太阳能空调制冷技术

太阳能用于空调制冷,最大的优点是季节匹配性好.利用太阳能实现制冷效应有多种技术途径,其中将太阳辐射转变为热能,通过热能实现制冷的方式最具有应用前景,特点是能够实现太阳能供热、空调综合利用,全年综合转换效率高.针对常见的太阳能热能转换制冷空调方式,从太阳能集热转换、匹配制冷循环选择、最新研究进展等方面进行了分析介绍.     

太阳能制冷讲座(1) 太阳能空调制冷技术

太阳能用于空调制冷,最大的优点是季节匹配性好。利用太阳能实现制冷效应有多种技术途径,其中将太阳辐射转变为热能,通过热能实现制冷的方式最具有应用前景,特点是能够实现太阳能供热、空调综合利用,全年综合转换效率高。针对常见的太阳能热能转换制冷空调方式,从太阳能集热转换、匹配制冷循环选择、最新研究进展等方面进行了分析介绍。     

太阳能集热-辐射制冷复合表面及其试制与性能分析

提出一种可以兼顾太阳能集热和辐射制冷的光谱选择性复合表面,其在太阳辐射波段(0.2~3.0μm)和辐射制冷"大气窗口"波段(8.0~13.0μm)具有高吸收(发射)率,而在除此之外的其余波段(3.0~8.0μm、13.0~25.0μm)具有低吸收(发射)率。笔者初步实现该复合表面的制备,对样品进行光谱测试表明其在太阳辐射波段和"大气窗口"波段的平均吸收(发射)率分别为0.92和0.80,其余波段平均吸收(发射)率为0.55,具有一定的光谱选择性。通过实例计算,对该复合表面与单独太阳能集热表面、单独辐射制冷表面和理想复合表面之间在太阳能集热效率、辐射制冷平衡温度和辐射制冷功率等关键性能参数进行对比分析。     

某大型商业综合体高效制冷机房实施技术路径研究

引入高效制冷机房是暖通空调节能的有效途径。高效制冷机房对设计优化、高效选型、BIM施工、能耗平台监测、调适运维等全流程阶段进行精细化管理,从而实现全生命周期内全负荷工况下机房所有设备的最佳匹配运行。通过分析机房系统能耗,阐述高效机房评价指标,最终得到高效机房实施的技术路径。结果显示：高效制冷机房能效比(EER)达到5.0,比常规制冷机房节能20%以上,节能降碳节能效果显著。     

用于低温储粮的太阳能吸附式制冷系统

提出并构建了一种用于低温储粮的太阳能吸附式制冷系统。利用该系统在中央储备粮某直属粮库进行了低温储粮实仓实验。实验测试结果表明,在16~21MJ/m2的太阳辐射条件下,该系统能够平稳地向粮仓输送14~22℃的冷空气,系统的日平均制冷功率约为3.25~4.43kW,太阳能制冷系数约为0.096~0.131,包括粮仓送风风机功耗的电制冷系数约为2.03~2.77。与目前的谷物冷却机相比,太阳能制冷低温储粮系统具有较大的节能优势。     

影响压缩式热泵制冷COP的因素分析

热泵系统可以将低品位能量加以利用,是一种节能环保的能源利用方式,但热泵的制冷经济性受能效比COP的影响很大,所以分析影响COP值的因素对设计高效热泵有一定的参考价值。本文在制冷工况下对影响压缩式热泵COP的温度、流量、负荷等因素进行分析,并通过举例说明,得到各因素对热泵制冷能效比的影响规律。     

城市热网夏季分布式吸收式供冷方式的能效与经济性分析

针对城市夏季热负荷需求较小集中供热资源闲置的问题,提出夏季利用城市热网驱动吸收式制冷机组的分布式供冷方式。采用一次能源节能率方法对比分析该种供冷方式与常规电制冷方式的能效差异;通过临界热价指出分布式吸收式供冷方式的经济性。深入分析了热电联产系统的发电效率和供热效率、全国平均发电效率、制冷机组的性能系数等因素对分布式供冷方式的节能性、经济性和适宜性的影响。研究表明城市热网夏季分布式供冷方式不具备明显的节能效益和较大的经济效益空间。同时指出与溶液除湿系统联合使用可以改善城市热网夏季分布式供冷方式的节能性和经济性。     

溴化锂蒸汽制冷在宝钢应用的可行性研究

针对宝钢低压蒸汽系统夏季余热蒸汽大量放散的问题，对增加夏季蒸汽负荷进行了可行性方案的研究。通过比较采用澳化锂蒸汽制冷取代电制冷的相关热力参数，可发现发展澳化锂蒸汽制冷实现热电冷三联产，不仅可以提高宝钢热电系统的热经济性，也可以降低宝钢夏季蒸汽放散量和电网的峰谷差，从而达到节电、节能、减少环境污染的目的。     

中央空调制冷系数与制冷主机节能研究

通过水冷式电动中央空调制冷系数的分析研究，对“制冷机组的制冷能力随蒸发温度的提高而提高，随冷凝温度的升高而降低”的理论提出质疑。分析制冷系数与工质的质量循环量以及蒸发温度、冷凝温度之间的关系，分析了在不对主机进行改造的前提下实现中央空调系统节能的可行性。     

基于TSI地基云图的云量反演方法研究

基于金昌地区全天空成像仪(TSI-880)观测资料,进行地基云图还原,并根据样本统计分析得到合理的红蓝比阈值(0.84)来区分云和晴空,构建批量云图还原与云量计算自动化系统。结合该地区光伏电站辐射观测站的太阳辐射资料,将系统计算的云量(修正云量)和TSI自行分析结果(原始云量)分别与太阳辐射资料进行对比。结果表明原始云量与太阳辐射衰减相关系数为0.3,修正云量与太阳辐射衰减相关系数为0.88,具有更好的相关性。这对于太阳辐射临近预报有重要意义。     

高空飞艇薄膜太阳电池内辐射量计算研究

修正了任一方向的平面内太阳辐射计算模型,使之适用于编程计算各种倾角和方位角平面上的太阳辐射。在曲面上进行网格划分,生成若干个小平面,推导出平面法向量与倾角和方位角之间的关系式,逐个计算每个小平面上太阳辐射量,叠加后近似代替整个曲面上的太阳辐射量。运用此方法计算了高空飞艇的薄膜太阳电池上辐射量,并与此薄膜太阳电池在水平投影面内辐射量计算结果进行比较。结果表明,用水平投影面内辐射量代替薄膜太阳电池内辐射量有很大的偏差。因此,在高空飞艇能源系统性能详细分析阶段需要使用曲面内太阳辐射量计算模型,为随后的光电转换与能源系统计算提供准确的太阳辐射数据。     

临近空间太阳能无人机能量调度策略

针对临近空间太阳能无人机因表面太阳辐射不均匀及负荷不确定性导致的能源系统容量无法充分利用的问题,提出一种实时能量优化调度策略,旨在最小化每个光储模块在24 h周期末电量差值、太阳落山时刻最大限度地储存能量,通过构建调度模型和能量前移修正策略达到充分利用发电、储能设备装机容量的目的。利用Python软件对该模型及调度策略进行仿真验证,证实了该能量调度策略的合理性和可行性。     

Transient heat conduction in a glass with chemically deposited SnS---CuxS solar control coating

The transient thermal performance of a chemically deposited thin film on a glass substrate is presented. Differential energy balances for the glass are set up assuming a one-dimensional transient state for normal incidence of the air mass to solar radiation. Using the reported properties of a SnS-Cu_xS thin film as a specific example, the net energy flow through a glass and the specific film were calculated for a time period. The effect of absorption in the film is specifically considered. The theoretical time histories of the surface temperatures of the glass plus solar control coating and the clear glass are plotted for an exterior temperature range of 0–50°C. The redistribution to the interior and exterior of the absorbed component of the solar radiation as well as the shading coefficient in time are evaluated for a constant convective heat transfer coefficient for ambient temperatures of 30 and 20°C. Also, the time constant of the system is given.     

临近空间太阳电池模型修正与发电量预测研究

由于在飞行过程中,温度、辐照度和倾角变化都会对临近空间飞行器上太阳电池的输出功率及效率产生影响,该文利用太阳光模拟器及薄型晶体硅太阳电池,进行多组测量实验,得到在不同温度、辐照度和倾角条件下,太阳电池的短路电流、开路电压等参数,并通过与模型仿真结果进行对比,对已有太阳电池电模型进行修正,得到更接近真实飞行工况的临近空间飞行器用薄型晶体硅太阳电池的模型。最后,基于修正后的模型通过仿真对太阳电池阵列在临近空间的全天发电功率变化趋势进行预测,可为临近空间飞行器用太阳电池阵列设计与功率预测提供重要参考。     

Solar cars free of environmental pollution—prototype of practically usable car completed

As a specific embodiment of the application of photovoltaic (solar) cells, the author has been engaged for 15 years in the development of electric vehicles charged by photovoltaic cells. This paper describes results of these developments. In this system, main photovoltaic cells were installed on the roof of a private house, and sub-photovoltaic cells were mounted on the roof of an electric vehicle. Electric energy thus obtained was used in charging a secondary battery mounted on the electric vehicle. Flexible, light and thin film a-Si photovoltaic cells were developed. These cells can be stuck to a curved surface and hence applied to solar battery cars.     

The novel usage of spectroscopic ellipsometry for the development of amorphous Si solar cells

We present the novel use of spectroscopic ellipsometry (SE) for the development of a-Si:H solar cell. SE is a very fast and useful tool to measure various optical properties of thin film. In the case of a-Si:H thin film analysis, generally, SE is used to estimate the film thickness, roughness, void fraction, optical constants such as (n,k), and so forth. In this study, optical parameters from SE measurements were analyzed with relation to structural and electrical properties of a-Si:H thin film for solar cell. By analyzing IR absorption spectra and conductivity measurements, it was affirmed that <ε₂> and parameter A by Tauc-Lorentz model fitting of SE data are representative parameters qualifying a-Si:H thin film, and that they have close relationships with FF and light induced degradation property of solar cells. Based on the analysis, solar cells that have i-layers with various E_g were optimized. By this research, easier and faster methodology to develop a-Si:H thin film for thin film Si solar cells using SE measurements was established.     

太阳光控膜的实验研究

采用金属反射膜和介质膜相结合的方法，研制了三种太阳光控膜系，即ＺｎＳ／Ａｇ，Ｉｎ２Ｏ３；ＳｎＡｇ和ＳｉＯ２／Ａｇ，并给出各自的光蛮     

Thin film angular selective glazing

Angular selective glazing based on special obliquely deposited thin films, has considerable potential for optimizing the overall performance of a window in temperate to hot climates. In contrast to most currently used glazings for these environments it has the ability to control solar heat gain and glare while providing a clear view through the window and considerable but not excessive light gain. Various deposition techniques and film materials will be discussed and the spectral and integrated optical performance of single and double-layered systems presented for various directions of incidence. Full optical characterisation requires measurements for incidence directions over half a hemisphere. Some of this is presented but most data is confined to planes of incidence where angular selectivity is greatest as determined by deposition geometry. Two layer systems are designed to provide a low emittance and better solar control than the single layer systems while retaining good visible angular selectivity. The single layers are primarily to provide angular selective control of the visual radiation since they have moderately high transmittance in the near infrared and a high emittance. Theoretical models used to extract structural information and model the complex optical properties are introduced and their predictions assessed. Preliminary results on simulation of the performance of full size angular selective windows in comparison to other types of solar control glazing such as low e heavily tinted windows are discussed in terms of their relative impact on cooling load, lighting contribution, glare control and total energy savings.     

Enhanced efficiency of thin film GaAs solar cells with plasmonic metal nanoparticles

In the present work, a thin film solar cell structure consisting of thin GaAs layer, metallic nanoparticle array and aluminum back reflector is proposed and studied to calculate optical absorption and current density using finite difference time domain (FDTD) numerical simulation method. Simulation results show that in comparison to other metallic nanoparticles, aluminum nanoparticles have strong plasmonic scattering effect at optimized period of 100nm and radius 40nm to improve the efficiency of thin film GaAs solar cells through enhancement of current density integrated over solar spectrum by 31% compared to bare thin film GaAs solar cells.     

不规则太阳电池临近空间发电模型构建与分析

临近空间长航时飞行器（平流层飞艇、太阳能飞机、高空科学气球等）是目前高空平台（HAPS）的一种发展趋势。目前临近空间长航时飞行器的能量来源主要是太阳电池,由于飞行器形状和体积不同,太阳电池安装位置和面积也不同。飞行器有效铺装面积有限,为了实现能量平衡,因需要铺装更大面积,会遇到不规则形状铺装的情形,但此时的发电预测计算过程比较复杂且速度较慢。该文提出一种基于太阳电池之间关系的发电模型,实现任意单块太阳电池快速预测光伏阵列发电功率。针对现有飞行器不规则铺设太阳电池的进行仿真分析,结果表明,该模型能够准确预测其发电能力,并解决了不规则太阳电池发电能力的准确预测计算过程复杂和速度较慢的问题,修正后的模型在计算用时效率上最多可减少50%。