The investment risk management of the existing building energy-saving renovation project for ESCO cannot be separated from the scientific risk measurement and evaluation. The investment risk assessment is the basis of...The investment risk management of the existing building energy-saving renovation project for ESCO cannot be separated from the scientific risk measurement and evaluation. The investment risk assessment is the basis of investment decision and project implementation. Based on the content analysis and balance of evaluation principle of investment risk evaluation on the existing building energy-saving renovation project, we set up three levels of existing building energy-saving renovation project investment risk evaluation index system, use fuzzy comprehensive evaluation method to evaluate the quantitative process, get the scientific assessment of the investment risk of existing building energy-saving renovation project, and support the investment risk response strategy and control measures of existing building energy-saving renovation project for ESCO.展开更多
An energy consumption analysis based on the heating characteristic of a building with central heat exchanger in a university of Tianjin was done,and the feasibility of intermittent heating with variable speed pumps wa...An energy consumption analysis based on the heating characteristic of a building with central heat exchanger in a university of Tianjin was done,and the feasibility of intermittent heating with variable speed pumps was discussed. By comparing various methods of energy consumption analysis,a modified Bin method based on the weather data in Tianjin was adopted. The heat consumption of the buildings under intermittent heating mode was calculated and compared with continuous heating mode,the result shows that intermittent heating can reduce energy consumption for 1 941 759 kW·h,save standard coal for 341 t,and reduce pump power consumption for 72 679 kW·h annually. Intermittent operation by means of varying the pump frequency not only leads to savings in fuel consumption and reduction in pollutant emissions,but also reduces operating costs significantly and it is an ideal energy-saving method. By analyzing the results,the recommendations of heating operation regulation and the transformation of pipe network were proposed separately to different kinds of buildings in colleges,such as laboratory building,teaching building.展开更多
Energy-saving design of residential building is an important part of energy-saving architectural design. Planning and design of residential buildings in Hanzhong area should pay more attention to the building orientat...Energy-saving design of residential building is an important part of energy-saving architectural design. Planning and design of residential buildings in Hanzhong area should pay more attention to the building orientation, sunshine, summer ventilation and wind resistance in winter and so on, so as to create favorable conditions for energy-saving design of single buildings. The geographical location, climatic characteristics, residents living habits and indoor and outdoor thermal environment situation were analyzed in this paper, and combined with the existing problems of energy conservation in the planning and layout of residential buildings in Hanzhong area. Based on the investigation, this paper drew some conclusions to provide references for the energy-saving planning and design of urban residential buildings in the local area.展开更多
The development of existing building energy saving reconstruction market depends on the interaction among service market, capital market and technology market. Analysis of the characteristics of both building energy-s...The development of existing building energy saving reconstruction market depends on the interaction among service market, capital market and technology market. Analysis of the characteristics of both building energy-saving service market, capital market and technology market, and analysis on the role of existing building energy saving reconstruction market development in energy conservation and emission reduction development strategy, energy-saving transformation policy implementation and promotion of other industries landing, will be conducive to energy-saving renovation of existing buildings market cultivation and development.展开更多
Government regulation on building energy saving starts earlier in America, Holland, Japan and other developed countries, and has accumulated wealthy experience which is worth reference for China. According to practica...Government regulation on building energy saving starts earlier in America, Holland, Japan and other developed countries, and has accumulated wealthy experience which is worth reference for China. According to practical work of building energy efficiency in China, the government regulation should to be divided into two stages: recent advance and forward continued promotion of industry. In short term, we should cultivate and improve energy efficiency market as the main task by means of enhancing awareness of energy conservation, accelerating heating system reform, implementing effective encouraging policy and setting up building energy efficiency sign system and etc. While in long term, we should put emphasis on upgrading and development of building energy efficiency industry by ways of improving standard and norm system, constructing technological guarantee system and forming socialized cooperation system and etc.展开更多
The construction of relevant standards for building carbon emission assessment in China has just started,and the quantitative analysis method and evaluation system are still imperfect,which hinders the development of ...The construction of relevant standards for building carbon emission assessment in China has just started,and the quantitative analysis method and evaluation system are still imperfect,which hinders the development of low-carbon building design.Therefore,the use of intelligent energy management system is very necessary.The purpose of this paper is to explore the design optimization of low-carbon buildings based on intelligent energy management systems.Based on the proposed quantitative method of building carbon emission,this paper establishes the quota theoretical system of building carbon emission analysis,and develops the quota based carbon emission calculation software.Smart energy management system is a low-carbon energy-saving system based on the reference of large-scale building energy-saving system and combined with energy consumption.It provides a fast and effective calculation tool for the quantitative evaluation of carbon emission of construction projects,so as to realize the carbon emission control and optimization in the early stage of architectural design and construction.On this basis,the evaluation,analysis and calculation method of building structure based on carbon reduction target is proposed,combined with the carbon emission quota management standard proposed in this paper.Taking small high-rise residential buildings as an example,this paper compares and analyzes different building structural systems from the perspectives of structural performance,economy and carbon emission level.It provides a reference for the design and evaluation of low-carbon building structures.The smart energy management system collects user energy use parameters.It uses time period and time sequence to obtain a large amount of data for analysis and integration,which provides users with intuitive energy consumption data.Compared with the traditional architectural design method,the industrialized construction method can save 589.22 megajoules(MJ)per square meter.Based on 29270 megajoules(MJ)per ton of standard coal,the construction area of the case is about 8000 m2,and the energy saving of residential buildings is 161.04 tons of standard coal.This research is of great significance in reducing the carbon emission intensity of buildings.展开更多
With the current,our country social economy rapid development,people's living standard and quality of life and therefore have got improved,at the same time,it is the concept of environmental protection and energy ...With the current,our country social economy rapid development,people's living standard and quality of life and therefore have got improved,at the same time,it is the concept of environmental protection and energy saving is also enhanced value,many fields in our country environmental protection and energysaving concept can be seen in the application,especially the application in building water supply and drainage design more widely,to protect the environment,to maximize the use of limited resources,how to reasonable use of water resources in building water supply and drainage construction,above is current the paper mainly discusses the problems in the construction field,this paper based on environmental protection and energy-saving concept,discusses its application in the building water supply and drainage design,for your reference.展开更多
This paper presents a stable, nonlinear, adaptive control scheme for building heating and cooling systems. The proposed controller utilizes the principle of adaptive one step ahead control and aims at reducing the ene...This paper presents a stable, nonlinear, adaptive control scheme for building heating and cooling systems. The proposed controller utilizes the principle of adaptive one step ahead control and aims at reducing the energy consumed for heating or cooling a building. The design steps are discussed in details and a proof of global stability is also provided. Also, the performance of the proposed controller is demonstrated on a simulated building thermal model.展开更多
The energy-saving reconstruction market of existing buildings is a complex system.It includes three subsystems:service market,capital market and technology market.The service market takes the relationship between ener...The energy-saving reconstruction market of existing buildings is a complex system.It includes three subsystems:service market,capital market and technology market.The service market takes the relationship between energy service companies and owners as the core to establish service associated relationships.The capital market is based on the mechanism of"investment guarantees and risk sharing"to form structures of the capital market.The technology market relies on the"industry-university-research"mode to build technology supporting platforms.Being interdependent and mutually restricted,the three subsystems form the complete system of existing buildings in energy-saving reconstruction.展开更多
Existing large-scale public building energy saving renovation is the inherent requirement of sustainable development, it has been proved that implementing the energy performance contracting mode in the Existing large ...Existing large-scale public building energy saving renovation is the inherent requirement of sustainable development, it has been proved that implementing the energy performance contracting mode in the Existing large public buildings energy-saving is an effective way both at home and abroad. EPC mode has obvious characteristics for the ESCO and the customers, it can meet the basic requirements of large public buildings energy-saving, such as the width of funding sources, program specifi cation, advanced technology, information fl ow and management level higher, etc. Under the condition of market economy, it also provides a broad platform for the ESCO implements building energy saving transformation, which is conducive to the realization of the win-win cooperation between the parties, and to promote the healthy development of the existing large public building energy saving reconstruction.展开更多
Information asymmetry phenomenon and the differences between the main body's earning targets,which are existing in the building energy saving field,have made the game behaviors of its economic activities become in...Information asymmetry phenomenon and the differences between the main body's earning targets,which are existing in the building energy saving field,have made the game behaviors of its economic activities become inevitable.There are strategies choice between government departments and the developers,when the building energy saving work is carried out under the government control.Based on the players based assumptions,the path of player's behavior strategy choices is analyzed,expected revenue models are established and mixed Nash equilibrium is obtained in this paper.Based on the analysis results,the incentive strategy enlightenment could be concluded that it is particularly important to design the scientific incentive system for developers to develop energy-saving buildings reasonably and for the government to implement effective control;the role of informal system in encouraging developers to develop energy-saving buildings should not be ignored.展开更多
Building fresh air supply needs to meet certain regulations and fit people’s ever-growing indoor air quality de-mand.However,fresh air handling requires huge energy consumption that goes against the goal of net-zero ...Building fresh air supply needs to meet certain regulations and fit people’s ever-growing indoor air quality de-mand.However,fresh air handling requires huge energy consumption that goes against the goal of net-zero energy buildings.Thus,in this work,an adaptive fresh air pre-handling system is designed to reduce the cool-ing and heating loads of HVAC system.The sky-facing surface of the system uses electrochromic mechanism to manipulate the optical properties and thus make full use of solar energy(solar heating)and deep space cold source(radiative cooling)by switching between heating and cooling modes.In the cooling mode,the sky-facing surface shows a transmittance of down to zero,while the reflectance is high at 0.89 on average.In the heating mode,the electrochromic glass is highly transparent,allowing the sunlight to reach the solar heat absorber.To obtain the energy-saving potential under different climates,six cities were selected from various climate regions in China.Results show that the adaptive fresh air pre-handling system can be effective in up to 55.4%time of a year.The maximum energy-saving ratios for medium office,warehouse,and single-family house can reach up to 11.52%,26.62%,and 18.29%,respectively.In addition,the system shows multi-climate adaptability and broad application scenarios,making it a potential solution to building energy saving.展开更多
This work focused on characterizing and improving the thermal behavior of metal sheet roofing.To decrease the heat transfer from the roof into a building,we investigated the efficiency of four types of phase change ma...This work focused on characterizing and improving the thermal behavior of metal sheet roofing.To decrease the heat transfer from the roof into a building,we investigated the efficiency of four types of phase change materials,with different melting points:PCMІ,PCM II,PCM III and PCM IV,when used in conjunction with a sheet metal roof.The exterior metal roofing surface temperature was held constant at 50℃,60℃,70℃and 80℃,using a thermal source(halogen lights)for 360 min to investigate and compare the thermal performance of the metal sheet roofing with and without phase change materials for each condition.The thermal behaviors of the phase change materials were analyzed by differential scanning calorimeter(DSC).The results showed the melting points of PCMІ,PCM II,PCM III and PCM IV were around 45℃,50℃,55℃and 59℃,respectively.The integration of PCM IV into the metal roofing sheet increased the thermal performance by reducing the room temperature up to 2.8%,1.4%,1.0%and 0.7%when compared with the normal metal roof sheet,at the controlled temperatures of 50℃,60℃,70℃and 80℃,respectively.The thermal absorption of the phase change materials also caused a time delay in the model room reaching a steady temperature.The integration of phase change materials with metal roofing sheets resulted in better thermal performance and conservation of electrical energy by reducing the demand for cooling.展开更多
The related existing energy saving index system of buildings is deficient in direction, index coverage, depth, and technological and economic considerations. Aiming at the deficient existing research and with the adva...The related existing energy saving index system of buildings is deficient in direction, index coverage, depth, and technological and economic considerations. Aiming at the deficient existing research and with the advancement of energy saving of buildings in China from northern heating regions to southern hot summer and cold winter regions, selecting residential buildings in hot summer and cold winter regions as the research object, and through much evaluation index reference and repeated demonstrations and the borrowing of literature research home and abroad and relevant energy saving standards, filters and eliminates energy efficient technologies evaluation indexes according to the design principle of index system, the factors influencing the energy saving of residential buildings are evaluated, index system weight is established by adopting analytic hierarchy process, and finally the evaluation index system of energy saving technologies of residential buildings in hot summer and cold winter area of China is established. Each target layer includes five standard layer indexes and sixteen index layer indexes. The standard layer of evaluation index, namely primary indexes, includes the technological, energy saving effect, economic, environmental, and social indexes. The secondary indexes are selected based on the principles of concision, comprehensiveness, representativeness and operability.展开更多
Buildings contribute to 33%of total global energy consumption,which corresponds to 38%of greenhouse gas emissions.Enhancing building’s energy efficiency remains predominant in mitigating global warming.Advance-ments ...Buildings contribute to 33%of total global energy consumption,which corresponds to 38%of greenhouse gas emissions.Enhancing building’s energy efficiency remains predominant in mitigating global warming.Advance-ments in thermal energy storage(TES)techniques using phase change material(PCM)have gained much attention among researchers,primarily to minimize energy consumption and to promote the use of renewable energy sources.PCM technology stays as the most promising technology for developing high-performance and energy-efficient buildings.The major drawback of PCM is its poor thermal conductivity which limits its potential use which could be resolved by dispersing conductive nanofillers.The acquired database on synthesis routes,properties,and performance of nano-dispersed phase change materials(NDPCMs)with various techniques presented in the paper should deliver useful information in the production of NDPCMs with desirable characteristics mainly for building construction applications.An outline of contemporary developments and use of NDPCMs as TES medium is delivered.Finally,a brief discussion on challenges and the outlook was also made.In-depth research is needed to explore the fundamental mechanisms behind the enhanced thermal conductivity of NDPCM with nanofillers dispersion and also a thorough investigation on how these mechanisms drive improvement in building performance.展开更多
Comfort in buildings is one of the most requested value to reach. Today, designers have to deal with so many technical features including outer appearance, air-conditioning, structural layouts, acoustic insulation and...Comfort in buildings is one of the most requested value to reach. Today, designers have to deal with so many technical features including outer appearance, air-conditioning, structural layouts, acoustic insulation and inner treatments, materials bio-compatibility, material recycling and reuse, water wasting and so on. In the same time, costumers want to buy buildings which won’t cost a lot in terms of heating and cooling as in the past. Besides, every single apartment, loft, office etc., even if there are many of them in a single building, has to be very quiet. Voluntary or compulsory standards, protocols and state laws lead the designers throughout the project and in some cases to the final in field tests too. Nevertheless, different sort of calculations, leading philosophy, expected results, parameters and tags are included in order to achieve the final aims. In this paper, energy efficiency and acoustic performances of buildings are discussed, proposing and comparing designing solutions for a specific case study.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 71573188)the Soft Science Research Project of Ministry of Housing and Urban - Rural Development (Grant No. 2013-R1-14)Tianjin Social Sciences Planning Post-funded Projects (Grant No. TJGLHQ1403)
文摘The investment risk management of the existing building energy-saving renovation project for ESCO cannot be separated from the scientific risk measurement and evaluation. The investment risk assessment is the basis of investment decision and project implementation. Based on the content analysis and balance of evaluation principle of investment risk evaluation on the existing building energy-saving renovation project, we set up three levels of existing building energy-saving renovation project investment risk evaluation index system, use fuzzy comprehensive evaluation method to evaluate the quantitative process, get the scientific assessment of the investment risk of existing building energy-saving renovation project, and support the investment risk response strategy and control measures of existing building energy-saving renovation project for ESCO.
文摘An energy consumption analysis based on the heating characteristic of a building with central heat exchanger in a university of Tianjin was done,and the feasibility of intermittent heating with variable speed pumps was discussed. By comparing various methods of energy consumption analysis,a modified Bin method based on the weather data in Tianjin was adopted. The heat consumption of the buildings under intermittent heating mode was calculated and compared with continuous heating mode,the result shows that intermittent heating can reduce energy consumption for 1 941 759 kW·h,save standard coal for 341 t,and reduce pump power consumption for 72 679 kW·h annually. Intermittent operation by means of varying the pump frequency not only leads to savings in fuel consumption and reduction in pollutant emissions,but also reduces operating costs significantly and it is an ideal energy-saving method. By analyzing the results,the recommendations of heating operation regulation and the transformation of pipe network were proposed separately to different kinds of buildings in colleges,such as laboratory building,teaching building.
文摘Energy-saving design of residential building is an important part of energy-saving architectural design. Planning and design of residential buildings in Hanzhong area should pay more attention to the building orientation, sunshine, summer ventilation and wind resistance in winter and so on, so as to create favorable conditions for energy-saving design of single buildings. The geographical location, climatic characteristics, residents living habits and indoor and outdoor thermal environment situation were analyzed in this paper, and combined with the existing problems of energy conservation in the planning and layout of residential buildings in Hanzhong area. Based on the investigation, this paper drew some conclusions to provide references for the energy-saving planning and design of urban residential buildings in the local area.
基金supported by the National Natural Science Foundation of China (Grant No. 71573188)the Soft Science Research Project of Ministry of Housing and Urban - Rural Development (Grant No. 2013-R1-14)Tianjin Social Sciences Planning Post-funded Projects (Grant No. TJGLHQ1403)
文摘The development of existing building energy saving reconstruction market depends on the interaction among service market, capital market and technology market. Analysis of the characteristics of both building energy-saving service market, capital market and technology market, and analysis on the role of existing building energy saving reconstruction market development in energy conservation and emission reduction development strategy, energy-saving transformation policy implementation and promotion of other industries landing, will be conducive to energy-saving renovation of existing buildings market cultivation and development.
基金supported by National Natural Science Foundation (Grant No. 71171141)Post-funded Projects of Social Science Planning in Tianjin (Grant No. TJGLHQ1403)
文摘Government regulation on building energy saving starts earlier in America, Holland, Japan and other developed countries, and has accumulated wealthy experience which is worth reference for China. According to practical work of building energy efficiency in China, the government regulation should to be divided into two stages: recent advance and forward continued promotion of industry. In short term, we should cultivate and improve energy efficiency market as the main task by means of enhancing awareness of energy conservation, accelerating heating system reform, implementing effective encouraging policy and setting up building energy efficiency sign system and etc. While in long term, we should put emphasis on upgrading and development of building energy efficiency industry by ways of improving standard and norm system, constructing technological guarantee system and forming socialized cooperation system and etc.
基金supported by“Key Technology Research on Operational Performance Improvement of the Green Building”(2020YFS0060)Key Project of Science and Technology Department of Sichuan Province+2 种基金supported by“Creative VR Teaching and Learning Research Based on‘PBL+’and Multidimensional Collaboration”(JG2021-721)“Reform in the Mode and Practice of Architecture Education with the Characteristics of Geology”(JG2021-672)Education Quality and Teaching Reform Project of Higher Education in Sichuan Province in 2021–2023.
文摘The construction of relevant standards for building carbon emission assessment in China has just started,and the quantitative analysis method and evaluation system are still imperfect,which hinders the development of low-carbon building design.Therefore,the use of intelligent energy management system is very necessary.The purpose of this paper is to explore the design optimization of low-carbon buildings based on intelligent energy management systems.Based on the proposed quantitative method of building carbon emission,this paper establishes the quota theoretical system of building carbon emission analysis,and develops the quota based carbon emission calculation software.Smart energy management system is a low-carbon energy-saving system based on the reference of large-scale building energy-saving system and combined with energy consumption.It provides a fast and effective calculation tool for the quantitative evaluation of carbon emission of construction projects,so as to realize the carbon emission control and optimization in the early stage of architectural design and construction.On this basis,the evaluation,analysis and calculation method of building structure based on carbon reduction target is proposed,combined with the carbon emission quota management standard proposed in this paper.Taking small high-rise residential buildings as an example,this paper compares and analyzes different building structural systems from the perspectives of structural performance,economy and carbon emission level.It provides a reference for the design and evaluation of low-carbon building structures.The smart energy management system collects user energy use parameters.It uses time period and time sequence to obtain a large amount of data for analysis and integration,which provides users with intuitive energy consumption data.Compared with the traditional architectural design method,the industrialized construction method can save 589.22 megajoules(MJ)per square meter.Based on 29270 megajoules(MJ)per ton of standard coal,the construction area of the case is about 8000 m2,and the energy saving of residential buildings is 161.04 tons of standard coal.This research is of great significance in reducing the carbon emission intensity of buildings.
文摘With the current,our country social economy rapid development,people's living standard and quality of life and therefore have got improved,at the same time,it is the concept of environmental protection and energy saving is also enhanced value,many fields in our country environmental protection and energysaving concept can be seen in the application,especially the application in building water supply and drainage design more widely,to protect the environment,to maximize the use of limited resources,how to reasonable use of water resources in building water supply and drainage construction,above is current the paper mainly discusses the problems in the construction field,this paper based on environmental protection and energy-saving concept,discusses its application in the building water supply and drainage design,for your reference.
文摘This paper presents a stable, nonlinear, adaptive control scheme for building heating and cooling systems. The proposed controller utilizes the principle of adaptive one step ahead control and aims at reducing the energy consumed for heating or cooling a building. The design steps are discussed in details and a proof of global stability is also provided. Also, the performance of the proposed controller is demonstrated on a simulated building thermal model.
基金supported by National Natural Science Fundation of China(Grant No.71573188)Later-stage Humanities and Social Sciences Subsidized Project of Ministry of Education(Grant No.16JHQ031)Tianjin Social Sciences Planning Post-funded Projects(Grant No.TJGLHQ1403).
文摘The energy-saving reconstruction market of existing buildings is a complex system.It includes three subsystems:service market,capital market and technology market.The service market takes the relationship between energy service companies and owners as the core to establish service associated relationships.The capital market is based on the mechanism of"investment guarantees and risk sharing"to form structures of the capital market.The technology market relies on the"industry-university-research"mode to build technology supporting platforms.Being interdependent and mutually restricted,the three subsystems form the complete system of existing buildings in energy-saving reconstruction.
基金supported by the National Natural Foundation of China (Grant No. 71171141)Project of the Ministry of Housing and Urban-Rural Development (Grant No. 2013-R1-14)the Tianjin Municipal Social Science Planning Project (Grant No. TJGLHQ1403)
文摘Existing large-scale public building energy saving renovation is the inherent requirement of sustainable development, it has been proved that implementing the energy performance contracting mode in the Existing large public buildings energy-saving is an effective way both at home and abroad. EPC mode has obvious characteristics for the ESCO and the customers, it can meet the basic requirements of large public buildings energy-saving, such as the width of funding sources, program specifi cation, advanced technology, information fl ow and management level higher, etc. Under the condition of market economy, it also provides a broad platform for the ESCO implements building energy saving transformation, which is conducive to the realization of the win-win cooperation between the parties, and to promote the healthy development of the existing large public building energy saving reconstruction.
基金supported by the National Natural Science Foundation of China(Grant No.71171141)
文摘Information asymmetry phenomenon and the differences between the main body's earning targets,which are existing in the building energy saving field,have made the game behaviors of its economic activities become inevitable.There are strategies choice between government departments and the developers,when the building energy saving work is carried out under the government control.Based on the players based assumptions,the path of player's behavior strategy choices is analyzed,expected revenue models are established and mixed Nash equilibrium is obtained in this paper.Based on the analysis results,the incentive strategy enlightenment could be concluded that it is particularly important to design the scientific incentive system for developers to develop energy-saving buildings reasonably and for the government to implement effective control;the role of informal system in encouraging developers to develop energy-saving buildings should not be ignored.
基金the support from National Natural Sci-ence Foundation of China(52276178)Natural Science Foundation of Jiangsu Province,China(BK20200373).
文摘Building fresh air supply needs to meet certain regulations and fit people’s ever-growing indoor air quality de-mand.However,fresh air handling requires huge energy consumption that goes against the goal of net-zero energy buildings.Thus,in this work,an adaptive fresh air pre-handling system is designed to reduce the cool-ing and heating loads of HVAC system.The sky-facing surface of the system uses electrochromic mechanism to manipulate the optical properties and thus make full use of solar energy(solar heating)and deep space cold source(radiative cooling)by switching between heating and cooling modes.In the cooling mode,the sky-facing surface shows a transmittance of down to zero,while the reflectance is high at 0.89 on average.In the heating mode,the electrochromic glass is highly transparent,allowing the sunlight to reach the solar heat absorber.To obtain the energy-saving potential under different climates,six cities were selected from various climate regions in China.Results show that the adaptive fresh air pre-handling system can be effective in up to 55.4%time of a year.The maximum energy-saving ratios for medium office,warehouse,and single-family house can reach up to 11.52%,26.62%,and 18.29%,respectively.In addition,the system shows multi-climate adaptability and broad application scenarios,making it a potential solution to building energy saving.
基金The authors would like to thank the Thailand Science Research and Innovation(TSRI),Faculty of Science,Naresuan University for providing financial support to this research work,and our research center.
文摘This work focused on characterizing and improving the thermal behavior of metal sheet roofing.To decrease the heat transfer from the roof into a building,we investigated the efficiency of four types of phase change materials,with different melting points:PCMІ,PCM II,PCM III and PCM IV,when used in conjunction with a sheet metal roof.The exterior metal roofing surface temperature was held constant at 50℃,60℃,70℃and 80℃,using a thermal source(halogen lights)for 360 min to investigate and compare the thermal performance of the metal sheet roofing with and without phase change materials for each condition.The thermal behaviors of the phase change materials were analyzed by differential scanning calorimeter(DSC).The results showed the melting points of PCMІ,PCM II,PCM III and PCM IV were around 45℃,50℃,55℃and 59℃,respectively.The integration of PCM IV into the metal roofing sheet increased the thermal performance by reducing the room temperature up to 2.8%,1.4%,1.0%and 0.7%when compared with the normal metal roof sheet,at the controlled temperatures of 50℃,60℃,70℃and 80℃,respectively.The thermal absorption of the phase change materials also caused a time delay in the model room reaching a steady temperature.The integration of phase change materials with metal roofing sheets resulted in better thermal performance and conservation of electrical energy by reducing the demand for cooling.
文摘The related existing energy saving index system of buildings is deficient in direction, index coverage, depth, and technological and economic considerations. Aiming at the deficient existing research and with the advancement of energy saving of buildings in China from northern heating regions to southern hot summer and cold winter regions, selecting residential buildings in hot summer and cold winter regions as the research object, and through much evaluation index reference and repeated demonstrations and the borrowing of literature research home and abroad and relevant energy saving standards, filters and eliminates energy efficient technologies evaluation indexes according to the design principle of index system, the factors influencing the energy saving of residential buildings are evaluated, index system weight is established by adopting analytic hierarchy process, and finally the evaluation index system of energy saving technologies of residential buildings in hot summer and cold winter area of China is established. Each target layer includes five standard layer indexes and sixteen index layer indexes. The standard layer of evaluation index, namely primary indexes, includes the technological, energy saving effect, economic, environmental, and social indexes. The secondary indexes are selected based on the principles of concision, comprehensiveness, representativeness and operability.
基金The authors would like to acknowledge Universiti Malaysia Pahang (UMP) forthe financial assistance given under RDU 213308 and DRS, Sunway University through SunwayUniversity’s International Research Network Grant Scheme (IRNGS) 2021 (STR-IRNGS-SETRCNMET-01-2021) for carrying out this work.
文摘Buildings contribute to 33%of total global energy consumption,which corresponds to 38%of greenhouse gas emissions.Enhancing building’s energy efficiency remains predominant in mitigating global warming.Advance-ments in thermal energy storage(TES)techniques using phase change material(PCM)have gained much attention among researchers,primarily to minimize energy consumption and to promote the use of renewable energy sources.PCM technology stays as the most promising technology for developing high-performance and energy-efficient buildings.The major drawback of PCM is its poor thermal conductivity which limits its potential use which could be resolved by dispersing conductive nanofillers.The acquired database on synthesis routes,properties,and performance of nano-dispersed phase change materials(NDPCMs)with various techniques presented in the paper should deliver useful information in the production of NDPCMs with desirable characteristics mainly for building construction applications.An outline of contemporary developments and use of NDPCMs as TES medium is delivered.Finally,a brief discussion on challenges and the outlook was also made.In-depth research is needed to explore the fundamental mechanisms behind the enhanced thermal conductivity of NDPCM with nanofillers dispersion and also a thorough investigation on how these mechanisms drive improvement in building performance.
文摘Comfort in buildings is one of the most requested value to reach. Today, designers have to deal with so many technical features including outer appearance, air-conditioning, structural layouts, acoustic insulation and inner treatments, materials bio-compatibility, material recycling and reuse, water wasting and so on. In the same time, costumers want to buy buildings which won’t cost a lot in terms of heating and cooling as in the past. Besides, every single apartment, loft, office etc., even if there are many of them in a single building, has to be very quiet. Voluntary or compulsory standards, protocols and state laws lead the designers throughout the project and in some cases to the final in field tests too. Nevertheless, different sort of calculations, leading philosophy, expected results, parameters and tags are included in order to achieve the final aims. In this paper, energy efficiency and acoustic performances of buildings are discussed, proposing and comparing designing solutions for a specific case study.