Demonstration of the Nearly Zero Energy Building Concept

Nearly zero energy buildings (nZEB) will become an obligatory energy efficiency standard in Europe. Following to common guidelines in European legislation, the countries investigated technical and economic framework for the preparation of detailed national technical definition of nZEB. Slovenia accepted the nZEB criteria in early 2015. This paper describes the technical and economic background for identification of economically viable concepts of highly energy efficient apartment building. The highrise demonstration building Eco Silver House revealed that meeting nZEB standards was not an easy task, not so much for technical reasons, but mostly due to the processes, inadequate skills, not fully compliant regulation and insufficient possibilities for interaction between the building and energy networks. Analysis of cost effectiveness showed that the Eco Silver House fulfilled minimal requirements of cost-optimal for apartment building with Net Present Value of 272 EUR/m2 and Primary energy use of 79 kWh/ m2?a in line with the Slovenian national cost optimal study of minimum energy performance requirements from the year 2014. At the time, the requirement of 50% share of renewables in final energy use is not fulfilled, but will be easily reached when EU2020 energy efficiency targets set in the Slovenian Energy Act regarding the RES share in district heating systems and public power grid will be gradually implemented. The demonstration project FP7 EE-HIGHRISE confirms that in spite of the barriers, the nZEB minimum requirements defined on profound theoretical studies can be met in practice.

Uncertainty-based life-cycle analysis of near-zero energy buildings for performance improvements

Near-zero energy buildings( nZEBs) are considered as an effective solution to mitigating CO_2 emissions and reducing the energy usage in the building sector. A proper sizing of the nZEB systems( e. g. HVAC systems,energy supply systems,energy storage systems, etc.) is essential for achieving the desired annual energy balance,thermal comfort,and grid independence. Two significant factors affecting the sizing of nZEB systems are the uncertainties confronted by the building usage condition and weather condition,and the degradation effects in nZEB system components. The former factor has been studied by many researchers; however,the impact of degradation is still neglected in most studies. Degradation is prevalent in energy components of nZEB and inevitably leads to the deterioration of nZEB life-cycle performance. As a result,neglecting the degradation effects may lead to a system design which can only achieve the desired performance at the beginning several years. This paper,therefore,proposes a life-cycle performance analysis( LCPA) method for investigating the impact of degradation on the longitudinal performance of the nZEBs. The method not only integrates the uncertainties in predicting building thermal load and weather condition,but also considers the degradation in the nZEB systems. Based on the proposed LCPA method,a two-stage method is proposed to improve the sizing of the nZEB systems.The study can improve the designers "understanding of the components"degradation impacts and the proposed method is effective in the life-cycle performance analysis and improvements of nZEBs. It is the first time that the impacts of degradation and uncertainties on nZEB LCP are analysed. Case studies showthat an nZEB might not fulfil its definition at all after some years due to component degradation,while the proposed two-stage design method can effectively alleviate this problem.

Review on the recent progress of nearly zero energy building frontiers in China

Energy efficiency improvement in Chinese construction has progressed rapidly over the past two decades.Nearly zero energy buildings(NZEBs),as an integrated solution for energy-efficient construction,have gained significant attention during China's 13th Five-Year Plan period,with continuous maturation of the technical system.In this study,a research framework built upon the accomplishments of China's National Key Research and Development Program is developed,and an in-depth analysis of the most cutting-edge research is provided by thoroughly reviewing the work conducted earlier.Developing NZEB in China has been categorized into three stages based on the characteristics of technological development:(1)definition and standards,(2)demonstration and promotion,and(3)cross-domain integration.This study discerns four noteworthy development trends by examining comprehensive data spanning the last decade from 100 NZEB and zero energy building.Further,a comprehensive analysis of essential technology advancements in line with these identified trends is performed.The issues and challenges arising from the increased application of renewable energy in the context of China's carbon peak and carbon neutrality goals have also been discussed.Finally,based on this analysis,the challenges and corresponding suggestions for future research directions were proposed to help guide future studies exploring emerging trends in the NZEB field.

Contribution of nearly-zero energy buildings standards enforcement to achieve carbon neutral in urban area by 2060

Nearly-zero energy buildings (NZEB) would effectively improve building energy efficiency and promote building electrification. By using a carbon emission model integrated into a bottom-up mid-to-long term energy consumption model, this study analyzes the contribution of NZEB standards to carbon emission targets in the urban area of China by 2060. Three scenarios are set, namely BAU, steady development (S1), and high-speed development (S2). For BAU, the total carbon emissions will reach a peak of 1.94 Gt CO_(2) by 2040. In S1 scenario, total building carbon emissions will reach the peak of 1.72 Gt CO_(2) by 2030. In S2 scenario, the carbon emissions will reach a peak by 2025 with 1.64 Gt CO_(2). Under S1 scenario, which features consistency with NZEB market development and periodic improvement of building energy-efficiency standards, the carbon emission peak in 2030 will be accomplished. To achieve carbon neutrality by 2060, the upgrading of building energy standards to NZEB will contribute 50.1%, while zero-carbon electricity contribution is 49.9%. It is concluded that 2025, 2030, and 2035 could be set as mandatory enforcement years for ultra-low energy buildings, NZEB and zero energy building (ZEB), respectively.

Scientometric of Nearly Zero Energy Building Research: A Systematic Review from the Perspective of Co-Citation Analysis

As an important building type to diminish energy use and greenhouse gas emissions in the construction industry, nearly zero energy building(nZEB) has attracted much attention from many scholars, with volumes of research findings published. However, quantitative and systematic reviews on those findings are rarely conducted by researchers. Therefore, a visualized presentation regarding the advancement of nZEB research was made in this study by applying the scientometric method of co-citation analysis to 704 publications retrieved from the Web of Science database from 2006 to 2018. Here, the key conclusions drawn after the research are as follows:(1) Italy, the USA and Spain are the top three nations by the number of nZEB publications;(2) Energy and Buildings, Applied Energy and Energy are the journals with the highest number of published nZEB articles;(3) Politecnico di Milano, Aalto University and Politecnico di Torino are the most influential core organizations in the field of nZ EB;(4) Professor Kurnitski J, Professor Corgnati SP and Professor D’Agostino D are the leading nZEB experts;(5) "cost optimal", "life cycle assessment", "technical system", "design" and "indoor environment quality" are the major research directions in the field of nZEB;(6) A multi-stage optimization method for cost-optimal and nearly zero-energy building solutions in line with the EPBD 2010, co-authored by Hamdy M, is the most cited nZEB reference;(7) "residential building", "building energy saving technology", "simulation method" and "thermal comfort", etc. are the hot topics in nZEB research at present and in the future. This research is designed to provide valuable information for scholars interested in the field of nZEB.

Indoor environment of nearly zero energy residential buildings with conventional air conditioning in hot-summer and cold-winter zone

According to the few researches on Nearly zero energy residential buildings(NZERB)in hot-summer and cold-winter zone,although it could reduce the cooling load of buildings due to its high thermal insulation and air tightness,it still needed for certain cooling in summer.This paper studied indoor environment of NZERB un-der three kinds of air-conditioners(split-type air-conditioner,multi-line air-conditioner and ceiling radiant air-conditioner).Firstly,a simulation model of NZERB was established based on Nanjing,a typical city in hot-summer and cold-winter zone.Secondly,variation of indoor air temperature and building load characteristics with outdoor air temperature were studied.Thirdly,indoor environment and energy consumption under three selected con-ventional air-conditioners in summer were simulated.Finally,the discussion was given,and an air-conditioner combining with convective and radiant cooling were proposed.The results indicated that the air-conditioner needed to be turned on in NZERB in hot-summer and cold-winter zone due to the room air temperature in off-air condition ranged from 32℃to 36℃,which was higher than designed indoor environment temperature in sum-mer,but the indoor environment of NZERB under three selected conventional air-conditioners could not meet the requirements of energy saving and comfort at the same time,and a proposed convective-radiant air-conditioner could be fast,stable,and energy saving.The findings can provide a reference for conducting active technology in NZERB.

沈阳地区典型办公建筑运行阶段碳减排潜力研究

以沈阳某办公建筑为例,将GB 50189—2015《公共建筑节能设计标准》作为节能基准,对比分析多种近零能耗建筑技术情形对建筑碳排放的影响,并对其碳减排潜力进行评估测算。利用模拟软件Design Builder对沈阳市某办公建筑建立典型模型,通过模拟计算得到几种不同技术情形下的能耗强度。碳排放强度由不同类型能源碳排放因子与能耗强度计算得出。结果表明:可再生能源利用技术和暖通空调设备能效提升技术可明显减少碳排放,碳减排率分别可达到44.88%和39.99%;另外,建筑围护结构改造以及自然通风和自然采光结合技术,减排率分别为8.18%、7.22%。按照近零能耗建筑技术要求,综合6种技术情形,办公建筑运行阶段的减排率可达51.08%。

基于BIM技术寒冷地区近零能耗农宅技术经济分析

随着“双碳”目标的提出,观念从节能减排、低碳环保提升到近零能耗建筑的建设,近零能耗建筑一词也正式进入我们的视野里,针对于寒冷地区高耗能、高排放的现状,发展推进近零能耗建筑已经成为必然趋势,根据实例运用BIM技术进行近零能耗农宅Revit建模,运用Mars进行渲染,对应项目进行节能技术分析,导入广联达软件进行工程算量计价,从而对普通农宅和近零能耗农宅的保温系统、门窗工程、太阳能系统和新风系统进行经济造价对比分析,为在寒冷地区建设近零能耗农宅提供数据支持和帮助。

寒冷地区近零能耗建筑参数优化研究

针对寒冷地区近零能耗建筑的围护结构在夏季会增加室内制冷能耗的问题,提出在夏季和过渡季采用空调与自然通风系统相结合的节能方法,运用EnergyPlus软件模拟研究窗墙面积比、外窗太阳得热因数、窗户传热系数、外墙传热系数、外遮阳悬挑梁长度等5个参数对建筑能耗的影响,通过正交试验确定最优因素水平组合.研究结果显示,优化建筑与既有建筑相比,全年供暖制冷综合能耗可节约43.7%.

近零能耗建筑发展简述

随着城镇化的高速发展,建筑业规模不断扩大,建筑能耗在全社会总能耗中的比重也在逐年增加。作为影响环境的一个重要方面,能耗问题历来受到各国的重视。如何降低建筑能耗需求,成为城镇发展过程中不可避免的问题。主要总结了各国在低能耗建筑实践过程中的经验与成果,同时介绍了我国关于低能耗建筑的相关政策标准,讨论了近零能耗建筑在我国发展的难点并提出相关建议,以期推动建筑行业绿色、低碳发展。

近零能耗居住建筑围护结构性能研究

研究近零能耗居住建筑围护结构的力学性能和保温性能,有利于为现场施工相变材料掺量提供理论依据。以硬脂酸和月桂酸为相变材料制备相变混凝土砂浆,研究了不同相变混凝土围护结构的性能变化。结果表明,随着相变复合体系替代比例的增加,相变混凝土围护结构的密度、塌落度、抗压强度、抗拉强度、墙体中心温度峰值和侧面温度峰值均下降。相变复合体系替代比例为30%时,相变混凝土围护结构满足C45的强度等级要求,相比普通混凝土,相变混凝土围护墙体中心温度峰值降低幅度为9.7%,侧面温度峰值降低幅度为12.4%。相变复合体系替代比例为50%时,相变混凝土围护结构满足C30的强度等级要求,相比普通混凝土,相变混凝土围护墙体中心温度峰值降低幅度为16%,侧面温度峰值降低幅度为23.5%。

被动式近零能耗建筑日耗热量预测仿真

由于被动式近零能耗建筑实际日耗热量受多种因素影响、特征难提取,导致日耗热量预测难度较大。为此,提出一种基于离散稀疏函数的建筑实际日耗热量预测方法。采用离散稀疏函数计算历史建筑日耗热量数据,在不同维度层次上特征向量和稀疏参数,利用激活函数建立偏离惩罚项,明确每个热量先验信息数据与中心值间的偏离度。采用线性传递函数求得会影响实际日耗热量间的线性变化关系,建立时间序列,采用自回归算法得出时间和热量的正向变化序列,实现对日耗热量的预测。实验数据证明,所提方法日耗热量预测精准度较高,针对热负荷、冷负荷以及预测平均评价(Predicted Mean Vote, PMV)指标均实现了高效预测。

近零能耗建筑电气设计简析

结合实际工程项目,依据GB/T 51350-2019《近零能耗建筑技术标准》相关设计标准要求,从电气管线气密层敷设、光伏发电、LED光电玻璃、监测和控制、能效指标判定等方面论述近零能耗建筑电气的相关设计,简析标准要求的电气技术措施。

夏热冬冷地区近零能耗建筑技术——以台州数字科技园科技秀场、产业服务中心为例

随着全球气候变化和能源资源紧张的形势日益严峻,近零能耗建筑成为全球建筑领域的研究和发展重点。本研究旨在探索夏热冬冷地区近零能耗建筑的实施技术,其中包括围护结构、节能设备以及可再生能源的利用等,同时分析其在能源消耗和环境保护方面的效益。

近零能耗建筑技术应用与经济分析

面对全球能源日益短缺、空气污染日益严重的情况,发展近零能耗建筑作为建筑节能的新方向尤为必要。文章以上海某办公楼为例,具体分析了非透光围护结构保温技术、透光围护结构(外窗)保温技术、被动式节能技术、主动式节能技术、可再生能源技术及装配式技术的实际应用。研究发现,近零能耗建筑的建造成本较传统建筑有一定的增加,但其运营成本有所减少,因此从长远角度看,近零能耗建筑在实际应用中具有可行性和实际的推广价值。

基于多因素耦合风、光、能耗的寒冷地区多层住区节能规划设计研究

建筑规划是影响建筑能耗的重要因素,通过对建筑规划方案进行优化设计,可以有效降低建筑本体能耗。采用多因素耦合室外风环境、光环境以及建筑总能耗的模拟计算方法,计算分析了正向间距、侧向间距、朝向、建筑密度和布局形式对建筑能耗的影响。采用正交设计和极差分析的方法,得出建筑朝向对能耗影响最大,F值为1,建筑密度对能耗影响最小,F值为0.005。通过计算各因素水平对应指标的均值可以找到接近最优的建筑布局,即正向间距40 m、侧向间距18 m、朝向为正南、建筑密度为22.5%、建筑布局为行列式。相对于其他的布局形式最大可实现节能10%。研究成果为寒冷地区多层住区的节能规划设计方法和关键数据指标的确定提供了参考。

光伏直驱变频多联机在严寒地区的经济性与碳排放量分析

在严寒地区,极端的气候条件和辐照强度的不稳定性给光伏直驱变频多联机的运行带来挑战。通过监测光伏直驱变频多联机在严寒地区近零能耗办公建筑中的运行情况,对实验期间的运行能耗进行分析。结果显示:光伏直驱变频多联机系统在实验期间的运行成本比普通多联机空调系统节省了约55.81%,经济效益显著。光伏直驱变频多联机系统的静态回收期小于10年。在建筑设计寿命20年以内,光伏直驱变频多联机系统的碳排放量比普通多联机空调系统降低了约56.95%,降碳效果明显。

西北寒冷地区近零能耗建筑技术应用——以兰州新区某办公楼为例

经济的发展、人居环境质量的提升等都依赖于能源,而我国的能源消耗总量逐年增加,节能减排任重道远。近零能耗建筑技术凭借其节能、低碳的优势,逐渐被应用到各个国家和地区的节能建筑实践中。以兰州新区某办公楼为例,较为系统地介绍了近零能耗建筑技术首次在西北寒冷与欠发达地区节能建筑中的应用实践,旨在借鉴该项目的成功经验,为后续同类地区的新建节能建筑及既有建筑节能改造等提供技术支撑,推动节能减排等可持续事业的发展。

深圳地区某近零能耗学校设计探讨

以深圳地区某学校项目为案例,对近零能耗建筑相关技术难点进行了分析论证,并提出多项运维、科普措施:采用分体空调的教室设置集中新风系统;利用EnergyPlus软件进行模拟计算,证实热回收装置在深圳地区不具有经济性,新风系统不设置热回收装置;编制近零能耗建筑运行管理手册和师生个人节能减排行为建议书,并结合课程进行知识科普,倡导师生行为节能。

近零能耗建筑设计实践——以福建省漳州市东山发展广场为例

“双碳”背景下,探索近零能耗建筑技术是建筑领域发展的必然趋势。通过研究近零能耗建筑技术在福建省漳州市东山发展广场的应用,以“被动优先,主动优化,低碳能源”为设计理念,在高效供暖空调设备、高效照明系统、节能电梯系统、太阳能光伏发电系统、风力发电系统等方面采用了系统的节能减排技术措施,可知充分利用当地优势资源进行建筑节能设计是该地区近零能耗建筑设计的有效途径之一。项目的实施契合国家“双碳”战略发展方向,对指导我国夏热冬暖地区实现建筑节能,大幅度推进建筑碳减排,具有重要的示范意义与推广价值,为同类型项目提供了可行的参考模板。