Implementing effect of energy efficiency supervision system for government office buildings and large-scale public buildings in China

The Chinese central government released a document to initiate a task of energy efficiency supervision system construction for government office buildings and large-scale public buildings in 2007, which marks the overall start of existing buildings energy efficiency management in China with the government office buildings and large-scale public buildings as a breakthrough. This paper focused on the implementing effect in the demonstration region all over China for less than one year, firstly introduced the target and path of energy efficiency supervision system, then described the achievements and problems during the implementing process in the first demonstration provinces and cities. A certain data from the energy efficiency public notice in some typical demonstration provinces and cities were analyzed statistically. It can be concluded that different functional buildings have different energy consumption and the average energy consumption of large-scale public buildings is too high in China compared with the common public buildings and residential buildings. The obstacles need to be overcome afterward were summarized and the prospects for the future work were also put forward in the end.     

架空构架式太阳热水器系统

分析了当前太阳热水器和住宅建筑结合的现状,指出太阳热水器在住宅建筑上应用的限制因素;针对所存在的问题,提出了太阳热水器与住宅建筑结合的一种方式--"架空构架式".它和建筑一体化结合,构造、施工简单,对屋面使用没有影响,经济性好.因此必将成为今后高层住宅建筑太阳能一体化的发展趋势.     

Energy sovereignty in Italian inner areas: Off-grid renewable solutions for isolated systems and rural buildings

This paper deals with a compact system developed to assure energy independence to buildings located in inner rural areas: the Off-Grid Box. This system features a combination of techniques that assure the use of several renewable energy sources, their storage and the rationalization of consumption.This research studies the base model of the Off-Grid Box, which entails the presence of photovoltaic panels as the energy capture system.The aim of this research is to evaluate the opportunity of realizing a system to ensure energy autonomy of rural residential buildings. To achieve energy independence, for an isolated dwelling, this paper assesses the optimal storage systems that may be combined with a photovoltaic system. To this end, an Off-Grid Box has been installed in a residential unit in central Italy. Starting from the real case, two alternative energy storage scenarios were constructed. The results can be applied to a variety of geographical settings and prove the feasibility and strategic importance of total off-grid systems for individual residential units, when they are designed in integrated terms in the area to implement small-scale-smart-grids. In rural areas, these grids should also cater for small farming businesses that feature a different consumption distribution compared to dwellings.     

Analysis of embodied energy use in the residential building of Hong Kong

Energy use in buildings accounts for nearly half of the total primary energy use in Hong Kong. Until now, studies have primarily focused on energy conservation in building operation, even though recent research has indicated that the embodied energy used in residential buildings could account for up to 40% of the life-cycle energy used in residential buildings. Accordingly, this paper presents a study on the energy embodied in the residential building envelope of Hong Kong. A model for estimating the intensities of the embodied and demolition energy for buildings has been developed. Two typical high-rise residential buildings, the Housing Authority Harmony 1 and the New Cruciform blocks, are analysed based on the developed model. The results of the analysis provide an insight into the embodied energy usage profile in residential buildings in Hong Kong. Energy embodied in steel and aluminium ranks as the first and second largest energy demand and may account for more than three-quarters of the total embodied energy use in a residential building envelope in Hong Kong. This reveals those building components with significant potential for reduction in embodied energy demand.     

Residential hot water use patterns in Greece

This paper presents the results from the monitoring of hot water consumption in four apartment buildings that are located in Solar Village 3, in Greece. The buildings were monitored centrally for hot water consumption using a Data Acquisition System (DAS). The hot water is prepared in one building by an air-to-water heat pump and in the other three buildings by central solar plants. The main objective of the paper is the development of average residential hot water use patterns based on data from actual measurements conducted over the period September 1990 to August 1991. Average hourly, daily, and yearly profiles, which refer to central DHW systems, are presented and discussed. The average hot water consumption “per person” is also concluded. In addition, the effect of “family size” in hot water use is examined. It was found that the majority of the families consume between 25 and 35 liters per person per day, and the mean annual energy consumption is 0.83 kWh per person per day.     

Path Analysis of Energy-Saving Technology in Yangtze River Basin Based on Multi-Objective and Multi-Parameter Optimisation

The Yangtze River Basin in China is characterised by hot-and cold-humid climates in summer and winter, respectively. Thus, increased demand for heating and cooling energy according to the season, as well as poor indoor thermal comfort, are inevitable. To overcome this problem, this study focused on the influence of passive design and heating, ventilation, and air conditioning equipment performance on the energy performance of residential buildings, and explored potential energy-saving technology paths involving passive design and improved coefficient of performance through a multi-objective and multi-parameter optimisation technique. A large-scale questionnaire survey covering a typical city was first conducted to identify family lifestyle patterns regarding time spent at home, family type, air conditioner use habits, indoor thermal comfort, etc. Then, the actual heating and cooling energy consumption and information of model building were determined for this region. Subsequently, the design parameters of an individual building were simulated using Energyplus to investigate the cooling and heating energy consumption for a typical residential building with an air conditioner. The results indicated an improvement of approximately 30% in energy efficiency through optimisation of the external-wall insulation thickness and the external-window and shading performance, and through use of appropriate ventilation technology. Thus, a multi-objective and multi-parameter optimisation model was developed to achieve comprehensive optimisation of several design parameters. Experimental results showed that comprehensive optimisation could not only reduce cooling and heating energy consumption, but also improve the thermal comfort level achieved with a non-artificial cooling and heating source. Finally, three energy-saving technology paths were formulated to achieve a balance between indoor thermal comfort improvement and the target energy efficiency(20 kWh/(m2?a)). The findings of this study have implications for the future design of buildings in the Yangtze River Basin, and for modification of existing buildings for improved energy efficiency.     

Scenarios of application of energy certification procedure for residential buildings in Lebanon

This paper describes the results of a French–Lebanese scientific cooperation, between 2001 and 2005, about “Rational use of energy in the residential buildings in Lebanon and adaptation of an energy certification procedure”. The aim of this project is to promote the energy efficiency in the existing residential buildings in Lebanon, using an energy certification procedure, and to evaluate the energy certification foresight with prospective methods.     

BIPV/T技术在新徽派民居中的应用探索

针对新徽派民居中存在的建筑能耗大、热舒适性差及室内空气品质低等问题,探索在保持建筑典型特点的前提下,将太阳能光伏光热建筑一体化(BIPV/T)新技术和新方法在新徽派民居中综合运用.文章主要基于作者团队最新的研究,探讨了兼顾"黛瓦"的光伏瓦技术、兼顾"粉壁"的集热?除甲醛多效墙体技术、兼顾"马头墙"的通风?除菌杀毒多效太...     

Potential of energy and water efficiency improvement in Abu Dhabi's building sector – Analysis of Estidama pearl rating system

Energy and water infrastructure in Abu Dhabi provides a strong example of the interconnection between energy and water, where the majority of its electricity and water demand is jointly produced from cogeneration plants. The total cost of fuel used for cogeneration plants are heavily depending on the efficiency level of end-use energy and water consumption. Buildings are the major electricity and water consumers with 84.6% and 92.2% respectively from the entire demand. The aim of this study is to analyze the energy and water consumption reduction by implementing Estidama pearl regulations and compare it with Business as Usual -the normal execution of things as they always do-for three sample buildings (villa, multistory residential and office building). For energy assessment, eQUEST software was used to examine the energy performance of the chosen buildings and to evaluate the energy saving potential after applying Estidama requirements. While for water assessment; Estidama and LEED calculation tools were used to do the same. The results of energy simulation and water analysis of the chosen buildings showed a potential of electricity reduction between 31% and 38% and a potential of water reduction between 22% and 36% depending on building type and other parameters. Also, a total monetary savings of 19 Billion AED can be achieved cumulatively over ten years period (2011–2020) after Estidama regulations have been applied. In addition, a reduction of 31.4 Million ton of CO₂eq cumulatively can be achieved.     

建筑形式对太阳能热利用的影响研究

以上海地区的住宅建筑为研究对象,通过模拟分析的方法,采用DeST软件计算确定建筑逐时的采暖、空调能耗,研究分析窗墙比对建筑全年采暖能耗、全年空调能耗以及全年采暖、空调总能耗的影响规律,研究分析太阳辐射热增加所导致采暖能耗的降低幅度与外围护结构保温性能两者之间的定量关系。计算结果表示在夏季外窗遮阳和夜间通风的条件下,加大南向窗墙比可增强太阳能的热利用效率,降低建筑全年的采暖、空调总能耗;而外围护结构保温性能的增强则可降低室内向室外散热的程度,相应提高对冬季太阳辐射的热利用程度,从而达到降低采暖能耗的目的。     

Energy performance of residential buildings in Singapore

Energy consumption of buildings takes up about a third of Singapore's total electricity production. In this paper, we present a pioneering study to investigate the energy performance of residential buildings. Beginning with an energy survey of households, we established the air-conditioning usage patterns and modelled residential buildings for computer simulations. An ETTV equation for residential buildings was developed. Employing this equation, we demonstrated how to achieve improved energy efficiency in residential buildings. Two types of residential buildings, namely, point block and slab block, were modelled and parametric runs performed. ETTV impacts the energy consumption of residential buildings and thus lowering the ETTV will result in reduced building heat load. Results from the developed equation showed that a unit decrease in ETTV resulted in 4% and 3.5% reduction in annual cooling energy for point block and slab block residential buildings, respectively. In addition, a set of simple energy and load estimating equations were developed using computer simulation and local climatic data. These equations provided a means of estimating the annual cooling energy consumption of residential buildings in Singapore.     

采暖居住建筑节能改造收益分析

面对我国华北地区既有采暖居住建筑节能改造资金的匮乏 ,提出既有建筑的节能改造经济性分析不仅要计算冬季供暖节能收益 ,而且还要包括夏季空调节能收益 ,同时还应计入冷热源建设等潜在经济收益 ,这对缩短既有建筑节能改造初投资回收期、推动我国建筑节能的发展具有积极意义。     

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.     

An experimental study on clothes drying using rejected heat (CDURH) with split-type residential air conditioners

This paper reports on an experimental study on the effectiveness of using heat rejected from a split-type residential air conditioner (RAC) for clothes drying in residential buildings. An experimental rig has been set up and extensive experimental work has been carried out. The effectiveness was evaluated based on the comparisons by various drying methods, in terms of drying duration required, energy consumption, under Hong Kong's climatic conditions. Results from the study indicated that CDURH in residential buildings can be effective for its reasonably short drying duration and high energy use efficiency during air conditioning seasons. The additional electricity use for restoring condenser air flow rate with CDURH so as not to affect the operating efficiency of a RAC was only about 1.2% of that used by an electrical tumbler dryer to complete the same clothes-drying job. In order to have a large-scale application of CDURH in residential buildings in highly-dense urban areas, it is suggested that current design practices of residential air conditioning be reviewed and CDURH be integrated in the design stage of a residential development.     

Applications of Thermal Energy Storage in Saudi Arabia

In Saudi Arabia, the heating, ventilating and air conditioning (HVAC) system typically accounts for 65% of the total electrical energy consumption in buildings. This is due to a very high ambient temperature which persists for a long period of time in a summer season. Moreover, gas turbines efficiency decrease also with the high ambient temperatures. In the HVAC industry cool storage, or commonly known as Thermal Energy Storage (TES) is the most preferred demand side management (DSM) technology for shifting cooling electrical demand from peak daytime periods to off‐peak night‐time. The most popular and well‐suited TES concept for Saudi Arabia is either chilled water or ice storage system, depending upon the applications and the required storage capacity. This paper shows how TES offers a means of reducing the electrical demand in large commercial buildings. Additionally, it is seen that efficiencies of the air cooled chillers are increased if they run overnight. Similarly efficiencies of gas turbine is also increased when a TES based pre‐cooled air is used as an inlet to the turbine. This paper also discusses favouring conditions and other aspects of cool storage applications in Saudi Arabia. TES economics are considered and a cost analysis is presented to illustrate the potential savings that can be achieved by the use of TES in Saudi Arabia. Copyright © 1999 John Wiley & Sons, Ltd.     

A state-of-the-art review of the sustainability and energy efficiency of buildings in Saudi Arabia

Sustainable buildings have an important role in achieving sustainable development by improving energy utilization and environmental performance. Buildings are considered as the biggest single contributor to world energy consumption and greenhouse gas emissions. In Saudi Arabia, the significance of the building sector can be described on the basis of per capita electricity consumption, per capita carbon dioxide emissions, and the increasing number of buildings because of economic and population growth. Therefore, the country should consider establishing energy-efficient buildings to promote sustainable development. Efforts in developing energy-efficient technologies should increase for the national energy policy. This article comprehensively describes the current challenges and opportunities of energy consumption and various energy conservation options that are viable for the Saudi building sector. Current policy efforts for improving energy efficiency in Saudi buildings have been analyzed to enhance the sustainable development in the country. The study reveals that the energy conservation policy of the country has fairly improved in the past decades. However, the country has to focus on this area and perform urgent measures to adopt energy-efficient technologies in the building sector.     

寒冷(B)地区农村住宅能耗调研及分析

通过对寒冷(B)地区农村住宅的调查,获得了大量统计数据,并依据《严寒和寒冷地区居住建筑节能设计标准》(JG J26-2010)对数据进行了分析及总结。结果表明:寒冷(B)地区农村住宅存在一些弊端,如体型系数较大、能耗大、室内热舒适性差等,并分析了产生弊端的原因,为农村住宅的设计提供了参考依据。     

Applying water cooled air conditioners in residential buildings in Hong Kong

The objective of this study is to conduct a realistic prediction of the potential energy saving for using water cooled air conditioners in residential buildings in Hong Kong. A split type air conditioner with air cooled (AAC) and water cooled (WAC) options was set up for experimental study at different indoor and outdoor conditions. The cooling output, power consumption and coefficient of performance (COP) of the two options were measured and calculated for comparison. The experimental results showed that the COP of the WAC is, on average, 17.4% higher than that of the AAC. The results were used to validate the mathematical models formulated for predicting the performance of WACs and AACs at different operating conditions and load characteristics. While the development of the mathematical models for WACs was reported in an earlier paper, this paper focuses on the experimental works for the AAC. The mathematical models were further used to predict the potential energy saving for application of WACs in residential buildings in Hong Kong. The predictions were based on actual building developments and realistic operating characteristics. The overall energy savings were estimated to be around 8.7% of the total electricity consumption for residential buildings in Hong Kong. Wider use of WACs in subtropical cities is, therefore, recommended.     

Automated prediction system of household energy consumption in cities using web crawler and optimized artificial intelligence

The supply of electrical energy is critical to convenient and comfortable living. However, people consume a large amount of energy, contributing to an energy crisis and global warming, and damaging some ecological cycles. Residential electricity consumption has greater elasticity than industrial and business consumption; it therefore has high energy-saving potential. This work establishes an automated platform, which provides information about residential electricity consumption in each city in Taiwan. Machine learning was used to forecast future residential electricity demand. A nature-inspired optimization method was applied to enhance the accuracy of the best machine learner, yielding an even better hybrid ensemble model. Performance measures indicate that the resulting model is accurate and provides effective information for reference. An automatic web-based system based on the model was combined with a web crawler and scheduled to run automatically to provide information on monthly residential electricity consumption in each county and city. By providing energy consumption information across the country, power providers and government can discuss policy and set different goals for energy use. The results of this study can facilitate the early implementation of energy-saving and carbon emission-reducing in cities and aid utility companies in establishing energy conservation guidelines.     

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。