Thermal dynamic transfer properties of the opaque envelope: Analytical and numerical tools for the assessment of the response to summer outdoor conditions

The reliable estimation of buildings energy needs for cooling is a crucial issue in the implementation of the EPB Directive 2010/31/EU (formerly 2002/91/EC), especially in central and southern Europe climates. On this purpose one of the main topics is to predict the behavior of the opaque envelope subjected to variable boundary conditions. The EN ISO 13786:2007 technical standard assumes sinusoidal boundary conditions and introduces dynamic thermal characteristics.The aim of this paper is to assess the deviation arising by the use of different approaches for the calculation of the dynamic thermal characteristics of an opaque envelope element under periodic non sinusoidal boundary conditions. The EN ISO 13786 procedure has been firstly applied by decomposing the external forcing temperature by means of the Fast Fourier Transform (FFT) analysis. A comparison with different approaches, such as Finite Difference Methods (FDM) and Transfer Function Methods (TFM), has been carried out.The predictions of the EN ISO 13786 with a sinusoidal forcing temperature (i.e., standard approach) have also been assessed, comparing the results to the ones obtained through the FFT analysis. Furthermore, corrections to the periodic thermal transmittance and to the time shift have been proposed, in order to improve the explicative worth of those parameters.     

Macroeconomic effects of energetic building retrofit: input-output sensitivity analyses

Energy efficiency measures in buildings are essential for climate protection, but are not always recognized by the investor in common profitability calculations. To provide a quantitative scientific base for policymakers, the aim is to identify and quantify the impact of these measures on Germany’s economy with a static open input-output model. Moreover, this investigation analyses how much the chosen base year affects the calculated macroeconomic impact, to obtain a clearer view of involved dynamics. The energy efficiency measures in buildings and their impact on energy demand and investments were simulated in the bottom-up building model INVERT/EE-Lab up to 2020. The methodological addition of this research is to identify and map the resulting impulses to the according macroeconomic sectors. Based on this stimulus a static input-output analysis is conducted using a range of base years. The results show that efficiency measures in buildings have a significant positive effect on macroeconomic key figures. The magnitude of the calculated impact depends on chosen base year data and varies for value added and employment. As a conclusion, the macroeconomic impact constitutes a co-benefit supporting the economic attractiveness of energy efficiency. However, studies based on a single base year dataset like many computable general equilibrium models may need to reflect the errors caused by that choice.     

面向方案阶段能耗主导的建筑性能快速优化方法

依托机器学习和参数化技术建立了面向建筑方案设计阶段能耗主导的建筑性能快速优化方法,从而实现方案设计阶段以能耗为代表的建筑性能的直观呈现.本文通过实际案例证实了将建筑能耗快速计算技术与交互式性能优化框架相结合,可以让建筑师在进行方案推进与决策过程中直观而快速地获取以建筑能耗为代表的各项性能指标的反馈,从中选择最佳的设计方案,提升建筑师进行性能优化设计的能力.     

我国住宅建筑节能潜力分析——除供暖外的住宅建筑能耗

城镇民用建筑能源消耗分为北方地区供暖能耗、除供暖外的住宅能耗、除供暖外的一般性非住宅民用建筑和大型公共建筑能耗四部分,着重分析了其中的除供暖外的住宅能耗。首先,阐述了我国住宅建筑能耗的现状,指出目前我国住宅建筑能耗水平较低,但呈现加速增长的趋势;其次,针对我国住宅建筑能耗的刚性增长趋势,提出了住宅建筑节能的重点——住宅空调器升级与更新、降低照明能耗和减少家电待机损失。并分析计算了三个方面的节能措施所能达到的实际节能效果。     

Comparison between measured and calculated energy performance for dwellings in a summer dominant environment

The objective of this study is to present a comparison between the measured and the calculated energy performance of dwellings. For this purpose, the energy consumption of ten dwellings is measured for one year. The added value of this work is that it is performed in a summer dominant environment. The energy needs of the same dwellings are also calculated by means of the methodology based on European Standards described in the CEN/TR 15615:2008 technical report. According to the findings of this study, a large gap exists between the calculated and the measured energy consumption of the examined dwellings. In order to evaluate the reasons for this deviation, a detailed analysis of the heating and cooling loads of the dwellings is performed. The intermittent heating of the building is found to be simulated accurately by the employed methodology, whereas the comparison between the calculated and the measured cooling loads reveals a large deviation of about 150%. Based on the findings of this study, a factor of 0.6 should be adopted in the case of cooling schedule, compared to the heating operation of the building.     

Assessment of Portuguese thermal building legislation in an energetic and environmental perspective

The aim of this study is to assess the consistency of Portuguese thermal building legislation in terms of energy and environmental performance.To illustrate this, a case study has been carried out for different scenarios of a dwelling home located in an extreme climate zone (I3, V1 north) in Portugal with a T3 typology: four occupants and net floor area of 150 m², modelled according to Regulation Thermal Performance Characteristics of Buildings and a Life Cycle Assessment approach.The results show that the Portuguese thermal building legislation can be considered consistent in terms of energy efficiency and environmental performance if we take the damage categories into account - “human health” or “ecosystem quality” or the impact category - “emission into air”. It cannot be considered consistent if we take the damage category into account - “resources” or the impact category - “CO₂ eq” (equivalent carbon dioxide emissions)/“climate change”/“global warming”.     

夏热冬冷地区办公建筑降低供暖空调能耗的技术路径

以上海地区某办公建筑为例,基于EnergyPlus能耗模拟,探讨了围护结构性能提升和暖通空调系统优化这2条节能技术路径对夏热冬冷地区办公建筑降低供暖空调全年能耗的有效性.结果 表明:围护结构性能提升的节能潜力较小,经济性较差;单纯提高围护结构保温隔热性能并不能保证降低建筑年耗冷量,应综合分析全年供热供冷能耗确定围护结构...     

我国广义建筑能耗状况的分析与思考

对广义建筑能耗的组成进行分析,并从运行能耗、建材能耗与间接能耗三方面对我国建筑能耗状况进行分析。结果表明,我国广义建筑能耗与全国总能耗呈现很强的线性相关性,广义建筑能耗与全国总能耗的比例约为45.5%。在广义建筑能耗中,运行能耗、建材能耗与间接能耗约占全国总能耗的20%、15%和10.5%,减少建筑运行能耗是建筑节能的关键,但减少建筑材料能耗具有同样重要的意义。     

Methodology to estimate building energy consumption using EnergyPlus Benchmark Models

The evaluation of building energy consumption usually requires building energy profiles on an hourly basis. Computer simulations can be used to obtain this information but generating simulations requires a significant amount of experience, time, and effort to enter detailed building parameters. This paper presents a simple methodology to estimate hourly electrical and fuel energy consumption of a building by applying a series of predetermined coefficients to the monthly energy consumption data from electrical and fuel utility bills. The advantage of having predetermined coefficients is that it relieves the user from the burden of performing a detailed dynamic simulation of the building. The coefficients provided to the user are obtained by running EnergyPlus Benchmark Models simulations; thus, the simulation process is transparent to the user. The methodology has been applied to a hypothetical building placed both in Atlanta, GA, and in Meridian, MS, and in both cases, errors obtained for the estimated hourly energy consumption are mainly within 10%.     

我国夏热冬暖地区和夏热冬冷地区建筑节能的差异性分析

本文阐述我国夏热冬暖地区和夏热冬冷地区的气候和居住建筑能耗特点,分析建筑围护结构外墙和外窗热工性能对建筑能耗和节能的不同影响,为建筑节能标准的规定值确定提供相应的依据。     

京津地区夏季着装行为对办公建筑空调能耗的影响

着装行为通过影响室内空气参数的设定而影响建筑空调能耗。利用能耗模拟软件DeST,计算出该地区典型着装行为下实测运行参数与期望参数对应的建筑空调能耗比推荐标准下能耗分别降低了10.86%和13.16%。而基于典型着装行为的实验热学性能参数下,平均只降低4%,说明由着装热阻关联的主观温度需要按地区着装行为进行修正。提出了控制建筑空调能耗的着装行为调节模型,着装行为节能率εc为负值时节能,为正值时不节能。京津地区办公建筑节能率为0的临界服装热阻为0.563clo,空调系统设计和运行节能的前提是,着装热阻低于临界值。着装行为调节模型为地区着装形式和着装面料提供了量化标准,为精确控制建筑能耗提供了一种方法。     

建筑师负责制下我国建筑师的职能、权利与义务

对中外建筑师制度进行对比,发现中外建筑师制度在职能、权利、义务等方面的差异,认识到我国现行注册建筑师制度的不足。探讨了推行建筑师负责制的必要性以及新时代应当赋予其怎样的责任与义务。最后以雄安新区旧改项目为例,阐述推行建筑师负责制的亟需性与我国建筑师的能力提高空间。     

Robustness of a methodology for estimating hourly energy consumption of buildings using monthly utility bills

The evaluation of building energy consumption under typical meteorological conditions requires building energy profiles on an hourly basis. Computer simulations can be used to obtain this information, but generating simulations requires a significant amount of experience, time, and effort to enter detailed building parameters. This paper considers a simple methodology for using existing EnergyPlus benchmark building energy profiles to estimate the energy profiles of buildings with similar characteristics to a given benchmark model. The method utilizes the building monthly energy bills to scale a given benchmark building energy profile to approximate the real building energy profile. In particular, this study examines the robustness of the methodology considered with respect to the parameter discrepancies between a given building and the corresponding EnergyPlus benchmark model used to estimate its profile. Test buildings are defined by perturbing several combinations of the parameters defined in the benchmark building model. The test buildings examined are similar to the EnergyPlus, medium sized office, benchmark building in Baltimore, MD, and a total of 72 distinct test building configurations are examined. The analysis reveals that the methodology can significantly reduce the errors introduced by discrepancies from the EnergyPlus benchmark model.     

Effects of Global Climate Change on Building Energy Consumption and Its Implications in Florida

ABSTRACT

Many studies have investigated the impact of global warming on energy consumption. In this study, the morphing method and EnergyPlus (E+) software were used to investigate the impact of climate change on commercial building energy use under the A2 medium-CO₂. emission scenario. The study simulated electricity and gas consumption of nine types of commercial buildings in eight cities, representing three climate zones in Florida. The nine types of commercial buildings included apartments, hotels, offices, and schools. The energy simulation results showed the future trends of growth and reduction in electricity and gas consumption for cooling and heating in TMY2 (TMY3), 2020, 2050, and 2080 in the eight selected cities. In general, gas and electricity demands for heating are projected to decrease, and electricity demand for cooling increases, at different rates in various areas of Florida. The study provides guidance for policy‐makers and utility companies as they craft their response to climate change in various regions of Florida.     

浅谈矿渣水泥的粉磨技术

本文介绍了矿渣水泥的不同粉磨工艺,包括熟料、石膏与矿渣的共同粉磨以及矿渣的单独粉磨,并指出矿渣 单独粉磨和预粉磨是今后的发展方向。     

建筑设计中的节能措施

该文的目的是要解决当前建筑高耗能的问题。研究过程和方法是细致分析规划设计、建筑设计和设备设计中所涉及的要素,提炼归纳出有利于节能的措施和方法。研究的结论是在实践工程设计中综合运用各节能措施,达到相应的节能目的。     

Application of energy rating methods to the existing building stock: Analysis of some residential buildings in Turin

The objective of this work is to contribute to the recent standardisation activity, finalized to apply the Energy Performance of Buildings Directive (EPBD). Through the energy assessment of some residential buildings in Turin (Italy), the work investigates the application of the calculation methods that have been specified in the recent European standard for the so-called “standard energy rating”. A comparison of the “calculated energy rating” with the “measured energy rating” is used to investigate the effect of user behaviour and weather conditions. Moreover, in order to draft the energy certificate and make an appropriate classification, the last part of the work investigates the way to find energy reference values of the building stock, through the study of the correlation between the input and the output data of an energy rating and the comparison of the analysed buildings.     

Improving energy efficiency through the design of the building envelope

Buildings, their surroundings and related enterprises produce more CO₂, generate more pollution, consume more energy, and waste more natural resources than any other human enterprise or industry. Moreover, considerable parts of these environmental impacts are the results of the lodging industry [1].     

夏热冬暖地区中庭的天窗型式与耗能

通过建立中庭天窗模型,分析、探讨了不同型式、不同倾角、不同朝向的天窗与耗能的关系。     

A systematic procedure to study the influence of occupant behavior on building energy consumption

Efforts have been devoted to the identification of the impacts of occupant behavior on building energy consumption. Various factors influence building energy consumption at the same time, leading to the lack of precision when identifying the individual effects of occupant behavior. This paper reports the development of a new methodology for examining the influences of occupant behavior on building energy consumption; the method is based on a basic data mining technique (cluster analysis). To deal with data inconsistencies, min-max normalization is performed as a data preprocessing step before clustering. Grey relational grades, a measure of relevancy between two factors, are used as weighted coefficients of different attributes in cluster analysis. To demonstrate the applicability of the proposed method, the method was applied to a set of residential buildings’ measurement data. The results show that the method facilitates the evaluation of building energy-saving potential by improving the behavior of building occupants, and provides multifaceted insights into building energy end-use patterns associated with the occupant behavior. The results obtained could help prioritize efforts at modification of occupant behavior in order to reduce building energy consumption, and help improve modeling of occupant behavior in numerical simulation.