Improved benchmarking comparability for energy consumption in schools

The method behind the UK Display Energy Certificate (DEC) improves the comparability of benchmarking by accounting for variations in weather and occupancy. To improve the comparability further, the incorporation of other features that are intrinsic to buildings (e.g. built form and building services) deserve exploration. This study investigates the impact of these features and explores ways to improve further comparability in benchmarking the energy performance of schools. Statistical analyses of approximately 7700 schools were performed, followed by analyses of causal factors in 465 schools in greater detail using artificial neural networks (ANNs), each designed to understand and identify the factors that have significant impact on the pattern of energy use of schools. Changes in the pattern of energy use of schools have occurred over the past four years. This fact highlights issues associated with static benchmarks. A significant difference in energy performance between primary and secondary schools meant that it was necessary to re-examine the way non-domestic buildings are classified. Factors were identified as having significant impact on the pattern of energy use. The characteristics raise new possibilities for developing sector-specific methods and improving comparability.     

Energetische Sanierung von Schulgebäuden in den neuen Bundesländern – Sanierungsprojekt Förderschule Rathenow

Energy efficiency improvements for school buildings in Germany's new federal states; Rathenow special school refurbishment project. Current energy saving measures for existing buildings focus on refurbishment of schools and other educational buildings. The building described in this article represents the standard type of a large‐panel construction series in the new federal states. Due to the large number of buildings (540) constructed in this way the project can act as a model for similar projects. Initial studies indicated that structural refurbishment measures for these buildings are required as a matter or urgency. The energy performance calculations for the building showed good agreement between the calculated demand values and actual heating energy consumption values and can serve as basis for predictions of energy savings through various refurbishment measures. The new DIN 18599 calculation standard enables significantly more differentiated consideration of boundary conditions such as occupied periods, occupancy levels, internal heat sources, and the effect of night setback. Based on comparative calculations, different refurbishment concepts can be developed and assessed.     

Behavioral variables and occupancy patterns in the design and modeling of Nearly Zero Energy Buildings

The objective of obtaining high performance energy buildings can be reached considering the contemporaneous effects of technical characteristics and occupancy. Recent studies report that as buildings become more energy efficient, the behavior of occupants plays an increasing role in consumption. Therefore, a construction designed to be a Nearly Zero Energy Building (nZEB) might generate higher consumption than expected if the assumptions made in the simulation process are not respected during the real use. The occupant can modify the control strategies of internal variables (heating/cooling system operation, set point temperature, ventilation, lighting) and the users’ behavior has a high impact on the utilization of plants and equipment. A significant contribution is also represented by the internal gains that have a direct relation with occupancy. The aim of this study is to assess the influence of housing occupancy patterns on the definition of residential nZEB in Italian climatic conditions. The investigation has been carried out considering a case study consisting of a building designed according to the National Standards. Successively, different conditions of the building usage are analyzed using dynamic energy simulations that allow exploration of the different occupation modes. The variability of the family composition and the occupancy scenarios are defined based on the data collected in the specific context. The investigation provides information regarding the effects of human variables (occupants’ needs and preferences) on the final energy performance of low energy buildings and highlights the combination of variables that are important in the definition of nZEB as net zero source energy.     

基于清洁生产理念的建筑节能

我国建筑节能状况落后,用能不合理,亟待改善.把"清洁生产"理念引入建筑节能中,从当前建筑节能存在的问题及重点出发,指出了建筑节能设计处于节能工程的首位,是最关键的环节.明确了节能设计通过施工得以实现,施工质量影响着建筑节能,运行管理是达到建筑节能效果的重要环节.应特"清洁生产"理念始终贯彻于建筑节能设计、施工及运行管理全过程中,以期对建筑节能工作的发展有所启迪.     

Energy budgets for new construction

In support of a performance (energy budget) energy conservation standard, this paper explores by means of computer simulation, the variation of energy consumption in schools, with such factors as occupancy, size and location. Computed results are compared with recorded consumptions. A method of calculating and specifying energy budgets is presented. The use of energy budgets for energy conservation standards is discussed.The work described, though relating specifically to schools, has general relevance to other building types.     

Building energy simulation and optimization: A case study of industrial halls with varying process loads and occupancy patterns

Industrial halls are mainly low-rise rectangular-shaped structures of simple construction. The relatively loose requirements in space conditioning and the comparatively high internal heat gain make the approach in industrial hall design quite different from that of office building design. The simplicity in building geometry and construction method allows the investigation of energy consumption for building services to be limited to a few demand-side parameters, namely, resistance of the roof and wall insulation, airtightness, and amount of daylighting. This paper investigates the impact of varying these demand-side parameters on the energy consumption for space conditioning and lighting for a typical industrial hall. Through building energy simulation, such impacts can be investigated, and by applying optimization, the configurations of the most optimal combinations of demand-side parameters with the lowest energy consumption can be identified. The result suggests that there is a significant energy-saving potential. For industrial halls, energy consumption for building services can be very sensitive to changes in the process load and occupancy pattern, which in reality, fluctuate widely due to economic cycles, and other factors. Optimized design solutions for industrial halls intended for a particular process load and occupancy pattern might not perform as predicted due to potential changes. To account for potential changes, uncertainty analysis can be performed to determine if the optimized design solutions are in fact robust enough to such changes and to identify solutions that are less susceptible to uncertainty.     

Energy and demand implication of using recommended practice occupancy diversity factors compared to real occupancy data in whole building energy simulation

Whole building energy simulation tools have become increasingly useful in assessing and improving existing and designing new high-performance buildings. Occupancy diversity factors are one category of parameters needing additional consideration in energy modelling as they can have a large impact on the output of the simulation. In this study, two sources of occupancy diversity factors, American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) references and measured data from Duarte, Van Den Wymelenberg, and Rieger. [2013a. “Revealing Occupancy Patterns in an Office Building Through the Use of Occupancy Sensor Data.” Energy and Buildings 67 (December): 587–595. doi:10.1016/j.enbuild.2013.08.062], are used in three Department of Energy (DOE) reference office building models and four calibrated models of existing buildings. The total energy consumption between the two schedules for an assumed private office dominate floor plan layout ranges between 21.5–39.1% and 0.8–5.8% for an open office dominate plan in reference buildings. Calibrated models range from 5.5% to 16.8%. These results are meant to represent a reasonable range of potential impacts of occupancy diversity factors, and are thus derived by applying occupancy profiles directly to occupancy, lighting, plug load, and ventilation schedules.     

北京住宅舒适度与低能耗研究

本文详尽阐述了在中国建筑产业中强劲的能源需求与能源浪费之间的矛盾,并以北京住宅为例,探讨了以合理的投入获得住宅舒适度的可能和方法。快速的经济增长促使人们对住宅的舒适度要求越来越高;但由于建筑的维护结构不能很好地适应自然,供热系统也相对粗放,达到最基本的室内环境标准往往要付出很高的代价。本文详尽地研究了建筑的维护结构、自然及建筑能耗的关系:运用国际流行的热舒适度评估软件TAS建立了深入研究建筑维护结构的模型,以维护结构中每个细小参数的变化对整体建筑能耗和舒适度影响的分项评估为基本研究方法,研究结果表明建筑维护结构的任何一个单项元素对整体能耗的影响都是有敏感区的;同时也表明任何评价都要以整体的节能水平和经济回报率为基础去衡量才有意义。     

What next for energy-related building regulations?: the occupancy phase

Building regulations are important policy instruments for increasing building energy efficiency. However, when it comes to actual energy use, studies have shown that improvements in building energy efficiency are offset by changes in the inhabitants’ comfort practices. Nevertheless, the improvement of energy efficiency continues to be a cornerstone in building regulations, with no consideration of how this simultaneously influences everyday practices. The example of Danish building regulations, which are among the strictest in Europe, is critically reviewed for the implications regulatory design can have for reducing energy consumption. Based on readings of policy documents, consultancy reports and research papers from the last two decades, this paper outlines where things go amiss during a building’s lifetime if a user perspective is excluded. The focus is on three phases: the development of new building technologies, the design and construction of buildings, and occupancy. The question of how building regulations could be redesigned to regulate energy use better is explored, along with what research and strategies are needed within four domains: developing alternative measures to energy per square meter; developing more advanced models simulating occupancy; improving feedback technologies’ usability; and the increased use of commissioning and post-occupancy evaluations.     

A user-centric space heating energy management framework for multi-family residential facilities based on occupant pattern prediction modeling

Space heating is the highest energy consumer in the operation of residential facilities in cold regions. Energy saving measures for efficient space heating operation are thus of paramount importance in efforts to reduce energy consumption in buildings. For effective functioning of space heating systems, efficient facility management coupled with relevant occupant behaviour information is necessary. However, current practice in space heating control is event-driven rather than user-centric, and in most cases relevant occupant information is not incorporated into space heating energy management strategies. This causes system inefficiency during the occupancy phase. For multi-family residential facilities, integrating occupant information within space heating energy management strategies poses several challenges; unlike with commercial facilities, in multi-family facilities occupant behavior does not follow any fixed activity-schedule pattern. In this study, a framework is developed for extracting relevant information about the uncertainties pertaining to occupant patterns (i.e., demand load) in multi-family residential facilities by identifying the factors affecting space heating energy consumption. This is achieved using sensor-based data monitoring during the occupancy phase. Based on the analysis of the monitoring data, a structure is defined for developing an occupant pattern prediction model that can be integrated with energy management strategies to reduce energy usage in multi-family residential facilities. To demonstrate the developed framework, a multi-family residential building in Fort McMurray, Canada, is chosen as a case study. This paper shows that integrating the developed occupant pattern prediction model within space heating energy management strategies can assist facility managers to achieve space heating energy savings in multi-family residential facilities.     

德国新型建筑节能理念与应用

介绍了德国当前的建筑节能理念和实际技术的应用,并针对中国目前情况提出建筑生态节能设计系统的概念及其重要组成部分;建筑整体的能量平衡系统设计;优秀的建筑构造系统设计和正确地选用建筑材料和技术设备系统。     

Integrating physical and virtual environments to conserve energy in buildings

Fundamental understandings of how energy is consumed, monitored, and controlled are key prerequisites for an energy conservation process. Users who know exactly when energy consumption occurs and where it takes place are able to make more informed decisions about how to lower their energy consumption. Energy conservation projects in the U.S. have reported a 2-11% savings when users are presented with information on energy consumption. Engineers are increasingly turning to virtual environments to improve system design and development and optimize performance and increase efficiency during operation. A bottom-up approach to real-time energy monitoring by integrating virtual and physical domains to increase user awareness on where, when, how and why aspect of energy to make inform decisions regarding energy consumption, optimization and conservation is proposed. A virtual 3-D environment is developed to display actual space/zone/building real-time power consumption information and to allow users to easily locate equipment/loads that are in standby/inefficient and causing energy waste in the real/physical environment. The proposed system is demonstrated via a prototype board that is virtually integrated with an actual Zero Net Energy Test House (ZNETH) as part of future Net-Zero Energy buildings research. The results establish a promising tool in this filed.     

Model-based real-time whole building energy performance monitoring and diagnostics

Building energy systems often consume approximately 16% more energy [Mills, E. 2011. “Building Commissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse Gas Emissions in the United States.” Energy Efficiency 4 (2): 145–173] than is necessary due to system deviation from the design intent. Identifying the root causes of energy waste in buildings can be challenging largely because energy flows are generally invisible. To help address this challenge, we present a model-based, real-time whole building energy diagnostics and performance monitoring system. The proposed system continuously acquires performance measurements of heating, ventilation and air-conditioning, lighting and plug equipment usage and compare these measurements in real-time to a reference EnergyPlus model that either represents the design intent for the building or has been calibrated to represent acceptable performance. A proof-of-concept demonstration in a real building is also presented.     

议居住建筑节能设计标准的差异对节能设计的影响

节能减排是当今社会的重大议题,自2008年10月1日实施《民用建筑节能条例》以来,居住建筑节能设计取得了显著效果,大大降低了居住建筑的能耗,节约了大量能源。但在实际执行过程中,却存在对节能设计概念模糊、节能计算方法有误以及节能设计审查不严等问题。致使出现一些虽形式上满足节能设计要求,但却存在严重能耗问题的伪节能居住建筑。这些问题的存在原因很多,其中各地方节能设计标准本身对节能设计的定义描述、具体要求及评价标准的差异是重要原因之一。论文仅就此方面举例探讨其对节能设计结果的影响,以期对节能设计者提供帮助,给规范修订者提供参考。     

节能住宅设计的耗能量计算

住宅建筑能源消耗量与外围护结构的厚度、材料热阻有着密切相关,对今后的新建住宅建筑在设计中必须达到国家规定的标准值。通过一栋既有建筑的住宅楼采用了节能住宅的能源消耗量计算,对不同的参数进行了分析,从中判定是否是节能住宅建筑。     

The Energy Concept Adviser—A tool to improve energy efficiency in educational buildings

Educational buildings such as kindergartens, schools and universities display many similar design, operation and maintenance features in most countries. The two most noteworthy similarities amongst these building types are the high energy consumption and the necessity for retrofitting many buildings within this sector. However, studies have shown that during retrofit, energy saving measures are only rarely applied, because the decision-makers lack knowledge of investments and the efficiency of potential energy saving measures. The main goal of the International Energy Agency ECBCS Annex 36 is to provide the educational building decision-makers with sufficient data, information and tools to improve their learning and teaching environments by improving the energy efficiency of their buildings.     

Understanding occupancy pattern and improving building energy efficiency through Wi-Fi based indoor positioning

Detailed visualisation and data analysis of occupancy patterns including spatial distribution and temporal variations are of great importance to delivering energy efficient and productive buildings. An experimental study comprising 24-h monitoring over 30 full days was conducted in a university library building.Occupancy profiles have been monitored and analysis has been carried out. Central to this monitoring study is the Wi-Fi based indoor positioning system based on the measured Wi-Fi devices' number and locations and data mining methods. Distinct from traditional occupancy and energy studies,more detailed informationrelated to the indoor positions and number of occupants has offered a better understanding of building user behaviour. The implication of the occupancy patterns for energy( e. g. lighting and other building services) efficiency is assessed,assisted with data from lighting sensors where needed. It is found occupancy patterns change dramatically with time. Also,the energy waste patterns have been identified through the method of data association rule mining. If the identified energy waste is removed,the total energy consumption can be reduced by 26. 1%. The indoor positioning information also has implications for optimizing space use,opening hours as well as staff deployment. The work could be extended to more rooms with diverse functions,other seasons and other types of non-domestic buildings for a more comprehensive understanding of building user behaviour and energy efficiency.     

节约型校园节能监管平台的建设与应用

高校是能耗较高的公共机构之一,节约型校园的建设工作越来越受到广泛关注。从能源管理、能源计量、能耗统计、部门用能区分等角度分析了建设高校节约型校园监管平台的必要性和重要性,以东北某高校节约型校园节能监管平台的建设为案例,研究了高校节能监管平台的设计、建设、系统构成及使用功能,总结探讨了节能监管平台的应用管理方法。节能监管平台的建设实施为规范校园节能管理手段、提高能源管理效率提供了帮助,为节约型校园的建设提供了依据。     

建筑节能改造的外部性分析与激励政策

建筑节能是保障国家能源安全、保护环境、提高人民生活质量、建设节约型社会的重大举措.本文通过深入探讨建筑节能的外部性原理及其福利改进的影响,提出了相关的经济激励政策与设计思路,为推动我国建筑节能工作的开展提供建议.     

Energy conservation and retrofitting potential in Hellenic hotels

Energy consumption data from 158 Hellenic hotels and estimated energy savings that result from the use of practical retrofitting techniques, materials and new energy efficient systems are presented. The data were collected during an extensive energy audit of buildings that was carried out in Hellas, within the frame of a National Energy Programme sponsored by the CEC VALOREN Programme, for energy conservation in buildings. During this short monitoring campaign and on-site visits of a trained panel of engineers to each building, all information related to the building's construction, heating, cooling and lighting systems, and all other mechanical and electrical systems, was collected. The main results and energy characteristics of cooling, heating and lighting on energy consumption and performance are discussed. The annual average total energy consumption in hotels is 273 kWh/m², one of the highest among all categories of buildings. Several scenarios for possible interventions to the building's outer envelope, heating, cooling and lighting systems are proposed and evaluated, in order to assess the effectiveness of various energy conservation techniques. Based on the results from several simulations, it is concluded that it is possible to reach an overall 20% energy conservation.