EcoShopping： Energy Efficient and Cost Competitive Retrofitting Solutions for Retail Buildings in Europe

The ＂EcoShopping＂ project aims to produce a practical holistic retrofitting solution for commercial buildings, reduce primary energy consumption to less than 80 kWh/（m2.year） and increase the proportion of RES （renewable energy systems） to more than 50% by using state of the art solutions. The project intends to use and integrate available products and technologies; along with a network to accurately monitor the environmental and occupancy parameters to allow the building management system to have better control of the building and fully exploit the thermal mass. This paper introduces the EcoShopping project and the consortium carrying out the work, describes the case study building and the initial targets for carbon reduction, and discusses the results of Work Package 2： which is an assessment of national building codes, EPBD （energy performance buildings directive） implementation, performance standards and good practice.

Strategy for Energy Efficiency Retrofit of Rural Buildings in Hot-summer and Hold-winter Zone——A Case Study in Xinjiang New District,Jiangxi

Under the background of new urbanization, rural buildings＇ energy efficiency retrofit is an essential part of the overall work of the building energy conservation. Therefore, taking rural buildings in hot-summer and cold-winter zone as the research object, we carried out field investigation by combining geographical climate charactedstics with social-economic conditions and analyzed the energy consumption and energy conservation of rural buildings in hot-summer and cold-winter zone. On the basis of the investigation and analysis, this paper pointed out the questions with its energy efficiency retrofit and proposed the energy-saving strategy which was suitable for rural buildings in hot-summer and cold-winter zone based on people＇s livelihood and development.

Optimal retrofitting scenarios of multi-objective energy-efficient historic building under different national goals integrating energy simulation,reduced order modelling and NSGA-II algorithm

Retrofitting a historic building under different national goals involves multiple objectives,constraints,and numerous potential measures and packages,therefore it is time-consuming and challenging during the early design stage.This study introduces a systematic retrofitting approach that incorporates standard measures for the building envelope(walls,windows,roof),as well as the heating,cooling,and lighting systems.Three retrofit objectives are delineated based on prevailing Chinese standards.The retrofit measures function as genes to optimize energy-savings,carbon emissions,and net present value(NPV)by employing a log-additive decomposition approach through energy simulation techniques and NSGA-II,yielding 185,163,and 8 solutions.Subsequently,a weighted sum method is proposed to derive optimal solutions across multiple scenarios.The framework is applied to a courtyard building in Nanjing,China,and the outcomes of the implementation are scrutinized to ascertain the optimal retrofit package under various scenarios.Through this retrofit,energy consumption can be diminished by up to 63.62%,resulting in an NPV growth of 151.84%,and maximum rate of 60.48%carbon reduction.These three result values not only indicate that the optimal values are achieved in these three aspects of energy saving,carbon reduction and economy,but also show the possibility of possible equilibrium in this multi-objective optimization problem.The framework proposed in this study effectively addresses the multi-objective optimization challenge in building renovation by employing a reliable optimization algorithm with a computationally efficient reduced-order model.It provides valuable insights and recommendations for optimizing energy retrofit strategies and meeting various performance objectives.

Modeling the energy retrofit decision in commercial office buildings

Retrofitting existing buildings has emerged as a primary strategy for reducing energy use and carbon emissions, both nationally and in cities. Despite the increasing awareness of retrofitting opportunities and a growing portfolio of successful case studies, little is known about the decision-making processes of building owners and asset managers with respect to energy efficiency investments. Specifically, the research presented here examines the effects of ownership type, tenant demand, and real estate market location on building energy retrofit decisions in the commercial office sector. This paper uses an original, detailed survey of asset managers of 763 office buildings in nineteen cities sampled from the CBRE, Inc. portfolio. Controlling for various building characteristics, the results demonstrate that ownership type and local market do, in fact, influence the retrofit decision.Overall, this analysis provides new evidence for the importance of understanding ownership type and the varying motivations of differing types of owners in building energy efficiency investment decisions. The findings of both the survey analysis and the predictive model demonstrate additional support for the targeting of energy efficiency incentives and outreach based on ownership entity, local market conditions, and specific physical building characteristics.

Energy retrofit and conservation of a historic building using multi-objective optimization and an analytic hierarchy process

When deciding on the best historic building retrofit,energy savings and thermal comfort can be quantitatively evaluated using an energy model,whereas conservation compatibility is intrinsically qualitative and reflects the perspective of the local heritage authority. We present a methodology that permits finding and comparing optimal retrofits for historic buildings in a multi-perspective and quantitative way. We use an analytic hierarchyprocess to quantify conservation compatibility by distilling a conservation score from the opinions of 10 experts in the field. This score,along with energy needs for heating and cooling and thermal comfort,are the three targets of a multi-objective optimization aimed at identifying optimal retrofits for a medieval building in the north of Italy,destined to become a museum. Retrofit measures considered were different kinds of external and internal envelope insulation,improvement of airtightness,replacement of windows,and ventilative cooling. The result is a portfolio of optimal retrofits that cover the whole range of conservation compatibility. We showthat in the analyzed case heritage preservation is compatible with a four-fold reduction in energy needs at a high thermal comfort level. Even higher energy savings are only achievable at the cost of heritage degradation.

Differential nonlinear photocarrier radiometry for characterizing ultra-low energy boron implantation in silicon

The measuring of the depth profile and electrical activity of implantation impurity in the top nanometer range of silicon encounters various difficulties and limitations, though it is known to be critical in fabrication of silicon complementary metal–oxide–semiconductor(CMOS) devices. In the present work, SRIM program and photocarrier radiometry(PCR)are employed to monitor the boron implantation in industrial-grade silicon in an ultra-low implantation energy range from 0.5 keV to 5 keV. The differential PCR technique, which is improved by greatly shortening the measurement time through the simplification of reference sample, is used to investigate the effects of implantation energy on the frequency behavior of the PCR signal for ultra-shallow junction. The transport parameters and thickness of shallow junction, extracted via multi-parameter fitting the dependence of differential PCR signal on modulation frequency to the corresponding theoretical model, well explain the energy dependence of PCR signal and further quantitatively characterize the recovery degree of structure damage induced by ion implantation and the electrical activation degree of impurities. The monitoring of nmlevel thickness and electronic properties exhibits high sensitivity and apparent monotonicity over the industrially relevant implantation energy range. The depth profiles of implantation boron in silicon with the typical electrical damage threshold(YED) of 5.3×10^(15)cm^(-3) are evaluated by the SRIM program, and the determined thickness values are consistent well with those extracted by the differential PCR. It is demonstrated that the SRIM and the PCR are both effective tools to characterize ultra-low energy ion implantation in silicon.

A Methodology for Introducing M&V Adjustments during an Energy Retrofit Impact Assessment

The assessment of an energy retrofit necessarily requires an energy measurement campaign before (base year energy consumption) and after (post retrofit energy consumption) the retrofit. Only in this way is it possible to reach a safe conclusion, on the true retrofit impact. In addition, a number of adjustments are necessary to secure that the retrofit impact on energy consumption is effectively isolated, i.e., which we report on the true retrofit impact and not, for example, on external variations, such as a more mild winter. This paper introduces a conceptual framework for taking account, in the retrofit impact assessment, of three external parameters: weather, indoor comfort and space occupancy. The broader strategy behind this work is to develop a comprehensive methodology that would allow a cost efficient, fast and accurate assessment of energy retrofits in buildings. This would allow insight, on the investor side, as to the prudence of his investment and, and in this way, could help the proliferation of the practice of energy retrofits. The adjustment methodology, introduced here, is a first step in this direction.

Discussion on the Intelligent Design of Ultra-Low Energy Consumption Passive Buildings

With the continuous development of science and technology and the gradual improvement of modem building technology, people pay more and more attention to the introduction of advanced technology in architectural design, such as the application of intelligent technology. With the increasingly severe environmental situation, people are increasingly demanding the environmental performance and green performance of buildings. The establishment of ultra-low energy consumption passive buildings has become one of the key construction contents of construction projects. This paper mainly analyzes the design points and architectural forms of related buildings from the perspective of intelligent control.

An adjusted energy-saving quantity calculation method for building energy-efficient retrofit

Aiming at a comprehensive assessment of energy-saving retrofitting effect on existing buildings,a calculation method is developed to adjust energy-saving quantity in standard condition for comparison under the same conditions. A mathematical model,method theory and calculation steps are given. Error analysis results show that this method can be applied accurately to practical engineering projects. In a case study of energy-saving quantity assessment before and after retrofitting on a certain hospital in Shanghai,with energy simulation software TRNSYS,detailed application of this method is introduced and analyzed. The method is applied to the case of energy-saving quantity assessment to a hospital in Shanghai before and after retrofitting with the energy simulation software TRNSYS.

基于类型学方法的城镇住宅节能改造效果的分类评估——以重庆市为例

针对城镇住宅量大面广、复杂多样、能效偏低且参差不齐的现况,基于类型学方法,以重庆市1950—2000年间的城镇住宅为例,采用CHAID决策树算法,按照建造年代、住宅套型和套型组合三种属性,从373例样本中归纳出围护结构的三个大类和24个子类,并构建原型的物理模型。模拟分析表明:分类评估可以更好地解释不同建筑类型冷、热负荷需求的影响因子及其显著程度,筛选出最不节能的类型及各类型最不利于节能的部位;不同类型住宅的冷、热负荷节约率取决于节能改造后不同部位的贡献度。推荐运用CHAID决策树算法对节能改造评价标准进行类型化细分,并扩展至更大区域范围的能效评估和改造潜力预测。

北京市某公共建筑综合节能改造与能效评估

以北京市东城区某综合园区为例,根据园区现状对其围护结构热工性能、供暖空调、建筑照明及用水器具进行节能诊断及能耗分析。结果显示:建筑供暖耗热量及照明耗电量占比分别为58.96%和10.24%,为挖掘改造潜力并确定基准能耗提供了依据;通过围护结构保温层加装、门窗更换、高效空调设备更换、照明灯具更换及节水器具更换等节能技改措施进行综合节能改造,计算改造后能耗;将不同能源类型能耗归一化为标煤,经测算,改造后项目节能量约为71.0 tce,综合节能率35.52%,减少向大气排放二氧化碳175.38 t,节能减排效果显著,为类似地区公建节能改造提供了借鉴和参考。本次能评估多采用理论模拟计算方法,还需改造后实际运行数据对比支撑。

基于能量平衡的既有建筑结构抗震加固性能化设计方法研究

由于规范标准对结构抗震设计要求的不断提高以及结构在长期服役过程中性能的逐渐劣化,既有建筑结构的抗震性能不再满足设计要求,开展其抗震加固设计研究势在必行。然而,目前的加固设计方法往往需要大量的非线性动力计算反复迭代,增加了设计的难度,降低了其适用性。基于能量平衡概念,提出适用于增设消能减震装置的既有建筑结构抗震加固性能化设计方法。该方法考虑了多地震水准性能目标,设计过程中无需开展非线性动力计算,且迭代次数少。采用所提方法对Benchmark钢框架结构进行加固设计,通过非线性动力分析评估了加固前和加固后结构的抗震性能。研究结果表明:加固后,所有楼层的位移角均明显降低,小震、中震和大震时的平均降幅约为20%,可见加固后结构抗震性能得到了显著改善;加固结构在小震、中震和大震下的层间位移角均与设计值吻合,实现了预期的层间位移角和屋顶位移角目标,验证了所提方法的有效性;所提方法设计的阻尼器在小震时整体保持弹性状态,在中震和大震时进入屈服耗能状态,实现了预期的耗能机制,且阻尼器延性需求沿楼层的分布较为均匀,进一步表明了设计方法的合理性。研究成果可为既有建筑结构的抗震性能加固设计提供参考。

Measurement and analysis of airtightness safeguard measures for typical ultra-low energy buildings

Zero-energy buildings constitute an effective means of reducing urban carbon emissions.High airtightness,a typical characteristic of zero-energy building,is closely related to the building’s air infiltration and has a signifi-cant impact on the performance of the building envelope,indoor air quality,building energy consumption,and efficient operation of air-conditioning systems.However,thus far,systematic developments in high-airtightness assurance technologies remain scarce.Most existing studies have tested the airtightness of buildings and typical building components;however,in-depth analyses into the formation of infiltration have not been reported.There-fore,for realizing zero-energy buildings,ensuring airtightness is an urgent problem that needs to be addressed.Accordingly,in this study,based on several building airtightness measurement studies,the typical air leakage paths in buildings were summarized,and the causes of typical air leakage components in buildings were further analysed by tracing construction processes.Moreover,targeted measures for airtightness in buildings were estab-lished and applied to practical cases.Lastly,the resulting improved building airtightness was measured and the results show that the airtightness of the measured ultra-low energy consumption buildings ranges from 0.13 h^(−1)to 0.57 h^(−1),with a mean value of 0.32 h^(−1).The effectiveness of the airtightness safeguard measures was verified.This study serves as a basis for the assumption of the air leakage path distribution when simulating building air infiltration and also provides a design reference for improving the construction technologies and airtightness of buildings.

住宅建筑超低能耗改造设计及碳排放对比研究

近年来,超低能耗建筑和近零能耗建筑获得了越来越多的关注。随着国家由增量转存量的建筑节能目标转变,针对住宅建筑的节能改造呈现出巨大的潜力。以寒冷地区典型住宅建筑为案例,进行超低能耗节能改造设计及碳排放测算对比研究。设置30组外墙保温方案、30组屋面保温方案、4组外窗类型方案进行模拟,并基于模拟结果采用敏感性分析进行方案比选。相较基准建筑和改造前建筑,综合最优方案的节能率分别为57.1%、72.1%。采用碳排放因子法对改造前建筑及58组模拟方案进行碳排放测算,可知改造后建筑运行阶段的碳排放量可降低84.2%,并基于测算结果对改造设计方案进一步优化,为既有住宅的超低能耗节能改造提供理论与实践参考。

既有建筑水泥基外围护系统低碳改造技术研究

既有建筑水泥基外围护系统存在开裂、渗漏、脱落、空鼓和高能耗等问题,为保障其安全及功能性,开展既有建筑外围护系统低碳改造是重要解决办法。系统介绍了既有建筑外保温缺陷形成原因,厘清外保温缺陷检测技术,提出外保温风险评估流程和风险等级划分方法,明确外保温低碳设计计算理论。针对外保温不同缺陷类型,提出不同的施工工艺流程及注意事项,为既有建筑外保温低碳改造技术应用推广提供借鉴与参考。

基于合同能源管理模式的云机房节能改造方案设计及经济性分析

以北京市朝阳区某云机房为例,调研机房现状空调情况,分析电量电费数据。针对系统存在的制冷能效低、运行费用高、通风散热差等问题,提出加装6个制冷量为50kW的风冷氟泵冷却模块及采用高压雾化喷淋系统两项改造措施,并基于15年期合同能源管理模式,计算项目动态投资回收期,评判项目投资回收风险。测算结果表明,机房年均节电量306.55 MWh,节能率35.25%,减排二氧化碳93.06t,改造后机房PUE值由1.82降至1.58;工程投资额151.8万元,年均节约费用26.98万元,税后内部收益率13.18%,动态投资回收期7.22年;节能环保效益及经济效益较好,以期为园区乃至北京市类似机房升级改造提供参考和借鉴。

温和地区既有公共建筑超低能耗改造方法研究——以云南建筑技术发展中心节能改造设计为例

20世纪末的既有公共建筑相对于参照建筑的节能率普遍较低,远未达到现行节能标准,使用时达到一定的舒适度需要消耗较多能源。为了推进云南省温和地区城市更新中的既有建筑节能改造标准编制,进一步完善既有公共建筑节能降碳改造指南,通过对典型案例云南建筑技术发展中心办公楼进行了超低能耗改造设计研究,以模拟计算数据和实际检测数据为依据,系统地剖析了温和地区既有公共建筑超低能耗改造的性能化设计方法和独特构造设计措施。结果表明:云南温和地区的节能改造措施有别于其他气候区,改造成本相对较低;通过对外围护结构进行得当的节能改造和增强气密性,能耗指标将大幅度降低且舒适度提高,可以达到超低能耗建筑节能标准。

A high-performance electromagnetic energy harvester for scavenging ultra-low frequency vibration energy of human foot movement

In our daily lives,low-frequency kinetic energy primarily manifests as vibrations.However,effective harnessing of lowfrequency kinetic energy remains a formidable challenge.This paper proposes a rope-driven rotor that rotates around an axis and consists of an ultra-high-molecular-weight polyethylene(UHMWPE)wire wrapped around a metal shaft.The rotor can convert ultra-low frequency vibration/linear motion into rapid rotation by pressing the top at low frequencies and driving the rope for a quick release.The harvester can generate up to 36.25 m W power using a 0.1-mm-diameter UHMWPE wire as the rotor when periodically pressed down to 20 mm at a frequency of 1 Hz.A simple power generation floor is assembled,generating 28.58-m W power with a matching load at a frequency of 1.5 Hz.Moreover,the harvester can increase the charging voltage of a 0.47-F supercapacitor from 0 to 6.8 V within 10 min.In addition,the harvester can harvest energy through a light finger press motion,and the energy obtained can also support the continuous operation of multiple electronic devices concurrently.This study introduces an effective method for harvesting ultra-low frequency energy and has great prospects in the field of power generation floor and human movement energy harvesting.

Potential of GSHP coupled with PV systems for retrofitting urban areas in different European climates based on archetypes definition

According to the recent policies regarding energy use in buildings and the need of retrofit strategies,the aim of this work is to support policies concerning the installation of ground source heat exchangers in urban and historical areas,raising the awareness on the potential energy saving achievable with optimal sizing and limited impact on the urban environment.Archetypes have been developed distinguishing among existing and historic buildings,focusing on single-family terrace houses,which are the typical residential buildings in European historic centres.A methodology for the optimal sizing of ground source heat pumps,eventually considering dual-source system or air system has been developed combining simulations of a photovoltaic system to estimate the self-sufficiency and the self-consumption for five orientations of the building.Extreme results have been obtained for warm cli-mates,with negligible heating energy demand and possibly free cooling systems rather than traditional cooling systems needed in wintertime.Penalty temperature was acceptable despite unbalanced energy demands.With proper inclination,photovoltaic systems could provide up to 40%of self-sufficiency share also in northern cli-mates.An energy-economic analysis was carried out obtaining a variety of cases representing a general overview of the European building stock and the potential benefits achievable in terms of renewable energy share,energy savings and economic investments needed to be extended to simulations at urban scale.

北京某宾馆改造采用辐射空调制冷效果分析

国内辐射空调技术应用于新建住宅、办公建筑的实例较多,应用于改造项目的实例较少。北京某宾馆改造采用了辐射+新风的空调系统形式,空调末端采用吊顶辐射板+地面辐射盘管+顶送风,冷热源采用空气源热泵,制冷工况时空气源热泵供出的低温冷水一部分进新风机组,另一部分进辐射用混水设备。2022年7月对项目的空调系统制冷工况进行了测试。给出一定运行策略下宾馆典型房间的温湿度,以及整个制冷系统能效的实测情况,并对典型房间的冷负荷进行了模拟计算。综合测试及模拟计算结果,给出系统运行建议,并对其整个空调季制冷系统能耗指标进行了预测。