晶硅太阳电池的研制

简述了高效单晶硅太阳电池的初步研制结果。对电阻率不同的ＣＺ和ＦＺ材料和不同的电池结构进行了实验。为了提高效率，对发射区钝化工艺、分区轻（ｎ＾＋）重（ｎ＾＋＋）扩散、背场、表面织构化技术和氯清洗等工艺进行试验研究。目前制备的最好电池，其效率为１８．６３％。     

厘米级涡喷发动机热力性能试验研究

为分析微型涡喷发动机核心机部件工作特性和整机热力性能,在发动机主要站位布置了温度和压强传感器,通过稳态试车试验测量工质热力状态参数,结合转速、流量等工作性能参数分别开展部件及整机热力性能计算.研究表明,燃烧室传热造成压气机效率下降,而散热损失和排气离速损失是影响微型涡喷发动机整机热效率的主要因素.在紧凑型涡喷发动机中,...     

再压缩sCO2 CPG联合循环热力优化

将CO_2地质封存与地热能开采相结合,利用CO_2羽流地热(CPG)系统开采超临界CO_2(sCO_2),并通过再压缩sCO_2布雷顿循环进行发电。建立了以太阳能为辅助热源的再压缩sCO_2布雷顿循环-CPG联合发电系统模型,研究了两类参数对联合发电系统性能的影响,并根据遗传算法进行全局参数优化以获得最大系统效率及最小度电耗sCO_2量。结果表明:再压缩sCO_2布雷顿循环-CPG联合发电系统具有较高的热效率,其中,主压缩机入口压力与分流比是影响系统热力学性能的主要参数,通过设计参数优化,系统效率可高达18.47%,度电耗sCO_2量减小至60.31 kg/(kW·h)。     

太阳能利用的发展概况和未来趋势

在简述太阳能利用技术和资源背景基础上,介绍国内外太阳能光伏发电及太阳能热利用技术和产业发展概况,并对本世纪太阳能利用技术的发展趋势和前景进行讨论。