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首座实用大型太阳能空调热水系统在我国研制成功刘启扬广西区农村能源办公室龚粹珍利用清洁、永恒的太阳能作能源，发展太阳能空调热水系统，具有一定的社会和经济效益。国家“九五”重点科技攻关项目——我国首座实用性大型太阳能空调热水系统由中国科学院广州能源研究所研制成功。该系统利用太阳能集热器产生热水，用热水作能源推动吸收式制冷机制冷；同时，孩系统也可以全年提供生活用热水，该系统包括500m’的太阳能平板集热器、两级吸收式制冷机等组成部分，制冷的热源温度为65℃左右，并完全进行自动控制。该系统具有热效率高、节能、…     

小型太阳能吸收式空调的运行特性和室内热舒适性试验

在夏季典型工况下,对一个小型太阳能吸收式空调系统进行了试验研究.试验系统主要包括:96 m2的真空管集热器、额定制冷量为8 kW的吸收式制冷机、容量为3t的热水储水箱、500 L蓄冷水箱以及50 m2冷辐射吊顶.试验结果显示吸收式制冷机的制冷量平均为3.9 kW,每天达到的平均制冷时间为10 h.分析了室内的热舒适情况...     

我国研制成功首座太阳能空调热水系统

中国科学院广州能源研究所1998年6月1日宣布,该所成功研制出我国首座实用性大型太阳能空调热水系统。 该系统利用500平方米太阳能平板集热器产生65C左右的热水作为热源,推动国际首创的两级吸收式制冷机制冷,全自动控制,能为600平方米整层楼房进行空调和全年提供热水,     

太阳能吸收式空调系统在别墅中的应用

根据别墅建筑的特点,建立一套太阳能与小型溴化锂吸收式制冷机相结合的制冷／热泵系统。该系统可为别墅建筑实现夏季制冷、冬季供暖以及全年提供生活用热水多项功能。介绍了整个系统的形式及其工作原理以及如何选择太阳能集热器和吸收式制冷机,并指出了系统的初投资较高、系统效率较低等不足;建议了提高制冷机制冷系数的措施以提高系统的总效率。     

模拟太阳能驱动吸收式装置的试验研究

报道了溴化锂吸收式制冷和供热两用装置在由模拟太阳能集热器提供的６７－７５℃热水驱动下，实施制冷循环及Ⅱ型热泵循环的试验研究结果。给出了驱动热水温度为定值及变值时吸收式装置的性能和经济指标随运转参数的变化关系，并分析了经济运行工况、制冷量与供热量间匹配关系及系统的节能效果。     

中高温热管式太阳能吸收式空调系统的设计与研究分析

太阳能空调技术中,太阳能单效溴化锂吸收式制冷空调技术是应用最多的一种,但小型太阳能吸收式空调系统存在不稳定及效率低的问题。本文主要通过对太阳能集热器选项及效率分析,低温驱动太阳能吸收式空调热物理参数分析,并完成实验测试,制冷采暖效果良好。     

太阳能氨水吸收式家用制冷空调的开发与应用

介绍太阳能集热器和氨水吸收式制冷机的结构、原理和特点,对利用太阳能驱动氨-水吸收式制冷空调的可行性进行分析探讨,阐述研制开发太阳能氨水吸收式制冷空调对节能降耗保护环境的意义.     

吸收式太阳能制冷空调系统的性能分析

介绍了一个吸收式太阳能制冷空调系统,该系统由太阳能集热器、吸收式制冷机组、辅助加热装置、智能控制器等部分组成。文章对该系统一年多的运行数据进行了采集和整理,针对夏季与冬季的典型工况进行了性能分析,并与常规空调进行了经济性对比,分析其投资回收期。     

太阳能供热采暖技术讲座(5) 太阳能供热采暖系统的设计(上)

<正>一太阳能供热采暖系统设计流程太阳能供热采暖系统是将太阳能转换成热能,供给建筑物冬季采暖和全年其他用热系统,系统的构成与太阳能热水系统类似。系统设计主要涉及以下内容:(1)系统选型;(2)太阳能集热器面积确定;(3)设备选型,如储热水箱、水泵、辅助热源等;(4)采暖、供热末端设计;(5)系统环境和经济效益分析。系统设计流程如图1所示。     

太阳能热水空调建筑一体化系统

设计了太阳能热水空调建筑一体化系统。该系统由2台冷水水冷机组、2个平板型太阳能集热器单元、1个贮热水箱、2个贮冷水箱和77台供冷终端组成,为海南省昌江县人民医院内儿科77个病房提供空调冷量和洗澡用热水。该系统初投资少,设备利用率高。经过1年的应用运行,取得了节约能源、减少对环境热污染的效果,为更好地推广应用太阳能探索一条新的路子。     

Parametric Analysis of Solar Heating and Cooling Systems for Residential Applications

Abstract

In this paper, a parametric analysis of two solar heating and cooling systems, one using an absorption heat pump and the other one using an adsorption heat pump, was performed. The systems under investigation were designed to satisfy the energy requirements of a residential building for space heating/cooling purposes and domestic hot water production. The system with the absorption heat pump was analyzed upon varying (i) the solar collectors’ area, (ii) the volume of the hot water storage, (iii) the volume of the cold water tank, and (iv) the climatic conditions. The system with the adsorption heat pump was evaluated upon varying (i) the inlet temperature of hot water supplied to the adsorption heat pump, (ii) the volume of the hot water storage, (iii) the volume of the cold water tank, and (iv) the climatic conditions. The analyses were performed using the dynamic simulation software TRNSYS in terms of primary energy consumption, global carbon dioxide equivalent emissions, and operating costs. The performance of the solar heating and cooling systems was compared with those associated with a conventional system from energy, environmental and economic points of views in order to evaluate the potential benefits.     

Influence of supply and return water temperatures on the energy consumption of a district cooling system

In a district heating and cooling system, for example, the Beijing combined heating, cooling and power (CHCP) system studied here, high temperature water generated by cogeneration plants circulates through a network between the plants and the heating substations. In heating substations, high temperature supply water from the network drives absorption chillers for air-conditioning in the summer, satisfies space heating demands in the winter and provides domestic hot water using heat exchangers throughout the year. This paper studies the significant effect of the parameters, i.e. the supply and return water temperatures in the network, on the CHCP system energy consumption for cooling and for domestic hot water.     

Modeling and simulation of solar absorption system performance in Beirut

An analytical study is performed on solar energy utilization in space cooling of a small residential application using a solar lithium bromide absorption system. A simulation program for modeling and performance evaluation of the solar-operated absorption cycle is done for all possible climatic conditions of Beirut. The results have shown that for each ton of refrigeration it is required to have a minimum collector area of 23.3 m² with an optimal water storage tank capacity ranging from 1000 to 1500 liters for the system to operate solely on solar energy for about seven hours a day. The monthly solar fraction of total energy use in cooling is determined as a function of solar collector area and storage tank capacity.An economic assessment is performed based on current cost of conventional cooling systems. It is found that the solar cooling system is marginally competitive only when combined with domestic water heating.     

Solar operated absorption air-conditioner for a Kufra house

The use of solar energy for domestic water heating and space heating has proved to be viable. Space cooling is another promising avenue for utilization of solar energy. Solar operated absorption air-conditioning systems, in different situations, have been found to be feasible. Such systems can make use of the expensive collectors which are, in any case, installed for water and space heating.

In this paper the cooling of a prototype house, in Kufra, is reported. Starting with measured radiation and ambient data, calculations are performed on an hourly basis to determine the cooling load, radiation in the collector plane, heat delivered by the collectors and the heat stored in or discharged from the storage tank. Three different types of collectors with varying efficiencies are considered. These collectors are of the evacuated tube, selective coated and black painted types. The study confirms that the water-lithium bromide absorption system can provide summer air conditioning in arid zones of Jamahiriya where there are diffuclties with the supply of electricity and fossil fuels.     

Experimental results of a sensible heat storage system for residential and light commercial application

This paper presents the performance results for a sensible heat storage system. The system under study operates as an air source heat pump which stores the compressor heat of rejection as domestic hot water or hot water in a storage tank that can be used as a heat source for providing building heating. Although measurements were made to quantify space cooling, space heating, and domestic water heating, this paper emphasizes the space heating performance of the unit. The heat storage system was tested for different indoor and outdoor conditions to determine parameters such as heating charge rate, compressor power, and coefficient of performance (COP). The thermal storage tank was able to store a full charge of heat. The rate of increase of storage tank temperature increased with outdoor temperature. The heating rate during a charge test, best shown by the normalized rate plots, increased with evaporating temperature due to the increasing mass flow rate and refrigerant density. At higher indoor temperature during the discharge tests, the rate of decrease of storage tank temperature was slower. Also, the discharge heating rate decreased with time since the thermal storage tank temperature decreased as less thermal energy became available for use. Copyright © 1999 John Wiley & Sons, Ltd.     

Feasibility study of a solar-assisted heating/cooling system for an aquatic centre in hot and humid climates

This paper reports on a feasibility study of a solar-powered heating/cooling system for a swimming pool/space combination in a tropical environment. The system utilizes an absorption chiller and a cooling tower to meet the facilities and locker room load. The heating is accomplished by employing hot water generated by heat exchange with the solar collector working fluid. Two thermal storage tanks were employed for the collector and domestic use. The absorption chiller utilizes hot water to regenerate the LiBr solution. The proposed system enables the swimming season to be extended from sixteen weeks to fifty-two weeks. Simulation results indicate that a combination of a double glazed collector area of 600–4800 m² and a storage tank volume of 11·36 m³ results in a 25–37% reduction in the consumption of natural gas. Economic analysis is performed based on the life-cycle-cost method and takes into account the effects of discount rate, fuel price and fuel inflation rate. Different scenarios for which the solar-assisted system is economical are presented and analysed. © 1997 John Wiley & Sons, Ltd.     

Performance analysis & energy benefits of a desiccant based solar assisted trigeneration system in a building

In this paper, performance details and operational benefits of a large scale solar trigeneration system that provides for solar assisted desiccant cooling, heating and hot water generation installed in a teaching institute building have been reported. A two-rotor desiccant system designed for handling 12 000 m3/hr of air was integrated into existing plant to provide a net reduction in energy consumption over the pre-existing heating ventilation and air-conditioning and domestic hot water systems. The system is controlled and monitored by a building management system which has been used to investigate and analyse the typical system behaviour. Heat from solar energy contributed consistently to reduce gas usage for water heating and on an annual basis showed a reduction of 21% of consumed energy. The solar energy contribution for space heating varied over winter months and during some months it was observed to contribute more than 50% of the total energy requirements for space heating. Under suitable ambient conditions, approximately 35% of total building cooling load was met by the solar driven desiccant cooling system. Continuous monitoring has also helped understand some of the operational issues of the system.     

A review for absorbtion and adsorbtion solar cooling systems in China

In the past decades, solar water collectors were installed for the main purpose of preheating domestic hot water or to cover a fraction of the space heating demand in China. However, solar cooling systems were constructed just for demonstration purposes. Since the building of the first solar-powered absorption cooling system in Shenzhen in 1987, there have been over 10 additional solar cooling demonstration projects constructed. In this paper, the most representative five projects including both absorption and adsorption cooling systems are introduced and summarized. From the demonstrations, solar absorption cooling systems have been shown to be more suitable for large building air-conditioning systems. Comparatively, solar adsorption cooling systems are more promising for small size air-conditioning systems. In order to attain high utilization ratio, it is highly recommended to design solar-powered integrated energy systems in public buildings. In addition, highly efficient heat pumps are considered as the most appropriate auxiliary heat sources for solar cooling systems, for the purpose of all-weather operation. In the 11th Five year research project (duration 2006–2010), solar cooling technologies will be further investigated to achieve a breaking through in the integration of solar cooling systems with buildings.     

EVALUATION OF THE DYNAMIC PERFORMANCE OF A HOT WATER TANK WITH BUILT-IN HEATING COIL

Hot water tanks with a built-in water-heating coil are commonly used in district heating house stations in Denmark for domestic hot water (DHW) production and storage. In this study, an evaluation of the dynamic performance of a hot water tank with built-in heating coil is carried out by applying a dynamic simulation programme which has been made previously, based on a simple dynamic model developed by the authors. System evaluation of the way in which system parameters, such as control valve size, heat loss coefficient of the DHW circulation pipe, position of the temperature sensor (for DHW temperature control) and fouling of the heating coil, affect the domestic hot water capacity and the average district heating water cooling for a given hot water tank is presented and discussed in this paper. The evaluation results show the importance of the correct design of the control valve size, the reduction of heat loss from DHW circulation pipes, the careful adjustment of temperature sensor position and temperature sensor set-point, and the reduction of the heat coil fouling growth rate in order to operate the hot water tank in an efficient way and to achieve significant cooling of the district heating water. © 1997 by John Wiley & Sons, Ltd.     

Status and prospects of local solar heating and cooling systems

In this paper, a state-of-the-art of solar heating and cooling systems is presented. Solar air heaters and different types of solar water collectors are discussed in detail. Storage systems including water, rocks, and heat-of-fusion salts are described as are space heating systems employing solar air heaters, in conjunction with rock or heat-of-fusion salt storage, and the use of water collectors plus hot water storage for space heating and domestic hot water. An indication of the commercialization of various space-heating systems and broad economic projections are presented. The three major solar cooling methods—absorption cooling, solar mechanical systems, and those involving humidification-dehumidification cycles—are also discussed in detail. Finally, an overview of solar heating and cooling activities in Kuwait is also given.