Research on Energy Performance in Buildings

A special issue of Buildings (ISSN 2075-5309). This special issue belongs to the section "Building Energy, Physics, Environment, and Systems".

Deadline for manuscript submissions: closed (20 April 2024) | Viewed by 13965

Special Issue Editors


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Guest Editor
China Academy of Building Research, Beijing 100013, China
Interests: building energy saving; indoor built environment; renewable energy utilization; carbon emission reduction in building sector
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
School of Architecture and Transportation Engineering, Guilin University Of Electronic Technology, Guilin 541004, China
Interests: building simulation; radiant cooling system; building energy conservation
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Energy consumption and carbon emissions in the building sector have become the focus of global attention under the goal of curbing global warming. However, many factors, such as building materials, envelope, electromechanical system, etc., have an impact on energy consumption, and the carbon emissions, involving all stages throughout the life cycle of buildings and thus making it complex to reduce the energy utilization and environmental impacts. Through the innovation of energy conservation and carbon emission reduction technology, improving building energy efficiency and low carbon performance has become a crucial research theme.

The main aim of this Special Issue is to explore advanced theories, technologies, and tools in the field of building energy efficiency and securing low carbon emissions under the background of carbon neutrality. Potential topics include, but are not limited to:

(1)Building energy conservation;

(2)Evaluation of building energy efficiency and low carbon performance;

(3)Low-carbon technology of green buildings throughout the life cycle;

(4)Renewable energy utilization;

(5)Bridge the low-carbon development of buildings and urban renewal;

(6)Low-carbon technology of historical buildings;

(7)Technology for zero-carbon building and the application.

Dr. Xiaoping Li
Dr. Rong Hu
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Buildings is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • energy consumption
  • carbon emission
  • energy conservation
  • green building
  • low carbon
  • carbon neutrality
  • renewable energy

Published Papers (12 papers)

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Research

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26 pages, 46539 KiB  
Article
Thermal Environment Analysis and Optimization for Large Space Buildings with Radiant Cooling Floors: A Case Study of Xianyang International Airport
by Rong Hu, Haolin Wang, Junqi Liang, Xiaoping Li, Wenheng Zheng and Gang Liu
Buildings 2024, 14(5), 1355; https://doi.org/10.3390/buildings14051355 - 9 May 2024
Viewed by 431
Abstract
Radiant cooling floors combined with ventilation systems have been widely applied in large space buildings. However, there has been a lack of research on system control strategies for their adaptation to weather changes. This study aimed to find control strategies for radiant cooling [...] Read more.
Radiant cooling floors combined with ventilation systems have been widely applied in large space buildings. However, there has been a lack of research on system control strategies for their adaptation to weather changes. This study aimed to find control strategies for radiant cooling floors combined with displacement ventilation systems used in large space buildings in order to achieve energy conservation and environmental improvement. Supply air temperature and cooling surface temperature were determined to be the control variables. It was found that cooling capacity of the combined system and the comfort index, PMV (predicted mean vote), were linear in relation to the supply air temperature and cooling surface temperature. The linear equations regarding cooling capacity and PMV were established separately using environment data, and then the optimal region was determined. A case study on Terminal 3 of Xi’an Xianyang International Airport was conducted. The thermal environment was investigated through on-site measurements, questionnaires, and numerical simulations with CFD (computational fluid dynamics). It was found that supply air temperature and cooling surface temperature had a significant impact on PMV, and less impact on the cooling capacity. Therefore, it was determined that the supply air temperature should be altered first when the indoor temperature exceeds the upper limit, and then the cooling surface temperature should be changed if the indoor environment continues to overheat with the supply air temperature set to 18 °C. Thus, the supply air temperature was kept at 18 °C, and the floor surface temperature was set to be 22 °C on a high-temperature day. The average PMV was 0.87, and the cooling capacity of the combined system was 200 W/(m2·K), according to the CFD simulation. In addition, the surface heat transfer coefficient of the cooling floor was found to be 10.26 W/(m2·K). This research provides important references for the design and operational management of radiant cooling floors in large space buildings. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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20 pages, 7206 KiB  
Article
Research on Relative Humidity and Energy Savings for Air-Conditioned Spaces without Humidity Control When Adopting Air-to-Air Total Heat Exchangers in Winter
by Ming Dong, Jialiang Zhang, Liufeng Zhang, Lianbo Liu and Xingqiang Zhang
Buildings 2024, 14(4), 969; https://doi.org/10.3390/buildings14040969 - 1 Apr 2024
Viewed by 513
Abstract
In view of the problem that the exchange effectiveness is calculated according to a fixed value or only considering the influence of outdoor air parameters when analyzing the suitability of total heat recovery for plate heat recovery equipment in air-conditioned spaces without humidity [...] Read more.
In view of the problem that the exchange effectiveness is calculated according to a fixed value or only considering the influence of outdoor air parameters when analyzing the suitability of total heat recovery for plate heat recovery equipment in air-conditioned spaces without humidity control, the indoor humidity calculation model and moisture balance equation were established in this research to predict relative indoor humidity. Moreover, the relationship between total heat recovery, effective heat recovery, and the reduction in outdoor air heating load was analyzed using a psychrometric chart of the outdoor air treatment process. Referring to the standard for weather data of building energy efficiency in the Ningbo region, 6 typical days were taken as the calculation conditions. The moisture balance differential equation was solved using MATLAB software to obtain numerical solutions for the hourly indoor air humidity ratio, relative humidity, exchange effectiveness, and effective heat recovery when adopting an air-to-air total heat exchanger in an air-conditioned room of an office, classroom, or commercial building in the winter. The results indicate that, under the calculation conditions, the relative indoor humidity of commercial buildings is relatively high, making it unsuitable for a total heat exchanger. The relative humidity of indoor air in offices and classrooms can be maintained above 30%, and the total exchange effectiveness of a total heat exchanger is between 45% and 100%. The effective total heat recovery was calculated as sensible heat recovery under most calculation conditions. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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15 pages, 3544 KiB  
Article
An Experimental Study on Heat Recovery Performances of Three-Dimensional Heat Pipes in Air-Conditioning Systems
by Yanqiang Di, Haiyan Di, Chen Zhao, Zichen Lu, Xiaona Li and Juan Leng
Buildings 2024, 14(2), 355; https://doi.org/10.3390/buildings14020355 - 27 Jan 2024
Cited by 1 | Viewed by 948
Abstract
The applications of conventional heat pipes have been hindered by a few weaknesses, such as the low heat recovery effectiveness, the cross-pollution of fresh and exhaust air, and the difficult switch modes between winter and summer working conditions. In order to find solutions [...] Read more.
The applications of conventional heat pipes have been hindered by a few weaknesses, such as the low heat recovery effectiveness, the cross-pollution of fresh and exhaust air, and the difficult switch modes between winter and summer working conditions. In order to find solutions for those problems, a three-dimensional heat pipe exchanger was developed, and an experimental platform was built to test the heat recovery effectiveness of this heat pipe exchanger under different working conditions. Moreover, the operating performances of the three-dimensional heat pipe exchanger unit were monitored throughout one year in a hospital located in the hot summer and cold winter region of China. The field measurement results indicated that the heat recovery effectiveness could be effectively improved by reducing the air volume and the up-wind speed, increasing the cold air and hot air inlet temperature, and increasing the rows of pipes. According to optimizing the structure and operation parameters, the heat recovery efficiencies of the three-dimensional heat pipe exchanger increased by 65~85%. The recommended operation parameters of the three-dimensional heat pipe exchanger in winter and summer for indoor exhaust air temperature were 20 ± 2 °C and 22 ± 2 °C, respectively. The heat recovery effectiveness could reach up to 66% and 64.5% when the indoor and outdoor air temperature differences were higher than 11 °C and 5 °C in winter and summer, respectively. This study provides effective, reliable, and easily implementable methods for the application of three-dimensional heat pipe heat recovery devices in building HVAC systems. It offers guidance for the future design of heat pipe heat recovery devices. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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10 pages, 10121 KiB  
Article
Analysis of the Energy Consumption of Old Public Buildings in South Korea after Green Remodeling
by Hansol Lee and Gyeong-Seok Choi
Buildings 2023, 13(12), 3081; https://doi.org/10.3390/buildings13123081 - 11 Dec 2023
Viewed by 805
Abstract
In Korea, green remodeling of public buildings will be mandatory from 2025, and about 30,000 old public buildings nationwide will conduct green remodeling every year. Therefore, in this study, green remodeling was promoted to improve energy efficiency for existing public buildings located in [...] Read more.
In Korea, green remodeling of public buildings will be mandatory from 2025, and about 30,000 old public buildings nationwide will conduct green remodeling every year. Therefore, in this study, green remodeling was promoted to improve energy efficiency for existing public buildings located in Siheung, Gyeonggi-do. A remodeling method was developed to reduce the cooling and heating load of the building and reduce construction costs. The development technology was applied to the demonstration building to improve the insulation and airtightness performance of the building. In order to analyze the effect of improving the energy performance of the building, the simulation results and energy consumption before and after remodeling were analyzed. The demand for heating energy decreased by about 68.95%, and the demand for cooling energy decreased by 35.21%. According to an analysis of actual energy consumption, the average monthly energy consumption savings from January to September was 17.4%. It was confirmed that the savings were the highest at 35.4% in February, during winter. Applying the remodeling method developed in this study is expected to contribute to reducing greenhouse gas emissions by reducing energy efficiency and energy consumption of existing buildings. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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16 pages, 9566 KiB  
Article
Field Study on Impact of Mechanical Pressurization on Pressure Distribution in High-Rise Buildings
by Kyung-Hwan Ji, Su-Ji Choi and Jae-Hun Jo
Buildings 2023, 13(12), 3039; https://doi.org/10.3390/buildings13123039 - 6 Dec 2023
Cited by 1 | Viewed by 1016
Abstract
In high-rise buildings, the excessive pressure differences cause various problems, and architectural and mechanical measures are always applied. In this study, pressure measurements on a 67-story high-rise building were conducted to evaluate the effect of mechanical pressurization on the pressure distribution. Absolute pressure [...] Read more.
In high-rise buildings, the excessive pressure differences cause various problems, and architectural and mechanical measures are always applied. In this study, pressure measurements on a 67-story high-rise building were conducted to evaluate the effect of mechanical pressurization on the pressure distribution. Absolute pressure measurement devices were installed at 28 points on 10 floors, a full-scale pressure profile of the test building was derived, and the pressure distributions on the main floors were reviewed. Four pressurization modes for the test building were considered, and the variation in the pressure distribution for each mode was analyzed. The results showed that mechanical pressurization reduced the pressure difference on the lobby floor by approximately 18%. Although it did not exert an apparent impact on the pressure difference due to the stack effect, pressurizing the entire floor serves as the most effective way of reducing the excessive pressure difference. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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19 pages, 5881 KiB  
Article
Developing a Practical Thermal Performance Index for Radiant Terminals—Structural Thermal Resistance
by Xiang Zhou, Dandan Wang, Yunliang Liu, Maohui Luo, Seyed Mohammad Hooshmand and Andreas Wagner
Buildings 2023, 13(12), 2938; https://doi.org/10.3390/buildings13122938 - 24 Nov 2023
Viewed by 771
Abstract
Radiant terminals have been widely applied in heating and cooling systems. However, few existing thermal performance evaluation indices can reflect the influence of structural forms on heat transfer performance. This study introduces the structural thermal resistance (Rs) to rapidly evaluate [...] Read more.
Radiant terminals have been widely applied in heating and cooling systems. However, few existing thermal performance evaluation indices can reflect the influence of structural forms on heat transfer performance. This study introduces the structural thermal resistance (Rs) to rapidly evaluate the structure form’s effects. First, theoretical analysis and experimental tests were introduced. Three types of terminals, including the copper conduit graphite plate (CCGP), plastic tube-embedded metal plate (PTMP), and capillary network-embedded structural plate (CNSP) were tested in the laboratory. Then, the CNSP terminals were taken as validation examples. The results show that the Rs values of the same type of radiant terminal tend to be stable and constant. The variations in Rs within the same type of radiant terminals were small both under cooling and heating conditions. Only when the terminal structure changed, the Rs would change. This suggests that the Rs can reflect the complex heat transfer processes inside the radiant terminals while distinguishing different terminal types. The validation analysis showed an average relative error of 3.4% and 2.9% for cooling and heating, respectively. Lastly, the potential application of Rs in practical applications was discussed, and a Python-based online tool was developed to help design, operate, and evaluate radiant terminals. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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16 pages, 4101 KiB  
Article
Optimizing Window Glass Design for Energy Efficiency in South Korean Office Buildings: A Hierarchical Analysis Using Energy Simulation
by Yu-Jeong Lee, Sang-Hee Kim, Ji-Hye Ryu and Kweon-Hyoung Lee
Buildings 2023, 13(11), 2850; https://doi.org/10.3390/buildings13112850 - 14 Nov 2023
Viewed by 947
Abstract
The world is emphasizing the need for building design that considers energy performance to deal with climate problems. South Korea has constantly been tightening the design standards for saving building energy but with a focus on thermal performance and equipment systems. Accordingly, this [...] Read more.
The world is emphasizing the need for building design that considers energy performance to deal with climate problems. South Korea has constantly been tightening the design standards for saving building energy but with a focus on thermal performance and equipment systems. Accordingly, this study conducted an energy simulation experiment on office buildings with different window-to-wall ratios (WWRs) to propose a smart glazing plan to improve energy performance. An energy simulation experiment was performed on office buildings with varying WWRs to hierarchically analyze the influence of building window performance elements, including the heat transmission coefficient (U-value), visible light transmittance (VLT), and solar heat gain coefficient (SHGC), on building energy performance. The analysis showed that SHGC had the most significant impact on the heating and cooling load, by 22.13%, with the influences of the variables being 12.4% for the U-value, 4.78% for VLT, and 82.83% for SHGC. The results showed that the solar heat gain coefficient (SHGC) had the greatest impact on energy performance among window performance elements, and the effect increased significantly in certain WWRs. Moreover, to improve the energy performance of buildings with higher WWRs, it is essential to reflect the optimum composition of the U-value and SHGC on the window plan. This study’s findings propose measures to supplement existing window plans focusing on thermal performance. Furthermore, these results hold academic value in providing concrete grounds for that. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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16 pages, 8113 KiB  
Article
Analysis of the Operational Outcomes of an Energy-Sharing System for Low-Carbon Energy Community in South Korea
by Jiyoung Eum, Hansol Lee and Gyeong-Seok Choi
Buildings 2023, 13(11), 2797; https://doi.org/10.3390/buildings13112797 - 7 Nov 2023
Viewed by 718
Abstract
The transition to a net-zero energy system is being promoted in the energy sector, which has led to the creation of energy prosumers. These produce, consume, and trade energy using renewable energy systems installed in buildings or complexes. Here, a community was set [...] Read more.
The transition to a net-zero energy system is being promoted in the energy sector, which has led to the creation of energy prosumers. These produce, consume, and trade energy using renewable energy systems installed in buildings or complexes. Here, a community was set as the target to apply the concept of an energy prosumer at the individual building and regional levels. Energy-sharing systems were divided into three categories: energy production, energy storage, and energy management. Energy-sharing systems centered on electrical energy—photovoltaic, battery energy storage, and energy management systems—were installed in two communities located in South Korea, and the energy-sharing effects of the system operation were reported. Monthly power consumption in spring and fall exhibited significant savings of approximately three times that of winter consumption, owing to the energy-sharing systems. Daily hourly power-consumption patterns differed on weekdays and weekends because of the weekday working and building-use hours of the communities. Energy could be shared between communities and buildings because of surplus energy. More surplus power was available for energy sharing on weekends because power consumption was lower. Because energy trading and sharing are restricted, the related laws are being revised. Therefore, a low-carbon community can be realized through surplus energy trading and sharing technology between communities and buildings as renewable energy systems spread owing to low carbonization. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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13 pages, 4088 KiB  
Article
Study on the Performance of a New Ultra-Low Temperature Air Source Heat Pump (ASHP) Unit in Cold Regions
by Yanqiang Di, Chen Zhao, Xueli Lian, Xiaolong Li, Daorina Bao and Jinxing Liu
Buildings 2023, 13(8), 2107; https://doi.org/10.3390/buildings13082107 - 20 Aug 2023
Viewed by 1040
Abstract
Low air temperature and frosting have been reported as the critical factors that greatly attenuate the efficiency and performance of the ASHP in cold regions. In order to ensure the potential prevalence of the ASHP in cold regions of China, a new ultra-low [...] Read more.
Low air temperature and frosting have been reported as the critical factors that greatly attenuate the efficiency and performance of the ASHP in cold regions. In order to ensure the potential prevalence of the ASHP in cold regions of China, a new ultra-low temperature ASHP unit was developed, and the field measurement was carried out in an office building where these ASHP units were installed in Shanxi Province. Results showed that a coefficient of performance (COP) of 1.83 was obtained at the ultra-low environmental temperature of −25 °C. Meanwhile, measured results indicated significant frosting suppression and improved heating performance under three typical frosting conditions. In addition, long-term measurement results revealed that the mean COP and COPsys reached up to 3.34 and 2.63, respectively, indicating a higher performance in the cold regions of China. Consequently, the corresponding CO2 emission reached 11.3 kg per year and per square meter, and the annual total cost on the unit reduced by 15.8% compared with the conventional ASHP, which meant that the total investment could be covered in the second year. The reduced CO2 emission and the annual cost implied that the ASHP unit could produce better environmental and economic benefits. Findings of this study revealed that this ultra-low temperature ASHP unit had a better performance under cold environment, which offered a possibility for the prevailing of the ASHP in cold or extremely cold regions, as well as could contribute to the carbon peaking and neutralization. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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16 pages, 3157 KiB  
Article
Development of a Heat Consumption Model Group and Analysis of Economic Adjustments and Carbon Reduction Efforts in Centralized Heating Upgrades in the Beijing Urban–Rural Fringe
by Yimin Liu, Zhe Tian, Yong Cao, Yue Cen, Qing Qiao and Xiaolin Wang
Buildings 2023, 13(7), 1821; https://doi.org/10.3390/buildings13071821 - 18 Jul 2023
Viewed by 674
Abstract
Large-scale clean-heating renovations are being carried out in northern China as part of important measures to optimize energy infrastructure, improve the atmospheric environment, and minimize peak CO2 emissions. Because rural areas in the urban–rural fringe are close to the city center, they [...] Read more.
Large-scale clean-heating renovations are being carried out in northern China as part of important measures to optimize energy infrastructure, improve the atmospheric environment, and minimize peak CO2 emissions. Because rural areas in the urban–rural fringe are close to the city center, they have several advantages in centralized heating reforms, but there are no effective means to measure whether a transformation is economical or has good environmental effects. In this paper, based on an actual reconstruction project, 100 typical households were selected for a related test. These typical households evinced convergence and possessed certain regional characteristics; therefore, the applicability of the models had certain limitations. To make sure that the relevant factors were fully considered in establishing the model, a prediction model group was established regarding heat consumption in winter (four models in total) that could predict the actual effect well. Lastly, the authors used the model group to calculate economic effects and CO2 emission reduction in rural heating transformations in Beijing under different heating methods. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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Review

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24 pages, 3284 KiB  
Review
A Review of Studies on Heat Transfer in Buildings with Radiant Cooling Systems
by Rong Hu, Shilin Sun, Jincan Liang, Zhiping Zhou and Yingde Yin
Buildings 2023, 13(8), 1994; https://doi.org/10.3390/buildings13081994 - 4 Aug 2023
Cited by 1 | Viewed by 1669
Abstract
Due to their benefits in interior thermal comfort, energy saving, and noise reduction, radiant cooling systems have received wide attention. Radiant cooling systems can be viewed as a part of buildings’ maintenance structure and a component of cooling systems, depending on their construction. [...] Read more.
Due to their benefits in interior thermal comfort, energy saving, and noise reduction, radiant cooling systems have received wide attention. Radiant cooling systems can be viewed as a part of buildings’ maintenance structure and a component of cooling systems, depending on their construction. This article reviews studies on heat exchange in rooms utilizing radiant cooling systems, including research on conduction in radiant system structures, system cooling loads, cooling capacity, heat transfer coefficients of cooling surfaces, buildings’ thermal performance, and radiant system control strategy, with the goal of maximizing the benefits of energy conservation. Few studies have examined how radiant cooling systems interact with the indoor environment; instead, earlier research has focused on the thermal performance of radiant cooling systems themselves. Although several investigations have noted variations between the operating dynamics of radiant systems and conventional air conditioning systems, the cause has not yet been identified and quantified. According to heat transfer theory, the authors suggest that additional research on the performance of radiant systems should consider the thermal properties of inactive surfaces and that buildings’ thermal inertia should be used to coordinate radiant system operation. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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20 pages, 3120 KiB  
Review
A Review on the Impacts of Urban Heat Islands on Outdoor Thermal Comfort
by Jianlin Ren, Kaizhe Shi, Zhe Li, Xiangfei Kong and Haizhu Zhou
Buildings 2023, 13(6), 1368; https://doi.org/10.3390/buildings13061368 - 23 May 2023
Cited by 11 | Viewed by 3443
Abstract
The worsening urban heat island (UHI) effect poses a great challenge to the thermal comfort of people outdoors. However, there has not been a summary of the mechanisms by which UHI affects outdoor thermal comfort (OTC). This paper reviews the commonly used OTC [...] Read more.
The worsening urban heat island (UHI) effect poses a great challenge to the thermal comfort of people outdoors. However, there has not been a summary of the mechanisms by which UHI affects outdoor thermal comfort (OTC). This paper reviews the commonly used OTC evaluation indexes, data collection methods, and mitigation measures and discusses the relationship between UHI and OTC. The review is limited to peer-reviewed journal publications found in five databases: Science Direct, Scopus, Google Scholar, PubMed, and Web of Science. The review results indicate that physiological equivalent temperature (PET), universal thermal climate index (UTCI), and wet bulb globe temperature (WBGT) are the most widely used indexes in outdoor thermal comfort studies. The data collection methods mainly include questionnaire surveys, measurement, simulation, and formula calculation. There are four main approaches to mitigating the UHI effect in order to improve the comfort of people outdoors: vegetation strategies, water strategies, urban planning strategies, and material strategies. Future research can focus on developing OTC research methods and indexes and combine thermal comfort with visual comfort, auditory comfort, etc. to better evaluate the overall comfort. Full article
(This article belongs to the Special Issue Research on Energy Performance in Buildings)
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