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• Indoor-quality oriented approach is proposed for building post-retrofit analysis. • The approach is based on readily monitored indoor data and on mangers and users' opinions. • As case study, the student dormitory of University of Athens is presented. • Thermal comfort indices greatly vary with management strategy and personal choices. • The analysis of indoor air quality highlights the key role of mechanical ventilation. The rapid expanding of refurbishment incentives requires to deserve more attention on how to reach nearly zero energy standard without compromising occupant wellness, when the building is undergone to important architectural transformations. To overcome the above drawbacks mainly for student dormitories, the paper introduces a new indoor quality oriented post-retrofit evaluation approach that simultaneously quantifies the impact of design decisions on thermal, respiratory and visual comfort. Investigations on the building quality and readily monitored indoor variables are the core of the approach that also provides sensitivity analysis on some subjective parameters and questionnaires for the main involved stakeholders. The proposed approach is tested on a student dormitory belonging at National and Kapodistrian University of Athens, refurbished in the frame of Horizon Project Pro-GET-OnE. The results reveal an improvement in the passive control of thermo-hygrometric comfort as well as in the satisfaction level. The adoption of mechanical ventilation consistently ensures dioxide emissions lower than 430 ppm, TVOC below 300 μg/m3 and PM2.5 and PM10 lower than 6 μg/m3. More in general, it is remarkable the importance of considering all comfort domains and occupant behavior, as one design or management choice might improve one indoor quality domain at the cost of others. [ABSTRACT FROM AUTHOR]

The impact of data characteristics on dataset quality is of significant guidance in the field of thermal comfort field surveys. In this paper, a Chinese thermal comfort database has been established, comprising quality-controlled on-site survey data. The database encompasses 41,977 sets of on-site survey data collected from 50 cities across 24 provinces, spanning a period of nearly 20 years from 2001 to 2021. It includes the five thermal zones in China and encompasses three seasons—summer, transitional, and winter—as well as four types of buildings: office buildings, residential buildings, student dormitories, and classrooms. The database exhibits an extensive data distribution, demonstrating a certain level of representativeness in terms of environmental temperature and survey locations. Based on this established database, the thermal sensation model was employed as the criterion for evaluating dataset quality. This study analyzed the impact of data characteristics on dataset qualityfrom three perspectives: sample size, data distribution, and data range. A sample size calculation method using interval estimation was adopted, determiningthat a minimum sample size of 350 is required for on-site thermal comfort surveys in office and residential buildings. A comparison revealed that compared to data with the normal distribution and uniform distribution, data with the positively skewed distribution exhibit lower neutral temperatures, while data with the negatively skewed distribution exhibit higher neutral temperatures. The thermal sensation model constructed based on data with uniform distribution demonstrates greater robustness. As the temperature range decreases, the neutral temperature increases in winter and decreases in summer, resulting in reduced accuracy of the constructed thermal sensation model. [ABSTRACT FROM AUTHOR]

This paper presents a novel radiant heating system with a wall-embedded micro heat pump (WEMHP) for residential buildings. The interior surface temperature of the exterior wall-section empowered by the micro heat pump is independently controlled, enabling distributed thermal comfort delivery. The micro heat pump consists of a miniature compressor along with an aluminum roll-bond condenser and evaporator. In contrast to conventional hydronic radiant systems and heat pumps with separate indoor and outdoor units (i.e., split systems), the WEMHP is a "packaged" system that would not require on-site installation and charging of a secondary water loop and circulation pump or refrigerant piping. This could ultimately lead to reduced installation and maintenance costs. In this study, a detailed system model is presented and integrated with a single-zone building model to assess the energy performance of the WEMHP in heating mode. For a designed living room scenario with an external wall WEMHP-to-wall ratio (HPWR) of 0.6 and window-to-wall ratio (WWR) of 0.2, the simulation results show that up to 23 % energy savings compared with a baseline air-to-air heat pump are possible. The results also indicate the HPWR needs to be higher than 0.4 to achieve performance comparable to the baseline. Additionally, experiments were conducted in a laboratory environment in which surface temperatures were controlled to emulate different scenarios for integration of WEMHP technology and to evaluate thermal comfort conditions. The experimental results show that the median operative temperature differences in the indoor environment were within 0.5 °C for various locations while the largest radiant asymmetry was 2.2 °C for the designed room configuration. Moreover, simulations were conducted to evaluate thermal comfort conditions in applications having a smaller HPWR of 0.4 with various values of WWR. Overall, the combined simulation and experimental study shows that the WEMHP has potential to reduce energy use while maintaining thermal comfort at acceptable levels where the HPWR is higher than 0.4. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two modules were analyzed during Antarctic summer at Spanish research station. • Measured transmittances and infiltrations were excessively high, resulting in high energy consumption for heating. • Indoor air conditions were poor in both modules, particularly the CO 2 concentration. • Extreme weather conditions accelerated the degradation of insulating materials and sealants. • Energy efficiency standards are urgently needed to improve the carbon footprint of Antarctic bases. In this paper, we present the energy characterization of two habitable modules at the Spanish station "Gabriel de Castilla", located on Deception Island, Antarctica. The analysis includes profiles of energy consumption for space heating and domestic hot water, as well as indoor air conditions, which were all recorded during one month of Antarctic summer. Additionally, the measurement of walls' transmittance and air infiltrations, together with thermography analysis, enabled evaluating the conservation state of the buildings' envelope. Upon analyzing all this data, it is evident that there is potential to enhance the design of future modules, improving the thermal comfort while significantly reducing the energy consumption. This will contribute to decrease the logistics and environmental impacts of these research stations, crucial considerations in human activity on the Antarctic continent. [ABSTRACT FROM AUTHOR]

[Display omitted] • Localized heating systems are a proper solution for providing thermal comfort. • Providing personalized heating by radiation or conduction is more convenient, so the inhaled air is kept cool and pleasant. • Local radiant heating systems directly heat the body without heating the environment, leading to lower energy consumption. • With local radiant heating systems, proper thermal comfort and sensation can be achieved even at low air temperatures. Localized heating systems are a proper solution for providing thermal comfort while lowering energy consumption in cold environments. Local radiant heating systems provide thermal comfort at lower air temperatures than convective systems which heats air, resulting in cool and pleasant inhalation air. This paper reviews experimental studies regarding local radiant heating systems considering thermal sensation and comfort. These systems can heat body directly, often with a big view factor toward the body. They do not necessarily heat the air and environment, leading to lower energy consumption. Other types of heating systems combined with local radiant heating systems are also reviewed in this paper. According to reviewed studies, localized methods improved thermal comfort, and the same thermal sensation could be achieved in lower air temperatures, especially when using local radiant heating systems. To design local radiant heating systems properly, improvement of existing local thermal comfort and sensation modeling based on radiant heat transfer is needed. [ABSTRACT FROM AUTHOR]

The optimization of HVAC system control affects the thermal comfort of building environment and air-conditioning energy consumption. However, most existing studies concentrate on human thermal comfort and neglects to incorporate air-conditioning energy consumption required to establish a controlled indoor thermal environment within the policy, which results in air-conditioning system high energy consumption. This paper suggests an indoor temperature intelligent control method based on thermal comfort and energy consumption of air-conditioning, and the TD3 algorithm is employed as an intelligent control algorithm to obtain the optimal setpoint that maximizes the joint benefit of the occupant's thermal comfort and the energy saving rate of air-conditioning system. The air-conditioning indoor temperature intelligent control model based on TD3 algorithm is trained by using the experimental data, and the method is simulated in TRNSYS simulation software to corroborate the efficacy and energy saving rate of the method. The results indicate that the indoor temperature intelligent control model based on thermal comfort and energy consumption of air-conditioning has less optimal adjustment of indoor temperature setpoints, which is more stable for the air-conditioning system and can satisfy the thermal comfort demand at the initial control stage to prevent significant fluctuations in human thermal sensation compared to the linear control method based on thermal sensation and the fuzzy control method based on thermal sensation. Besides, the average daily energy consumption can be reduced by 6.54% and 3.37% respectively, when compared to the linear control method based on thermal sensation and the fuzzy control method based on thermal sensation. [ABSTRACT FROM AUTHOR]

• Oil fume control, thermal comfort and energy of commercial kitchen are explored. • Demand exhaust rate of fume hood is determined on oil control effect. • Conditioned air supply parameters are determined on thermal comfort. • On-demand ventilation reduces ventilation and air conditioning energy by 71.16%. • Airflow optimization reduces airflow by 20% and energy by 50.81%. To analyze the energy-saving potential of commercial kitchen ventilation and air-conditioning (VAC) systems and to create a good kitchen environment, this paper calculates the key influential parameters of the exhaust air volume and air supply temperature through CFD simulation. The former depends on the fume control effect and is closely related to the make-up air method, while the latter is governed by the thermal comfort. The energy consumption under different operational strategies is calculated using EnergyPlus. The following conclusions were obtained: (1) By summing the demand exhaust rate of the cookers with that of the fume hoods during the operation of multiple cookers, the pollution control effect can still be satisfied. Moreover, the airflow can be reduced by 20% through airflow optimization. (2) During summer, the conditioned airflow should constitute 30% of the total make-up air volume, with an air supply temperature of 22 ℃. Conversely, in winter, the conditioned airflow should comprise 40% of the total make-up air volume, with an air supply temperature of 14 ℃. (3) It is advisable to use a personalized conditioned air supply to create a local thermal environment, effectively reducing the energy consumption of ventilation and air conditioning systems. The energy-saving rates achieved through airflow optimization and on-demand ventilation are 51% and 71%, respectively. [ABSTRACT FROM AUTHOR]

Natural building materials, including bioaggregates and biocomposites, have been making a comeback in recent years, in an attempt to minimize the Embodied and Operational Energy and Carbon (EE, OE, EC, OC) related to construction. This paper presents monitoring results of three buildings (two residential and one educational) built with such materials in the Mediterranean climate of western Crete. Temperature and relative humidity monitoring results show a very stable indoor environment behavior even when the buildings were unoccupied, thus not appropriately operated. Additional measurements undertaken and presented here include CO 2 concentration in the occupied residential building with a combustion heater; and blow-door tests to better understand infiltration issues related with such construction. Results analysis shows that such materials are appropriate alternatives, definitely in bioclimatic building design for the specific climate. Indoor conditions analyzed vis-à-vis the adaptive thermal comfort model are shown to be within the thermal comfort zone, almost for all climatic conditions. [ABSTRACT FROM AUTHOR]

Model Predictive Control can cope with conflicting control objectives in building energy managements. In terms of user satisfaction, visual comfort has been proven in several studies to be a crucial factor, however thermal comfort is typically considered the only important aspect. Besides human well-being, visual comfort strongly impacts the productivity of the occupants in offices. Therefore, from an economic point of view, it is essential to include visual comfort in Model Predictive Control for buildings. In this paper semi-linear support vector machine is applied to learn suitable models for visual comfort measured by Daylight Glare Probability. The resulting model is incorporated into a Model Predictive Control framework, together with an autoregressive exogenous model accounting for the thermal dynamics of the building. The approach is validated through an extensive numerical case study, and the benefits of including visual comfort and blind control in the Model Predictive Control problem are evaluated. We observe that the proposed Model Predictive Control scheme ensures both the thermal and visual comfort constraints at the expense of 2.2 % to 7.2% higher energy consumption compared to the benchmark Model Predictive Control configuration, which considers only the thermal comfort constraints. [ABSTRACT FROM AUTHOR]

• Secondary students' thermal comfort was explored in the countryside throughout one year. • Comfort indicators and behavioral adaptation were determined in different seasons. • The applicability of the adaptive comfort model was demonstrated in different seasons. People experience four seasons every year, and their thermal comfort usually changes with the season. However, a little is known about the dynamic characteristics of secondary students' thermal comfort in the countryside under different seasons. This study aims to investigate thermal comfort of students in the countryside under various seasons and reveal the underlying mechanism. One year long-term field study was conducted in a countryside secondary school in Hengyang City, located in the hot summer and cold winter zone of China. A paper questionnaire was used to collect subjective thermal comfort. The surrounding physical environment was also measured. A total of 450 subjects voluntarily participated and returned 2349 valid datasets. The results indicated students had the lowest acceptance rate with temperature (71.9 %), humidity (74.9 %), and velocity (70 %) in summer season. Neutral temperature was 25.7 °C in summer, 19.2 °C in transition, and 14.9 °C in the winter. An inverted U relationship was found between perceived air quality and air temperature. Cold extremities (53.0 %), shivering (37.2 %), and stuffy nose (60.4 %) were prevalent in winter. Adaptive comfort model was only effective in the summer in naturally ventilated secondary school buildings. Estimated learning performance was the highest in transition and lowest in summer. Behavioral adaptation was determined by the relationship between air velocity clothing insulation and operative temperature. The findings of this study provide fundamental knowledge of thermal environment, subjective comfort, and health status in naturally ventilated educational buildings in countryside area. Engineers and designers can use professional comfort indicators to guide their future construction or renovation. [ABSTRACT FROM AUTHOR]

One of the major challenges with increasing penetration of renewable energy sources (e.g., solar and wind) is to maintain grid stability. Grid-interactive efficient buildings are regarded as a promising approach to advance the role buildings can play in energy system operations and planning. This paper evaluates the demand flexibility in a residential building located in Karlsruhe, Germany, incorporating multiple distributed energy resources, including a photovoltaic and battery system, an electric vehicle, an electric water heater and a heat pump. A multi-criteria optimization problem is formulated with model predictive control (MPC) for five cases of demand flexibility. The simulation results of five winter days show that the peak power during the peak periods can be reduced by 92%, 69%, 100%, and 100% for real-time pricing, demand limiting, load shedding, and load shifting, respectively. For the power tracking scenario, the MPC tracked the reference power profile successfully for 70% of the simulation time. Achieving demand flexibility does not necessarily cause an increase in energy costs. • Distributed energy resources include thermostatic loads, PV, battery, and electric vehicle. • Real-time pricing, load shedding, shifting, and power tracking are considered. • An approach to maximize load sheaving and shifting is proposed. • Providing demand flexibility does not necessarily increase energy cost. [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]

Post-occupancy evaluation (POE) is necessary to evaluate the building's performance in order to formulate future design development after its utilisation. This paper evaluates indoor thermal performance, sound pressure level, and illuminance in a multipurpose auditorium by combining zoning and activity-based POE. The evaluation was done in three activities: (A) student graduation, (B) theater performance, and (C) public lecture with different types of clothing preferences. Three different zones were used to define the precise location of the building improvement. Field measurements were taken for thermal performance, including Operative Temperature (T op), Humidity (Rh), Sound Pressure Level (dB), and Illuminance (lux). User perceptions were collected from 171 respondents (89 men and 82 women). The field measurement showed that average operative temperature varied across the activities with 26.15–25.68 °C, 25.47–24.95 °C, and 23.74–23.17 °C on activities A, B, and C, respectively. Activity A's (1 clo) room's operative temperature showed that 65% of data are outside the ASHRAE standard, indicating that the room condition is unsuitable for 1 clo. Activity A's TSV shows a slightly warm sensation (0.21 to 0.93) and is still in the comfort range. With the same clothing value (0.6 clo), Activity B's T op indicates a more suitable condition than Activity C's. The average TSV in Activity B indicates slightly cool (-0.54 to −0.90), with the lowest TSV found in Activity C (-1.09 to −1.41). Although TSV positively correlates with PMV , Thermal Preference (TP) revealed that the occupant expects cooler conditions in all activities. Sound pressure level and illuminance performed well according to all activities. This paper recommends chiller setting adjustment in the multipurpose auditorium based on activity characteristics. Combined POE based on zoning and activity can indicate which aspects of the auditorium need to be improved. [ABSTRACT FROM AUTHOR]

• 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]

• This paper presents a comprehensive review of cross ventilation research in buildings. • The advantages and disadvantages of different research methods are compared. • The ventilation models of cross ventilation are reviewed. • The influencing parameters of cross ventilation are summarized. • The future perspectives of cross ventilation research and practical applications are proposed. There is a growing body of literature that recognizes that natural ventilation plays a vital role in indoor air quality, thermal comfort and building energy consumption. This paper systematically reviews the previously published research of the most efficient and typical natural ventilation type - cross ventilation, aiming to present the main research topics in contemporary research and provide an agenda for future studies. The methodologies, airflow pattern, ventilation models and influencing parameters of cross ventilation were comprehensively summarized and discussed. The chained analysis and data-driven methods are the potential approaches to study cross ventilation more efficiently. The comparisons of different ventilation models of cross ventilation help to better understand the basic mechanisms that drive the cross ventilation airflow. [ABSTRACT FROM AUTHOR]

Diagrams of (A)conventional cool roofs, (B) super cool roofs, and (C) temperature-adaptive roofs whose color can change with temperature. [Display omitted] • Cool roofs are divided into conventional cool roofs, super cool roofs, and temperature adaptive roofs. • The use of cool roofs is limited by geography and climate, with the net cooling power of up to 150 W/m2 in dry, rainless, and clear sky areas. • The use of cool roofs in cities may cause light pollution problems, which can be alleviated by special structures or materials. • Not only does atmospheric water vapor affect the radiative cooling power of cool roofs, but in turn, cool roofs can increase the water vapor content above the roof. • The large-scale use of super cool roofs may affect the urban wind field. Cool roofs play a significant role in mitigating urban heat islands, improving indoor thermal comfort, and saving energy. In recent years, with advances in the manufacturing of nanophotonics and metamaterials, researchers have developed super cool roofs where the surface temperature remains below the air temperature in direct daylight and temperature-adaptive roofs where the solar reflectance or thermal emissivity can change with temperature. This paper reviews the research progress and status of conventional cool roofs, super cool roofs, and temperature-adaptive roofs. This paper affirms the role of cool roofs in mitigating urban heat islands and energy conservation. And this paper also summarizes some of the crucial issues that cool roofs may face when used in cities. The effects of cool roofs on urban wind fields, planetary boundary layer heights, and pollutants above cities as well as the effects of sky view factor, atmospheric humidity, dust, and aging on the performance of cool roofs are discussed. The results show that the use of cool roofs is limited by geography and climate. The net cooling power can reach 150 W/m2 in dry, rainless, and clear sky areas. Cool roof technology is less effective in hot and humid climates because the first atmospheric window is affected to varying degrees by the increased radiation medium in the atmosphere, while the second atmospheric window is nearly closed in hot and humid climates, weakening the terrestrial long-wave radiation entering space. The use of cool roofs in warm and humid climates (over 80% relative humidity, with temperature over 24 °C) for most summer nights may limit the radiative cooling performance of the cool roof. The large-scale use of cool roofs in cities near huge lakes or seas may affect the urban wind field, causing a cooling island effect and a local build-up of pollutants. Finally, an outlook on the research prospects of cool roofs was given to provide ideas for further research. [ABSTRACT FROM AUTHOR]

Abstract The assessment of building energy performance through dynamic simulations has been increasing significantly in recent years since it represents a key strategy for the correct design of highly efficient buildings. Results of dynamic energy simulations are affected by many uncertainties, and its reliability depends on the accuracy of the input variables. One of the most influential variables is the climate surrounding the building, a reason why the use of accurate weather data files is essential, but experimental datasets are not always available. In this context, this paper analyses numerical weather datasets obtained from different regional climate models by comparing them with real data; in addition, it evaluates their impact on the energy performance of a historical building in Asunción through dynamic simulations. The database of five different weather data sources is compared with observed meteorological data in order to assess their accuracy through statistical analyses. Moreover, some methodologies to estimate diffused and direct components of the global solar radiation are evaluated, with the objective of solving the problem of missing direct and diffused solar data components from the meteorological codes. Subsequently, weather data files are generated to quantify the influence of measured/simulated meteorological data on the evaluation of building energy performance. The results obtained in this paper show that the simulated meteorological data agree very well with real observations for the year under study. Also, the simulations of the building energy performance delivered similar values to those obtained using the real weather dataset. Therefore, the regional climate models can represent a reliable tool for building energy performance assessment, and mainly for the calibration of building energy models when measured weather data is not available. [ABSTRACT FROM AUTHOR]

Highlights • Calibrated models used to improve accuracy of predicted absolute savings from deep retrofit solutions. • Calibration method using in situ test results validated against pre- and post-retrofit measurements. • In situ test results presented for fabric performance of solid wall no-fines concrete dwellings and for traditional and innovative external wall insulation systems. • Co-pressurisation test results shown to have a significant impact on modelled energy performance. Abstract There remains a significant number of occupied and uninsulated solid wall dwellings in the UK. Deep retrofit is often required for these buildings to become energy efficient but it is difficult to determine how these buildings will respond to retrofit without a detailed understanding of their fabric thermal performance Greater certainty can however be achieved by combining theoretical models and practical field tests, prior to the design of retrofit programmes. This type of approach can then be used to inform and optimize the design of retrofit interventions. This paper presents results from a series of in situ fabric performance tests undertaken on two no-fines concrete, conjoined dwellings pre- and post-retrofit and demonstrates how empirical data can be used to inform and calibrate the thermal performance of dynamic simulation models (DSMs). This is a particularly pragmatic calibration method as it eliminates the need for actual weather data, which is expensive and prohibitive to collect and collate. The DSM inputs and outputs were compared with those obtained from Standard Assessment Procedure (SAP) calculations. The results illustrate how the fabric performance of no-fines concrete can vary between similar house types within the same development. This research also validates the effectiveness of the calibration methodology that uses the whole house Heat Transfer Coefficient (HTC) as the qualifying metric. Furthermore, results also emphasize the importance of appropriately characterizing the physical properties of existing buildings before designing retrofit strategies. This paper contributes to the growing knowledge base concerned with the energy performance gap. In this instance, SAP predicts higher absolute savings then measured in situ which is problematic when assessing the financial viability of retrofits. [ABSTRACT FROM AUTHOR]

New smart building technologies that offer continuous dynamic optimization of Heating, Ventilation, and Air Conditioning (HVAC) control hold promise to advance building operations for efficiency and grid response. These technologies use data from the control system to determine the analytically optimal setpoints, and then write back the optimal setpoints into the control system to minimize system energy consumption or costs. There are limited studies documenting field validations of these technologies. This paper presents the results from a long-term field evaluation of a model-predictive HVAC optimization system that installed in four commercial buildings. Energy savings analysis was conducted based on pre/post submetered energy use. Across the cohort of evaluation sites, HVAC savings following the implementation of the optimization system were mixed, ranging from 0–9%. Analysis of site operational data showed that occupant comfort was neither positively nor negatively impacted. Key technology adoption considerations and recommendations are summarized in the paper. The technology performs best when HVAC systems are in good working condition, and can be exercised to achieve the full range of its optimized setpoints–however it may not provide extensive additional savings over cases where best practice sequences of operation and reset strategies are already comprehensively implemented. [ABSTRACT FROM AUTHOR]

This paper provides a review of the literature concerning the impact of temporarily increased cooling setpoint temperature on occupant thermal comfort during demand response (DR) events in commercial, air-conditioned buildings. We address concerns regarding thermal comfort as it relates to zone temperature modifications that may be implemented as a part of DR measures. Increased zone setpoint temperatures during the cooling season can adversely affect building occupants physically and psychologically, and impair their perceived indoor air quality and self-estimated performance. In some cases, however, improved occupant thermal comfort due to warmer zone setpoint temperatures during DR events has also been reported. In order to reduce the negative impacts on building occupants, DR must be implemented with careful control and monitoring. There are significant differences in assumptions made about the way people would respond to a thermal environment between the static heat balance model and the adaptive approach, with the adaptive approach offering a wider range of acceptable indoor temperatures. Therefore, application of the adaptive approach could be one option to improve building energy performance by taking advantage of occupant adaptive behaviors during DR events. Depending on the building services and systems available, expectations of the occupants, and the control options they are given to adjust to their thermal environment, occupants could potentially adapt to temperatures higher than what are currently being practiced in buildings. However, an upper limit threshold for temperature modifications, even if temporary ones, must be recognized to minimize adverse impacts on building occupants prior to DR implementation. Therefore, the ideal goal would be to develop menthods that would identify an optimum balance between energy consumption and the building occupant thermal comfort before applying DR strategies. Prior review papers relevant to DR have generally concentrated on the energy saving potential alone, or where energy savings have been prioritized over occupant thermal comfort. This paper reviews implementation of DR from the perspective of occupant thermal comfort and presents a summary of the most relevant experimental and field studies regarding occupant thermal comfort during DR events in commercial, air-conditioned buildings. [ABSTRACT FROM AUTHOR]

The main purpose of this research is to evaluate the thermal-comfort environment in an office building served by a liquid-desiccant and indirect-and-direct evaporative-cooler-assisted 100% outdoor-air system (LD-IDECOAS). This research presents a method for evaluating the thermal environment via a series of energy simulations using the TRNSYS 17 program, integrated with an engineering equation-solver (EES) program. The supply air (SA) temperature is estimated according to the LD-IDECOAS seasonal operation modes proposed in previous research. The indoor-air conditions are estimated under the assumption that the relative humidity of room air was maintained at the set values by auxiliary humidification systems. Then, the predicted mean vote (PMV) values are estimated using the given indoor environment conditions. In this paper, the indoor-air conditions and PMV values for each LD-IDECOAS operation mode are represented. A detailed analysis of the impact of the indoor-air conditions on the PMV is provided in this paper. Furthermore, the simulation results for LD-IDECOAS were compared with those for a conventional variable-air-volume (VAV) system to evaluate the thermal environment in a building served by LD-IDECOAS. The PMV values with LD-IDECOAS showed that the thermal environment in a conditioned space is generally in compliance with ASHRAE Standard 55. Consequently, it is concluded that using LD-IDECOAS in an office building can produce energy savings with an acceptable level of thermal comfort. [ABSTRACT FROM AUTHOR]

• The physiological equivalent temperature (PET) and the universal thermal climate index (UTCI) are considered adaptive thermal comfort evaluation indices applicable to transition space. • The strong wind is prone to occur in winter on Huajiang campus. It is important to take precautions against the discomfort caused by a strong wind. • The outdoor thermal comfort condition of Huajiang campus in summer is better than it in winter. • Adjusting the coverage of lawn, marble floor, water surface and landscape trees can effectively regulate the microclimate of the library's inner courtyard space. The inner courtyard is an important transition space for mass exchange and heat transfer between the internal space of courtyard buildings and the external environment. A good layout of courtyard space is conducive to building energy efficiency and human thermal comfort. In the paper, we analyze the impacts of different design schemes of the spatial layout on the microclimate of inner courtyard space using field measurements and numerical simulation methods. The analysis of the measured data presents the main meteorological factors affecting the thermal comfort of the courtyard. The magnitude of the effects is ranked as air temperature, total solar radiation intensity, near-surface air flow rate, and relative humidity. Results of the ENVI-met simulation show that changing the cover of different underlying surface types leads to different microclimate regulation effects in the sense that the temperature and relative humidity in summer drops up to 3.53 °C and 15.59%, respectively and in winter increase up to 3.97 °C and 37.21%, respectively. This paper proposes that lawn ground, marble ground, water surface and landscape tree coverage of 25%, 25%, 50% and 75%, respectively, are suitable design schemes for the inner courtyard space of library. [ABSTRACT FROM AUTHOR]

Personalized thermal sensation models play a crucial role in ensuring occupant's thermal comfort satisfaction and improving building energy efficiency. However, an adaptive and accurate personalized model that can be easily implemented in real life is still challenging. This paper investigates the influencing factors of thermal sensation vote (TSV) and proposes a personalized regression model that only uses a single local skin temperature as the key indicator. A survey is conducted with forty subjects aging from 20 to 59 years old. The relationship among ambient temperature, skin temperatures, and subjective TSV is analyzed. The forehead temperature is recommended as the key indicator for prediction because it exhibits a strong correlation with ambient temperature and TSV, and it is easy to capture. Furthermore, the impact of individual characteristics on TSV is investigated. The proposed model effectively captures and compensates for individual differences by incorporating subjects' set point skin temperature and body fat percentage (BF%). The proposed model can be readily applied in real-life scenarios due to its minimal requirement for occupant's feedback and its higher accuracy compared to other models. Specifically, it exhibits a significantly lower Root Mean Square Error (RMSE) of 15.8 %, 9.4 %, and 65.2 % compared to the Support Vector Regression (SVR) model Zhang's model and Zhou's model. Moreover, the proposed model showcases the lowest mean absolute error among the compared models. This approach of developing a personalized regression model based on local body temperature holds promise for future international ergonomic standard development. [ABSTRACT FROM AUTHOR]

• A metodology for evaluating comfort temperature ranges is carried out. • New evaluation metrics regading thermal comfort and energy savings are proposed. • Quantitative evaluations of modifying thermal comfort ranges are provided. The selection of a suitable indoor temperature is a challenge to society, since its relationship with thermal comfort and energy consumption. The adaptive thermal comfort theory addresses this problem relating indoor with outdoor temperatures and based on that, defines temperature ranges. This paper defines a fuzzy logic-based methodology to assess the suitability of indoor adaptive temperature ranges proposed by existing regulations of the real thermal sensation of the occupants. For this purpose, the study suggests considering four indicators to evaluate the representativeness of different comfort ranges on the real preferences of the occupants. Based on that, four metrics are proposed for interpreting the needs of the occupants of a building and the changes required to the temperature ranges to satisfy such needs. To validate the proposed methodology, questionnaires on the thermal sensation of the occupants of office buildings considering three case studies (Mediterranean, Europe, ASHRAE) are used, showing the results obtained the representativeness of adaptive comfort ranges for such databases. The feasible introduction of this methodology in a conditioning systems would assist in decision making regarding energy efficiency, thermal comfort and a balance between them. [ABSTRACT FROM AUTHOR]

[Display omitted] • Infrared technology enables non-invasive temperature measurement. • Existing literature related to personal thermal comfort using infrared technology was reviewed. • Measurement equipment, experimental conditions, subject's information, and analytical methods were analyzed. • Accurate predictions should be translated into control commands for the equipment at different scales. • Diverse application scenarios including car cabin, sleep, and outdoor environments were discussed. Personal thermal comfort studies are crucial for balancing both human comfort and building energy savings. Thus, personal comfort models (PCMs) are expected to play a pivotal role in the development of smart buildings. Infrared technology has received significant attention from researchers because of its non-intrusive nature for collecting personal data. This systematic review examined 36 personal thermal comfort studies that employed infrared technology over the past decade. The review analyzed the (1) infrared devices, (2) experimental designs, (3) subjects, and (4) analysis methods and results. The review found that most studies were experimental and focused on exploring feasibility at a theoretical level, while the number of practical application studies was limited. The accuracy of infrared devices was identified as a primary concern for researchers, and some studies proposed methods to mitigate measurement errors. Most studies included young subjects and examined single clothing insulation and metabolic rates, limiting the generalizability of the corresponding PCMs, which were mainly constructed using machine learning. To facilitate data sharing and comparison of results and to overcome the limitations in terms of applicable populations and application scenarios, the review suggests that standardized data collection and processing should be used in future studies. Furthermore, the paper proposes the integration of PCMs and personal comfort systems, which are two hotspots in personal thermal comfort research, to achieve cooperative applications. Finally, the study discusses the future applications of infrared technology in scenarios such as vehicle cabins, sleep areas, and outdoor environments, considering their unique characteristics. [ABSTRACT FROM AUTHOR]

Traditional air-conditioning systems are energy intensive and contribute to higher operational costs especially in summer. This paper examines and compares the performance of two cooling systems in a room: one with a cooling tower connected thermally activated building system (TABS) combined with a fan coil unit (FCU), and the other with a conventional inverter split air-conditioner (AC). Natural ventilation adversely affected indoor air temperatures in TABS room while integrating FCU operation reduced the temperature by 5 °C and AC provided the most comfortable temperature. Thermal comfort survey of three occupants showed significant inconsistencies with Fanger model particularly for TABS with FCU and TABS without ventilation cases, as occupants felt comfortable indicating the positive effect of only sensible cooling. Energy consumption studies show that TABS in closed condition and with natural ventilation as the most energy efficient with AC being least efficient of the four systems. In terms of overall comfort and energy consumption for continuous operation throughout the day, TABS integrated with FCU was deemed the best option. [ABSTRACT FROM AUTHOR]

In response to the increasing demand for thermal comfort and the rising trend of building energy consumption in the hot summer and cold winter (HSCW) zone of China, there is an urgent need to implement higher standards of energy retrofit programs for existing residentials. Practical strategies and technical solutions still need to be improved in China. The Passive House standard (and its EnerPHit standard) aims to achieve ultra-low operational energy consumption through passive strategies. However, studies and examples of passive houses and low-energy buildings are rare in hot climates, especially in the HSCW zone of China. This paper presents the representative of the existing residential in Guilin, China. Simulation modeling through DesignBuilder and a sensitivity analysis were performed to conclude that airtightness, envelope, glazing type, and roof are the most critical factors affecting the energy consumption of the building. Furthermore, the combined solution was validated by optimizing the different retrofit parameters, resulting in a model that meets the energy objectives. The feasibility of the combined solution was also analyzed from the energy, economic, and thermal comfort points of view. Ultimately, the optimal solution that meets the objectives is obtained through a multi-criteria decision making (MCDM) approach for a more sustainable building. The methodology and results of this study provide an effective decision-making process for designing and evaluating energy retrofits for typical residential buildings in the HSCW zone, as well as a rigorous basis for policymakers to update the design codes for retrofitting buildings in HSCW zone. [ABSTRACT FROM AUTHOR]

• An optimization algorithm is developed for determining optimal flexible workplaces. • The thermal comfort models in the objective function are learned from personal data. • The optimization allows a customized trade-off between thermal comfort and energy consumption. • The algorithm is verified using both collected data and the ASHRAE database. Due to distinct preferences across individuals, a large proportion of people are not satisfied with the thermal environments of their workplaces. Although recent studies have investigated flexible workplaces to meet the different preferences of individuals, the feasibility of adopting them to real-world environments is limited by the room capacity and potential for extra energy consumption. To address the knowledge gaps, this paper proposes a framework to jointly optimize thermal comfort and energy consumption of buildings through flexible workplaces by considering personal thermal preferences. A joint optimization algorithm that integrates building energy and personal thermal comfort models is developed based on the concept of the Large Neighborhood Search (LNS) algorithm. Analytical energy prediction models are obtained through Nonlinear Polynomial Regression (NPR) and personal thermal comfort models are established using Support Vector Machine Models (SVM). To verify the algorithm, a case study considering two scenarios (with and without existing personal thermal comfort data) is presented. The results indicate the proposed optimization algorithm can significantly improve the thermal comfort of the occupants while saving 22% and 14 % of energy consumption in the two scenarios, respectively. The proposed optimization method is valuable for building managers while adopting the concept of flexible workplaces. [ABSTRACT FROM AUTHOR]

Several studies have indicated that Economic Model Predictive Control (EMPC) of residential space heating systems can exploit the building thermal mass to provide demand response for the energy supply system by boosting the indoor air temperature prior to peak load periods. The practical uptake of EMPC is thus dependent on whether residents accept the fluctuating indoor air temperatures induced by this form of EMPC. Evidence on this aspect is scarce but a few studies indicate in hindsight that it might be important to explain the economic and environmental benefits of an EMPC if residents are to abandon their current preferences and practices in favour of an EMPC concept. The objective of the study reported in this paper was therefore to investigate whether residents of three single-family homes actually would accept the fluctuating indoor air temperature induced by EMPC when being aware of environmental and/or economic benefits. The results suggest that residents are willing to accept the fluctuating indoor air temperature being aware of economic and environmental benefits – as long as the fluctuations do not make them feel too cold. [ABSTRACT FROM AUTHOR]

• Statistical analysis of the performance of a green wall in a Mediterranean climate. • Irradiance is discarded as a variable affecting the adjacent temperatures reduction. • Maximum reduction of 0.63 °C in summer and 0.54 °C in winter at 1 m from the south facade. • Maximum reduction of 2.3% HR in winter at 1 m from the south façade. • Reduction average of 0.9% HR in summer at 1 m from the south façade. A study has been performed to quantify the impact of a green wall temperature reduction in a continental Mediterranean climate. This paper presents the results of a monitoring campaign during the summer and winter of 2021–2022. First, a database was elaborated with information on air temperature and relative humidity at four different distances from the wall (0.25, 0.50, 0.75, and 1 m) and irradiance in the vertical plane. Secondly, a statistical analysis was carried out to determine whether there is a correlation between these variables and whether there are statistically significant differences between them at different distances from the wall. Results show a strong positive correlation between air temperature recorded by sensors and the ambient air temperature for all seasons and between air temperature and relative humidity in summer. The ANOVA shows that the green wall reduces the temperature and relative humidity with statistical significance for most of the cases. These results confirmed the great capacity of green walls to improve the urban microclimate, especially during summer, by reducing air temperatures, providing evidence that greening the building envelope can complement conventional city green infrastructure and provide multiple ecosystem services to dense urban contexts. [ABSTRACT FROM AUTHOR]

This study assesses the impacts of sustainable urban development adapted to climate change in the city of Stuttgart, Germany. We use the state-of-the-art meteorological modelling system PALM-4U to simulate the microclimate and outdoor thermal comfort of the development site Neckarpark during a heatwave. We compare the atmospheric conditions of the current urban structure before the development project (2018) and the future state, representing the new district after completion (2025). Our results indicate that the restructuring barely affects surrounding neighbourhoods, but leads to mean near-surface air temperature increases in the centre of development between ▪ and ▪. Differences in Physiologically Equivalent Temperature (PET) show a heterogeneous pattern at daytime, with a large amplitude and temporal variability in the diurnal cycle (▪). At night, the planned buildings increase the mean PET by ▪. The new buildings reduce the effect of adaptation measures designed to increase the cooling effects, i.e. urban trees and vegetation, amplifying the thermal stress during heatwaves. Our study confirms the complex composite impacts of urban restructuring due to the thermal and dynamic flow processes. The paper may serve as a guide for the use of meteorological models to assess microclimatic impacts of planned development projects, contributing to urban planning and adaptation strategies. [ABSTRACT FROM AUTHOR]

The objective of this paper is to optimize the passive design of newly-built residential buildings in hot summer and cold winter region of China for improving indoor thermal comfort while reducing building energy demand. In this respect, this paper investigates the performance of a representative apartment building in the city of Shanghai and evaluates the optimum solutions by using a developed optimization approach, which includes three major steps of 1) setting the model for multi-objective optimization, 2) sensitivity analysis for reducing the dimension of input variables, and 3) multi-objective optimization by using the Non-dominated Sorting Genetic Algorithm II (NSGA-II) coupled with the Artificial Neural Network (ANN), among which a novel indicator for evaluating the annual indoor thermal comfort of residential buildings of Shanghai named Comfort Time Ratio (CTR) is defined based on the modification of Szokolay’s theory in terms of bioclimatic analysis, and the impacts of passive design variables on the indoor thermal comfort and building energy demand in terms of different directions are comprehensively investigated. Results of the multi-objective optimization indicate that the residential buildings of Shanghai have a great potential in comfort-improvement and energy-saving. A series of novel optimal passive design tactics for residential buildings in Shanghai are derived accordingly which could be easily understood and conveniently carried out by the architects in practice. [ABSTRACT FROM AUTHOR]

In a traditional building design process (TDP), design variables are fixed sequentially, as opposed to integrated design process (IDP) which tends to avoid sequential design phases to create more sustainable buildings. First, a reference building is introduced and an energy model based on TRNSYS is presented to determine the energy consumption and comfort in the building. The model is validated based on energy bills, certified simulations and literature. Then, the paper performs an extended sensitivity analysis (SA) of 30 design variables with respect to different performance criteria related to energy consumption and comfort, based on a TRNSYS model. Three SA techniques were used, namely standard regression coefficients (SRC), partial rank correlation coefficients (PRCC) and Sobol indices. Results show that all three techniques yielded a similar ranking of the importance of the variables for most model outputs. Interactions between variables were identified with second-order Sobol indices. In the second part of this paper, a traditional design framework was adopted in which sets of variables were fixed sequentially. A SA was performed at each phase of the process, assuming fixed values for parameters chosen in previous design phases. Results show that fixing variables during the phases of a traditional design process tends to reduce the probabilities of finding low-energy consumption designs. Moreover, the influence of some variables was found to change during the design phases. [ABSTRACT FROM AUTHOR]

Public space is very valuable for a variety of community activities. Open public space comfort is one of the main indicators that provide its enjoyability, attractiveness and liveability. Having in mind that the climate conditions and the implemented urban design are influential in providing pedestrian thermal comfort, this study will focus on physical attributes of used pavement materials and their impact when they are exposed to high summer temperatures as well as on thermal comfort of the users of open public spaces. The methods that were used in the analysis include the method of direct surveying of inhabitants, the method of observation and the method of measuring the characteristics of different materials used for pavement in the pedestrian zone. The measuring of the current surface temperature of different paving materials used for pedestrian zone was performed during the summer season (July, August, and September) of 2015 in the central city zone of the city of Niš, with the goal of determining the maximum heating up of horizontal surfaces, i.e. pavements. The survey was done in July 2015 in the main square in Niš. The measuring determined that in the same conditions, various materials yield various maximum temperatures. It was also concluded that the type of material, colour, roughness and shading of an area affect the heating up of pedestrian surfaces. The purpose of this paper is to highlight the complexity of the relationship between microclimate thermal comfort in public open spaces and the measured temperature of the pavement surface, and to emphasize the importance of this relationship in the context of contemporary urban design. The paper presents the case study of pedestrian spaces in the central area of the City of Niš in Serbia. [ABSTRACT FROM AUTHOR]

This paper presents a system for the real-time analysis of human skin temperatures using sensor fusion and thermal image recognition. The aim of this work is to introduce an open and extensible framework that supports multi-modal sensor input with a focus on merging optical data and conventional sensor input for advanced thermal comfort analysis. The goal is to obtain a more complete representation of a person in various indoor climatic conditions. Methods proposed in this paper are important for research and industrial applications with respect to the real-time analysis of thermal comfort and human physiology in indoor climates. Although this paper mainly focuses on the analysis of skin temperatures, the proposed architecture is conceived for being extendable for statistical evaluation and numerical models. Arbitrary software components can be integrated as data sources and sinks by means of a conventional TCP/IP networking interface. Main contributions of this paper are a general architecture for the fusion of multi-modal sensor input using a centralized data server structure, a method for combining depth-map based face and pose tracking with a thermal imaging device and preliminary studies demonstrating the behavior and validity of the system. [ABSTRACT FROM AUTHOR]

The appraisal of indoor environment quality in residential dwellings presents a range of technical challenges. Indoor environment quality (IEQ) is often described as having thermal, visual, aural and olfactory dimensions, each of which is assessed subjectively by the resident. While it is possible to objectively assess physical parameters relating to these aspects of IEQ, either directly or indirectly, resident satisfaction with the environment is determined subjectively so must be inferred. In the field study of thermal comfort (FSTC) approach, objective physical measurements are collected simultaneously with resident preference and sensation information, usually via a diary or written survey. This research paper explores a new approach to residential IEQ appraisal which extends the FSTC approach to the visual, aural and olfactory dimensions using a low-cost data collection system based upon the Arduino microcontroller platform. The paper describes the design developed, presents early validation results and draws preliminary conclusions. [ABSTRACT FROM AUTHOR]

In times of great transition of the European construction sector to energy efficient and nearly zero energy buildings (nZEB), a market observation containing qualitative and quantitative indications should help to fill out some of the current gaps concerning the EU 2020 carbon targets. Next to the economic challenges, there are equally important factors that hinder renovating the existing residential building stock and adding newly constructed high performance buildings. Under these circumstances this paper summarises the findings of a cross-comparative study of the societal and technical barriers of nZEB implementation in 7 Southern European countries. The study analyses the present situation and provides an overview on future prospects for nZEB in Southern Europe. The result presents an overview of challenges and provides recommendations based on available empirical evidence to further lower those barriers in the European construction sector. The paper finds that the most Southern European countries are poorly prepared for nZEB implementation and especially to the challenge/opportunity of retrofitting existing buildings. Creating a common approach to further develop nZEB targets, concepts and definitions in synergy with the climatic, societal and technical state of progress in Southern Europe is essential. The paper provides recommendations for actions to shift the identified gaps into opportunities for future development of climate adaptive high performance buildings. [ABSTRACT FROM AUTHOR]

Cooling of buildings is an essential target for engineers and builders in the hot arid climate of Egypt. Performance of inclined solar chimney with passive cooling tower (SCPC) was studied. The system was integrated into a single room built in Assiut University (El-Gorib site) in Assiut, Egypt. Testing of indoor environment for the room with passive cooling was done during August and September 2015. A passive cooling technique was integrated inside a short wind tower made from expanded paper (wet pad) 0.1 m thick. A water tube was installed on the top of the expanded paper with small nozzles. Water is recirculated through the system using water pump. A reduction of room indoor temperature was observed with the integrated system (SCPC). There is a significant reduction of indoor temperature between 6 and 7 K due to passive cooling with surface temperature 19.4 °C for the cooling pad. The relative humidity did not exceed 57% most of the time. The maximum air speed inside the solar chimney was 3.5 m/s under the effect of a high solar radiation of 890 W/m 2 . The findings show that SCPC system achieves comfortable thermal conditions with a significant improvement in building energy conservation. The result of development this new cooling system helps to develop building code for low energy houses in Egypt and propose a new system to be integrated in the housing project of people with low income. [ABSTRACT FROM AUTHOR]

This paper pays tribute to Povl Ole Fanger, the late professor at the Technical University of Denmark. His scientific studies, focused on the main parameters affecting indoor environmental quality, have inspired (and still inspire) professional design engineers and academic researchers on human thermal comfort and indoor air quality over the last five decades. In addition, he strongly contributed to the creation of a “European School” that addressed engineering issues and was well integrated with the American School, which was characterised (at that time) by a physiological approach. Ten years after his death, this paper is a memorial of his research in the field of thermal comfort and some aspects of indoor air quality. Only the original papers of this Danish scientist will be discussed. The analysis of each single topic of his research and of its impact on past and present research would require more space than would be available in a review article. The authors are confident that the research described in this paper will serve as a beacon for researchers working on thermal comfort now and in the future. [ABSTRACT FROM AUTHOR]

This paper provides a study of the optimal scheduling of building operation to minimize its energy cost under building operation uncertainties. Opposed to the usual way that describes thermal comfort using a static range of air temperature, the optimization of a tradeoff between energy cost and thermal comfort predicted mean vote (PMV) index is addressed in this paper. In order to integrate the calculation of the PMV index with the optimization procedure, we develop a sufficiently accurate approximation of the original PMV model which is computationally efficient. We develop a model-based periodic event-triggered mechanism (ETM) to handle the uncertainties in the building operation. Upon the triggering of predefined events, the ETM determines whether the optimal strategy should be recalculated. In this way, the communication and computational resources required can be significantly reduced. Numerical results show that the ETM method is robust with respect to the uncertainties in prediction errors and results in a reduction of more than 60% in computation without perceivable degradation in system performance as compared to a typical closed-loop model predictive control. [ABSTRACT FROM AUTHOR]

Modern cities and their architectural structures undergo significant functional and physical changes. In recent years, the interventions on building envelopes have increased. Therefore, it is necessary to analyse potential remodeling of glass facades, along with applying the concept of smart technologies, in order to increase energy efficiency of the existing buildings. This paper analyses the modernization process of devastated glass façade of the tall Slavija hotel, built in 1960s in Belgrade, Serbia, taking into consideration some positive examples of transformation and reskinning of buildings, where the aspect of medialization is an active part of urban renewal. The subject of this paper is the analysis of research findings about the improved thermal comfort of this building, after performing the replacement of its glass façade and converting the hotel building into an office building. Special attention was paid to the implementation of media technologies and final effects on energy balance of the newly designed facade. The proposed solution is supposed to evaluate the improved thermal comfort that was achieved by a radical renovation of the facade and by replacing the existing facade with a new single façade (double and triple glazed units), with media elements as well as without them. The research results are presented as proposals for improving EE public buildings by implementing the latest system of curtain walls in order to increase the value of the buildings. One of the most important criteria included in the process of energy refurbishment is technological improvement of the existing buildings, along with the presentation of media facades. The case study is based on EnergyPlus simulations. [ABSTRACT FROM AUTHOR]

Most existing commercial building energy management systems (BEMS) are reactive rule-based. This means that an action is produced when an event occurs. In consequence, these systems cannot predict future scenarios and anticipate events to optimize building operation. This paper presents the procedure of implementing a predictive control strategy in a commercial BEMS for boilers in buildings, and describes the results achieved. The proposed control is based on a neural network that turns on the boiler each day at the optimum time, according to the surrounding environment, to achieve thermal comfort levels at the beginning of the working day. The control strategy presented in this paper is compared with the current control strategy implemented in BEMS that is based on scheduled on/off control. The control strategy was tested during one heating season and a set of key performance indicators were used to assess the benefits of the proposed control strategy. The results showed that the implementation of predictive control in a BEMS for building boilers can reduce the energy required to heat the building by around 20% without compromising the user’s comfort. [ABSTRACT FROM AUTHOR]

This paper presents a method to optimally control a commercial building air conditioning operation based on building thermal physics and human behavior. Control plans are developed for zone cooling and according to occupancy patterns at zone levels, and using a novel response model developed in this paper. The thermal response model is a statistical model, which is built on the basis of insights gained from physics-based model of zone thermal behavior. The control model attempts to optimize cooling system scheduling on the basis of occupancy patterns, price signal from utilities and human comfort and productivity. The optimization follows an on-demand routine, such that zone level air conditioning starts at a time epoch that is optimal according to zone thermal response and cooling requirements. We toss the term “pre-occupy” control. We also develop, what we call, “post-occupy” control, where the system shutdown follows thermal inertia and cooling requirements at the time that the zone is expected to become unoccupied. The thermal response modeling of a zone and the two control modes are considered major contributions of this article. EnergyPlus reference models are used to train our models and illustrative examples are presented. [ABSTRACT FROM AUTHOR]

In recent decades there has been a growing awareness regarding energy consumption in buildings. Unfortunately, at a time when all building actors should get involved in the challenge to reduce energy consumption, designers cannot rely on effective tools to help them in their decision making process concerning airtightness. This literature review allows the identification of two important issues: new airtightness predictive models are complex to develop and existing airtightness predictive models do not meet the needs of designers and contractors. This paper is divided into three main parts in addition to the introduction and the conclusion. The first part deals with the key concepts of infiltration and airtightness, the second part with influencing factors and the third part with airtightness predictive models. These different chapters highlight a need for standardization regarding the metrics used for data presentation, parameters definition and statistical quantification. The lack of standardization hinders the development of a new airtightness predictive tool for designers and contractors. Along with the problem of standardization, supervision and workmanship are parameters that are difficult to model. Their significant impact can explain why designers and contractors find some existing models unreliable. This paper concludes that none of the existing models can be used in their present form as design tools. Further work should focus on the standardization of data presentation and on the development of a new airtightness predictive model. The first step in the development of such a model is to draw an appropriate classification of “air paths.” [ABSTRACT FROM AUTHOR]

• This study presents a comprehensive review on fan-use rates and effects in practice. • The main trigger of fan-use is a warm environment rather than building types. • Using fans elevates neutral temperature averages by 3 K in real buildings. • More than 15% air-conditioning-use rate is reduced by fan-use in buildings. • 3-K temperature extension is achieved by using fans for productivity not decreasing. This paper is a literature review of field studies on fan-use rates and their effects on thermal comfort, energy conservation, and human productivity. In the assessed literature, fans are more popular in Asia, and more used in mixed-mode (MM) and naturally ventilated (NV) buildings than in air-conditioned (AC) buildings. On the basis of collected fan-use models, probit regression models of fan-use rates and ambient environments were obtained and indicate that the essential trigger of fan-use is a warm environment rather than building types. This result helps us to understand the control behaviors and comfort requirements of occupants. Also, fans could provide benefits in three aspects: widening neutral temperatures, saving energy, and improving occupants' productivity. First, using fans in buildings elevates the neutral temperature and the upper limit of neutral zone (0.5 thermal sensation scale) averages by about 3 K in ranges from 25.7°C to 28.7°C and 27.5°C to 30.7°C, respectively. Second, fan-use reduces AC-use rates in MM buildings in summer. The regression models based on the collected AC-use rate models illustrate that, on average, AC-use is expected to be reduced by about 15% in summer when fans are used. Third, providing occupants access to fans could improve occupants' productivity. Based on the limited data available, a 3-K temperature extension is achieved by fans ensuring productivity not decreasing. This review could shed some light on the extension of the neutral temperature range, predictions of MM buildings' energy consumptions, and methods to enhance productivity. Additionally, this review suggests some valuable directions for future research on fans. [ABSTRACT FROM AUTHOR]

This paper aims to explore gender differences in thermal comfort under coupled environmental factors, as previous studies have primarily focused on air temperature alone. The experiment involved 27 subjects, 13 males and 14 females, who experienced 12 different combinations of air temperature and air velocity environmental conditions. The subjective responses and physiological parameters were collected and analyzed. In colder environments, especially when low air temperatures are coupled with elevated air velocity, significant gender differences are observed, as females feel colder, more uncomfortable, and perceive stronger drafts than males. In hotter environments, when high air temperatures are coupled with still air, males tend to feel more uncomfortable and prefer higher air velocity, compared to females. However, few gender differences are observed when high air temperatures are coupled with elevated air velocity. Under colder conditions, forearm temperatures show a stronger correlation with subjective responses, while under hotter conditions, facial skin temperatures demonstrate a stronger correlation, for both genders. Moreover, the Elevated Air Speed Model in ASHRAE 55–2020 is found to overestimates the cooling effect of elevated air velocity for both genders. The findings suggest that gender differences should be properly considered when designing indoor thermal environments, particularly under colder conditions. [ABSTRACT FROM AUTHOR]

An excellent way to obtain a detailed description of the air flows and temperature field in a zone is to perform accurate Computational Fluid Dynamics (CFD) simulations. Unfortunately, this is often prohibitive due to the powerful resources that are required, and the large computational times. As a consequence, several intermediate models between CFD and the standard well-mixed models have been proposed over the years. These are known as zonal models, and they aim at delivering sufficiently accurate predictions of the thermal comfort in a room, for long periods (months or even years), and with substantially shorter computational times. However, none of these models has yet been implemented in a building performance simulation (BPS) tool. In this work, we have developed and implemented a BLOCK zonal model [1,2] within the IDA ICE (BPS) software. A multi-node 1D model for the prediction of vertical temperature gradients is used, together with flow element theory and an appropriate algorithm for the estimation of view-factors in non-convex geometries with obstacles. The paper presents the theoretical background of the model along with advice on its range of applicability. Finally, the model is validated against several test cases, showing its suitability in predicting the thermal stratification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Impacts of reverse cycle air-conditioners (RCACs) during summer are examined. • Wellbeing impacts are studied via a survey of 283 Australian public housing tenants. • Positive and significant impacts on measures of health and housing suitability are found. • Households with RCACs increased summertime electricity expenditure by about A$40. • There is no significant impact on subjective reporting of energy bill stress. Heating and cooling upgrades can have important implications for energy bills and thermal comfort in public housing. However, more could be known about the specific impacts of such upgrades, including on tenant wellbeing. This paper examines upgrades delivered to public housing properties in the Australian Capital Territory, focusing on effects in summer. We analyze impacts of replacing existing heaters with energy-efficient reverse cycle air-conditioners (RCACs). The principal research question is: by how much does access to indoor cooling increase wellbeing among public housing tenants? The analysis is based on a survey of 283 residents carried out in March–April 2021. We use factor analysis followed by linear regressions and an instrumental variable approach. Positive and significant impacts are found on measures of health and housing suitability, including the reported ability of residents to concentrate. Households with RCACs increased their summertime electricity bills by around A$40 relative to control households, although we find no significant impact on subjective reporting of energy bill stress. The study is among the first to apply rigorous econometric techniques to examine causal impacts of indoor cooling in residential settings. [ABSTRACT FROM AUTHOR]