Indoor Thermal Conditions Research Articles

EVALUATION OF VENTILATED CAVITY WALL DESIGN FOR PASSIVE COOLING OF INDOOR SPACES

The function of building facades includes the regulation of solar-radiated heat. It also includes regulating the ranges of heat transfer from the exterior to the interior of a building. The primary functions of building facades promote energy conservation, hence making the art of façade design a vital energy-efficient option in sustainable building. The concept of a ventilated cavity wall is presented in this paper as an option that functions as a barrier for trapping excessive heat radiated naturally through building envelopes, while at the same time utilizing ventilation of the cavity space in its double layer to control the heated façade through aeration of the cavity space. A review of modern active multi-skin façade systems adopted by designers reveals the climate-responsive ideas associated with double-skin facade designs. This study emphasizes the function of the ventilated cavity wall as a climate-responsive system that passively enables the cooling of indoor spaces. For this purpose, a study of a sample of this design was conducted to ascertain the thermal control properties. The study includes an experimental evaluation and thermal simulation of the sample model using the Phoenix-VR application. The results of the interior air temperature and internal façade cavity conditions reveal that this façade system may substantially reduce the thermal effect on building walls. This is seen in the significant decrease of the indoor room temperature by up to 5oC compared to the cavity air temperature. The result provides a good premise for designers to adopt the principles of the ventilated cavity wall system in building designs. For application, residential homes that adopt the ventilated cavity wall option may further improve indoor thermal conditions through whole building orientation or by indoor space orientation. The indoor spatial orientation if properly managed during the building design process may add to the energy conservation potential

A Critical Review of Overheating Risk Assessment Criteria in International and National Regulations—Gaps and Suggestions for Improvements

The escalating environmental threat of indoor overheating, exacerbated by global climate change, urbanisation, and population growth, poses a severe risk to public health worldwide, specifically to those regions which are exposed to extreme heat events, such as Australia. This study delves into the critical issue of overheating within residential buildings, examining the existing state of knowledge on overheating criteria and reviewing overheating guidelines embedded in (a) international standards and (b) national building codes. Each regulatory document is analysed based on its underlying thermal comfort model, metric, and indices. The advantages and limitations of each document are practically discussed and for each legislative document and standard, and the quantitative measures have been reviewed, analysed, and summarised. The findings illuminate a global reliance on simplistic indices, such as indoor air temperature and operative temperature, in the existing regulatory documents. However, other critical environmental parameters, such as relative humidity, indoor air velocity, and physiological parameters including metabolic heat production and clothing insulation, are often not included. The absence of mandatory regulations for overheating criteria in residential buildings in some countries, such as in Australian homes, prompts the call for a holistic approach based on a thermal index inclusive of relevant environmental and physiological parameters to quantify heat stress exposure based on human thermal regulation. Gaps and limitations within existing guidelines are identified, and recommendations are proposed to strengthen the regulatory framework for overheating risk assessment in residential buildings. The findings hold significance for policymakers, building energy assessors, architects, and public health professionals, providing direction for the improvement of existing, and development of new, guidelines that aim to enhance indoor thermal condition and population health while ensuring energy efficiency and sustainability in the building stock.

A Model of Indoor Thermal Condition based on Traditional Acehnese Houses using Artificial Neural Network

This paper examines the thermal condition aspects of traditional Acehnese houses (Rumoh Aceh) in Indonesia. This study highlights the importance of considering traditional architecture in achieving comfortable living conditions. Through the integration of cultural values, architectural design, and environmental factors, this research evaluates the prediction of thermal conditions within Rumoh Aceh based on building orientation and location, serving as guidelines for architects in designing buildings in the Aceh region. The study employs an ANN (Artificial Neural Network) algorithm to predict thermal condition parameters including indoor: temperature, humidity, and wind speed. The sample data used to train the ANN model consists of thermal data from five different rooms and meteorological data. The ANN model is employed to predict the thermal conditions in the Rumoh Aceh building based on its orientation and location. In this study, two models were developed, namely MODEL_01, for predicting indoor temperature and humidity, and MODEL_02, for predicting indoor wind speed. In MODEL_01, the error tolerance level obtained is ±1.05, and in MODEL_02, it is ±0.03. The prediction results based on the building orientation show the lowest average indoor temperature value of 29.19°C, occurring at an angle of 292.19°. Furthermore, the lowest average indoor humidity value is 74.57%, which also occurs at an angle of 292.19°. However, for indoor wind speed, the angle of 260° records the lowest average value of 0.125 m/s, while the highest average value is observed at 292.19°, at 0.132 m/s. The prediction results based on the building’s location show the lowest average temperature value, which is 29.44°C in the Aceh Besar region. Furthermore, the lowest average humidity value is 75.11% in the North Aceh region. Meanwhile, the highest average wind speed value is 0.174 m/s in the Sabang region. This study reveals that at the orientation angle of 292.19° (the qibla direction), it produces optimal thermal conditions in terms of temperature and humidity with low wind speed. Other findings indicate that the Aceh Besar, North Aceh, and Sabang regions have optimal thermal conditions based on temperature, humidity, and wind speed.

PERANCANGAN SMART VERTICAL GARDEN SEBAGAI STRATEGI MENINGKATKAN RUANG HIJAU DAN KENYAMANAN TERMAL

Balikpapan, located in East Kalimantan Province, Indonesia, is experiencing rapid growth accompanied by increasingly complex environmental challenges, including the effects of climate change. Data shows a rise in air temperature, impacting not only the outdoor environment but also the indoor thermal conditions of public buildings such as offices, shopping centers, and educational institutions. At Institut Teknologi Kalimantan (ITK), the increasing demand for air conditioning systems reflects the direct impact of global temperature rise, resulting in heightened energy use and greenhouse gas emissions. In response to these issues, this research explores the design and implementation of smart vertical gardens as an innovative solution to enhance thermal comfort and energy efficiency. The smart vertical garden utilizes shading plants, sensor technology, and automation to reduce a building’s carbon footprint while improving thermal comfort. Building B at ITK is chosen as the case study due to its function as a hub of academic activities, making it a strategic location for implementing this green technology. The research adopts a comprehensive approach, including literature review, empirical data collection, thermal analysis, simulation, and design. The findings demonstrate the effectiveness of the smart vertical garden in reducing cooling energy demand, improving thermal comfort, and promoting campus greening. The implementation of this technology has the potential to serve as a sustainability model for public buildings. The results of this study provide valuable insights for academics, practitioners, and policymakers in developing green strategies and advancing sustainable development.

Study on indoor thermal conditions of a triple envelope incorporated with PCM in the passive solar building under different climates by analytical method

Clarifying the thermal mechanism of buildings provides a basis for the scientific design and optimization of envelopes. This study explored the mechanism of outdoor thermal disturbances, thermal storage materials, the building noumenon and internal heat sources (IHS) affecting indoor thermal conditions (ITC) by analytical method. The triple envelope incorporated with phase change material (EIPCM) form of “outer insulation layer + structural layer + inner PCM layer” was determined and theoretically derived a predictive model of the indoor thermal conditions (PMITC) to evaluate thermal comfort in five representative regions of northwest China. Following that analyzed the significance of the influencing factors on ITC employing linear regression. The results illustrated that ITC was mainly affected by the coupling of four aspects factors. More in detail, solar radiation entering the room exploited the most prominent effect on the increase in average indoor temperature. PCM layer only affected the temperature amplitude but not the average indoor temperature. The sensible heat storage of the structural layer had a weaker effect on ITC than the PCM layer. The lowest temperatures in Yinchuan and Xi’an were both above 16 °C, while Urumqi had a higher temperature fluctuation of 2.1 °C and an average indoor temperature of 6.32 °C lower than Xi’an. Based on the estimate of ITC and degree hours (DH), the application effects of PCM in buildings in five regions can be summarized as complete thermal comfort (Yinchuan and Xi’an), partial thermal comfort (Lanzhou and Xining) and complete thermal discomfort (Urumqi). For the different factors that affected ITC, the window-to-wall ratio (WWR) had the highest coefficient of determination exceeding 93 % and the building dimension performed the lowest around 26 %.

The Impact of Residential Building Insulation Standards on Indoor Thermal Environments and Heat-Related Illness Risks During Heatwaves: A Case Study in Korea

This study investigates the impact of building insulation standards on indoor thermal environments and the risk of heat-related illnesses during heatwaves in South Korea. Indoor temperatures were measured in residential buildings located in Chuncheon and Gwangju during the 2022 heatwave, with outdoor temperature data sourced from the Korea Meteorological Administration. Probability distribution fitting was used to estimate the likelihood of indoor temperatures exceeding the critical threshold of 27 °C. Additionally, a linear regression analysis was conducted to examine the relationship between the probability of exceeding the threshold and heat-related illness data from 2017 to 2023 provided by the Korea Disease Control and Prevention Agency. The findings reveal significant variations in indoor thermal conditions during heatwaves, influenced by factors such as building type, year of construction, and climate region, which affect the thermal insulation performance. Buildings with a lower thermal insulation performance were associated with higher indoor temperatures, increasing the likelihood of exceeding the critical threshold and contributing to a higher incidence of heat-related illnesses, particularly in provincial non-metropolitan areas. These results underscore the need for region-specific building insulation standards that address both winter energy efficiency and summer heatwave resilience. Enhancing thermal insulation in vulnerable regions could significantly reduce the risk of heat-related illnesses and improve public health resilience to extreme heat events.

Cooling Period Strategies in an Intermittent Usage Building: A Case Study of a Mosque in the Tropical Climate of Malaysia

Mosques are used five times a day according to the prayer schedule, which follows the sun's position. Indoor thermal conditions in air-conditioned mosques are maintained with a cooling time pattern that follows prayer times. Therefore, an effective air conditioning operating strategy is needed for energy efficiency. This study aims to investigate the effect of air conditioning intermittent operation time strategies on the energy usage of a mosque. It involves reducing the cooling period before prayer time and swapping active air conditioning periods from pre-prayer calls to post-prayer in the base case. Field measurements in Universiti Teknologi Malaysia – Kuala Lumpur (UTMKL) mosque and simulation using DesignBuilder software were conducted to predict annual specific energy consumption. The results indicate a reduction in specific energy consumption of 5% by operating the air conditioning 10 minutes before the call to prayer. Shifting the pre-prayer call-post prayer cooling period results in an insignificant reduction in energy consumption of 0.3-0.6%; however, it can accommodate extended periods of comfortable conditions for people who perform prayers outside of congregational prayers on time. Furthermore, the results indicate that the cooling period after the prayer time affects the cooling load of the following prayer. This study provides information for architects, engineers, and other stakeholders towards improving energy consumption in religious buildings with intermittent occupancy.

Research on assessing and enhancing indoor thermal and air conditions within typical elementary school classrooms in southern China

The thermal design of buildings in hot summer and cold winter regions must meet the requirements of thermal insulation in summer and heat preservation in winter. As a vital component of national compulsory education, primary schools must create a good indoor thermal environment for classrooms, which is particularly important for students. Due to the lack of construction standards and limited research on Chinese regions with hot summers and cold winters, policymakers have no comprehensive and efficient approach to creating optimal indoor thermal conditions in primary school classrooms. Therefore, based on the climate conditions of hot summer and cold winter areas, this study conducted field surveys in primary and secondary schools in hot summer and cold winter areas, summarized and analyzed the current situation of the surveyed classrooms and users' subjective evaluation of the indoor thermal environment of classrooms, and summarized the current hot summer and cold winter conditions. Problems in classrooms in primary and secondary schools in the region are clarified, and the research direction of construction strategies is clarified. The study found that most of the school hours in summer and winter were in a poor indoor thermal environment without refrigeration equipment. This study adjusted the school leaving time to 17:20 in summer and 17:00 in winter by adjusting the school leaving time to reduce the time of adverse thermal environment.

Investigating the Effects of PCM-Integrated Walls on Thermal Performance for UK Residential Buildings of Different Typologies

Phase change materials (PCMs) can improve the thermal performance of building facades. The integration position of a PCM in the facades is influenced by multiple factors including the material properties of the PCM, building types, and the internal and external conditions of a building. However, this has not been a focus within the UK dwelling stock, where many dwellings are not thermally protected. This paper, therefore, presents a numerical study with the aid of building simulation that comparatively analysed the thermal performance between four typical UK dwelling types (semi-detached house, terraced house, detached house, and apartment) situated in North East England. The PCM was implemented into the external wall of the dwellings with the positions altered to determine the most effective position. It was determined that the PCM positioned internally was the most effective for all the dwelling types. These results demonstrated that the PCM being implemented in the apartment, semi-detached, and terraced houses had only marginal heat loss reductions (by 8%, 14%, and 8%, respectively) in comparison with that of the detached house (by 30%). It was also found that the large external wall area of the detached house acted as significant thermal energy storage, which was capable of offsetting heat transmission and stabilising indoor thermal conditions. In summary, this paper contributes to the matters concerning the effect of PCMs on indoor thermal performance in dwellings of different typologies in the UK.

Assessing the Impact of Vertical Greenery Systems on the Thermal Performance of Walls in Mediterranean Climates

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.

Experimental evaluation of subjective thermal perceptions for different local window screenings

In tropical climate, restricting convective gain while allowing cross ventilation creates paradoxical difficulty regarding indoor thermal comfort. Changing global climate gives new dimensions to the scenario results in subsequent pressure on increasing energy demand towards thermal comfort. Passive techniques can be a good way to dealt with the problem. However, occupants’ thermal perception may vary from person to person for a definite indoor environmental setup. Perception of subjective thermal comfort is crucial for human health and wellbeing which in turns effects performance. In the current study evaluation of subjective thermal performance regarding improved indoor thermal comfort has been studied for three different local window screening: i) plastic bottle with its wider face towards wind direction, ii) plastic bottle with its narrower face towards wind direction and iii) perforated bamboo screen. Six subjects: four female and two male (ages between 22-24), have been investigated for 30mins. in an experimental simulation chamber for three consecutive days. Questionnaire regarding thermal sensation and perception has been prepared to collect subjective response at 10mins. interval. From the experiment it is seen that subjective responses varies for different window screenings as well as for a specific indoor thermal condition created with definite screening. Subjects find the indoor environment comfortable for screening with plastic bottle with its wider face towards wind direction compared to other two. Bamboo screening has comparatively better performance than the screening plastic bottle with its narrower face towards wind direction. The current analysis only considers the thermal sensation of the subject and further extension of study considering factors like the subject's site-specific thermal sensation and other psychological effects can contribute towards improving indoor thermal comfort in tropics towards human health and wellbeing.

Improvement of thermal environment in the outdoor atrium by employing the spray system

Outdoor atriums have recently been applied with increasing frequency for natural illumination, but they produce a harsh thermal environment easily in summer. Moreover, overheating of the outdoor atrium necessitates air-conditioning to moderate indoor thermal comfort. Simultaneously, the substantial heat emissions from air-conditioning outdoor units worsen the outdoor thermal environment, creating a vicious cycle. Traditional passive evaporative methods involving water and greenery, while capable of regulating the thermal environment, suffer from low evaporative efficiency and pose significant challenges. To improve thermal environment in outdoor atriums, the spray system was employed due to its high cooling efficiency, especially in open or semi-open spaces. In this study, a comparative experiment was conducted to evaluate the effectiveness of using a spray system for evaporative cooling in open outdoor spaces. Furthermore, employing high-efficiency evaporative cooling through spraying to disrupt the vicious cycle of indoor and outdoor thermal environments. The dual goals include regulating indoor and outdoor thermal conditions while also mitigating the local heat island effect. Temperature and humidity distribution within the atrium and adjacent hallways were monitored, along with the impact on air-conditioning operation consumption in neighboring offices. Results showed that the spray system significantly improved the thermal environment in the outdoor atrium, reducing the average and peak air temperatures by 0.94–2.83 °C and 2.92–5.21 °C, respectively. It also resulted in a drop in the average temperature by 0.56–1.62 °C and the peak temperature by 2.31–3.25 °C in adjacent hallways. This effectively eased the issue of overheating in these areas while raising the comfort level in adjacent office spaces. The predicted mean vote decreased from 1.46 to 0.87, indicating a significant improvement in thermal environment in neighboring offices. Furthermore, the daily energy consumption was reduced by 10.6–12.4% in neighboring offices. This study provided the valuable guidance for improving thermal environments within outdoor atrium.

A multi-objective approach to optimizing the geometry and envelope of rural dwellings for energy demand, thermal comfort, and daylight in cold regions of China: A case study of Shandong province

Rural dwellings in China’s cold regions face significant challenges related to energy consumption, thermal comfort, and daylight, with a projected substantial increase in energy demand in the future. Scientifically optimized design during the early planning stages can significantly enhance indoor thermal and daylight conditions, effectively reducing energy consumption. This study focuses on Shandong Province to comprehensively analyze the optimization of geometry and envelope design of rural dwellings in China’s cold regions. It employs a multi-objective optimization method, integrating genetic algorithms with dynamic energy simulations, to minimize total energy demand while ensuring thermal comfort and sufficient daylight. Utilizing the Octopus plugin in Grasshopper, in conjunction with EnergyPlus, Ladybug, and Honeybee, this research optimizes and analyzes the impact of various design variables on energy consumption, thermal comfort and daylight, including room depth, window-to-wall ratio in different orientations, thermal performance of the envelope, and related glass material parameters. The results indicate that the selected variables have significant energy-saving potential. Compared to the case study building, the optimized solutions can reduce total energy demand by over 62.41%, with the highest savings rate reaching 88.75%. This study emphasizes the importance of integrated design and optimization strategies in enhancing the sustainability of rural dwellings. It proposes both cost-free and cost-included optimization schemes: the former maximizes the energy-saving, thermal comfort and daylight potential of the selected variables, while the latter is more practically feasible considering the economic constraints of rural areas. The proposed optimization schemes provide multiple reference solutions and theoretical foundations for users of rural dwellings in China’s cold regions.

Geopolymer-based insulated wall incorporating construction and demolition waste: Experimental assessment of thermo-physical behavior

The benefit of the application of geopolymers in the building sector is nowadays undisputed. In addition to good structural characteristics, these are characterized by interesting thermophysical properties, obtained through a production process, that reduces CO2 emissions and could incorporate recycled material, thus responding to environmental sustainability. However, it is noted the lack of studies regarding the in-field thermal performance. Thus, the aim of the present study is to investigate the thermal performance, under real conditions, of an innovative geopolymer-based insulated wall. It incorporates over 70% of net weight of Construction and Demolition Waste materials. The wall is conceived within the European project called “Green INSTRUCT” aimed to realize modular prefabricated building elements, for retrofitting and new construction of buildings. Two wall prototypes are analysed, which differ for the type of lightweight aggregate of geopolymer matrix, 3% by weight: expanded polystyrene or extruded polystyrene. The study refers to almost one year of continuous monitoring within a full-scale test room located in southern Italy. The method developed consists of 5 different phases and it involves also a normative-insulated reference wall. The results show higher insulation level of the proposed wall package, with a reduction of the heat flux of about 66% and more stable indoor thermal conditions, compared to the reference wall. Also the inertial properties are satisfactory, showing an experimental decrement factor equal to 0.05 and a time-shift of decrement factor higher than 6 h. All told, the experimental results can provide valuable insights into the real impact of innovative technology on energy efficiency and indoor thermal comfort.

The influence of lighting and thermal environments on sleep and cognitive function in older adults

Recent research has demonstrated the significant influence of lighting and thermal conditions on cognitive performance and sleep quality. However, a notable gap exists in understanding how these factors impact older adults within their living environments. This study examined the relationship between daily lighting and thermal exposures with cognitive performance and sleep quality in older adults. Eighteen older adults, with a mean age of 75 (SD = 7.7, female = 13), participated in a three-day study. Throughout the protocol, their indoor lighting and thermal conditions were monitored using environmental sensors. Participants were instructed to complete a series of cognitive tasks twice a day. Additionally, they wore a smartwatch-type actigraph and a wearable light tracker to monitor their sleep/wake patterns and daily light exposure. The findings showed that appropriate nighttime lighting correlated with improved evening cognitive performance. Higher nighttime indoor lighting intensity positively correlated with cognitive measures, while nighttime correlated color temperature (CCT) exposure had negative correlations. Daytime melanopic equivalent daylight illuminance (MEDI) exposure significantly predicted total sleep time, with increased circadian-effective light exposure reducing sleep fragmentation. Conversely, higher nighttime lighting intensity was linked to decreased sleep efficiency. Higher bedroom temperatures were associated with improved sleep efficiency and reduced fragmentation. These findings highlight the importance of optimizing lighting conditions and maintaining comfortable temperatures in residential environments to promote cognitive performance and sleep quality among older adults.

Towards Climate, Bioclimatism, and Building Performance—A Characterization of the Brazilian Territory from 2008 to 2022

Representative weather data are fundamental to characterizing a place and determining ideal design approaches. This is particularly important for large countries like Brazil, whose extension and geographical position contribute to defining diverse climatic conditions along the territory. In this context, this study intends to characterize the Brazilian territory based on a 15-year weather record (2008–2022), providing a climatic assessment based on a climatic and bioclimatic profile for the whole country. The climate analysis was focused on temperature, humidity, precipitation, and solar radiation, followed by a bioclimatic analysis guided by the Givoni chart and the natural ventilation potential assessment. In both situations, the results were analyzed using three resolutions: country-level, administrative division, and bioclimatic zones. This study also identified representative locations for the Brazilian bioclimatic zones for a building-centered analysis based on the thermal and energy performance of a single-family house with different envelope configurations. The results proved that most Brazilian territories increased above 0.4 °C in the dry bulb temperature and reduced relative humidity. The precipitation had the highest reduction, reaching more than 50% for some locations. The warmer and drier conditions impacted also the Köppen–Geiger classification, with an increase in the number of Semi-Arid and Arid locations. The bioclimatic study showed that ventilation is the primary strategy for the Brazilian territory, as confirmed by the natural ventilation potential results, followed by passive heating strategies during the year’s coldest months. Finally, building performance simulation underlined that, in colder climates, indoor thermal comfort conditions and air-conditioning demands are less affected by solar absorptance for constructions with low U-values, while in warmer climates, low solar absorptance with intermediary U-values is recommended.

Measuring effects of insulation renewal on heating energy and indoor thermal environment in urban residence of hot-summer/cold-winter region, China

Optimizing thermal insulation in residential buildings is crucial for energy efficiency, especially in Hot Summer and Cold Winter (HSCW) region. Current research often neglects retrofitting and real-life measurements, relying instead on simulations. This study conducted insulation retrofitting on a Chengdu high-rise residential unit, focusing on the flexible heating habits locally. The insulation renewal work involved transforming the thermal insulation structure by adding insulation to all internal surfaces of the rooms' opaque structure, including external walls, internal walls, ceilings, and floors. Experiments based on residents' routines quantified energy savings and improved indoor thermal conditions under intermittent heating. Results showed a significant decrease in daily heating energy consumption by 45.10 % on average, with a maximum of 55.53 %. The retrofitted room's energy-saving rate stabilized between 50 % and 55 % after the second hour. Indoor temperatures in the retrofitted bedroom increased by 0.7 °C on average and up to 1.4 °C. Raising the heating set temperature by 2 °C resulted in a 1.1 °C increase in the retrofitted room, higher than in the non-retrofitted one. These findings provide practical insights for renovating existing residences to achieve energy efficiency in the HSCW region.

Thermal Comfort Challenges in Home-Based Enterprises: A Field Study from Surakarta’s Urban Low-Cost Housing in a Tropical Climate

The growing global concern over heat-related health risks, exacerbated by climate change, disproportionately affects low-income populations, particularly in tropical regions like Indonesia. This study investigates indoor thermal conditions in home-based enterprises (HBEs) within the informal urban settlements of Surakarta City, Indonesia, focusing on the struggle for thermal comfort under constrained conditions. By addressing the thermal comfort challenges in low-income urban housing, this research contributes to sustainable development goals, aiming to enhance living conditions in tropical climates. Our methodology included detailed field measurements of thermal comfort using standard indices in these dwellings, complemented by surveys and interviews to understand building designs, occupant behaviors, and adaptation strategies. Findings indicate that temperatures inside the dwellings frequently exceeded 30 °C during 50–60% of working hours, prompting residents to adopt coping strategies such as opening windows, adjusting work schedules, and utilizing shading devices. Space limitations necessitated multifunctional use of dwellings, exacerbating heat and humidity from activities like cooking and ironing. Despite reliance on natural ventilation, ineffective architectural layouts impeded airflow. This study highlights the urgent need for sustainable architectural solutions that accommodate the dual residential and commercial functions of these spaces, aiming to improve living conditions in such challenging environments.

Integrated demand response method for heating multiple rooms based on fuzzy logic considering dynamic price

We consider an educational building heated by a combination of district heating (DH) and a local air source heat pump. We have developed an integrated demand response method for multiple rooms, consisting of an optimization layer and a control layer, to maintain thermal comfort and save energy and costs. For the optimization layer, we apply fuzzy logic to adjust indoor temperature setpoints to respond to dynamic heat prices and propose an optimal heat supply method to find optimal heat supply schemes. For the control layer, a multi-objective model predictive control (MPC) has been developed to manage indoor thermal conditions across multiple rooms. To test and verify the integrated demand response method, we build a multi-room simulation model using the CARNOT Toolbox. The results show that adopting different indoor temperature setpoints during working and nonworking hours, combined with the MPC method, has an energy-saving potential of 9.1 % compared to maintaining a constant indoor temperature using DH alone. Adjusting temperature setpoints using fuzzy logic utilizes the building's heat storage capacity to increase energy flexibility, reaching 16.0 % savings in energy and reducing 12.6 % heating costs.

Integrating vertical greenery for complex building patterns towards sustainable urban environment

Rapid urbanization has increased the urban density and functional diversity, exacerbating environmental challenges such as urban heat islands (UHI), increased building energy consumption and carbon emissions, etc., hindering the sustainable urban development. Addressing these challenges requires innovative solutions that could offer the strategic cooling of urban buildings. Vertical greenery, affixed to building façades, offers a promising approach to provide benefits of cooling, energy savings, carbon reduction and urban space saving. However, there is a lack of quantitative design for integrating vertical greenery into complex urban buildings. Therefore, this study conducts a systematic investigation for low-rise, mid-rise, and high-rise buildings incorporating vertical greenery, while performing comprehensive assessments on indoor and outdoor thermal conditions, building energy usage, and carbon emissions. The findings suggest that low-rise buildings benefit from a vertical greenery layout, while mid-rise and high-rise buildings are better suited for a horizontal greenery layout. Compared to scenarios without greenery, buildings with vertical greenery experience a maximum reduction of 0.66 °C in outdoor air temperature and 0.72 °C in indoor air temperature, along with a 5.9 % decrease in energy consumption and carbon emissions. This study addresses urban challenges through a quantified vertical greenery design, offering valuable insights for sustainable urban development.