淡水太阳池

虽然太阳能具有可再生、无污染和共享用等优点，但其低密度、不稳定性和初投资高等缺点，大大限制了它的广泛利用。太阳池是一种既可收集又能贮存太阳能的装置，其特点是能长久、稳定、廉价地提供恒温热能。太阳池按其贮能介质可分为盐梯度太阳池和无盐太阳池，其中盐梯度...     

生态沼气池探讨

1　发展农村沼气存在的问题农村推广沼气一直是以解决炊事用能为主要目的,普遍采用6～8ｍ3的水压式沼气池,这种以解决一日三餐的炊事用能为主要目的的“能源沼气池”有很大的局限性,主要表现在:11　对大多数农户来说,要靠沼气解决全部的炊事用能是困难的,它受到发酵原料严重短缺的制约发酵原料是生产沼气的物质基础。从理论上讲,农村沼气资源十分丰富,但问题在于:1.不是所有沼气资源都能开发利用,这里既存在经济效益问题,也存在技术问题(例如以秸秆做沼气发酵原料就存在这些问题);2.从总体上讲农村的沼气资源可能是丰富的,但具体到每个农户…     

海岛独立能源发电站可视化监控系统的实现

建立海岛独立能源发电站是解决海岛能源短缺问题和促进海岛经济发展的措施.文章利用发电站的发电装置控制系统的DSP作为下位机,通过RS485进行数据传输,用VB设计了可视化监控界面,建立了上位机的监控系统,为发电站的高效、稳定运行提供了有力的保障.     

芒硝太阳池的研究与应用

该本对芒硝太阳池梯度区的浓度分布、温度分布以及芒硝太阳池的能量利用和应用进行了研究，并与实验结果进行比较，两者基本吻合，研究认为芒硝太阳池梯度区(非对流层)内温度分布，浓度分布是非线形的，利用太阳池技术为开发芒硝资源提供了一种新技术。     

双热源太阳池热泵技术的应用研究

对双热源太阳池热泵技术的应用进行了模拟研究.运用有限差分的方法,太阳池模拟结果表明,所储存的能量相对比较稳定,可为变负荷载荷供热;太阳池热泵技术的应用模拟结果表明,太阳池作为地位热源时,热泵制热的性能系数在4.08～4.87.若冬季太阳池作为低位热源的提热量为20 W/m2,完全能够满足冬季供暖时的温度要求.研究结果为实际利用提供了计算方法和重要依据.     

印度一家牛奶场的大型太阳池

印度古吉拉特邦普杰一家牛奶场的太阳池,设计容量达到每天能提供热水8万升,到目前为止已提供热水2000万升以上. 这是一座盐梯度太阳池,使用的太阳能集热器价格便宜,兼有储热功能,适合印度国情.     

辽宁沿海地区发展太阳池的前景

本文概述了目前国内外太阳池的研究状况,分析了辽宁沿海地区发展太阳池的自然条件和生产生活的需要,提出了辽宁沿海地区发展太阳池的些设想并作了一些初步估算。     

表层结冰对太阳池性能的影响研究

在对现有太阳池进行计算研究的基础上,针对目前北方太阳池冬季要经历结冰期这一现状,提出了表层结冰后太阳池辐射透射模型及热传导模型,将结冰情况考虑到太阳池的运行中,所提出的太阳池模拟计算中考虑了太阳池表面结冰对其整体性能的影响,为太阳池的长期连续性运行提供了研究基础.根据实际温度资料及气象条件,对结冰情况中太阳池的运行进行...     

无盐太阳池

太阳池是一种收集和储存太阳能的设施。普通的太阳池是一种含盐浅水池,其深度一般在1米以上,水池中盐溶液浓度从上层到下层逐渐增大,直到饱和,并呈梯度稳定状态,这样可以抑制对流散热。池的底部涂黑,以吸收太阳能。池与土壤接触的壁用良好的隔热材料隔热。吸收的太阳热能就储存在下层的水中。这种太阳池已经发展到实用化阶段,如以色列已     

太阳池的研究与应用

自从1902年Kalecsinsky首次发现了天然太阳池现象以后，经过长期的研究和发展，太阳池技术已被广泛应用于发电、取暖、海水淡化．矿物加工等领域，太阳池成为近期内进行大规模太阳能热利用的最有前景的低温热源装置。主要综述了太阳池的集热原理及建造方法、太阳池中热量的贮存及提取方式、太阳池的应用以及研究动向等，并指出目前我国太阳池技术还处于实验研究的阶段，而我国具有丰富的太阳能和盐资源，大力开发太阳池技术将为发展地方经济起到重要的作用。     

Study of an indian biogas plant with a water pond

To overcome the problem of reduced biogas production, due to low ambient temperatures during the winter months of northern India, a novel concept of a shallow solar pond (SSP) water heater has been put forward and studied theoretically. The pond is proposed to be integrated with the dome of the conventional Indian (KVIC) biogas design. The results of the study show that system is capable of providing hot water upto a temperature of 40°C which, in turn, can be used for hot charging of the slurry besides reducing the heat losses from slurry to the ambient. Simultaneously, it helps in enhancing the slurry temperature from 20°C to 27°C.     

The self-sufficient solar house in Freiburg

The Fraunhofer Institute for Solar Energy Systems has built a completely self-sufficient solar house (SSSH) in Freiburg, Germany. The entire energy demand for heating, domestic hot water, electricity, and cooking is supplied by the sun. The combination of highly efficient solar systems with conventional means to save energy is the key to the successful operation of the house. Seasonal energy storage is accomplished by electrolysis of water and pressurized storage of hydrogen and oxygen. The energy for electricity and hydrogen generation is supplied by solar cells. Hydrogen can be reconverted to electricity with a fuel cell or used for cooking. It also serves as a back-up for low temperature heat. There are provisions for short term storage of electricity and optimal routing of energy. The SSSH is occupied by a family. An intensive measurement program is being carried out. The data are used for the validation of the dynamic simulation calculations, which formed the basis for planning the SSSH.     

Field testing on nonsalt solar ponds

A new type of nonsalt solar pond was investigated by field testing. The roof of the solar pond was formed using a transparent double film. Three kinds of tests were carried out under the following conditions: (1) insulating pellets were packed between the layers of the transparent double film of the roof at sunset; (2) the water surface of the pond was insulated using only the two transparent films; (3) the water surface of the pond was covered by the double film with the top surface blackened on which solar energy can be collected, while pond water was circulated using a solar cell powered submerged water pump. The warm water stored in the solar pond by the above methods was utilized as a heat source for a gas engine powered heat pump used to heat a greenhouse. In this report, the results of the field tests on the above solar ponds and greenhouse heating system are discussed. Also the utility of a combination plant using a solar pond and underground borehole storage system is evaluated.Important conclusions on performance are as follows: (1) collection efficiencies of these solar ponds become 9–54% corresponding to the weather conditions and pond temperatures; (2) maximum temperature of the pond water under weather conditions at Osaka is about 80°C; (3) the solar pond can be effectively utilized for heating a greenhouse; (4) the combination plant using the solar pond and the underground storage layer can store heat of 1119 MJ m⁻² yr⁻¹.     

Conclusions from the Representative of the European Parliament

This article describes a co-generation plant based on the biogas being produced from the waste of distillery plant and highlights the possible configuration in which the plant can be hybridized with auxiliary solar energy source having the advantage of using financial incentives in several countries. In hybridization, the solar heat is used for heating the boiler feed water. The solar heat-generating unit consists of line focus parabolic trough collector, heat transportation system and heat delivery unit such as heat exchanger. The simulation model of heat and mass transfer processes in the solar field as well as the balance of the system is developed to investigate the technological feasibility of the concept in terms of plant yield and matching of subsystems.     

Heat loss reduction from the gas holder/fixed gas dome of a community-size biogas plant

The decrease in the yield of biogas in winter months in the usual systems—fixed dome and floating dome types—can be checked by providing insulation on the inner surface of the gas holder. A mathematical model has been developed to study the effect of putting in such insulation. A novel concept of making a shallow solar pond water heater over the gas holder to reduce the heat losses and simultaneously provide water for hot charging is proposed and analysed. Calculations corresponding to a typical winter day at New Delhi have been made for a numerical appreciation of the developed analysis.     

联合太阳能沼气的冷热电供能系统的集成及经济性分析

冷热电联供是一种先进、高效的能源系统,目前在我国应用的主要问题是天然气成本高,导致系统经济性差。太阳能和沼气是非常清洁的可再生能源,在我国来源广泛且廉价。将冷热电联供系统与太阳能、沼气完美地结合起来,集成为联合太阳能沼气的冷热电供能系统。该系统较为合理的组合方式是采用太阳能沼气池作为燃料提供装置,采用微型燃气轮机、余热锅炉、溴化锂吸收式制冷机、蒸汽换热器等作为供电、供冷和供热机组,采用太阳能集热器、换热器等装置为沼气池加热,太阳能不足时采用尾气加热。该系统能够实现能量的梯级利用,提高一次能源利用率,达到综合用能的目的,同时可有效治理环境。以某酒店作为该系统的用户对象,分析其经济性并与常规模式进行对比。结果表明,该系统一次能源利用率为74.8%,而常规模式为62.3%;综合能源价格为0.3398元/(k W·h),而现阶段电网电价约为0.6元/(k W·h);环境与减排评价指标也具有明显优势。     

Solar pond with honeycomb surface insulation system

A solar pond consisting of transparent compound honeycomb encapsulated with Teflon film and glass plates at the bottom and top surface respectively, floating on the body of a hot water reservoir is considered and analysed for the heat transfer processes in the system. A mathematical model is developed where the energy balance equation of the convective water is formulated by considering its capacity effects, various heat losses and solar energy gain through the surface insulation and is solved by the finite difference method. Transient rate of heat collection and storage characteristics are investigated. Explicit emphasis is laid on the effect of the thickness of the bottom encapsulation on the year-round thermal performance of the system and results seem to favour the minimum thickness. The annual average efficiency of the transparent honeycomb insulated solar pond is found to be higher than the conventional salt gradient pond by a factor of about 2.     

Saturated solar ponds: 1. Simulation procedure

The mass and energy balances on the upper convective zone, nonconvective zone, and lower convective zone of a saturated solar pond are written to yield a set of nonlinear partial differential equations. These are solved numerically to predict the thermal performance of the pond over a long period of time for various initial and boundary conditions. This model considers external parameters such as hourly variation of incident solar radiation, ambient temperature, air velocity, and relative humidity. Temperature and concentration dependence of density, thermal conductivity, specific heat, and mass diffusivity are taken into account. Heat transfer modes considered between the upper convective zone and the ambient are convection, evaporation, and radiation. Ground heat losses from the lower convective zone are also considered. This model is used to study the development of temperature and concentration profiles inside a saturated solar pond. This model can also be used to predict the long-term performance of a saturated solar pond for various heat extraction temperatures and rates.     

Performance assessment of a magnesium chloride saturated solar pond

This paper deals with the experimental investigation of a magnesium chloride saturated solar pond and its performance evaluation through energy and exergy efficiencies. The solar pond system is filled with magnesium chloride containing water to form layers with varying densities. A solar pond generally consists of three zones, and the densities of these zones increase from the top convective zone to the bottom storage zone. The incoming solar radiation is absorbed by salty water (with magnesium chloride) which eventually increases the temperature of the storage zone. The high-temperature salty water at the bottom of the solar pond remains much denser than the salty water in the upper layers. Thus, the convective heat losses are prevented by gradient layers. The experimental temperature changes of the solar pond are measured by using thermocouples from August to November. The densities of the layers are also measured and analysed by taking samples from at the same point of the temperature sensors. The energy and exergy content distributions are determined for the heat storage zone and the non-convective zone. The maximum exergy destructions and losses appear to be 79.05 MJ for the heat storage zone and 175.01 MJ for the non-convective zone in August. The energy and exergy efficiencies of the solar pond are defined as a function of solar radiation and temperatures. As a result, the maximum energy and exergy efficiencies are found to be 27.41% and 26.04% for the heat storage zone, 19.71% and 17.45% for the non-convective zone in August, respectively.     

带有透明蜂窝漂浮式选择性吸热器的小型净水太阳池数值模拟分析

提出了一种低热损小型净水太阳池，采用带光谱选择性吸收面的漂浮式吸热器及透明蜂窝结构，可大幅度抑制热损。工作时，从池底抽出的水喷射在吸热器的背面，能使后者恒处于较低的温度，基于一维准稳态假定提出一个计算模型，可用于计算一天中池水温度随深度的变化及一年中各月份的的热性能。