Search

• Climate change and urban setting impact energy use of buildings. • Energy use is higher due to overlapping effect of climate change and microclimate. • A method is proposed to account for future and urban environment in thermal simulation. • The results can assist in sizing passive ventilation systems. Urban settings and climate change both impact on energy use and thermal comfort inside buildings. This paper first presents a study of changes in energy demand in residential buildings considering the overlapping effect of climate change and urban heat island intensity in two European locations; Cadiz (Spain) and London (United Kingdom), representing temperate and hot European climates and moderate and dense urban settings. Future-urban weather files were generated and simulations were run considering energy demand and indoor thermal comfort. In hot climate regions such as the one of Cadiz, future climate will increase the cooling demand and the additional impact of the UHI leads to a further increase of up to +28% of total energy demand compared to the current climate without considering urban effects. Future-urban weather conditions will be detrimental also for buildings in London, where the annual energy demand is predicted to increase by up to the 16% if future climate and urban effects are included. This is due to a higher increase in cooling demand compared to the reduction for the heating need. The paper also presents a method to take into account microclimatic conditions in naturally ventilated buildings, especially the effect of wind variations around the building which impacts natural ventilation rates. Air and surface temperature and wind speeds were studied using ENVImet and the resulting microclimatic conditions were used as inputs to the EnergyPlus Airflow Network model for the calculation of the building ventilation rates. It was found that ventilation rates are reduced (in comparison to meteorological weather files) and this reduction impacts negatively on internal operative temperatures. A thermal comfort analysis was carried out indicating that the selection of a suitable weather file and microclimatic conditions is essential for more accurate predictions of internal thermal comfort and will assist in the sizing of passive and active systems to avoid overheating. [ABSTRACT FROM AUTHOR]

• Overheating regulations and calculation methods in 26 European countries were compared. • Most of the existing calculation methods are outdated and do not fit climate-proof buildings. • France requires a mixed-mode operation of naturally ventilated households. • The UK developed a heatwave-based calculation approach. • Comfort-based, multi-zonal, and time-integrated calculation approaches are needed. With the ongoing significance of overheating calculations in the residential building sector, building codes such as the European Energy Performance of Building Directive (EPBD) are essential for harmonizing the indicators and performance thresholds. This paper investigates Europe's overheating calculation methods, indicators, and thresholds and evaluates their ability to address climate change and heat events. e study aims to identify the suitability of existing overheating calculation methods and propose recommendations for the EPBD. The study results provide a cross-sectional overview of twenty-six European countries. The most influential overheating calculation criteria are listed the best approaches are ranked. The paper provides a thorough comparative assessment and recommendations to align current calculations with climate-sensitive metrics. The results suggest a framework and key performance indicators that are comfort-based, multi-zonal, and time-integrated to calculate overheating and modify the EU's next building energy efficiency regulations. The results can help policymakers and building professionals to develop the next overheating calculation framework and approach for the future development of climate-proof and resilient residential buildings. [ABSTRACT FROM AUTHOR]

The growing awareness of climate change is constantly moving the attention of designers and policymakers from typical and current scenarios to future layouts. This new approach introduces a degree of uncertainty that should be accounted in the building design process. The multitude of possible scenarios suggests considering dynamic system that can adapt themselves to unpredicted operating conditions. The aim of this study is to test a new approach and a new flexibility metric analysing the behaviour of a high-performance dynamic internal curtain in current and future scenarios. The first part of the paper focuses on the optimization of the dynamic system in the current scenario; this preliminary analysis represents the traditional design approach and is considered the baseline for all the comparisons. Hence, defining a matrix of likely scenarios, this paper explores the behaviour of three different selected control strategies – always off (i.e., no curtain), fixed control, optimized control – in the different scenarios considering possible variations of i) climate, ii) urban context, iii) internal loads, and iv) building use. The main outcomes of the research are, on the one hand, the comparisons of the control strategies and the benefits of the dynamic system and, on the other hand, the definition of a new metric that can properly describe the flexibility of the building systems with reference to the future scenarios analysed. This metric is based on six classes – which describe the statistical distribution of the energy consumptions of all the scenarios simulated in the matrix – and an index called Energy Flexibility Index (EFI) that quantifies the flexibility of the technology considered. The case study analysed highlights how implementing a dynamic shading system, considering the same building use, can increase the EFI of nearly 21% for non-optimized control strategy and up to 23% when optimized. While changing the building use in residential reduces these values respectively, to 6% and 7%. [ABSTRACT FROM AUTHOR]

• Climate change's impact on retrofitting was tested on Le Corbusier's apartment. • Climate change scenarios project up to 70% increase in summer overheating. • Adaptive natural ventilation can reduce warm discomfort of 50–60%. • Adaptive setpoints can reduce total energy consumption of 20–30%. • Adaptive strategies are particularly favourable in historic buildings. Historic buildings, often exempt from retrofits to preserve originality, require retrofitting due to potential future climate-related indoor issues. For Modern Architecture constructions, there is a need to find solutions that help address the discomfort and heat losses caused by the extensive use of glazing. By analysing Le Corbusier's studio-apartment this paper aims to inspect: (i) Solutions for energy, Indoor Environmental Quality, and preservation; (ii) Climate change impact on them; (iii) Possible adaptation strategies to cope with climate change. Spectrally selective glazing reduced summer overheating by 15%; high-performance glazing lowers cold discomfort (24%) and heating (22%) but increased warm discomfort; shadings maintained energy use and reduced summer discomfort by up to 44%; thermal insulation can reduce winter discomfort and halves energy use but raised summer discomfort by up to 41%. Tests on 2050–2100 climate change scenarios reveal up to 70% more warm discomfort hours. Adaptive strategies can help, with natural ventilation cutting warm discomfort by 50–60%, and adaptive setpoints reducing cooling demand by about 35%. Adaptive strategies can complement traditional retrofitting in addressing current and future climate conditions, especially in historic buildings that require minimal interventions to preserve their historical characteristics and enhance resilience. [ABSTRACT FROM AUTHOR]

• Globally, population weighting substantially changes degree-days rate of change. • Choice of base temperature strongly influences degree-day calculation. • For typical base temperatures, heating degree-days are falling at twice the rate that cooling degree days are increasing. • Within countries, heterogeneity in population changes determines relative changes in heating and cooling degree-days. Anthropogenic greenhouse gas emissions are driving global increases in temperature. This rise will likely lead to an increase in demand for cooling in the coming years. However, increasing temperatures are not the main explanatory factor for why the world is moving towards more cooling. This paper compares population and area-weighted cooling and heating degree-days derived using ERA5-Land reanalysis temperature, to show that population growth in warmer parts of the world drives cooling demand globally. The analysis shows that mean global area-weighted heating degree-days have fallen 8.46 °C days/year, whereas population-weighted heating degree-days have fallen by 12.5 °C days/year. At the same time, mean global area-weighted cooling degree-days have risen by 3.0 °C days/year, while population-weighted cooling degree-days have risen at 6.0 °C days/year. By using sub-country analysis, this paper shows that population-weighted degree-days can substantially differ from area-weighted degree-days. Finally, the findings highlight that the choice of heating and cooling degree-day base temperature is the most important parameter in the variability of degree-days and will need to be understood better in order to accurately account for future heating and cooling energy demand. [ABSTRACT FROM AUTHOR]

[Display omitted] • High resolution data from a Dutch net zero energy neighborhood is analysed. • Most buildings are positive energy, emit less carbon than they offset. • Large occupant differences in energy demand are visible across the households. • Occupant preferences and weather conditions greatly influence thermal energy demand. • Due to the high thermal efficiency, there is a high risk for summer overheating. Decarbonizing the building stock is a central component of global climate change mitigation efforts. In practice, this decarbonization can be achieved by a variety of different measures, including improvements in building energy efficiency, electrification of energy demand to reduce reliance on fossil fuels, and installation of distributed (renewable) generation in conjunction with flexible storage. However, these large-scale, often disruptive changes to the built environment also raise a number of concerns, such as loss of occupant comfort exacerbated by climate change, and introduction of additional stressors on the distribution grid. In this paper, we demonstrate several conclusions using detailed sub-hourly data of two years (2019–2020) collected from 40 homes in a recently refurbished net-zero energy neighborhood in the Netherlands. This paper shows that, in renovation projects like the case study, net-zero energy balances should be considered on a neighborhood, rather than building level to minimize worst case planning by accounting for occupant influences and seasonal effects. Furthermore, the energy flexibility and climate resilience in the buildings seems to be rather limited, as a result of energy efficiency improvements. While helpful in climate change mitigation efforts, the large seasonal differences in energy demand and generation imply that this evolution is perhaps sub-optimal from the grid perspective. The results illustrate that all homes in the study were net-zero energy over the two year period, sometimes net positive by up to a factor of three. This led to considerable excess generation especially during the summer months. In addition, it was found that indoor air temperature sensors in a number of buildings showed overheating beyond guideline thermal comfort temperature of 25°C, showing potential thermal comfort and heat stress for vulnerable occupants. These results motivate energy storage or modifications of the installed heat pumps to leverage summer excess generation while reducing the impact of summer heat waves. These findings should enable the Netherlands and other countries aiming to fully decarbonize the building stock formulate better, future-proof policies. [ABSTRACT FROM AUTHOR]

• Develop a multistep approach for hygrothermal assessment of a hybrid facade system; • Build climate files for hygrothermal simulations using hourly measured weather data; • Develop a user-independent code to find and fill the weather data gaps; • The hybrid facade system has an appropriate performance under normal conditions; This paper describes a multistep approach that allows the design and assessment a hybrid, timber-based, facade system that can withstand current real conditions without being prone to mould. This approach is aligned with today's drive for a more sustainable built environment. A typical office building with the hybrid system was simulated in a BES tool to obtain the indoor conditions in three selected locations in Norway. Historic measured weather data were used to build climate files, in accordance with ISO 15927-4 methodology. The global radiation was split using the DIRINT model, while a user-independent code was developed to find and fill the weather datasets gaps. A model was built using a one-dimensional HAM software for each facade section to assess its hygrothermal performance, whose studies are scarce in literature, and determine whether the system is appropriate for Nordic climate. This analysis included mould growth risk assessment, determining the variance of the transient U-values and the influence of the wood surface treatment on the drying capacity of the facade. The obtained energy consumptions are in accordance with the current Norwegian regulations. Under normal conditions, the system works properly. However, problems arise if a higher initial moisture content exists in the materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Transform office buildings towards whole-life minimum carbon. • Integrated optimisation of retrofitting plan and operating schedules. • 44%, 74% and 68% decline in whole-life costs, carbon and energy after retrofitting. • 4–51% saving in whole-life carbon emission compared to design optimisation strategy. • 10% saving in whole-life carbon emission compared to operating optimisation strategy. The state-of-the-art retrofitting strategies generally use either passive or active measures to reduce carbon emissions during its operating stage. The coordination among a range of passive and active energy devices is not considered while the concept of whole-life carbon emission minimisation is not introduced. To overcome these three research gaps and to transform existing office buildings toward minimum whole-life carbon emissions, an integrated passive and active retrofitting approach is proposed. Through two inter-related design optimisation and operating optimisation processes, the set of retrofitting options can be identified to achieve overall optimal economic, energy, and environmental performance. The first research gap, lack of simultaneous consideration of various active and passive retrofitting measures, is solved by the whole system simulation of a range of active and passive refurbishment measures. The second research gap, lack of coordination among a range of active energy devices, is solved by iteratively determining the optimal operating schedules of active energy devices with overall retrofitting plan at the design stage. The third research gap, lack of whole-life carbon emission minimisation, is solved by simultaneously minimising both embodied and operating carbon emissions. A real three-floor office building acquiring retrofitting is used to test the effectiveness of this integrated passive and active retrofitting approach. Compared to the building at its current status, there could be 44%, 74% and 68% reduction in lifelong costs, carbon emissions and energy usages if the proposed retrofitting strategy is adopted. Compared to retrofitting the building using the state-of-the-art "design optimisation only" strategy, the proposed retrofitting approach can reduce 5.36%-34.37% whole-life energy consumption and 4.31%-51.10% carbon emissions. Compared to retrofitting the building using the state-of-the-art "operating carbon emission only" strategy, there is 11.92%, 10.55%, and 10.48% reduction in whole-life cost, energy usage and carbon emissions, respectively. Therefore, this paper is innovative in an aspect that minimum whole-life carbon emissions can be reached through integrated design of passive and active retrofitting measures. It can provide building owners, energy engineers and decision-makers with insightful building retrofitting solutions to tackle the energy crisis and climate change problems. This proposed retrofitting approach can also be modified to provide guidance in designing new low-carbon buildings. [ABSTRACT FROM AUTHOR]

Rooftops Photovoltaic systems present a feasible choice to mitigate the adverse effects of electricity costs and climate crisis. Different parameters have been defined to analyse this type of systems from monitored data. However, they only focus on the matching capability between the load and AC generation profiles together with the utility grid usage. Therefore, they do not consider the performance of the PV generator and the rest of components of the photovoltaic system. Moreover, although IEC-61724 standard defines common criteria to assess the performance of photovoltaic systems, this standard does not consider calculated parameters and yields adapted to the idiosyncrasy of Rooftops Photovoltaic systems. Thus, in this paper it will be provided new calculated parameters and yields (i.e. a self-consumption yield and a to grid yield) and performance ratios (i.e. self-consumption Performance Ratio together with a to grid Performance Ratio) which combine self-consumption with system performance providing a proper analysis from monitored data. Moreover, they may facilitate comparisons between installations with different array power. These new parameters may not only help to ensure that design objectives have been achieved but they may better assess the potential of this technology which are key issues for the deployment of this type of facilities. [ABSTRACT FROM AUTHOR]

• Incidence of windows design on energy and visual comfort is studied under climate change. • The case study is an office building located in representative European climates. • Triple low-emissive windows, in oceanic and continental climates achieves energy saving of −35 %. • Double selective windows assures savings from −27 % to −57 % in the warm and oceanic climate. • The primary energy will increase until 27 % in for warn climates considering the 2080 scenario. The design of the glazed elements of the building envelope is a critical issue for both new and refurbished building when the effect of climate changes and expected overheating conditions are considered. Indeed, the windows affect the building energy balance and also the natural lighting that impacts both on visual comfort and illuminance consumptions. This paper develops a methodological approach for performing a parametric analysis aimed at quantifying the effects of different window's designs on the total primary energy and visual comfort of an office in the most representative European climatic zones. The considered parameters are: windows' orientation, window to wall ratio, glass and frame type and the installation of shading system. A new approach for evaluating the resilience of the optimal solution selected for the current climates is introduced by taking into account medium and long-term emissions scenarios. This analysis suggests that in the warm-summer humid continental climate, a double selective window may be resilient. Indeed, in the worst emission scenario, the achievable annual energy saving will be around −26 % if compared with a clear double window. Meanwhile it will be lower than −10 % if compared with the same optimal solution but simulated in the short-term emission scenario. For the humid subtropical climates and hot-summer Mediterranean climates, the scientific community should be focused the development of new solutions because also a dynamic system as the electrochromic one, is not able to guaranteed energy saving in the future scenario. Indeed, also the optimal configuration selected under the current conditions would be characterized by higher primary energy request (between 16 % and 27 %) under the future emissions scenarios. [ABSTRACT FROM AUTHOR]

• This paper determines the relationship between urban form and building energy use. • The surface-to-volume ratio and obstruction angle of buildings are important. • Consideration of the heating energy type and building use can yield reliable result. • The urban heat island effect exerts an impact on the electricity use in some months. • Correlation variation is caused by the building permit date. In the climate change era, urban geometry serves to ensure sustainability for urban planners since it notably affects building energy consumption. However, previous studies have mainly conducted experimental investigations under hypothetical conditions. Without empirical evidence, it is difficult to implement these findings under real conditions. This paper examined empirical data to determine the urban geometry effect on building energy consumption in a large, complicated urban area. Urban geometric parameters, including the surface-to-volume ratio, obstruction angle, and building orientation, were measured across Seoul, and their correlations with building energy use were analyzed. The results show that the surface-to-volume ratio and obstruction angle are important, despite the empirical data complexity. Additional data analysis indicates that the heating energy type and building use consideration yields more reliable correlation coefficient trends. The potential impacts of natural ventilation and the urban heat island (UHI) effect on building energy consumption were examined. The UHI effect, rather than shadows on buildings, predominantly impacts the building electricity use in August and September. The correlation variation caused by the building permit date was investigated. The results in this paper could help urban planners and designers develop blueprints to control urban geometry and establish relevant design guidelines. [ABSTRACT FROM AUTHOR]

• A innovative and efficient model was proposed for multi-lane highway. • The learning was collected a lot of existed pavement segments and built a large-scale highway network. • The LCA and LCCA was integrated to assess the sustainability of the M&R decision. • GDE3 performs well in selecting more cost-effective M&R optimization. A pavement maintenance and rehabilitation decision-making model plays a significant role in the sustainable development of highway networks. However, various maintenance and rehabilitation models lack the capacity to provide multi-objective maintenance decision-making strategies, which are solely concerned with reducing maintenance costs. This study aims to propose a multi-objective maintenance decision-making model, called the Pavement Maintenance-Generalized Differential Evolution 3 (called PM-GDE3), by integrating the pavement condition indices and the generalized differential evolution 3 (GDE3) method. Economic aspect, pavement sustainability, and environmental dimensions were considered in the proposed model to increase the flexibility of pavement management. In this study, the widely-used PAVER maintenance system,which represents a conventional M&R decision-making model and the PM-GDE3 model were applied to estimate the optimal maintenance and rehabilitation schedules for the highway networks, and the results from these models were compared. The results show that the maintenance strategy obtained from the PM-GDE3 model maintains the highway in an acceptable condition. In addition, it has been found that the PM-GDE3 model saves 30.9% of maintenance expenses, about 169 million CNY, 16.9% of carbon emissions, around 4,469 kt, and 11.6% of energy consumption, 2.8GJ, for as long as 30 service years compared to the PAVER model. The PM-GDE3 model outperforms the widely used PAVER maintenance system due to its capacity to propose the optimal solution by establishing a real-time simulation with numerous pavement conditions after maintenance application. This field is the first attempt to combine pavement performance prediction model, life cycle assessment method and life cycle cost assessment. The achievements of the paper are expected to combat the impending energy crisis and climate change impacts of pavement maintenance and rehabilitation. [ABSTRACT FROM AUTHOR]

• Analyzed residents' thermal demand characteristics under the global climate change. • A new thermal comfort evaluation model of traditional dwellings was established. • The new thermal neutral temperature and comfort range of residents were proposed. • Different measures to improve the old and new types of dwellings were put forward. Global climate change has led to increased differences in the indoor thermal environment of traditional dwellings and residents' thermal adaptability, but quantitative research in this area needs to be updated and improved. In this paper, taking the old and new types of traditional dwellings of Guangfu Ancient City in Hebei province, China as the example, we first investigated the current situation of indoor thermal environment and thermal comfort characteristics of residents by means of subjective questionnaire survey and objective data measurement. The measured data showed that the average indoor temperature of old-type traditional dwellings in winter was far lower than the thermal comfort range of human body, and it was also higher than the relevant standard in summer. Secondly, we established a new thermal comfort evaluation model of traditional dwellings and proposed a new thermal neutral temperature of residents: old-type traditional dwellings (18.1 °C in winter and 27.1 °C in summer), new-type traditional dwellings (19.8 °C in winter and 25.7 °C in summer). Although the measured data showed that the thermal environment quality of the old-type traditional dwellings was poor, the residents had strong thermal adaptability. Finally, we put forward the different living performance improvement strategies of old and new types of traditional dwellings: The old-type traditional dwellings should focus on strengthening the thermal performance of the envelope structure, while the new-type traditional dwellings should solve the problem of low indoor humidity in winter. This research improves the evaluation system of human thermal comfort of dwellings in cold region of China, and provides a good case reference. [ABSTRACT FROM AUTHOR]

• Genetic Algorithm (GA) based on Non-dominated Sorting Genetic Algorithm 2 (NSGA2) method is used for optimization. • Building optimization using passive design strategies can reduce final HVAC energy use 32% • Building optimization using passive design strategies can reduce time-integrated discomfort 46% • Overheating in nearly Zero Energy Buildings will be aggravated with continuation of global warming. • Building thermal comfort optimization does not ensure overheating mitigation during unprecedented events. It is expected that heatwaves will strike more frequently and with higher temperatures with the continuation of global warming. More extreme heatwaves concurrent with disruptions in the cooling system can lead to significant overheating problems in buildings affecting occupants' health, productivity, and comfort. This paper projects current and future heatwaves on an optimized nearly Zero-Energy terraced dwelling in Brussels, assuming the outage of the cooling system. Initially, a multi-objective optimization is performed considering 13 passive design strategies using the Genetic Algorithm (GA) based on the Non-dominated Sorting Genetic Algorithm 2 (NSGA-II) method. It is found that high ventilation rate, low infiltration rate, high insulation, high thermal mass, integration of green roof, and application of operable roller blinds are beneficial in reducing the final HVAC energy use up to 32% and enhancing thermal comfort up to 46%. Subsequently, three optimal solutions are selected and analyzed under the highest maximal temperature heatwaves detected during the 2001–2020, 2041–2060, and 2081–2100 periods. It is found that non of the optimal solutions are able to fully suppress overheating during heatwaves and the cooling system outage. The indoor operative temperatures reach more than 29 ° C , which can cause serious health issues for the occupants. The situation will be exacerbated in the future since an increase in maximum Heat Index (HI) between 0.28 °C and 0.49 °C, an increase in the maximum operative temperature between 1.34 ° C and 2.33 ° C , and a decrease in Thermal Autonomy (TA) between 17% and 28% are estimated. Finally, some recommendations are provided for practice and future research. [ABSTRACT FROM AUTHOR]

[Display omitted] • UHMA research are booming in publications, authors, institutions, and research areas. • UHMA has evolved into a transdisciplinary research field, covering many emerging areas, beyond the built environments. • UHMA research covers: (i) UHI impact assessment and cause identification, (ii) microclimate regulation and human thermal comfort, (iii) climate-related health impact and adaptation, and (iv) urban heat mitigation strategies and techniques. • This study highlights UHMA knowledge gaps in seven dimensions and UHMA development in five aspects. • This study proposes 13 suggestions for promoting the transformation from UHMA research to practice. This paper presents a bibliometric review of the history and evolution of Urban Heat Mitigation and Adaptation (UHMA) from 1989 to 2021 to identify its research progress, knowledge gaps, and future research directions. The results indicate that research on UHMA is booming and that the field has diversified over time. Existing studies have examined UHMA from the environmental, technical, health, economic, and social perspectives. Over time, UHMA has evolved into a transdisciplinary research field, covering many emerging areas beyond built environments, including materials, computer sciences, physiology, chemistry, and geosciences. Relevant UHMA topics can be divided into four research clusters: (i) UHI impact assessment and cause identification, (ii) microclimate regulation and human thermal comfort, (iii) climate-related health impact and adaptation, and (iv) urban heat mitigation strategies and techniques. This study highlights some knowledge gaps in UHMA research, including (i) overfocusing on urban heat causes, effects, and mitigation solutions; (ii) more focus on mitigation, overshadowing adaptation, and preparation; (iii) highlighting materials and vegetation, but overlooking water features and urban form; (iv) incomplete understanding of heat-related impacts; (v) focusing more on microclimate and heat islands rather than extreme heat; (vi) unsound policy, social, and economic support; and (vii) lack of actual UHMA implementation. There are also some challenges in UHMA development, including (i) the uneven distribution of publications, authors, and affiliations; (ii) topic, affiliation, and nation aggregation and bias; (iii) slow evolution in key disciplines, publications, and authors; (iv) knowledge isolation owing to tendentious academic collaboration and communication; and (v) limited journal scope and restricted methodological approaches. To overcome such challenges and enhance UHMA research and policy, 13 suggestions were made. Overall, by promoting transdisciplinary UHMA research informed by climatic sciences, scientific models, policy-relevant techniques, and socio-economic support, this study is expected to better frame UHMA research and bridge science and policy. [ABSTRACT FROM AUTHOR]

• Investigated climate change impacts on office building performance in Brussels. • Applied a long-term climate change sensitive system sizing and design approach. • Time-integrated discomfort analysis showed a major surge in overheating by 2100. • Long-term climate change resistivity is ensured in reference building until 2100. • Primary energy use and GHG emission findings are useful in mixed humid climates. As climate change continues, it is expected that the risk of overheating will rise in both new and existing buildings in mixed humid climate zones in Europe. This study introduced a novel climate change sensitive sizing and design approach for cooling and heating systems in nearly zero-energy office buildings in Brussels, Belgium, for different weather scenarios. This approach considered the long-term effects of climate change on building performance. The climate change effects were assessed using current and future climate data from the regional atmospheric model, MAR. To demonstrate the approach, a case study of a nearly zero-energy office building in Brussels was conducted. The reference building model was first calibrated using monthly energy use data from the year 2019 using ASHRAE Guideline 14. Then, the building was evaluated with different HVAC strategies and their performances were quantified. The results indicated an increase in overheating as high as 1.2 °C and cooling energy use as high as 13.5 kWh/m2 and a decrease in overcooling as low as 0.3 °C and heating energy use as low as 10.9 kWh/m2 in the reference building by the end of the century. In addition, due to climate change sensitive sizing and design approach coupled with optimal sizing, the reference building was climate change resistant towards the worst-case scenario by end of the century with up to 3.7 for climate change overheating resistivity and 20.2 for climate change overcooling resistivity. Finally, the paper provided recommendations for future practice and research based on the study findings. [ABSTRACT FROM AUTHOR]

Climate change is increasing heatwaves occurrence, which consequently impact buildings indoor overheating during summers. While indoor overheating in free-running buildings during future typical summers has been quantified by many researchers, its intensification during future heatwaves remains relatively under-researched. Furthermore, analyzing the dynamic thermal response of free-running buildings to these varying local climate changes is current lacking. This paper objective and novelty is to understand the building dynamic thermal change during different indoor overheating periods induced by several hot outdoor sequences during present and future climates. Two sensitivity analysis methods are used for this analysis, applied to a free-running top floor apartment of a collective building: the Morris method, which allows to quickly select the most influential parameters and the Sobol method, which allows to conduct an in-depth temporal uncertainty and sensitivity analysis. Results show that in the semi-oceanic climate of the French capital Paris, while the indoor overheating is projected to drastically increase, the building dynamic thermal behavior is greatly modified amongst the three climate sequences under study: present and future typical summers, and future heatwave of the mid-century. During the future heatwave in Paris, the building response is projected to behave more similarly as it would in a French Mediterranean city. Static design parameters such as thermal mass, albedo and emissivity or glazing percentage, as well as dynamic design parameters such as the operation of the ventilative cooling and solar control strategies all play an important role in regulating the building indoor overheating, with a different ranking depending on the outdoor local climate conditions. These results are of foremost importance to provide guidance in the design of adapted buildings to climate change, which can withstand future extreme heat periods. [ABSTRACT FROM AUTHOR]

Strict energy performance requirements have reduced the building's operational energy use and related environmental impact in the past decades. Consequently, the embodied impacts of buildings gained importance, and hence focussing on the life cycle impacts has become essential to further reduce the environmental impact of buildings. Life cycle assessment (LCA) is an internationally accepted method used for this purpose. Current LCA studies of buildings typically look at their whole life cycle but ignore potential changes in operational energy use due to climate change. However, the latter is expected to influence the operational energy use of buildings to a significant extent. This paper aims to improve the assessment of the operational phase by including variations in the yearly operational energy use caused by climate change and expected changes in the electricity mix as a strategy for climate change mitigation. This adapted dynamic assessment method is used to assess a Belgian office building. The results indicate that a Representative Concentration Pathway (RCP) 8.5 climate change scenario causes a decrease of 18 % for the end use of gas for heating and an increase of 32.4 % for the electricity use for cooling and ventilation. For the case study, the reduction of the environmental impact due to the decrease in gas use compensates the impact increase due to the higher electricity use. An increase in environmental impact in future would however occur if both heating and cooling are provided by electricity. Furthermore, depending on the changes that will occur in the electricity mix, the global warming potential of the office building will change by −13 % for an electricity mix dominated by renewables and by + 10 % for one with mainly production by gas compared to the situation with the current mix. However, the inclusion of a more extended list of environmental indicators shows that the overall environmental impact will only reduce by 4 % or even increase by 7 % compared to the situation with the current mix. [ABSTRACT FROM AUTHOR]

Despite the remarkable contribution of urbanisation to socio-economic development, it has complicated negative impacts on the environment. The growth of urbanisation has noticeable adverse impacts on urban microclimate and parameters generating the urban heat island (UHI) effect. These impacts, exacerbated by the gradual influences of global warming over time, make urban microclimate changes more complex. The future urban development and climate change adaptation plans in New Zealand (NZ) show almost no evidence of considering the status of future urban microclimate, UHI and outdoor thermal comfort. An initial literature review showed a relatively small number of papers and grey literature on urban microclimate in NZ. This motivated the authors to explore the status of studies on the urban microclimate and the following impacts on UHI and outdoor thermal comfort in NZ. The results showed a relatively small body of knowledge on urban microclimate studies in research articles published and governmental reports in the context of NZ. Likewise, the inconsistency of research parameters and methods studied and the lack of validation in the available studies, plus the neglection of future urban development and urban morphology, limit the clarity of the scientific understanding of changes to the urban microclimate in NZ. The results of this study address the missing links and provide new insight for future studies. This study suggests providing models that consider the continuous changes to the urban microclimate considering the uncertainty of climate change impacts on weather factors such as temperature and airflow. Assessment of the impact of current and future urban morphology on UHI is necessary to develop optimised urban design guidance. [ABSTRACT FROM AUTHOR]

A rapidly warming planet provides a significant challenge to the design, delivery, and maintenance of habitable housing across Australia. Information on the adequacy of current measures for cooling Indigenous houses in regional and remote communities in relation to climate change and rising energy consumption costs is lacking. Such information is needed to better protect low socio-economic status householders, people with pre-existing health conditions, and people living in climatically exposed regions. This article models the thermal performance of both existing and 'improved' (built to current national construction code standards) housing stock in relation to various occupancy density, cooling system, and ventilation practice scenarios. This modelling was undertaken for housing in Australia's tropical, arid, and hot/mild climate zones, matching the sites where most discrete Indigenous communities are located. Results show that retrofitting existing housing stock and even building new stock to meet recommended standards are not adequate measures for current or future climate changes. This paper challenges current knowledge, policy, and practices regarding Indigenous housing, demonstrating that significant reform is necessary to maintain habitable conditions and improve energy resilience. [ABSTRACT FROM AUTHOR]

[Display omitted] Many cities are facing urban heat problems, the combined effect of heatwaves under global climate change, and local warming associated with urbanization, resulting in severe environmental, economic, social, and health impacts. It is urgent to address urban heat problems. Buildings are an important cause of urban heat, while buildings are favorable spaces to deal with urban heat problems through built environment decarbonization and the implementation of cooling strategies. Green building (GB) which has been recognized as an innovative philosophy and practice in the building sector, is proposed to address urban heat challenges. However, existing studies have offered a limited understanding of GB-based urban heat mitigation and adaptation (UHMA). Therefore, this study aims to examine how GBs can contribute to UHMA. In particular, this study analyses the contribution of buildings to urban heat problems in aspects of carbon emissions and the extensive modifications towards artificial landscapes, and discusses the possible impacts caused by urban heat problems. Afterwards, this study develops the framework of GB's responses to urban heat in global warming mitigation, local warming mitigation, and urban heat adaptation. Based on this, such responses are analyzed in aspects of site planning, outdoor environments, transportation, building design, energy efficiency, water efficiency, material efficiency, indoor environmental quality, operation management, construction, and maintenance following the whole life cycle perspective. This paper helps understand how GB techniques contribute to UHMA and provides a reference to the revision of the GB assessment system for addressing urban heat problems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Archetype development, model components and potential applications for UBEM are discussed. • Stochastic and dynamic occupancy models are among the most desired improvements for UBEM. • UBEM could be suitable for high accuracy predictions of future climate change scenarios. • Integration of socio-economic data in UBEM is promising but not currently applied. • Assigning value year from renovation records is tempting but could entail several pitfalls. Due to rapid urbanisation and the significant contribution of cities to worldwide energy use and greenhouse gas emissions, urban energy system planning is growing more important. Urban building energy modelling (UBEM) draws increasing attention in the energy modelling field due to its inherent capacities for modelling entire cities or building stocks, and the potential of varying data inputs, approaches and applications. This review aims to identify best practices and improvements for UBEM applications by examining previous research, with a focus on the currently least established approaches. Different archetype development procedures are analysed for common problems, six main under-developed input approaches or parameters are identified, and applications for future scenario development are surveyed. By analysing previous studies in related fields, this paper provides an overview of gaps in the published research and possible additions to future UBEM projects that can help expanding the existing modelling procedures. Comprehensive human behaviour models with additional aspects beyond occupant presence are identified as a major point of interest. Further research on socio-economic parameters, such as household income and demographics, are also suggested to further improve modelling. This study also underlines the potential for utilising UBEM as a tool for evaluating future climate change scenarios. [ABSTRACT FROM AUTHOR]

• The resilience of a building designed to be nearly zero energy is evaluated in Mediterranean climate. • Weather file defined with monitored data are used for a short-term analysis. • Projections of climate changes are considered in the construction of weather files. • The net primary energy will decrease (–23%) and the in-situ renewable adoption will increase (85%). • Overheating will occur in the intermediate months with the need to turned on the cooling system. The paper is focused on the evaluation of how the climate changes can influence the performance of buildings designed to be nearly zero energy (nZEB) and on the evaluation of the resilience in term of energy balance. A real case study is used; it is named BNZEB, a single-storey dwelling built in Benevento (South Italy, Mediterranean climate). With five-years monitored meteorological data, both a short-term and medium-term analysis is developed; the first one consists in the evaluation of the energy behavior compared to the first operating year. Then, the energy performance is evaluated considering the medium-term climate projections generated using the CCWorldWeatherGen tool. This analysis, with reference to the case study, suggests to designers and researchers that, in a typical Mediterranean climate, the reduction of the heating demand could compensate the increment in the cooling request. In the worst climatic scenario, the net primary energy could change from 25.4 kWh/m2 year (first year of life, 2017) to 19.5 kWh/m2 year (projection to 2050) with a rate of self-consumption of 85% (80% for 2017). However, a critical point is the operating period of the cooling system. Indeed, an indoor overheating problem could occur during the spring with operative temperature higher than 30 °C; this indicates that in future, the occupants will require higher number of operating hours with most frequent switch off. This could change the results of the energy balance, reducing, for instance, the imbalance between production and consumption that currently occurs in the intermediate periods. [ABSTRACT FROM AUTHOR]

In the wake of growing concern for climate change, heat waves and their potential health effects (McGeehin and Mirabelli, 2001) [37] have become a recurring phenomenon (Beniston, 2004; Fouillet et al., 2006) [8,21]. Extreme heat events in the USA are responsible for more deaths as compared to other weather events such as hurricanes, lightning, tornadoes and floods (Luber and McGeehin, 2008) [33]. Heat exposure in buildings has risen due to global warming in conjunction with other factors like urbanization and associated heat island effects (Kolokotroni et al., 2012) [25] , lack of thermal mass (Lomas and Porritt, 2017a) [31] , exposure to solar insolation on higher stories, absence of window shading, overcrowding and envelope properties exacerbate the overheating inside the dwellings (Vellei et al., 2017). [45]. Stone et al. (2021) [43] provides a macro view of the indoor environments in buildings due to the concurrent event of power outage during heat wave in face of climate change. This paper builds on the previous publication and provides a detailed view of modeling methodology, building physics that explains the sources/sinks of heat and entails a detailed evaluation of the current building stock for the low to moderate income residences in the city of Phoenix, Arizona in terms of their thermal performance. Finite Element models of building stock were simulated using MATLAB for microclimate weather files of Phoenix generated by Weather Research and Forecasting (WRF) simulation. Significant differences in temperature were noted in same building archetypes in different pockets of the city indicating the role of urbanization in aggravating the impact of heat wave. Dwellings with high thermal mass are found to be much more resilient to high ambient temperatures as compared to code compliant residences with basements being the coolest zones in all prototypes. [ABSTRACT FROM AUTHOR]

[Display omitted] Dynamic modeling of building performance is essential for understanding how current buildings will respond to projected changes in environmental conditions, and how these responses will in turn affect building occupants. Additionally, expected shifts in background energy systems will change the carbon intensity of energy delivered to buildings, while shifts in atmospheric composition will alter the global warming potential of each greenhouse gas. This paper models these three dynamic systems simultaneously to determine which projected shifts will have the largest influence on global warming impacts and occupant satisfaction metrics throughout the use phase of an office building prototype model in different climate zones of the United States. The median of RCP8.5 and RCP4.5 climate scenarios were used to morph local weather files to simulate the electricity and natural gas needed to meet heating and cooling loads in each location, as well as thermal comfort and daylighting metrics. These RCPs were also used to estimate shifts in the global warming potential factors for CO 2 , CH 4 , and N 2 O. Projected shifts in the electricity generation mix and upgrades to transmissions and distribution infrastructure in each region were used to estimate future carbon intensity factors for building site energy use. Compared to the baseline results, decarbonization of the electricity grid results in the largest shift in building operational GHG emissions, far outweighing emissions increases due to higher cooling loads. Shifts in ambient temperatures and direct and diffuse radiation had heterogeneous effects on occupant comfort, particularly in Boston across different seasons and orientations. Understanding how building performance is expected to respond to complex future trends will assist in designing adaptive buildings that take advantage of projected changes. [ABSTRACT FROM AUTHOR]

• A comprehensive analysis of data from commercial buildings in United States to identify operational problems and opportunities. • These opportunities were not strongly correlated with building vintage, size, or building type, but were reflective of how the buildings are operated. • This analysis showed that opportunities to improve building operations exist in almost every building. • There was wide variation in whole building energy savings, ranging from 0 to 50% and 0 to 18 $/m2 with median percent annual whole building savings of 12% and median normalized annual cost savings of $1.75/m2. In the United States, as much as 30% of the 19 EJ that commercial buildings consume is considered excess. Much of the excess energy is due to the inability to manage building operations efficiently. Because almost 20% of the total primary energy consumption is associated with commercial buildings, significant energy reductions in this sector are needed to mitigate climate change. Therefore, many cities and states are mandating periodic "tune-ups" of these buildings to eliminate excess energy consumption. Although the benefits of tune-ups and retro -commissioning are clear, focusing these mandates to look for specific opportunities has been a challenge because of the lack of studies that document the prevalence of opportunities. Therefore, we analyzed building automation system data from 151 buildings across the United States to document common operational problems and opportunities to improve building operations. This analysis showed that opportunities to improve building operations exist in almost every building. These opportunities were not strongly correlated with building vintage or size, but were reflective of how the buildings are operated. The prevalence of the top 20 opportunities ranged between 74% and 23%, with 40% of these associated with air-handling units. The rest of the opportunities are associated with schedules, chilled and hot-water distribution, and zone controls. Of the 151 buildings, 69 of them implemented corrective actions of some or all opportunities that were identified. Implementation varied across the Re-tuning categories, with 60% for schedule opportunities, 50% for zone opportunities, over 40% for the air-handling unit and hot-water opportunities, and 35% of the chilled-water opportunities. There was wide variation in whole building energy savings, ranging from 0 to 50% and 0 to 18 $/m2 with median percent annual whole building savings of 12% and median normalized annual cost savings of $1.75/m2. In addition to documenting these key findings, the paper provides a list of opportunities that can be automatically and continuously identified and corrected and offers a list of those opportunities that should be the focus of the mandates. [ABSTRACT FROM AUTHOR]

• GAN is utilized to create synthetic building performance profiles. • Synthetic projections are conditioned based on climate and building operation. • Uncertainty is infused into synthetic data to create perturbed performance profiles. • Out-of-sample synthetic data is utilized to evaluate the performance of a RL Agent. This paper describes the process of creating uncertainty-infused synthetic profiles of building performance. The synthetic profiles are utilized as a resource for evaluating the response of trained machine learning models to unseen events. Applications of the introduced method can benefit researchers and practitioners who train data-driven building models on limited historical data and is particularly useful when a physics-based model of the building is unavailable. As an original contribution, we propose a conditional deep convolutional Generative Adversarial Network (GAN) for projecting multi-dimensional time-series profiles of building performance. The proposed GAN reflects climate and operation variations into the synthetic building performance profiles, while preserving the internal consistency within the generated data. To ensure high quality synthetic profiles, this study validates the plausibility of generated data through qualitative (visualization) and quantitative (Pearson correlation, Wasserstein distance) assessments. Synthetic profiles are fed to a trained reinforcement learning model and a rule-based controller to compare their performances in the presence of uncertainty. Results show that with limited training data, a reinforcement learning model's response can be fairly sensitive to uncertainties and disturbances, insofar, some advantages over rule-based controllers may be overestimated. To ensure the reproducibility of the presented results, this study is conducted on open data and models are shared as open source. [ABSTRACT FROM AUTHOR]

Through tests conducted at the Toronto and Region Conservation Authority's (TRCA) Archetype Sustainable Houses, a hybrid residential space heating system with a supervisory controller was monitored and studied to evaluate its performance and effectiveness for the heating season. A high efficiency natural gas furnace (NGF) and an electric air source heat pump (ASHP) were coupled together to meet the space heating demand of the house. This integrated system is called the cloud based Smart Dual Fuel Switching System (SDFSS) that considers time-of-use (TOU) pricing, fuel cost, short-term weather forecast, and equipment efficiencies and capacities. This multi-variable decision-making process defines an optimal schedule for the hybrid system to run more cost effectively. This paper analyses two separate SDFSSs. According to these analyses, the SDFSS systems showed lower operating cost with respect to the furnace or the ASHP system alone with various carbon tax (CT) levels from $0 to $250/tonne of CT with an increment of $10/tonne of CT that were simulated, along with a significant GHG emission reduction relative to the conventional heating systems. Furthermore, with these technologies, Canada's residential sector could potentially meet Canada's Paris Agreement goals. The SDFSS technology is a is flexible, user friendly, ubiquitous technology for the smooth transition from today's natural gas dominated space heating system to the future's low carbon infrastructure powered by a heat pump and renewable energy. [ABSTRACT FROM AUTHOR]

[Display omitted] • A comparative LCA of different vertical greenery system was performed. • Operational stage had the highest impact by up to 90% of the total impacts. • When excluding the operational stage, manufacturing is the most contributor. • In the green wall system fertilizers impact 71% of the total maintenance. • Green wall was not as sustainable as the green facade due to the support system. The building and construction sector is a large contributor to anthropogenic greenhouse gas emissions and consumes vast natural resources. Improvements in this sector are of fundamental importance for national and global targets to combat climate change. In this context, vertical greenery systems (VGS) in buildings have become popular in urban areas to restore green space in cities and be an adaptation strategy for challenges such as climate change. However, only a small amount of knowledge is available on the different VGS environmental impacts. This paper discusses a comparative life cycle assessment (LCA) between a building with green walls, a building with green facades and a reference building without any greenery system in the continental Mediterranean climate. This life cycle assessment is carried according to ISO 14040/44 using ReCiPe and GWP indicators. Moreover, this study fills this gap by thoroughly tracking and quantifying all impacts in all phases of the building life cycle related to the manufacturing and construction stage, maintenance, use stage (operational energy use experimentally tested), and final disposal. The adopted functional unit is the square meter of the facade. Results showed that the operational stage had the highest impact contributing by up to 90% of the total environmental impacts during its 50 years life cycle. Moreover, when considering VGS, there is an annual reduction of about 1% in the environmental burdens. However, in summer, the reduction is almost 50%. Finally, if the use stage is excluded, the manufacturing and the maintenance stage are the most significant contributors, especially in the green wall system. [ABSTRACT FROM AUTHOR]

• Economic drivers and barriers were identified to be most significant for ZCB in HK. • User behavior changes can have a major impact on ZCB delivery in HK. • Four strategy areas most address ZCB complexities and dynamics in high-density cities. • ZCB requires micro-level measures, meso -level initiatives and macro-level visions. • A novel multi-level framework of strategies is derived for high-rise high-density ZCB. The zero carbon building (ZCB) approach has been adopted in many cities and regions as an important government strategy for addressing climate change, achieving a low carbon economy, and uplifting the quality of people's life. However, there is yet a lack of uptake of ZCB in high-rise high-density contexts, and mystery exists about its feasibility and societal acceptance. This paper aims to demystify ZCB development in high-rise high-density cities by identifying and examining the drivers, barriers and strategies within Hong Kong as a typical case. Based on the systems theory that addresses ZCBs as complex systems, the research was conducted through a questionnaire survey with 219 effective responses from and six follow-up focus group meetings with industry stakeholders. Key drivers and barriers were systematically identified, covering economic, legislative, cultural, supply chain, geographical, and skill and knowledge aspects. Specifically, economic drivers and barriers were found most significant. A novel multi-level framework of strategies was further derived, integrating micro-level measures, meso -level initiatives and macro-level visions for achieving ZCBs in high-rise high-density cities. The framework contributes a new perspective to examine ZCB drivers and barriers, and lays the foundation for a strategic decision-making tool to support ZCB developments. [ABSTRACT FROM AUTHOR]