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This study investigates the impact of vertical greenery systems (VGSs) applied to several typical wall configurations on indoor thermal conditions in a building module situated in the Mediterranean climate of Catania, Italy. By means of dynamic simulations in TRNSYS vers.18, the research compares the thermal behavior of walls made of either hollow clay blocks (Poroton) or lava stone blocks against a lightweight wall setup already in place at the University of Catania. The primary focus is on evaluating the VGSs' capability of reducing peak inner surface temperatures and moderating heat flux fluctuations entering the building. The findings indicate that adding an outer vertical greenery layer to heavyweight walls can decrease the peak inner surface temperature by up to 1.0 °C compared to the same bare wall. However, the greenery's positive impact is less pronounced than in the case of the lightweight wall. This research underscores the potential of green facades in enhancing the indoor thermal environment in buildings in regions with climates like the Mediterranean one, providing valuable insights for sustainable building design and urban planning. [ABSTRACT FROM AUTHOR]

Thermal comfort is a significant aspect of human well-being and productivity, particularly in tropical and subtropical regions where high temperatures and humidity prevail yearly. However, research on indoor and outdoor thermal comfort in those regions is lacking when compared to other areas, and a significant gap exists in the comprehension related to the suitability and application of existing thermal comfort indices. This study intends to provide insights into existing human thermal comfort indices based on their applications in tropical and subtropical regions of Koppen climates for indoor and outdoor. PRISMA guidelines are used for conducting a systematic literature review using 86 articles. Of these, 38 were original thermal comfort indices articles and 48 were case studies (indoor and outdoor). This research discussed the most and least preferred indices as well as the approaches and parameters considered by the thermal comfort indices. The result shows that most efforts were made in temperate and continental climates to derive thermal comfort indices. For outdoor thermal comfort assessment, 72% of studies used Physiological Equivalent Temperature; 21% used Discomfort Index and Universal Thermal Climate Index. Whereas for indoors, > 90% of studies used the Predicted Mean Vote index and Operative Temperature. Overall, the used thermal comfort indices in reviewed studies underestimate the comfortable ranges observed in tropical and subtropical regions. The findings of this study can be utilized by researchers, urban designers, and planners to increase understanding related to human thermal comfort in tropical and subtropical climates. [ABSTRACT FROM AUTHOR]

The radiant systems come to the fore due to energy saving potential and good integration. The effect of different forms of cold surfaces on human thermal comfort is focused on its application. A novel natural convection-radiant evaporator for heat pumps was developed and its influence on thermal comfort was investigated. A numerical model of the chamber with the evaporator was established and verified with experimental results. Thermal comfort experiments were conducted in a climate chamber and the influence of its asymmetric and uneven cold radiation on the thermal comfort was investigated. Due to the limitation of PMV in uneven radiation situations, the revised predicted mean vote (RPMV) was proposed to assess the thermal comfort in asymmetric and uneven radiation environments based on experimental results. Based on RPMV, the influence of the surface area and temperature of the evaporator on thermal comfort was numerically analyzed. The results indicate that indoor air temperature and relative humidity, RPMV increase with the increase of plate temperature, but decrease with an increase in plate area. The most favourable indoor thermal comfort environment was obtained at an indoor air temperature of 28°C and relative humidity of 50%, which is 2°C higher than traditional air conditioning system. [ABSTRACT FROM AUTHOR]

Green roofs' (GR) positive impact on indoor thermal conditions in hot areas may have possible negative impacts during hot and cold weather. Most previous studies have focused on GR's positive effects as a standalone strategy without mitigating these side effects of GR application. This study contributes to a more comprehensive understanding of the impact of GR and how to mitigate the negative aspects by integrating it with other passive techniques (natural ventilation and thermal insulation). Therefore, this study experimentally compares the seasonal impact of various soil layer configurations, integrated with natural ventilation, on improving Indoor Thermal Comfort (ITC) throughout the day in summer and winter. Field experiments were conducted using two identical validated test boxes. The results revealed that clay soil reduced Indoor Air Temperature (IAT) during the daytime in summer by up to 4.7 and 4°C for low and high soil thickness, respectively. Increasing clay soil thickness improved average IAT during the daytime in summer and winter by up to 6.49% and 2.61%, respectively. Additionally, adding thermal insulation is preferred in winter, while uninsulated soil had a slight positive effect on IAT and Indoor Relative Humidity (IRH) in summer. The use of natural ventilation at night and closed-ventilated systems during the daytime in summer and winter is recommended. Clay soil could save cooling and heating energy by up to 34.8% and 12.18%, respectively. These findings might inform designers by adjusting different GR soil parameters and the importance of natural ventilation in improving multi-seasonal thermal and energy performance. [ABSTRACT FROM AUTHOR]

This study evaluates the indoor thermal benefits of seven bricks, and their combination with cavity walls, Vertical Greening Systems (VGS), and Expanded Polystyrene (EPS) insulation in a semi-arid Indian climate using EnergyPlus simulations. For walls with VGS and exterior EPS with higher heat capacity, peak summer Operative temperatures (Top) reduced up to 2.3°C, followed by cavity walls and EPS on middle of the wall (up to 1.3°C) compared to their respective bare walls. Interior EPS raised Top by up to 0.7°C. VGS and EPS minimized heat flux fluctuations due to their lower Decrement Factor. VGS exhibited superior indoor thermal comfort, with more occupants satisfied for longer durations compared to exterior EPS. This study suggests that applying VGS or EPS on the exterior (regardless of brick type) is more effective in enhancing indoor thermal comfort during hot days in semi-arid regions. [ABSTRACT FROM AUTHOR]

Thermal bridges significantly influence the energy performance of buildings. However, their impact varies depending on the type of thermal bridge, climate conditions, construction methodologies, and geometric characteristics of the building. On the Spanish Mediterranean coast, buildings with large balconies are predominant. Nevertheless, the Spanish energy efficiency regulations do not adequately specify the thermal bridges at the junctions of balconies with facades, leading to a lack of consideration for their influence in the majority of architectural projects. The objective of this study is to qualitatively and quantitatively assess the impact of such thermal bridges on the energy efficiency of buildings in a dry Mediterranean climate (BShs) within a warm semi-arid climate (BSh). As a case study, the influence of this thermal bridge is analyzed in two residential buildings located on the Mediterranean coast of southeastern Spain. The study also examines the modification of various construction parameters of this thermal bridge and determines the optimal design parameters to reduce its thermal transmittance. The results demonstrate that the energy needs caused by thermal bridges account for approximately 40% of the total annual energy needs of the studied residential buildings. Balcony thermal bridges account for 25% to 40% of the energy needs caused by all thermal bridges. The lack of differentiation in Spanish standards between balcony–facade and facade–slab edge junctions causes an imprecision in calculations equivalent to 12% of the total annual energy needs of dwellings. The novelty of this research lies in highlighting that current regulations and calculation programs need improvement to better characterize balcony thermal bridges and enhance the accuracy of building energy efficiency calculations. [ABSTRACT FROM AUTHOR]

With the rapid development of the national economy, increasing attention has been given to the living environment in rural areas, especially indoor thermal and wind environments. This study conducted on-site measurements and questionnaire surveys during winter in the indoor environment of five villages in northeastern Sichuan. Eighty-nine traditional residences were selected to investigate their fundamental characteristics, indoor thermal environment, humidity conditions, and comfort levels. Questionnaires and comparative experiments were also conducted with natives and locals. This combination of objective data and subjective feedback provides a comprehensive perspective for assessing the indoor thermal environment. The results showed that when expressed as neutral temperature and humidity, the temperature difference was 2.36 °C, with little humidity difference. Residents exhibited higher tolerance towards the local thermal and humidity environment than nonlocal volunteers, who showed greater sensitivity to it. In addition, residents had a Predicted Mean Vote (PMV) value of −0.69 and a heat acceptance value of −1.78, while non-local volunteers had a PMV value of −0.76 and a heat acceptance value of −1.32. A detailed evaluation and analysis of the relationship between the indoor thermal environment and human comfort of local residential houses was carried out, providing technical guidance for energy conservation and thermal insulation of local buildings.

Energy consumption in the building sector justifies the necessity of knowing the thermal comfort perception of vernacular and modern architectural types, based on which a correct recognition was reached for the design of buildings suitable for the climatic conditions of each region. It should be determined that the different types of modern and traditional architecture are in the comfort level in harsh hot climate conditions and how much energy they consume to reach the comfort level. Despite consideration of energy consumption and thermal comfort in different buildings in Iran, there is no clear framework for evaluating these two parameters in different buildings and comparing them. This research aims to compare the indoor thermal comfort levels of vernacular architectural buildings and modern buildings in Iran's semi-hot and dry climate at the peak of summer heat and determine their energy consumption to reach the comfort level. This study has been accomplished by collecting field data, examining the indoor predicted mean vote (PMV) index of the buildings, and comparing them. It was found that rock-cut architecture buildings are in better thermal comfort conditions without energy consumption due to the use of groundmass temperature and low heat exchanges between the indoors and outdoors because of the thermal phase of the materials and the thickness of its layers. The indoor PMV average of rock-cut buildings in summer is −0.61; in modern buildings, it is 0.77, while these two building complexes are in the same climate and close. Also, the energy consumption to reach the comfort level in rock-cut buildings is zero, while modern buildings consume an average of 7.7 kW of electricity daily. The research results will lead to recognizing and modeling the climate design of vernacular architecture, which can be used in today's architecture to reduce energy consumption.

This study investigates strategies to optimize the thermal environment and energy efficiency of rural dwellings in Yulin, China. Temperature, humidity, and solar radiation were monitored in three typical courtyard houses. Standard Deviation analysis revealed issues with indoor comfort and enclosure performance. Renovation approaches were proposed involving layout changes and envelope improvements. Simulations using Ecotect demonstrated the modifications could increase average indoor temperatures by 2.8 °C and reduce fluctuation ranges. This study provides an evidence-based methodology for enhancing rural home thermal comfort through climate-responsive design strategies tailored to the severe cold climate in Yulin, which could serve as a blueprint for similar cold regions around the world.

CO2 emissions from building operations have increased to their highest level, moving away from the Paris Agreement goal of below 2 °C. Zero carbon housing (ZCH) has been identified as a viable solution to realise carbon neutrality. However, ZCHs are barely recognised by the mainstream market due to the misconception of high up-front cost. This research aims to identify affordable solutions for ZCH by synergising building design, mechanical services, and renewable energy, and to balance capital cost and environmental benefits. An integrated framework of energy simulation, sensitivity analysis, and multi-objective optimisation is employed to achieve the goals. A representative house design is selected to demonstrate the proposed methodology, and a national energy rating scheme in Australia, NatHERS, is used for validation. The optimisation identified eight optimal solutions, resulting in a CO2 emission reduction between 1.894 tCO2 to 2.259 tCO2 with increased indoor comfort of 1.3%–2.6%. This research also finds that given the policy incentives, the actual incremental cost is marginal after the government rebate. This research addresses the major barriers of the high up-front cost associated with ZCH through an integrated approach. The research facilitates the paradigm shift in the mainstream market, promoting the development and market expansion of ZCH.

This study investigates the impact of vertical greenery systems (VGSs) applied to several typical wall configurations on indoor thermal conditions in a building module situated in the Mediterranean climate of Catania, Italy. By means of dynamic simulations in TRNSYS vers.18, the research compares the thermal behavior of walls made of either hollow clay blocks (Poroton) or lava stone blocks against a lightweight wall setup already in place at the University of Catania. The primary focus is on evaluating the VGSs’ capability of reducing peak inner surface temperatures and moderating heat flux fluctuations entering the building. The findings indicate that adding an outer vertical greenery layer to heavyweight walls can decrease the peak inner surface temperature by up to 1.0 °C compared to the same bare wall. However, the greenery’s positive impact is less pronounced than in the case of the lightweight wall. This research underscores the potential of green facades in enhancing the indoor thermal environment in buildings in regions with climates like the Mediterranean one, providing valuable insights for sustainable building design and urban planning.

Supply chilled water temperature (SCWT) is an important variable for the efficient and stable operation of heating, ventilation, and air conditioning (HVAC) systems. A precisely measured value ensured by the continuous reliability of the temperature sensor is essential for optimal control of an HVAC system because temperature sensor faults can affect the chiller operation and waste energy. Therefore, temperature sensor fault-detection strategies are imperative for maintaining a comfortable indoor thermal environment and ensuring the efficient and stable operation of HVAC systems. This study proposes a fault-detection method for an SCWT sensor using a virtual sensor based on a long short-term memory-autoencoder. The fault-detection performance is evaluated considering a case study under various sensor fault scenarios to evaluate changes in indoor thermal comfort and energy consumption after correcting sensor faults detected by the virtual sensor. The results verify excellent fault-detection performance in various fault scenarios (F-1 scores ranging from 0.9350 to 1.000). After correcting the SCWT fault, indoor thermal comfort is steadily maintained without additional energy consumption (indoor set-point temperature unmet hour reduced by a maximum of 105.7 hours, and energy consumption decreased by up to 1.8%). [ABSTRACT FROM AUTHOR]

The dry Mediterranean climate (BShs) within a warm semi-arid climate (BSh) is the zone in Europe with the most annual hours of sunlight, and it has a smaller annual temperature variation than most climates. This allows the greenhouse effect caused by windows to be used to heat dwellings in winter. Balcony frameless retractable glazing systems known as "glass curtain" systems offer the highest proportion of glass and maximum openness in the façade, allowing for maximum sunlight and ventilation. This work studies a glazed terrace with a "glass curtain" in a dwelling on the Spanish Mediterranean coastline. The objective is to quantitatively determine the enhancement of the thermal comfort and energy efficiency of a dwelling using "glass curtain" systems. The modification of several design parameters of the glazed terrace is also analysed. The novelty of this study lies in demonstrating that the use and optimised design of "glass curtain" systems allows us to obtain nearly zero-energy buildings (nZEBs) and thermally comfortable dwellings all year round. The research methods include a comparison of the current thermal performance of the dwelling with and without a "glass curtain" system via on-site measurements. The study also evaluates the influence of modifying design parameters using computer simulations. The results show that "glass curtain" systems increase the indoor temperatures inside the dwelling by about 4 °C in winter and reduce the annual indoor thermal oscillation from more than 16 °C to only 10 °C. Consequently, such systems reduce heating energy needs by almost 60%. Glazed terraces using the proposed design parameters show further improvement regarding thermal comfort and practically eliminate heating and cooling needs. [ABSTRACT FROM AUTHOR]

The ecological construction experience of traditional dwellings has been widely recognized. Hanzhong city belongs to the Hot Summer and Cold Winter zone, and the attic space is a common climate strategy in this area. The research takes a traditional dwelling in the region as an object in order to analyze the influence on the thermal environment of the attic. Firstly, we adopt field investigation and measurement to calculate the neutral temperature of 13.85 °C and 26.21 °C in winter and summer, respectively. It achieves the First-level comfortable zone, which ranges from 11.47 °C to 16.22 °C in winter and from 23.03 °C to 29.39 °C in summer. Then, comparative analysis reveals that the dwelling with attic space has a more comfortable and stable thermal environment than that without an attic through simulation. The indoor average operating temperature of dwelling with attics is 2.52 °C higher than that of a dwelling without attics in winter. On the contrary, the value decreases by 4.93 °C between those in summer. Finally, it shows that the attic space can increase the comfort duration by 995 h and 382 h, and reduce energy consumption by 1136.53kw and 566.43kw in winter and summer. Therefore, attic space adapts to the local climate and improves the indoor thermal environment significantly.

Rock-cut architecture is among the unique types of ancient architecture in Iran, which creates human living space by excavating the stone mass in the rocks. The rock-cut architecture benefits from utilization of the temperature of the groundmass in cold and hot weather by penetrating its heart. The World Heritage Site of rock-cut architecture in Meymand with more than 360 architectural units is considered as an evolved and appropriate example of such architecture in the semi-hot and dry foothill climate of Iran. The present study aims to determine indoor thermal comfort level of some buildings in the site as mentioned earlier to measure their fitness to climatic conditions of the area without energy consumption. To this aim, Predicted Mean Vote (PMV) index was determined for four selected buildings through the indoor bioclimatic monitoring, as well as calculating the level of the above-mentioned index during December–February and June–August.​ Then, the ASHRAE standard questionnaire was prepared to evaluate and compare the comfort sensation feedback of the occupants in the aforementioned buildings with indoor PMV calculation results. The results indicated that the average indoor PMV during the winter and summer equaled -2.17 and -1.07 with a cold and cool sensation, respectively, which is in line with those of the questionnaire in which most occupants reported a neutral and cold sensation during the winter and a cool one during the summer. In addition, calculation of the percentage of proximity to the comfort zone for indoor environment of the above-mentioned buildings showed they are closer to comfort by 22% and 36%, during the winter and summer, respectively Finally, the results indicated the rock-cut architectural buildings had provided conditions by applying the high thickness of their architectural layers, low heat exchange coefficient of the walls, and temperature of the groundmass, which they are in the comfort zone without energy consumption in summer and provide living conditions with minimal energy consumption in winter.

In hot-humid climates, particularly in sub-Saharan Africa (SSA), ambient temperatures and relative humidity are as high as 35 °C and 84%, respectively, requiring the use of mechanical cooling systems for indoor thermal comfort. Split-type vapor-compression air-conditioners (SVAC) are mainly used for space cooling in SSA and consume 60–80% of total energy consumption in commercial and public buildings. Appropriate control strategy of the indoor set-point temperature of SVAC can result in significant energy savings in these buildings. In this study, modeling and dynamic simulation have been conducted using EnergyPlus to predict the energy saving potential and indoor thermal comfort of buildings in hot-humid climates by controlling set-point temperature of the SVAC. In a case study, climatic data for Ghana, was used to predict the energy saving potential and indoor thermal comfort. The study results revealed that, to ensure indoor thermal comfort at high outdoor temperature condition of 35 °C, the least and optimum set-point temperatures of the SVAC should be 21 °C and 25 °C, respectively. On the other hand, for low outdoor temperature condition, the least and optimum set-point temperatures were 22 °C and 26 °C, respectively. Considering 1-star and 2-star rated SVACs which are dominantly used in Ghana, operating at 21–25 °C in the case of high outdoor conditions, and 22–26 °C for low outdoor conditions relative to the least temperatures resulted in energy savings of 8–33% and 12-44%, respectively.

The clothing color could always produce different human heat transfer and thermal sensation under solar radiation. And this issue has already been scrutinized by a few studies in outdoor environment. As the natural lighting is becoming common in buildings, e.g. the large curtain walls in high-rise buildings, the direct solar radiation could also affect the indoor occupants. Consequently, effects of the clothing color on the human body could not be ignored. Unfortunately, very limited studies have been reported in this field. In order to acquire the contribution of the clothing color to the heat transfer and thermal sensation of the indoor occupants, experimental study was conducted in this paper. Firstly, considering the non-uniformity of direct solar radiation on the indoor occupants, the equations that were used to calculate the solar heat gain of different body segments and the clothing surface temperature were revised, respectively. Thereafter, an experimental study was conducted in a climate chamber in winter. Participants wore cloth with different colors when exposed to different solar radiation intensities, during which the mean skin temperature, heat transfer, and subjective evaluations were acquired. Results showed that the dark clothing led to the reduced total heat loss by 4.52%, compared with that of the light clothing, at the solar radiation intensity of 200 W/m2. And the mean thermal sensation vote (TSV) under dark clothing was 0.65 higher than that under the light clothing. Meanwhile, at the solar radiation of 400 W/m2, the total heat loss under dark clothing was 14.17% lower than that under the light clothing, and the mean TSV under the dark clothing was found to be 0.25 higher that under light clothing condition. The results implied that wearing the dark clothing could benefit the improvement of the indoor human thermal comfort at low solar radiation in winter. These findings could provide a few useful references for studies on indoor thermal comfort under the solar radiation.

The heritage buildings of a country or region are frequently considered to be of value and significance to the current generation. This study investigates the winter indoor thermal comfort of heritage buildings in hot summer and cold winter zone of China. Field measurements and questionnaire surveys were used to conduct specific studies on the winter indoor thermal comfort of two typical traditional residential buildings (“Yinziwu” and “Diaojiaolou”) in the Yuan River basin heritage building area. The aim is to investigate the current status of building thermal comfort and provide a theoretical basis for promoting their sustainable development. The results show that 1) Indoor air temperatures in both types of buildings are significantly and positively correlated in winter, but both are below the human thermal comfort range. 2) Mean air temperatures measured in ''Yinziwu'' and ''Diaojiaolou'' are 8.8 °C and 9.4 °C, respectively, with neutral air temperatures of 11.1 °C and 13.8 °C. 3) Thermal sensation, thermal preference, and thermal comfort were significantly correlated in the two buildings, with ooccupants experiencing the coldest phase from 7:00–11:00 and the warmest phase from 15:00–19:00 daily. 4) ''Yinziwu'' occupants are more tolerant of the cold climate.

Densely built areas with poor thermal insulation suffer from high thermal environmental risks and generally consume high energy in summer. Determining the relationship between density and energy consumption is necessary, particularly when implementing urban heat island (UHI) countermeasures. This study evaluated the effects of density and UHI countermeasures on the energy consumption and indoor thermal comfort of a detached house in a typical densely built wooden house area in Yokohama City, Japan. Three densities and six countermeasures were considered. Annual hourly simulations based on the SCIENCE-Vent thermal environment simulation model yielded the following results: in densely built wooden house areas, the energy consumption and thermal discomfort increased with density. The green roof yielded the largest energy savings in the cooling and heating seasons, demonstrating the highest annual energy savings with 5.7%. Density had little impact on rooftop countermeasures, but the effect of the high-reflectance walls increased with density, and the reduction in annual energy consumption (air conditioning and lighting) is 2.6%, 3.0%, 3.6% in 37%, 47%, and 59% density cases, respectively. The impact of thermal countermeasures on indoor thermal comfort varied according to the thermal control mechanism. [ABSTRACT FROM AUTHOR]

Thermal bridges significantly influence the energy performance of buildings. However, their impact varies depending on the type of thermal bridge, climate conditions, construction methodologies, and geometric characteristics of the building. On the Spanish Mediterranean coast, buildings with large balconies are predominant. Nevertheless, the Spanish energy efficiency regulations do not adequately specify the thermal bridges at the junctions of balconies with facades, leading to a lack of consideration for their influence in the majority of architectural projects. The objective of this study is to qualitatively and quantitatively assess the impact of such thermal bridges on the energy efficiency of buildings in a dry Mediterranean climate (BShs) within a warm semi-arid climate (BSh). As a case study, the influence of this thermal bridge is analyzed in two residential buildings located on the Mediterranean coast of southeastern Spain. The study also examines the modification of various construction parameters of this thermal bridge and determines the optimal design parameters to reduce its thermal transmittance. The results demonstrate that the energy needs caused by thermal bridges account for approximately 40% of the total annual energy needs of the studied residential buildings. Balcony thermal bridges account for 25% to 40% of the energy needs caused by all thermal bridges. The lack of differentiation in Spanish standards between balcony–facade and facade–slab edge junctions causes an imprecision in calculations equivalent to 12% of the total annual energy needs of dwellings. The novelty of this research lies in highlighting that current regulations and calculation programs need improvement to better characterize balcony thermal bridges and enhance the accuracy of building energy efficiency calculations.

Gaotai dwellings are the most important representative of dwellings in Xinjiang. It is an important evidence for studying the living customs and architectural features of ethnic minorities. The building enclosure type (BET) and building orientation (BO) are important factors that influence the indoor thermal comfort of the courtyard building. In this research, 20 test scenarios are simulated through field investigation and virtual simulation integrated in the software to grasp the influence of BET and BO on indoor thermal environment. The conclusions are as follows: 1. The higher the degree of building enclosure, the higher the number of comfort hours and the better the comfort. 2. Each BET has its suitable orientation. The best orientation of “T” type is east, the best orientation of “I” type and “L” type is north, and the best orientation of “C” type and “O” type is south. 3. When the optimal BET is combined with its corresponding optimal orientation of the main room, the indoor thermal comfort will be greatly increased (comfort hours in winter and summer will increase by 62.9% and 37.1%).The conclusion of this study can provide flexible design ideas for courtyard buildings to improve the thermal comfort in Kashi.

As urbanisation intensifies, an increased proportion of human activities is observed to be conducted indoors, amplifying the imperative of a superior indoor living environment. Among the various facets influencing indoor environmental quality, thermal comfort emerges as a pivotal factor influencing both physical and mental well-being. While predominant research methodologies predominantly employ empirical evaluations, the nuanced impacts of interior architectural structures on airflow and temperature distribution often remain unaddressed. Furthermore, rigorous simulations based on fluid dynamics are frequently absent from these assessments. In this study, the interplay of heat transfer and ventilation within interior architecture is meticulously examined. A novel research framework is introduced, encapsulating evaluations of human thermal comfort in ventilated interiors, intricate indoor airflow simulations predicated on fluid dynamics, and the pioneering design strategies for optimised hollow and ventilated architectural interior wall systems. [ABSTRACT FROM AUTHOR]

The energy-supply crisis, aggravated by the war in Ukraine, has prompted EU governments to approve urgent energy-saving measures. The new Spanish energy-saving standard aims to reduce energy consumption by changing the regulatory limits for indoor hygrothermal conditions in buildings. This regulation has provoked a great social debate about its real effectiveness and its impact on user comfort. This work explores the hygrothermal performance of an office building in southeastern Spain. The objective of this research is to determine qualitatively and quantitatively how the new energy-saving standard in Spain influences energy efficiency and indoor thermal comfort, by considering the characteristics of the dry Mediterranean climate (BShs) within a warm semi-arid climate (BSh). The scientific novelty of the study is to demonstrate that the new Spanish standard not only reduces energy costs but also makes the indoor comfort of buildings much worse; for this reason, an improvement in the standard is also proposed. The study methodology consists of a comparative study between the thermal performance, thermal comfort, and energy demand of the building, considering both the new and previous standards' requirements. It also includes the evaluation of a proposal to improve the current standard. The results showed that the new energy-saving standard reduced energy consumption by 21.78% in comparison to former standards, but the new comfort ranges were not acceptable for 60% of the users. The proposed improvement does achieve acceptable comfort for most users (75%) and an additional reduction in energy demand of 48.76% compared to current standard. We conclude that the thermal comfort requirements of the current energy standard should be modified to better adapt the design criteria to the dry Mediterranean climate. [ABSTRACT FROM AUTHOR]

The existing building stock is globally responsible for 17.5% of greenhouse gas emissions due to their operation to achieve occupant satisfaction, thus requiring a vast intervention. However, reducing building stock emissions and optimizing building energy performance cannot be considered independently by the users' well-being. The thermal comfort conditions and their monitoring represent a central issue that could optimize building energy usage while achieving good indoor environmental conditions. This document describes the first findings of ongoing research focused on the development of a building monitoring system, based on the integration of Building Information Modeling tools and sensor technology through Dynamo Visual Programming. Starting from the development of an Asset Information Model, which represents the virtual replica of a building that currently hosts the administrative offices of the municipality of Cagliari, the first step presented in this contribution shows a thermal comfort monitoring system, scalable and modular, that allows effective gathering and elaboration of data about comfort levels in each of the building's rooms. The system proves to be a helpful support for facility managers to control building thermal comfort conditions and HVAC systems to assure their best operative status or plan suitable interventions to achieve it. [ABSTRACT FROM AUTHOR]

With global warming, the climate is becoming hotter, even at higher latitudes. In order to clarify the thermal environment and thermal comfort level of rural residents at higher latitudes in summer, a field survey on thermal comfort was conducted in Suibin Town, China. The results show the following: (1) The correlation between the operative temperature and the mean thermal sensation score is stronger than that between the operative temperature and the thermal sensation score. Moreover, the applicability of the thermal comfort evaluation index of the operative temperature in severely cold areas was verified. The linear regression method showed that the neutral temperature is 25.1 °C and the thermal acceptable range is 22.5–27.6 °C. (2) There is a strong correlation between thermal sensation and thermal acceptability. (3) The preferred temperature in summer is 25.3 °C. Moreover, rural residents prefer cooler indoor temperatures in summer. (4) The clothing insulation of rural residents decreases with an increase in the indoor operative temperature. (5) Rural residents' acceptance of the indoor temperature in summer is influenced by the economy, psychology, adaptive behaviors, etc. Moreover, rural residents expect cooler indoor temperatures in summer and will adapt to the thermal environment via low-cost adaptive behaviors. [ABSTRACT FROM AUTHOR]

Energy used in buildings is mainly attributed to provide the desired thermal comfort, which could result in an increase in carbon emission and, in turn, lead to further environmental degradation. A Building-Integrated Photovoltaic Double-Skin Façade (BIPV-DSF) is a promising way to maintain indoor thermal comfort, obtained with low environmental impact and energy consumption. The appropriate design of BIPV-DSFs can maximise indoor thermal comfort and energy efficiency for buildings. This paper presents optimal BIPV-DSF design solutions, which are dedicated to offering comfortable and energy-efficient buildings, through optimisation of the most important design parameters of a BIPV-DSF under three different climate conditions in Australia. The results illustrate how thermal transmittance (U-value) and solar heat gain coefficient (SHGC) of windows of the BIPV-DSF, as the most important design parameters, were optimised for application in the context of different climates, operation modes, and orientations. The paper contributes to the matters concerning the integrated effect of BIPV-DSFs on thermal comfort and energy performance in buildings. [ABSTRACT FROM AUTHOR]

Occupant comfort in buildings is one of the most crucial considerations in designing a building. Accordingly, there is a growing interest in this area. Aspects of comfort include thermal comfort, visual comfort, acoustic comfort, and indoor air quality (IAQ) satisfaction. The objective of this state-of-the-art review was to provide a comprehensive, explicit, and up-to-date literature review on occupant comfort in buildings, since this issue has a great impact on the lifestyle, health, and productivity of occupants. A meta-synthesis method was also used for an analytical-interpretive review of previous studies. In this research, scientific research studies related to the subject of indoor occupant comfort in the period 2002–2022 were reviewed. Previous reviews have often covered the fundamental concepts and principles related to indoor occupant comfort. Although innumerable studies have focused on thermal comfort, other aspects of occupant comfort have not been considered. The review is analyzed and discussed in reference to type of study, case study geographical locations and climate zones, case study building types, decision-making models, assessment criteria, data-collection tools, and data analysis strategies. Finally, future research recommendations are presented. Through the review, we find that the comfort models used in research are mostly based on comfort perception votes collected from experimental studies, which may not reflect the preferences of users well. In addition, only the influence of environmental factors on the models has been investigated, and other personal factors have been ignored. This study presents a useful guide for researchers to determine their outlines for future research in this field. [ABSTRACT FROM AUTHOR]

Supply chilled water temperature (SCWT) is an important variable for the efficient and stable operation of heating, ventilation, and air conditioning (HVAC) systems. A precisely measured value ensured by the continuous reliability of the temperature sensor is essential for optimal control of an HVAC system because temperature sensor faults can affect the chiller operation and waste energy. Therefore, temperature sensor fault-detection strategies are imperative for maintaining a comfortable indoor thermal environment and ensuring the efficient and stable operation of HVAC systems. This study proposes a fault-detection method for an SCWT sensor using a virtual sensor based on a long short-term memory-autoencoder. The fault-detection performance is evaluated considering a case study under various sensor fault scenarios to evaluate changes in indoor thermal comfort and energy consumption after correcting sensor faults detected by the virtual sensor. The results verify excellent fault-detection performance in various fault scenarios (F-1 scores ranging from 0.9350 to 1.000). After correcting the SCWT fault, indoor thermal comfort is steadily maintained without additional energy consumption (indoor set-point temperature unmet hour reduced by a maximum of 105.7 hours, and energy consumption decreased by up to 1.8%).

The dry Mediterranean climate (BShs) within a warm semi-arid climate (BSh) is the zone in Europe with the most annual hours of sunlight, and it has a smaller annual temperature variation than most climates. This allows the greenhouse effect caused by windows to be used to heat dwellings in winter. Balcony frameless retractable glazing systems known as “glass curtain” systems offer the highest proportion of glass and maximum openness in the façade, allowing for maximum sunlight and ventilation. This work studies a glazed terrace with a “glass curtain” in a dwelling on the Spanish Mediterranean coastline. The objective is to quantitatively determine the enhancement of the thermal comfort and energy efficiency of a dwelling using “glass curtain” systems. The modification of several design parameters of the glazed terrace is also analysed. The novelty of this study lies in demonstrating that the use and optimised design of “glass curtain” systems allows us to obtain nearly zero-energy buildings (nZEBs) and thermally comfortable dwellings all year round. The research methods include a comparison of the current thermal performance of the dwelling with and without a “glass curtain” system via on-site measurements. The study also evaluates the influence of modifying design parameters using computer simulations. The results show that “glass curtain” systems increase the indoor temperatures inside the dwelling by about 4 °C in winter and reduce the annual indoor thermal oscillation from more than 16 °C to only 10 °C. Consequently, such systems reduce heating energy needs by almost 60%. Glazed terraces using the proposed design parameters show further improvement regarding thermal comfort and practically eliminate heating and cooling needs.

The conditioning of living and working spaces in the building sector consumes a significant amount of energy. Among the natural ventilation techniques that rely on renewable energy sources such as geothermal and wind, wind towers and earth to air heat exchangers (EAHEs) hold prominence. This research paper presents a series of experiments conducted in the arid region of Bechar, Algeria, to investigate the effectiveness of combined natural ventilation systems employing wind towers and EAHEs. The test chamber, constructed from plywood, and the tower, along with the buried polyvinyl chloride (PVC) pipe EAHE at a depth of 150 cm in sandy-loam soil, constitute a completely natural system with zero energy consumption. Two scenarios were examined: one with closed windows and the other with open windows measuring 40 × 40 cm2. The results indicate a noteworthy improvement in thermal comfort within the chamber, with an increase from 18.75% for the closed window system to 50% when the window is open. By employing a completely natural system without energy consumption, it becomes possible to fulfill 50% of the thermal comfort requirements during both summer and winter seasons. Consequently, this approach reduces at least half of the energy demands in a region that experiences six months of discomfort. [ABSTRACT FROM AUTHOR]

Solar heat gain and natural ventilation cooling of the indoor environment in buildings are highly influenced by the shading and openable area of windows. In addition to the ambient condition, the Heating, ventilation and air conditioning (HVAC) system's mode of use can affect the windows' performance, especially when multiple modes are used in combination (mixed-mode). Although many studies have investigated the mixed-mode application, their conditions for starting/shutting down HVAC equipment and controlling window ventilation are inconsistent with the relevant codes. Here, we propose a mixed-mode operation that resolves the gap between the air conditioning operation temperature and the adaptive comfort upper temperature. It investigates residential buildings' indoor thermal environment and energy efficiency by combining the effective ventilation opening area ratio (REV) and shading design. Simulation results show that our mixed-mode can reduce the indoor overheating hours by about 50% and the building's energy consumption by about 50%. We thereby conclude that the openable area of exterior windows in residential buildings in Chongqing should not be less than 10% of the room's floor axis area where the exterior windows are located. In general, our study expands the existing knowledge of passive energy-saving measures and provides a method for further research on building energy design in hot summer and cold winter regions. [ABSTRACT FROM AUTHOR]

This paper aims to identify the most suitable construction materials in terms of building's energy performance and indoor thermal comfort for a hot and semi-arid climate. An experimental validated TRNSYS-based numerical model was set to carry out dynamic simulations for the energy performance assessment of four similar houses built with different materials, namely Cinder Blocks, Reinforced Concrete, Fired Bricks, or Rammed Earth. The results show that the rammed earth house had the best thermal performance thanks to its high thermal mass, which helped maintain a stable indoor air temperature for optimal thermal comfort. Adding shading and night natural ventilation contributed to the further improvement of the rammed earth house's thermal performance. Indeed, the annual heating/cooling load of the rammed earth house was 23%, 11% and 3% lower than the reinforced concrete, cinder blocks and fired bricks houses, respectively. These thermal load differences were much more reduced to 51%, 24% and 5%, respectively, after adding the shading and night natural ventilation techniques. Furthermore, this study evaluated the use of low embodied energy and weak carbon footprint construction materials to achieve a good building's thermal performance and acceptable indoor thermal comfort. [ABSTRACT FROM AUTHOR]

This paper summarizes the results of a comprehensive analysis to investigate the performance of both thermal comfort-based and temperature-based controls for schools in harsh hot climates of Saudi Arabia. The analysis considers the impact of building envelope characteristics including thermal insulation level of exterior walls and air leakage rate on the ability of both control options to maintain indoor thermal comfort while minimizing cooling energy consumption. The analysis utilizes a calibrated energy model for an existing Saudi school with monitored energy consumption data. The analysis results indicated that the thermal comfort-based control is able to maintain the predicted percentage of dissatisfied (PPD) value at 5% throughout the year for any combination of the exterior wall's R -value and air infiltration rate unlike the case of the temperature-based controls that do not maintain acceptable indoor thermal comfort conditions. However, the thermal comfort-based controls consume more cooling energy than the temperature-based controls. The analysis also revealed that the difference between the annual cooling energy of the PMV-based control and the temperature-based controls increases almost linearly with the cooling degree days of the site where the school is located. The analysis results indicate that acceptable indoor thermal comfort levels can be achieved using temperature-based controls when optimal temperature set points are used. [ABSTRACT FROM AUTHOR]

Developing countries encounter challenges in adopting advanced roof systems due to the complexities associated with implementing advanced materials and techniques. This study introduces an advanced four-stage approach as a combined technique, aiming to formulate an innovative affordable cool roof application that addresses the limitations of contemporary cool roof systems. The first stage involves reviewing Cool Roof Materials (CRMs) by classifying them into three categories: traditional, modern, and advanced roofing systems, with subclasses for each category. In the second stage, Affordable Green Materials (AGMs) are reviewed to suggest alternatives aligned with the study objectives. The third stage focuses on monitoring performance methods to evaluate applicability, while the fourth stage assesses the potential transformation of these alternatives into future fabrication processes. The study suggested a natural composite sandwich panel that incorporates three main layers, with multiple potential materials alternatives for each layer. The main panel consists of a reflective coating layer, a natural insulation composite layer, and a substrate layer. It could result in a significant 44 % decrease in surface temperature, with potential energy savings reaching up to 70 % and reductions in cooling loads of up to 51 %. It forms the basis of a new affordable cooling roof technology that effectively addresses the complexity of contemporary systems, potentially resulting in significant advances in passive cooling systems. The review also identifies areas requiring further research. Ultimately, this combination of environmentally friendly solutions could pave the way for holistic innovation in sustainable building design, contributing substantially to global climate objectives and energy-saving targets. [Display omitted] • A novel four stage approach is introduced to optimize cool roof assessment. • The research addressed the potential materials used as a cool roof component. • The study systematically reviewed an overall 142 articles. • Results highlighted the potential of bio-composite insulation panels. [ABSTRACT FROM AUTHOR]

• Liquid-desiccant air-conditioning system applied to a high-latent-load building. • A vapor compression cooling system is chosen as a reference system for comparison. • Onsite indoor thermal comfort and energy performance of both systems are analyzed. • Proposed system saves 92.4% of energy, achieving thermal comfort in rainy weather. • Proposed system saves 12.1% of energy, achieving thermal comfort in summer weather. Indoor humidity control is increasingly important because indoor sensible heat ratio decreases to reduce building energy consumption. However, reference vapor compression cooling systems exhibit energy inefficiency and limitations in maintaining indoor thermal comfort. Therefore, this study proposes an alternative heat-pump-driven liquid-desiccant air-conditioning system, independently controlling air temperature and humidity. The reference and proposed systems are applied to a high-latent-load building to investigate their onsite indoor thermal comfort and energy performance empirically and simultaneously under various outdoor summer conditions. The reference system exhibits a thermal comfort satisfaction ratio of 97% only under limited hot and dry weather. Conversely, the thermal comfort satisfaction ratio sharply drops to 2% or less under humid weather. The proposed system consistently achieves a high thermal comfort satisfaction ratio exceeding 90% under various outdoor summer conditions. In empirical comparisons, the proposed system can maintain a thermally comfortable room for an hour while achieving energy savings exceeding 92.4% and 12.1% under warm and humid (rainy season) and hot and humid outdoor conditions, respectively. The proposed system is concluded to consistently maintain indoor thermal comfort while using energy efficiently, demonstrating its widespread applicability for general high-latent-load buildings characterized by low indoor sensible heat ratio values of 0.56 on average. [ABSTRACT FROM AUTHOR]