Analysis and forecast of residential building energy consumption in Chongqing on carbon emissions

Carbon emissions mainly result from energy consumption. Carbon emissions inevitably will increase to some extent with economic expansion and rising energy consumption. We introduce a gray theory of quantitative analysis of the energy consumption of residential buildings in Chongqing,China,on the impact of carbon emission factors. Three impacts are analyzed,namely per capita residential housing area,domestic water consumption and the rate of air conditioner ownership per 100 urban households. The gray prediction model established using the Chongqing carbon emission-residential building energy consumption forecast model is sufficiently accurate to achieve a measure of feasibility and applicability.

Simulation Technology of Environmental Impacts by Zero-energy Residential Buildings Based on Emergy Analysis Method

This paper presents a simulation technology of environmental impact for the building. By emergy analysis method,emergy costs of building( or construction engineering) can be calculated in the life cycle. It includes the engineering cost, environmental cost and social cost of building. Through integrating GIS technology with multi-agent technology,life cycle substance and energy metabolism of building( construction engineering) can be simulated and their environmental influence can be dynamically displayed. Based on the case study of entries works‘Sunny Inside'by Xiamen University in 2013 China International Solar Decathlon Competition,we discovered the changing pattern of surrounding environmental impact from waste streams of the zero-energy building and ordinary construction. The simulation results verified and showed the Odum principles of maximum power. This paper provides a new research perspective and integration approach for the environmental impact assessment in building and construction engineering. The result will help decision-making in design and construction engineering scheme.

Analysis of Renewable Energy Utilization Potential in Buildings of China

As a country of great population, China has increasing building energy consumption continuously. It not only threatens the lack of total energy but also hardens the progress of protecting environment. Therefore, it forces the country to accelerate finding substitution application of conventional energy in building, renewable energy building utilization. In base of 2010, this study explores the potential of the renewable energy building utilization by using energy consumption analysis until 2030 and predicts annual alternative quantity of renewable energy in different situations.

The Identification of Peak Period Impacts When a TMY Weather File Is Used in Building Energy Use Simulation

When typical meteorological year (TMY) data are used as an input to simulate the energy used in a building, it is not clear which hours in the weather data file might correspond to an electric or natural gas utility’s peak demand. Yet, the determination of peak demand impacts is important in utility resource planning exercises and in determining the value of demand-side management (DSM) actions. We propose a formal probability-based method to estimate the summer and winter peak demand reduction from an energy efficiency measure when TMY data and model simulations are used to estimate peak impacts. In the estimation of winter peak demand impacts from some example energy efficiency measures in Texas, our proposed method performs far better than two alternatives. In the estimation of summer peak demand impacts, our proposed method provides very reasonable results which are very similar to those obtained from the Heat Wave approach adopted in California.

Plus Energy Buildings:A Numerical Case Study

The feasibility of Plus Energy Building for a sample relevant case is investigated.After a literature review aimed to identify key aspects of this type of buildings,a preliminary evaluation of the thermal performance of a building constructed using conventional material is presented together with a parametric analysis of the impact of typical influential parameters.Solar domestic hot water(SDHW)and photovoltaic systems(PV)are considered in the study.Numerical simulations indicate that for the examined sample case(Beirut in Lebanon)the total annual energy need of conventional building is 87.1 kWh/y.m^(2).About 49%of energy savings can be achieved by improving the building envelope and installing energy efficient technologies.Moreover,about 90%of energy savings in domestic hot water production can be achieved by installing a SDHW system composed of two solar collectors connected in series.Finally,the addition of a grid connected PV array system can significantly mitigate the energy needs of the building leading to an annual excess of energy.

基于EnergyPlus的被动式建筑能耗仿真实验

该文将Energy Plus建筑能耗仿真与实际被动式建筑现场调研、能耗监测相结合,以青岛地区某被动房为案例,开展了包括现场调研、仿真结果验证、节能潜力分析和敏感性分析等内容的实验项目。实验结果表明,该实验方法可操作性强,仿真结果与实测数据吻合度高,被动式建筑的节能效果得到有效验证。案例被动式建筑全供暖及供冷能耗指标分别为14.08 k Wh/m^(2)·a和8.37 k Wh/m^(2)·a,相比传统建筑全年节能55.26%,其中空调节能率高达56.95%;外墙、外窗保温、遮阳系统等被动措施是主要节能来源,节能占比分别为26.54%、23.58%和23.97%;灰色关联分析显示,外墙传热系数对全年能耗的敏感度最高。

An active pipe-embedded building envelope for utilizing low-grade energy sources

An active pipe-embedded building envelope,which is an external wall or roof with pipes embedded inside,was presented.This structure may utilize the circulating water in the pipe to transfer heat or coolth inside directly.This kind of structure is named "active pipe-embedded building envelope" due to dealing with the thermal energy actively inside the structure mass by circulating water.This structure not only deals with thermal energy before the external disturbance becomes cooling/heating load by using the circulating water,but also may use low-grade energy sources such as evaporative cooling,solar energy,and geothermal energy.In the meantime,this structure can also improve the indoor thermal comfort by tempering the internal wall surface temperature variation due to the thermal removal in the mass.This work further presents the thermal performance of this structure under a typical hot summer weather condition by comparing it with that of the conventional external wall/roof with numerical simulation.The results show that this pipe-embedded structure may reduce the external heat transfer significantly and reduce the internal wall surface temperature for improving thermal comfort.This work also presents the effects of the water temperature and the pipe spacing on the heat transfer of this structure.The internal surface heat transfer may reduce by about 2.6 W/m2 when the water temperature reduces by 1 ℃ as far as a brick wall with pipes embedded inside is concerned.When the pipe spacing reduces by 50 mm,the internal wall surface heat flux can also reduce by about 2.3 W/m2.

基于多因素正交实验的关中民居节能优化分析

为解决陕西关中地区民居建筑围护结构热工性能不佳、采暖效率低的问题,本文以关中典型民居为研究对象,从建筑外围护结构和窗墙比方面展开关中民居节能优化分析。结合现场测试调研数据,通过DesigBuilder软件模拟能耗,探究围护结构构造和窗墙比大小对关中民居建筑热负荷、冷负荷、全生命周期投资收益比的影响,采用多因素正交实验方法耦合分析各优化方案的节能性与经济性,选出最适宜的综合节能策略。结果表明关中民居最佳节能优化策略为外墙加设80 mm厚EPS保温层、屋顶加设60 mm厚XPS保温层、外窗改用普通中空5+9A+5玻璃、北向窗墙比0.1、南向窗墙比0.3。优化后关中典型民居节能61.98%,冬季典型气象日室内平均温度上升2.78℃。

基于低损耗热压缩的新型液氢加氢站工艺系统构建

为解决国内现有液氢加氢站中核心设备短期内无法实现国产化以及液氢站加注过程中氢浪费量过大等问题,基于机械压缩增压和热压缩增压机理,构建了基于低损耗热压缩的新型液氢加氢站工艺系统,并利用Aspen HYSYS软件对该新型液氢加氢站工艺系统进行了稳态模拟,得出了系统运行工况参数,确定了优化工艺方案。在此基础上对现有液氢加氢站和新型液氢加氢站系统及其热压缩模块分别进行了能耗分析,结果表明,现有的“增压与汽化并行”式液氢加氢站系统比能耗为0.912 kWh/kg,而低损耗热压缩的新型液氢加氢站系统比能耗为0.322 kWh/kg,其比能耗比现有液氢加氢站降低了64.8%。这表明基于低损耗热压缩的新型液氢加氢站系统更节能,系统中关键部件的[火用]效率也更高。

基于气候资源禀赋的TMY权重因子调整方法研究

提出一种基于气候资源禀赋的典型气象年(TMY)权重因子调整方法。在参数间相关分析的基础上,遴选干球温度、相对湿度、日照时数与气温日较差作为分区指标,采用K-均值聚类算法对中国地域气候进行分区,依据台站所处地域的太阳能、风能等资源动态调整TMY权重因子。结果显示,调整后的权重因子构建的TMY更加精准,更能体现地域的气候特征。

Analysis of the effect of passive measures on the energy consumption and zero-energy prospects of residential buildings in Pakistan

Climate change can adversely impact the thermal comfort and energy efficiency of the buildings stock. The South Asian countries are particularly vulnerable to the adverse impacts of climate change specially in the form of rising temperatures and increasing frequency of heat waves. The passive building design measures can be useful in mitigating and adapting to the climate change by increasing energy efficiency and reducing greenhouse gas (GHG) emissions. In this study various passive climate change adaptation measures (PCAMs) have been used individually and in form of combinations in order to analyze their impact on the energy efficacy of residential buildings in Pakistan. It has been found that the natural ventilation and front green wall are the most efficient options for reducing the overall energy consumption. By implementation of these PCAMs, cooling demand can be decreased by 27.75% while heating demand can be reduced by 35%. Secondly, the prospect of net zero-energy building and reduced CO2 emissions are also studied. It has been shown that building can achieve net-zero energy on an annual basis at every orientation and it can attain the status of nearly zero-energy building on a monthly basis. Moreover, emitted CO2 can be reduced by 31% by using the renewable energy.

某调度通信楼空调系统节能减碳改造设计实践

重点介绍了某调度通信楼空调系统的节能减碳改造设计,通过综合运用余热回收、可再生能源、固体蓄热、高效制冷机房等多项技术,构建了安全可靠、绿色低碳、高效节能的空调系统。采用HDY-SMAD空调负荷计算及分析软件模拟了建筑物全年的空调能耗,并对优化前后空调系统的运行能耗和碳排放进行了测算。结果显示,优化方案空调系统全年节约电量100万kW·h,全年碳减排573 t,节能减碳效果显著。

首都住宅建筑燃料电池热电联供系统建模与能量供需分析

质子交换膜燃料电池(proton exchange membrane fuel cell,PEMFC)热电联供(combined heat and power,CHP)系统作为一种建筑供能新手段,可有效降低建筑运行能耗、推动能源绿色低碳转型。针对北方地区住宅建筑电热需求大且热电矛盾突出,全年负荷波动大等特点,以北京市为代表,利用DeST软件对住宅建筑进行负荷分析并搭建燃料电池热电联供系统模拟平台,研究不同参数对联供系统性能的影响;以负荷特性和参数分析结果为依据,设计一年不同时段下北京住宅建筑管理策略:冬季采用“以热定电”,其余季节均采用“以电定热”;与基线系统相比,在春、夏、秋、冬4个典型日中联供系统天然气耗气量分别减少了39.16%、31.63%、36.01%和14.04%,对热电联供系统用于未来建筑供能具有一定借鉴意义。

基于十年前后能耗调研的长沙地区既有住宅节能改造策略研究

长沙地区既有住宅节能改造存在居民改造意愿不强、节能改造效果不明显等问题。分别于2008年、2009年和2019年、2020年调研了湖南大学周边近35栋住宅的围护结构、家电情况与400余户居民终端用电量,采用K-means聚类法将总用电量、采暖、制冷、生活用电量分别进行聚类并计算界限值、平均值等参数,进而分析十年前后居民用电量变化规律,提出改善室内热环境与减少制冷能耗为该地区既有住宅节能改造的重要目标。对既有住宅用电量进行宏观情景预测,论证了既有住宅建筑围护结构节能改造的必要性,分析节能改造意愿不强的原因,结合目前改造现状提出适宜的相关策略。对同等气候区既有住宅节能改造具有一定参考价值。

基于EnergyPlus的玻化微珠保温砂浆保温性能模拟与对比

以典型的办公建筑为例,应用EnergyPlus软件模拟对比了玻化微珠保温砂浆和普通抹面砂浆的保温性能,由此分析了两者的保温性能及建筑节能效果.经模拟分析,在一个采暖期里,玻化微珠保温砂浆内外保温建筑的总能耗仅是普通抹面砂浆建筑的56%,采暖能耗则仅为后者的19%,且室内温度比后者要明显地高.定量化地验证了玻化微珠保温砂浆优异的保温节能效果.

基于概率性分析的混合关键级系统节能调度算法

针对混合关键级系统中的固定优先级任务节能问题,文中提出了基于概率性分析的混合关键级系统节能调度算法。混合关键级系统的实时性要求使得系统建模和分析偏向于较坏的情况。该类系统中出现任务超限的情况相对较少,易存在资源配置过度问题。通过DVFS(Dynamic Voltage Frequency Scaling)技术和混合关键级系统调度算法相结合的方式挖掘空闲时间,从而在保证系统实时性的前提下降低系统的能耗。利用MCSIMU仿真软件对所提算法进行了仿真验证,实验结果表明,对于固定优先级任务与未使用节能调度算法相比,固定优先级节能调度算法的节能率可达45%。

夏热冬冷地区综合建筑能耗敏感性分析

利用EnergyPlus软件,对夏热冬冷地区的重庆、武汉、南京、上海的建筑进行数值模拟,模拟出朝向(BO)、窗户导热系数(WinC)、窗户透光率(WVT)、墙体导热系数(WC)、墙体太阳光吸收率(WSA)、墙体比热容(WSH)、屋顶导热系数(RC)、屋顶太阳光吸收率(RSA)、屋顶比热容(RSH)共9种因素对建筑能耗的影响。首先采用全局敏感性分析,对不同因素的水平变化范围内的4000种随机组合方案进行模拟,结果表明4座城市中墙体导热系数、墙体太阳光吸收率、屋顶导热系数、窗户导热系数等4种因素对建筑能耗的影响较大;然后基于这4种主要影响因素的情况采用局部敏感性分析的方法,对4种因素进行单项优化,结果表明能耗比分别能够达到56.43%、56.83%、56.44%、55.47%。

CBE Clima Tool:A free and open-source web application for climate analysis tailored to sustainable building design

Climate-responsive building design holds immense potential for enhancing comfort,energy efficiency,and environmental sustainability.However,many social,cultural,and economic obstacles might prevent the wide adoption of designing climate-adapted buildings.One of these obstacles can be removed by enabling practitioners to easily access,visualize and analyze local climate data.The CBE Clima Tool(Clima)is a free and open-source web application that offers easy access to publicly available weather files and has been created for building energy simulation and design.It provides a series of interactive visualizations of the variables contained in the EnergyPlus Weather Files and several derived ones like the UTCI or the adaptive comfort indices.It is aimed at students,educators,and practitioners in the architecture and engineering fields.Since its inception,Clima’s user base has exhibited robust growth,attracting over 25,000 unique users annually from across 70 countries.Our tool is poised to revolutionize climate-adaptive building design,transcending geographical boundaries and fostering innovation in the architecture and engineering fields.

夏热冬暖地区办公建筑外遮阳百叶智能控制对比分析

随着建筑节能工作深入,建筑智能遮阳技术迅速发展,外遮阳智能控制系统成为有效降低建筑能耗、提高能源利用效率的新兴节能技术。通过建筑外遮阳百叶智能控制系统的对比设计,采用EnergyPlus的EMS模块进行模拟,比较东向百叶外遮阳不同智能控制方式对室内能耗的影响,对百叶最优倾角常开、入射角控制、冷负荷控制、综合控制进行能耗分析。研究结果发现:3种百叶控制方式与百叶最优倾角常开状态对比均有一定的节能效果,仅有入射角控制这一方式的总能耗最低,综合控制次之,仅有冷负荷控制的方式能耗最高。研究结果为建筑设计者提供了关于东向百叶外遮阳智能控制系统设置的参考,通过优化入射角控制设置降低能耗、提高建筑舒适性。

三江源地区超低能耗农房节能降碳技术研究

本文以青海省玛多县某一超低能耗示范农房为对象,采用TRNSYS软件对围护结构和用能设备系统开展仿真模拟研究。结果表明,采用高性能围护结构的农房可在高寒地区实现超低能耗目标;减碳技术措施方面,太阳能光伏供暖和太阳能光热供生活热水具有良好的减碳效果,空气源热泵由于高寒气候导致效率较低,在减碳方面并不具备明显优势;供暖、生活热水和照明等三项用能需求中,前两者具有较大的减碳改造潜力,特别是充分利用太阳能进行供暖和供生活热水。