新能源和可再生能源在建筑中应用的意义和前景

1.建筑能耗简述 建筑物所用建筑材料的生产制造要消耗能源,建筑物的建设施工要消耗能源,建筑物在使用过程中更要消耗能源;一句话,建筑物从建设到使用都离不开能源,能源是建筑物建设和使用全过程不可缺少的、最为重要的物质基础。建筑能耗有两种定义方法:一种是广义建筑能耗,是指从建筑材料生产制造、建筑物建设施工一直到建筑物使用的全过程所消耗的能源;一种是狭义建筑能耗或称建筑使用能耗,是指建筑物在使用过程中所消耗的能源,     

基于温频法对北京延庆地区某建筑物的能耗分析

本文主要对北京延庆地区某建筑物的能耗特性进行研究,采用温频法对建筑物进行能耗分析,从而得到了该建筑物的热负荷。通过模拟值和实际运行值的对比可以得出:实际运行时,模拟值在运行数据附近变化,从而验证了模型的正确性。该模型对建筑物的能耗分析和采暖负荷计算具有一定的指导意义,可为整个双热源热泵系统的仿真及优化提供依据。     

第三步建筑节能对发展节能窗的机遇与挑战(上)

2004年7月1日北京市的<居住建筑节能设计标准>(节能65%)正式实施.该"标准"是在第二步节能设计标准(节能50%)的基础上,再节能30%.而且这部分节能率完全由提高建筑物围护结构的热工性能来实现,而不考虑靠采暖系统效率的提高来分担.建筑门窗是建筑物围护结构的重要组成部分,而且在整个建筑能耗中,经外窗的传热、辐射和空气渗透的热损失大约要占建筑物采暖能耗的一半左右,可见外窗对建筑节能的重要性.     

建筑节能技术探讨

由于建筑物的设计中有不合理之处,导致建筑物的空调负荷偏大,使建筑物增加了一部分不必要的能耗。建筑物里的空调系统设计方案也存在很多缺陷,使能耗过大。本文从建筑物和空调系统两方面进行分析,分别对建筑物及空调系统的节能技术措施进行了探讨。其主要节能技术措施有:使建筑物的规划设计科学、增强围护结构的隔热保温性能、使空调系统设计更科学合理、提高空调系统的管理意识。     

建筑节能

一、建筑能耗建筑能耗在社会总能耗中占有相当大的比重。建筑能耗主要包括四个方面:建筑材料、制品、设备的生产能耗;建筑施工、安装能耗;使用能耗和拆除能耗。使用能耗主要包括采暖、空调和热水供应能耗,其次是炊事、照明和家电能耗。由于建筑物的类别、规模、标准、结构体系、设备条件和使用年限的不同,建筑能耗之间的差别很大,而在建筑能耗中,使用能耗与其他能耗(如生产能耗、施工安装能耗及拆除能耗等)之比一般为9:1～8:2,因此建筑节能的重点应放在降低使用能耗上。     

能量计量应用过程中的问题凸现及对策

我国建筑能耗中采暖能耗是欧洲同纬度国家的3倍。推行建筑物能量计量,是保证能源利用效率达到最优的前提。本文论述了国内外的计量方法与应用程度,对我国供热计量收费改革进行了分析,强调建筑物能量计量是我国建筑节能的关键环节之一。     

高耗能建筑加剧电荒危机

世界各国对建筑节能非常重视，把降低建筑物能耗作为节能的基本有效措施，并制定了建筑节能法。有60多个国家和地区有用于新建筑的强制性节能标准，美国有40个州制订了本州的公共标准，其中有6个经济比较发达的州(如纽约州和加利福尼亚洲等)的建筑节能标准比国家标准更为严格。     

窗墙比和体形系数对办公建筑能耗的影响

济南地区某公共办公建筑,其围护结构按照高效节能的设计方法进行设计。运用Dest软件对该建筑进行能耗模拟,模拟该建筑的逐时能耗,分析不同体形系数和窗墙比对建筑物能耗的影响,以及两者共同作用下的影响。通过模拟结果得出:窗墙比对夏季负荷的影响要大于对冬季的影响,冬季窗墙比越大,能耗变化率相对较小;而体形系数的不同对建筑物空调能耗的影响变化较小。     

美国的能源利用

美国的能源市场潜伏着危机,国会采取果断措施降低能耗、调整工业产品结构、将先进技术渗入工业经济,使三大耗能领域的工业能耗、交通能耗、建筑物能耗明显下降,开始了能源与经济成非对偶关系发展的时期。     

西安市居住建筑能耗研究

随着我国建筑业的不断发展,建筑能耗占全社会总能耗的比例不断增大。与建筑相关的能源消耗包括建筑材料生产用能、建筑材料运输用能、房屋建造和维修过程中的用能以及建筑使用过程中的建筑运行能耗。在建筑的整个生命周期中。其建筑材料和建造过程消耗的能源一般只占总能耗的20％左右,而大部分能源消耗将一直伴随建筑物使用过程中发生。因此建筑的运行能耗。包括照明、采暖、空调和各类建筑物内使用电器的能耗。是建筑节能任务中最主要的关注点。本文所称的建筑能耗均指建筑运行能耗。     

预制舱类工业建筑能耗模拟软件PCES的设计与开发

  [目的]  建筑能耗模拟软件是建筑节能设计与建筑能耗评估重要的支持工具,而现行的建筑能耗模拟软件难以满足预制舱类工业建筑能耗分析及机柜级微环境控制设计的需求。  [方法]  提出了预制舱类建筑热平衡模型,基于该物理模型开发出预制舱类建筑能耗计算软件PCES,通过工程案例证明了PCES能客观地反映建筑物的能耗分布规律。  [结果]  计算表明:PCES可以实现对预制舱建筑围护结构、舱内热状况以及机柜级热环境状况进行求解,适用于工程节能设计与能耗分析。  [结论]  研究成果可实现建筑参数设定、能耗模拟与建筑热过程及能耗分析。     

全户内变电站装配式建筑墙体细化设计与应用

  [目的]  为促进变电站建设的规范、统一，提高建设效率，国家电网编制了通用设计并推广装配式建筑。在应用通用设计时简单套用标准图集，对具体工程可能会造成不必要的浪费，必须针对工程项目实际，结合建筑材料的发展，进行优化和细化设计。  [方法]  结合工程实例，根据功能需要和建筑材料性能，在满足结构、功能要求前提下，按照建筑、节能降噪、防火等要求，对全户内变电站装配式建筑墙体进行优化和细化设计研究，经过计算，确定了墙体构造、用材、厚度等具体设计参数。  [结果]  研究表明:细化设计方法通过多项工程实例检验，细化设计后节省了建材，节约了建筑占地，达到了节能目的。  [结论]  提出的细化设计方法可为同类工程设计和建设管理者提供借鉴和参考，值得推广应用。     

居住建筑固定资产投资项目节能评估中综合能耗计算方法的分析与比较

结合工作实践,发现西安市居住建筑类项目存在不同评估单位计算的年综合能耗量数值差异很大的现象,经比较分析发现差异的主要原因是建筑物采暖耗能量评估计算依据的标准规范不一致。通过对比两种计算方法的内容与指标,认为《城镇供热管网设计规范》采暖热负荷推荐值与项目具体建筑物体形系数、热工性能参数等数值无关,对单体建筑物而言不具有针对性,不是唯一的。因此,建议以《严寒和寒冷地区居住建筑节能设计标准》为节能评估计算依据,方符合国家推行固定资产投资项目节能评估与审查的目的。     

城市建筑冷热电能源提供模式的探讨

21世纪能源以及环境问题已经成为了各国的头等问题。我国建筑耗能的数字非常惊人：在建造和使用过程中直接消耗的能源占全社会总能耗的20%。根据发达国家的发展经验,这一比例将逐步提高35%左右,建筑能耗极有可能在不远的将来成为我国第一耗能大户。本文介绍了城市建筑中提供冷热电能量的四种方式。结合作者自身能源审计的经验比较了传统的中央空调加锅炉供能系统、分布式三联供系统以及地源热泵、太阳能供能的新能源供给系统的能效与减排量。得出了传统的能源供给系统虽然操作简单但是比较耗能而且排出的有害气体较多,三联供系统受天然气价格影响偏大,太阳能、地热能如不受限制应该尽可能运用的结论。最后笔者提出了我国建筑节能的设计方法以及发展前景。     

Overview of rural building energy efficiency in China

Over the past three decades, people׳s living standard in China has been greatly improved, accompanied by the rapid increasing building energy consumption. Rural building energy consumption has become one of the most important parts of the total energy consumption in China, which deserves to be paid much attention. It is of vital importance to promote building energy efficiency for the New Socialist Countryside and energy conservation and emission reduction. This paper provides an overview of building energy consumption in the countryside, which figures out the situation and challenges in energy-saving work. The government has worked for years on rural building code system aimed at narrowing the energy gap between urban areas, but it is in the beginning phase. This paper has analyzed the only special issues about rural building energy efficiency and the mandatory standards for urban buildings, which can facilitate the development of rural building energy efficiency. Based on the above analysis, some recommendations regarding the improvement of rural building energy efficiency are given.     

Setting the standard? A framework for evaluating the cost-effectiveness of building energy standards

The adoption rate and stringency of building energy standards in the U.S. have been increasing since the mid-1990s as a result of the Energy Policy Act mandate of 1992 (EPAct). Current evidence on the energy savings that accrue from commercial building energy standards is based on engineering simulations, which do not account for realized behaviour once a standard is actually adopted. This paper uses quasi-experimental variation in commercial building energy standard adoptions to estimate their effect on realized electricity consumption and cost-effectiveness. In states induced by EPAct to adopt an energy standard where all new nonresidential construction was erected under a commercial standard, electricity consumption per service worker is lower by about 12%, and total commercial electricity consumption is lower by 10%. Including early adopters and never-adopters to the analysis leads to a downward bias in the treatment effect. The realized electricity savings in the EPAct states represent three quarters of predicted simulated savings, and electricity saved in 2010 came at a cost of approximately 7.7 cents per kWh.     

Thermal and environmental assessment of a passive building equipped with an earth-to-air heat exchanger in France

In France, where a division by 4 of the greenhouse gases emissions is aimed from 1990 to 2050, technical solutions are studied in order to reduce energy consumption while providing a satisfactory thermal comfort level in buildings. A two-dwelling passive building has been carried out in Formerie (North-West of France), complying the “Passivhaus” standard. This building, not yet monitored, has been modeled using the dynamic simulation software COMFIE, which is dedicated to building eco-design. In order to account for the implemented ventilation system, including a heat recovery unit and an earth-to-air heat exchanger, a specific model has been developed and integrated to COMFIE as a new module. In this article, this model is described first. In order to quantify the benefits brought by a passive design, the simulation results are presented for the passive house and a reference house complying with the French thermal regulation for buildings. The heating load and thermal comfort level of both houses are compared, showing for the passive design a tenfold reduction of the heating load and a clear reduction of summer discomfort. Finally, the environmental assessment – carried out with the life cycle assessment tool EQUER – shows the reduction in primary energy consumption, global warming potential and other impacts brought by the passive house design. Passive house appears to be an adequate solution to improve the environmental performances of buildings in the French context.     

The use of CHP and absorption cooling in cold storage

In recent years, it has become standard practice to consider combined heat and power (CHP) systems early in the design stage of commercial buildings. With new initiatives from the UK government on reduced energy use, energy efficient systems such as CHP have been considered for a wider application particularly within industrial building design. The viability of CHP in a typical cold storage application is described in this paper. The electrical energy and heating requirements are defined and used to assess the annual energy consumption of a traditional cold storage design using a thermal model. The analysis is then used to consider the economics of different CHP configurations, which includes an integrated CHP and absorption system used to provide chilled glycol for the cold storage facilities. The additional capital cost of each configuration is shown and this is used to calculate the payback period. The results show that an attractive payback period of approximately four years for a combined CHP and absorption system may be achieved.     

Analysis of energy saving optimization of campus buildings based on energy simulation

The energy consumption of campus buildings has specific characteristics, because of the concentrated distribution of people’s working time and locations that change in line with distinct seasonal features. The traditional energy system design and operation for campus buildings is only based on the constant room temperature, such as 25°C in summer and 18°C in winter in China, not taking into consideration the real heating or cooling load characteristics of campus buildings with different functions during the whole day and whole year, which usually results in a lot of energy waste. This paper proposes to set different set-point temperatures in different operation stages of public and residential campus buildings to reduce the heating and cooling design load for energy station and total campus energy consumption for annual operation. Taking a campus under construction in Tianjin, China as an example, two kinds of single building models were established as the typical public building and residential building models on the campus. Besides, the models were simulated at both set-point room temperature and constant room temperature respectively. The comparison of the simulation results showed that the single building energy saving method of the peak load clipping could be used for further analysis of the annual energy consumption of campus building groups. The results proved that the strategy of set-point temperature optimization could efficiently reduce the design load and energy consumption of campus building groups.     

Building energy saving potential in Hot Summer and Cold Winter (HSCW) Zone,China—Influence of building energy efficiency standards and implications

Hot Summer and Cold Winter (HSCW) region plays an important role in China's building energy conservation task due to its high consumption in recent years for both climate and social reasons. National and local building energy standards according to which the buildings are built and operated can affect the building energy consumption to a great extent. This study investigated the energy saving potential in Hot Summer and Cold Winter Zone under different level of energy efficiency standards (China local, China national, and UK standard). Chongqing was taken as an example, and the commercial energy simulation tool eQuest was applied to analyze the building end-use energy. With the existing situation as a baseline, the building energy saving for residential section could achieve 31.5% if the Chinese national standard were satisfied, and the value would further increase to 45.0% and 53.4% when the Chongqing local and UK standard were met. For public buildings, the corresponding energy saving potentials were 62.8%, 67.4% and 75.9%. Parameter sensitivity analysis was conducted. The analysis was able to provide suggestions on energy saving implementation priorities for residential and public buildings. Indications to improve building energy standards and their implementation were also discussed.