Energy and Buildings最新文献_第8页

Best practices of techno-economic methods for solar photovoltaic coupled heat pump analysis in cold climates

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Energy and Buildings

Pub Date : 2025-02-01 DOI: 10.1016/j.enbuild.2024.115196

Shafquat Rana , Nelson Sommerfeldt , Joshua M. Pearce

One of the most promising methods of decarbonizing the global building heating and cooling load is with solar photovoltaic (PV) powered heat pumps (HP). The complex nature of these systems and the interdependent interactions between each technology and the energy markets involve various sophisticated models to simulate accurately. This often leaves model descriptions lacking, particularly when qualitative discussion is required. This article reviews the models that exist and provides best practices for designing and simulating PV + HP systems of various complexities. The key performance indicators for electricity generation and total life cycle cost are summarized. This article then provides a detailed and comprehensive method for the techno-economic analysis of heat pumps powered with PV using an example of North American cold climates. For each component of the system, a model and boundary condition are described, and motivations are explained, as well as descriptions of alternatives and motivations for not using them. The result shows a method that combines five disparate models across multiple computer programs into a single analysis that produces critical metrics for technical, economic, and climate impact analysis. This paper identified the best practices for building energy demand and supply simulation with a particular focus on prosumer electrification via PV and HPs. This model is generalizable and the economic and policy implications of replacing fossil fuel heating with solar-powered heat pumps in both rural and urban areas that are discussed here, and future work is proposed to eliminate natural gas used for heating. High-leverage opportunities exist to enhance support for the development of free and open-source integrated systems modeling tools as well as open data to provide transparent trusted results to help guide policymakers and investors.

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引用次数: 0

Developing a co-benefits evaluation model to optimize greening coverage designs on university campuses in hot and humid areas 开发协同效益评估模型，优化湿热地区大学校园绿化覆盖设计

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Energy and Buildings

Pub Date : 2025-02-01 DOI: 10.1016/j.enbuild.2024.115214

Xiaoqing Zhou , Simin Deng , Yongbo Cui , Chengliang Fan

The thermal environment of university campuses significantly impacts human comfort and building energy consumption, particularly in regions with hot and humid climates. Optimizing green space can effectively alleviate high-temperature issues and enhance cooling effects (

E_{c}

), ventilation effects (

E_{v}

), and carbon sequestration benefits (

C_{s}

). Given the limited land resources in campus areas, it is critical to optimize the design of green spaces to maximize their multiple benefits. This study aims to propose co-benefits evaluation model for optimizing campus green coverage ratios (GCRs), employing the CRITIC weighting method, while considering multiple evaluation indicators (i.e.,

E_{c}

,

E_{v}

,

C_{s}

, and plantation management costs (

M_{c}

)). This study used ENVI-met software to simulate and quantify the outdoor environmental effects of various GCRs scenarios in a Guangzhou university campus, a typical hot-humid area in China. The model’s accuracy was validated against on-site measurements. Results revealed a parabolic relationship between co-benefits and GCRs. As GCRs increased from 10 % to 47 %, co-benefits gradually decreased from 0.48 to 0.40. Subsequently, with additional GCR increases, co-benefits rose to 0.52, reaching a maximum enhancement of 21.6 %. Moreover, co-benefits improved by about 1.2 % to 9.3 % for each 10% increase in GCR. The GCRs exhibited positive correlations with

E_{c}

,

C_{s}

and

M_{c}

, and negative correlations with

E_{v}

. Compared to 10 % GCR scenario, the air temperature, wind velocity, and CO₂ concentration in 90 % GCR scenario decreased by 8.7 %, 44.3 %, and 1.62 %, respectively, and plantation management costs were increased by 90.4 %. This study offers valuable guidance for optimal campus green space design, promoting low-carbon and comfortable educational environments.

大学校园的热环境对人体舒适度和建筑能耗有显著影响，特别是在湿热气候地区。优化绿地可以有效缓解高温问题，提高降温效果（Ec）、通风效果（Ev）和固碳效益（Cs）。在校园土地资源有限的情况下，如何优化绿地的设计，使绿地的多重效益最大化是至关重要的。本研究旨在采用CRITIC加权法，综合考虑Ec、Ev、Cs和人工林管理成本等多个评价指标，提出优化校园绿化覆盖率的协同效益评价模型。本研究采用ENVI-met软件对中国典型湿热地区广州大学校园不同gcr情景的室外环境效应进行了模拟和量化。通过现场测量验证了模型的准确性。结果显示，共同效益与gcr之间呈抛物线关系。随着gcr从10%增加到47%，协同效益从0.48逐渐下降到0.40。随后，随着GCR的进一步增加，共同效益上升到0.52，达到21.6%的最大增强。此外，GCR每增加10%，共同效益提高约1.2%至9.3%。GCRs与Ec、Cs和Mc呈正相关，与Ev呈负相关。与10% GCR情景相比，90% GCR情景的气温、风速和CO2浓度分别降低了8.7%、44.3%和1.62%，人工林经营成本增加了90.4%。本研究为优化校园绿地设计，营造低碳舒适的教育环境提供了有价值的指导。

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引用次数: 0

Development and application of a digital twin model for Net zero energy building operation and maintenance utilizing BIM-IoT integration 利用BIM-IoT集成的净零能耗建筑运维数字孪生模型的开发与应用

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Energy and Buildings

Pub Date : 2025-02-01 DOI: 10.1016/j.enbuild.2024.115170

Zhansheng Liu, Mingming Li, Weiyu Ji

Net Zero Energy Buildings (NZEB) represent a significant opportunity to reduce building energy consumption and achieve the climate and energy goals that will be necessary in the future. Nevertheless, the effective operation and maintenance (O&M) management of NZEB remains a significant challenge. This is largely due to the inadequate management of the O&M phase and the lack of comprehensive data integration and application. Accordingly, this study proposes an O&M digital twin modeling approach for integrating data in the O&M phase of NZEB and realizing efficient management. The twin modeling process comprises data collection, model construction, simulation analysis, and validation iteration. Empirical evidence demonstrates that the proposed twin model markedly enhances the utilization efficiency of O&M data, facilitating the perception, visualization, and automated feedback control of NZEB. The proposed digital twin modeling method offers technical guidance for O&M managers seeking to achieve efficient O&M management of NZEB.

净零能耗建筑（NZEB）是减少建筑能耗、实现未来气候和能源目标的重要机遇。然而，对 NZEB 进行有效的运营和维护（O&M）管理仍然是一项重大挑战。这主要是由于对运行和维护阶段的管理不足，以及缺乏全面的数据整合和应用。因此，本研究提出了一种 O&M 数字孪生建模方法，用于整合 NZEB O&M 阶段的数据并实现高效管理。孪生建模过程包括数据收集、模型构建、模拟分析和验证迭代。实证证明，所提出的孪生模型显著提高了运行和监测数据的利用效率，促进了对新西兰国家地震工程的感知、可视化和自动反馈控制。所提出的数字孪生建模方法为运行与监测管理者提供了技术指导，帮助他们实现对新西兰国家地震局的高效运行与监测管理。

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引用次数: 0

Advanced building envelope by integrating phase change material into a double-pane window at various orientations

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Energy and Buildings

Pub Date : 2025-02-01 DOI: 10.1016/j.enbuild.2024.115140

Qudama Al-Yasiri, Ahmed Kadhim Alshara, Murtadha Al Sudani, Ali Al Khafaji, Mohammed Al-Bahadli

Considering building envelope elements in hot locations, windows contribute to about one-third of the building’s total cooling load since heat is transferred effortlessly through transparent elements more than opaque ones. The present work experimentally explores the energy advancements of a phase change material (PCM) loaded in the air gap of a double-pane window. The PCM window was examined under Southern Iraq weather conditions and compared with an identical air–gap double-pane window at various orientations. Numerous energy indicators were analyzed, including the improvement in the average indoor temperature, attenuation coefficient, and time delay to quantify the PCM’s usefulness to the built environment at different orientations. Study outcomes depicted remarkable energy improvements for the PCM in all orientations over the reference window in which the indoor temperature was reduced as much as 23 °C, and shifted by up to 50 min over the reference case. Conclusively, the PCM window could notably shave peak temperature when exposed to high solar radiation for a short period, while it could shift peak temperature mostly if oriented towards longtime solar radiation.

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引用次数: 0

Multiple-scale urban form renewal strategies for improving diffusion of building heat emission—A case in Xi’an, China

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Energy and Buildings

Pub Date : 2025-02-01 DOI: 10.1016/j.enbuild.2024.115160

Juejun Ge , Yupeng Wang , Ye Guo , Jicheng Wang , Dian Zhou , Zhaolin Gu

Air conditioning systems transfer heat from indoors to the outdoors during hot summers, exaggerating the urban heat island (UHI) phenomenon and the risks of relevant climatic disasters. Urban form renewal strategies are urgently required to improve the diffusion of building heat emissions (BHEs). In this study, the impacts of BHEs on the outdoor airflow and air temperature fields of 42 typical urban blocks in Xi’an were simulated using scSTREAM program. BHEs increased the near-surface UHI intensities by 1.0 °C and 1.4 °C in residential and mixed-use blocks, respectively. The diffusion conditions of the BHEs were better for blocks with lower building densities. However, the UHI increase caused by the BHEs was positively correlated with the floor area ratio only in the mixed-use blocks. Regression formulas describing the relationships between the UHI increase caused by the BHEs and block-form indicators were then proposed. In a district renewal project for urban climate optimization, these formulas were used as the fitness functions of genetic algorithm to determine the form indicators for all blocks therein. The district UHI intensity caused by BHEs could be reduced by 0.3 °C with the maintaining of the district development intensity.

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引用次数: 0

Impacts of HVAC cleaning on energy consumption and supply airflow: A multi-climate evaluation

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Energy and Buildings

Pub Date : 2025-02-01 DOI: 10.1016/j.enbuild.2024.115147

Nasim Ildiri , Emma Biesiada , Tullio Facchinetti , Norma Anglani , Nouman Ahmed , Mark Hernandez

Energy-efficiency interventions are crucial for sustainable building operations to accommodate emerging indoor air quality (IAQ) criteria into their engineering life cycles. While several studies have addressed building energy consumption and IAQ considerations separately, few provide integrated analysis of these aspects in response to building hygiene practices. In response, this study evaluates the effectiveness of routine heating, ventilation, and air conditioning (HVAC) cleaning on energy consumption and supply airflow patterns in non-residential public buildings. This study juxtaposes HVAC energy consumption and ventilation performance before, during and after routine HVAC cleaning, across buildings situated in four different climate zones, while operating in cooling mode. Each site had nearly identical HVAC systems serving similar architectural features and occupational loads; these were segregated into an intervention (cleaned HVAC system) that could be compared to an otherwise identically operating HVAC (control system), which was not cleaned. Following prescriptive cleaning, HVAC systems exhibited significant energy consumption reductions and delivered higher airflows compared to their uncleaned counterparts. On average, intervention systems saved between 41 % and 60 % on conveyance (fan/blower) energy, with one exception, and supplied 10 % and 46 % more airflow compared to their uncleaned counterparts. This research demonstrates how a new generation of low-cost HVAC system monitors can compile Internet of Things (IoT) archives to show immediate energy consumption benefits associated with cleaning HVAC components and their associated ductwork serving relatively high occupancy commercial and educational spaces.

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引用次数: 0

Impact of karst groundwater seepage on heat transfer efficiency of geothermal heat exchangers

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Energy and Buildings

Pub Date : 2025-02-01 DOI: 10.1016/j.enbuild.2024.115146

Yunshan Xu , Jiangtao Tao , Zilong Xiao

In karst regions, groundwater flows through complex conduits and fractures, resulting in substantial variations in flow velocity and temperature, which impact the efficiency of ground heat exchangers (GHEs). In this study, numerous model experiments were carried out to examine the temperature distribution of the stratum surrounding GHEs under karst groundwater seepage conditions. A 3D numerical model and experimental platform were developed to simulate the interaction between seepage and GHE thermal dynamics under varying seepage velocity, seepage temperature and operating modes. Model experiment results show that increasing seepage velocity significantly enhances heat transfer efficiency and mitigates thermal accumulation. The influence of karst groundwater seepage results in significantly less temperature fluctuation upstream compared to downstream. As seepage velocity increases from 3.59 × 10⁻⁶ m/s to 1.08 × 10⁻⁵ m/s, the temperature differential between upstream and downstream regions rises by 73 %, while the heat transfer efficiency of U-shaped pipes improves by 36.7 %. Variations in seepage temperature also play a pivotal role, with heat exchange efficiency increasing by 51.3 % as seepage temperature rises from 58.2 °C to 94.3 °C. The heat exchange capacity of GHEs and the temperature difference between downstream and upstream increase with the rising temperature of karst subsurface water seepage. The core impact of seepage temperature lies in how groundwater seepage initially alters the temperature field of the strata around the GHE, ultimately influencing the efficiency of heat exchange between the soil and the buried pipe. This research provides new insights for optimizing GHE systems and ensuring their long-term stability and energy efficiency in karst region.

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引用次数: 0

Effect of thermal-acoustic-air quality composite environments on overall comfort of urban pocket parks considering different landscape types

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Energy and Buildings

Pub Date : 2025-02-01 DOI: 10.1016/j.enbuild.2024.115167

Wenqiang Li , Li Tian , Xin Jin , Zaiyi Liao , Yao Tao , Pei Peng

To bridge the research gap of landscape types’ impact on overall comfort, this study studied the relationship between the combined effect of thermal-acoustic-air quality and overall comfort in urban pocket parks during winter through surveys and monitoring. Environmental parameters monitored included outdoor air temperature, relative humidity, wind velocity, ambient noise etc. The (thermal, acoustic, and air quality) comfort survey data, universal thermal climate index (UTCI), weighted equivalent continuous sound level (LAeq), and particulate matter with a diameter of less than 2.5 μm (PM2.5) were utilized to objectively evaluate the overall comfort vote (OCV). Furthermore, the comfort index-based and the perception vote-based OCV prediction models were built. Results showed that the water landscape parks had the highest overall and thermal comfort, followed by mountain, square, and building landscapes. For water and square landscape parks, the thermal comfort vote (TCV) was the most important comfort perception, while the air quality sensation vote (AQSV) was key for building landscape parks. No comfort perception vote index significantly affected OCV for mountain landscape parks. For “acceptable” OCV (=0), minimum UTCI thresholds were −5°C, −1.5 °C, and 5 °C for water, mountain, and building landscape parks, respectively, when LAeq exceeded 56 dBA, OCV remained constantly low (< 0) regardless of UTCI. The comfort index-based model is accurate and reliable for OCV prediction. This study provides the threshold requirements for achieving an “acceptable” overall comfort level in different types of pocket park, and could guide the urban pocket park design.

{"title":"Effect of thermal-acoustic-air quality composite environments on overall comfort of urban pocket parks considering different landscape types","authors":"Wenqiang Li , Li Tian , Xin Jin , Zaiyi Liao , Yao Tao , Pei Peng","doi":"10.1016/j.enbuild.2024.115167","DOIUrl":"10.1016/j.enbuild.2024.115167","url":null,"abstract":"<div><div>To bridge the research gap of landscape types’ impact on overall comfort, this study studied the relationship between the combined effect of thermal-acoustic-air quality and overall comfort in urban pocket parks during winter through surveys and monitoring. Environmental parameters monitored included outdoor air temperature, relative humidity, wind velocity, ambient noise etc. The (thermal, acoustic, and air quality) comfort survey data, universal thermal climate index (<em>UTCI</em>), weighted equivalent continuous sound level (<em>LAeq</em>), and particulate matter with a diameter of less than 2.5 μm (<em>PM2.5</em>) were utilized to objectively evaluate the overall comfort vote (<em>OCV</em>). Furthermore, the comfort index-based and the perception vote-based <em>OCV</em> prediction models were built. Results showed that the <em>wate</em>r landscape parks had the highest overall and thermal comfort, followed by <em>mountain</em>, <em>square</em>, and <em>building</em> landscapes. For <em>water</em> and <em>square</em> landscape parks, the thermal comfort vote (<em>TCV</em>) was the most important comfort perception, while the air quality sensation vote (<em>AQSV</em>) was key for <em>building</em> landscape parks. No comfort perception vote index significantly affected <em>OCV</em> for <em>mountain</em> landscape parks. For “acceptable” <em>OCV</em> (=0), minimum <em>UTCI</em> thresholds were −5°C, −1.5 °C, and 5 °C for <em>water</em>, <em>mountain</em>, and <em>building</em> landscape parks, respectively, when <em>LAeq</em> exceeded 56 dBA,<!--> <em>OCV</em> remained constantly low (< 0) regardless of <em>UTCI</em>. The comfort index-based model is accurate and reliable for <em>OCV</em> prediction. This study provides the threshold requirements for achieving an “acceptable” overall comfort level in different types of pocket park, and could guide the urban pocket park design.</div></div>","PeriodicalId":11641,"journal":{"name":"Energy and Buildings","volume":"328 ","pages":"Article 115167"},"PeriodicalIF":6.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143170901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermoelectric power generation in concrete: A study on influential material and structural factors 混凝土热电发电：影响材料和结构因素的研究

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Energy and Buildings

Pub Date : 2025-02-01 DOI: 10.1016/j.enbuild.2024.115159

Yong Luo, Hai Liu

This study presents an innovative design for a concrete-based energy harvesting system, focusing on ordinary concrete, steel fiber concrete, and bamboo fiber concrete to identify the most effective material for power generation and efficiency improvement. The temperature transfer characteristics and output voltage of each concrete type are examined in detail. Simulation analyses assess how ambient temperature, wind speed, and the embedding depth of conductive aluminum plates affect the system’s temperature field and output voltage. Field tests measuring the output voltage of steel fiber concrete confirm the model’s accuracy. Results show that steel fiber concrete achieves the highest output voltage, followed by ordinary and bamboo fiber concrete. Among influencing factors, ambient temperature has the most significant impact on output voltage, ranked as ambient temperature > wind speed > aluminum plate embedding depth. Over time, the influence of embedding depth on output voltage lessens. When the temperature difference across the thermoelectric module reaches 54.6 °C, the system generates an output voltage of 1.09 V, meeting low-power generation requirements. This research aims to reduce pavement temperatures, preventing damage to pavement structures from high temperatures, while harnessing the temperature difference between concrete pavement and air to generate clean energy. This approach meets the power demands of road systems and lays a solid foundation for integrating energy generation with construction.

本研究提出了一种基于混凝土的能量收集系统的创新设计，重点关注普通混凝土，钢纤维混凝土和竹纤维混凝土，以确定最有效的发电和效率提高材料。详细分析了各类型混凝土的温度传递特性和输出电压。仿真分析评估了环境温度、风速和导电铝板的嵌入深度对系统温度场和输出电压的影响。对钢纤维混凝土的输出电压进行了现场测试，验证了模型的准确性。结果表明，钢纤维混凝土的输出电压最高，普通纤维混凝土次之，竹纤维混凝土次之。在影响因素中，环境温度对输出电压的影响最为显著，排名为环境温度>；风速>；铝板埋深。随着时间的推移，埋设深度对输出电压的影响逐渐减小。当热电模块间温差达到54.6℃时，系统输出电压为1.09 V，满足小功率发电要求。这项研究旨在降低路面温度，防止高温对路面结构的破坏，同时利用混凝土路面和空气之间的温差来产生清洁能源。该方法满足了道路系统的电力需求，为实现产建一体化奠定了坚实的基础。

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引用次数: 0

Impact analysis of uncertainty in thermal resistor-capacitor models on model predictive control performance 热电阻-电容模型的不确定性对模型预测控制性能的影响分析

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Energy and Buildings

Pub Date : 2025-02-01 DOI: 10.1016/j.enbuild.2024.115112

Dan Wang , Wanfu Zheng , Siqi Li , Yixing Chen , Xiaorui Lin , Zhe Wang

Model Predictive Control (MPC) is extensively utilized for optimal control in building systems. Despite substantial research being dedicated to exploring the impact of uncertainties in external and internal disturbances on the performance of MPC, the existing studies neglect the potential impact of uncertainties in model parameter identification on control performance. To address this gap, this study quantifies the impact of model uncertainty on MPC performance through a test case in a virtual environment. Various levels of uncertainties for parameters R and C are artificially introduced to assess the MPC performance. The causes of the impact of model uncertainty on control performance are further explored through analysis. We select a first-order RC model to modelling building thermal dynamics. MPC is employed to optimize the heat pump signal with the goal of minimizing the energy cost while maintaining thermal comfort. The simulation results demonstrate that a negative deviation in model parameter identification has a more pronounced impact on MPC performance than a positive deviation, which has a negligible effect on MPC control performance. Deviations in parameters from their true values affect both heat losses from the zone and thermal capacity, thereby influencing the estimated temperature by the RC model. Consequently, these factors, in turn, affect the system’s control decisions, leading to variations in the objective function values. This study can provide an insight into the relationship of model parameters uncertainties and MPC performance, and facilitate the practical application of MPC in buildings.

模型预测控制（MPC）广泛应用于建筑系统的最优控制。尽管大量的研究致力于探索外部和内部扰动的不确定性对MPC性能的影响，但现有的研究忽略了模型参数识别中的不确定性对控制性能的潜在影响。为了解决这一差距，本研究通过虚拟环境中的测试用例量化了模型不确定性对MPC性能的影响。人为地引入了参数R和C的不同程度的不确定性来评估MPC的性能。通过分析，进一步探讨了模型不确定性对控制性能影响的原因。我们选择一阶RC模型来模拟建筑热动力学。采用MPC对热泵信号进行优化，在保证热舒适的同时使能源成本最小化。仿真结果表明，模型参数识别中的负偏差对MPC性能的影响比正偏差更显著，而正偏差对MPC控制性能的影响可以忽略不计。参数偏离其真实值会影响区域的热损失和热容量，从而影响RC模型估计的温度。因此，这些因素反过来影响系统的控制决策，导致目标函数值的变化。该研究有助于深入了解模型参数不确定性与MPC性能之间的关系，为MPC在建筑中的实际应用提供参考。

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引用次数: 0