Reduce Building Energy Consumption Research Articles

A novel biogenic porous core/shell-based shape-stabilized phase change material for building energy saving

The application of phase change materials (PCMs) for thermal storage in construction can effectively reduce building energy consumption. However, high costs and vulnerability to leaks have hindered their application. The present study proposes two approaches for the synthesis of porous supporting matrices derived from rice husk, resulting in the formation of rice husk silica (RHS) and rice husk carbon (RHC). Then, n-octadecane and the porous materials were combined by vacuum impregnation, while the leakage resistance performance of the composite PCMs was enhanced by applying epoxy resin coating to create a shell-core structure. The results show that the n-octadecane/RHS and n-octadecane/RHC composite PCMs exhibit high latent heat potential of 106.5 J/g and 116.3 J/g, respectively. Both porous supporting structures provided the PCMs with robust structural stability and exceptional thermal conductivity. The thermal conductivity of the n-octadecane/RHS composite PCMs and n-octadecane/RHC composite PCMs reached 0.52 W/(m K) and 0.41 W/(m K), respectively. The thermal properties of the biogenic porous core/shell-based shape-stabilized PCMs were characterized by an analog T-history method, and the results demonstrated that the composite PCMs exhibited excellent and rapid heat storage and exothermic capabilities. After undergoing 300 complete heating and cooling cycles, the composite PCMs demonstrate exceptional thermal reliability and possess a high enthalpy capacity. Finally, the impact of the pore structure of RHS and RHC on the crystallization behavior of n-octadecane was discussed. Both composite PCMs can be regarded as environmentally friendly construction materials with promising thermal and acoustic properties.

Experimental and numerical study on the shear performance of stainless steel-GFRP connectors for use in precast concrete sandwich panels

Precast Concrete Sandwich Panel (PCSP) is composed of concrete load-bearing panels, thermal insulation panels, and decorative panels, which are assembled through connectors, integrating load-bearing, thermal insulation, and decorative functions. The connector bears the main shear force between the wall panels, and the shear resistance and insulation performance of the connector largely determine the mechanical stability and insulation effect of the wall panels, which is a key component in PCSPs. The current common practice is to cross assemble stainless steel insulation (SSI) connectors and Glass-Fiber-Reinforced Plastic (GFRP) connectors into PCSPs, which can reduce building energy consumption and save resources while meeting strength and insulation requirements. A large-scale pull-out test on a PCSP with intersecting SSI-GFRP connectors was conducted in this paper. The damage process and damage pattern of PCSP were observed and the shear performance of SSI-GFRP connectors was analyzed. Secondly, a numerical analysis model of the test PCSP was built using ABAQUS finite element software and its validity was verified through the test data. In addition, parameters such as connector diameter, connector number ratio and concrete strength were analyzed for their effect on the shear performance of SSI-GFRP connectors and it was found that connector diameter and connector number ratio had a significant effect. Finally, it is found that there are some differences between the classical theory for calculating the shear performance of SSI-GFRP connectors and the actual results. A theoretical correction factor (ζ) is given to improve the accuracy of the calculation of the classical theory, and its influencing factors and changing rules are investigated.

Dimensionless resolutions for heat flux decrement factor and time lag of the wall during cyclic variations in outdoor air temperature

The heat flux decrement factor (DF) and time lag (TL) are two vital indicators for assessing wall dynamic thermal performance. However, computing these indicators involves complex variables such as material thermal properties, wall thickness, and others. Therefore, exploring the inherent relation between these two indicators and the influencing parameters is an urgent problem for reducing building energy consumption. To this end, an analytical method based on the auxiliary function was employed to calculate the heat flux DF and TL of a single-layer wall. Then, the impact of the influencing factors on heat flux DF and TL were evaluated. The results showed that heat flux DF and TL are only determined by two dimensionless parameters: diffusion length and thermal efficiency coefficient. The heat flux DF decreases by at least 5 times as the diffusion length varies from 0 to 2. Besides, it is also affected by the diffusion length when the thermal efficiency coefficient (ε) is less than 5, and the smaller the ε, the smaller the heat flux DF. On the other hand, the heat flux TL increases linearly with the diffusion length initially but declines precipitously as the diffusion length approaches 6–7. When the diffusion length is the same, the heat flux TL slightly decreases as the thermal efficiency coefficient increases.

In situ carbothermal reduction of oxygen vacancies in monoclinic WO3-x film for dual-band electrochromic windows

Dual-band electrochromic windows have emerged as a promising approach to reduce building energy consumption. However, developing facile and effective method for preparing single-component dual-band electrochromic material remains a challenge. Herein, an in situ carbothermal reduction strategy was utilized to fabricate monoclinic oxygen-deficient tungsten oxide (WO3-x) for high-performance dual-band electrochromism. Polyvinylpyrrolidone (PVP–K90) underwent transformation into amorphous carbon at high temperature, serving as the reducing agent embedded in the tungsten oxide film, and in situ inducing the formation of oxygen vacancies during annealing treatment. Lastly, the amorphous carbon was gasified without weakening the transmittance of WO3-x film. The content of oxygen vacancies in WO3-x could be modulated by controlling the added amount of PVP-K90. The intrinsic generation of oxygen vacancies not only obtained a strong local surface plasmon resonance (LSPR) absorption in near-infrared (NIR) range, but also improved lithium ion (Li+) diffusion in WO3-x film. The WO3-x electrochromic film exhibited excellent dual-band electrochromic performance in optical modulation, switching time, coloring efficiency, bistability, and cycle stability. Furthermore, the WO3-x film was applied to electrochromic window to verify its available regulation in solar illumination and heat, indicating that the designed modification strategy has potential for developing a single-component dual-band electrochromic window with outstanding performance.

Research on compressive strength and thermal conductivity of lightweight phosphogypsum-based composite cementitious materials

Investigation of the mechanical and thermal properties of lightweight phosphogypsum-based cementitious materials can enhance the utilization rate of phosphogypsum-based composites and reduce building energy consumption. In this study, various amounts of hollow glass microspheres (HGMs) are incorporated into phosphogypsum-based composite cementitious materials to investigate their effects on mechanical and thermal insulation properties. Subsequently, comparisons are made between lightweight phosphogypsum-based composite cementitious materials produced by foaming and those with added HGMs. The research findings indicate that HGMs significantly mitigate the loss of compressive strength and notably reduce thermal conductivity, aligning with the development needs of lightweight and high-strength construction materials. Specifically, at a 20 % HGM dosage, the specimen exhibits a thermal conductivity of 0.2512 W·m−1·K−1, marking a 46.0 % decrease compared to specimens without HGMs. Additionally, the compressive strength measures at 25.45 MPa, reflecting a 36.4 % decline relative to specimens without HGMs. However, because of the uncontrolled pore structure and size in lightweight phosphogypsum-based composite cementitious materials produced by direct foaming, the decrease in compressive strength of foamed materials is greater than that of materials with added HGMs when the reduction in the coefficient of thermal conductivity is the same. Moreover, the compressive strength of phosphogypsum-based composite cementitious materials made with HGMs decreases more than that made with the addition of HGMs. This can be attributed to the uniform particle size of HGMs, contributing to a singular and complete pore structure within the phosphogypsum-based cementitious materials, thereby optimizing their performance.

Integrated gypsum composite material for energy storage and thermal insulation: Assessment of mechanical performance, thermal properties and environmental impact

The development of gypsum-based construction materials with energy storage and thermal insulation functions is crucial for regulating indoor temperatures, reducing building energy consumption, and mitigating CO2 emissions. In this study, graphene and expanded vermiculite (EV) were used as paraffin carriers to prepare a novel dual-carrier composite energy storage material called P/G-EV, which was developed through ultrasound, a constant-temperature water bath, and vacuum adsorption. In addition, a novel energy storage–thermal insulation integrated–gypsum (ESTIIG) composite material was developed using P/G-EV as the energy storage layer (ESL) and EV as the thermal insulation layer (TIL) compounded with phosphorus building gypsum. The thermal properties, mechanics, apparent density, temperature control performance in a real environment and environmental impact of ESTIIG were evaluated, and the temperature control mechanism was analyzed. The results reveal superior thermal stability and thermal conductivity of the P/G-EV carrier.P/G-EV overcomes the low thermal conductivity and leakage problems associated with paraffin, exhibiting a phase change temperature and latent heat of 21.7 °C and 101 J/g, respectively, during the heat absorption stage. In ESTIIG, P/G-EV and EV are compounded with phosphorus building gypsum to form an ESL and a TIL. The overall mechanical performance of ESTIIG meets the requirements of construction applications. Among the variants of ESTIIG, ESTIIG-1, with an ESL/TIL thickness ratio of 3:1, exhibits the best real-world temperature control performance and environmental benefits, providing a more stable and comfortable indoor temperature. Furthermore, this study provides data and theoretical references for the design of ESTIIG through real-world temperature control monitoring and analysis of the temperature control mechanism.

Analysis of the necessity of revising the building energy efficiency certificate for non-residential buildings in South Korea

The Building Energy Efficiency Certification (BEEC) program is a crucial government policy aimed at reducing building energy consumption and greenhouse gas emissions in numerous countries, including South Korea. This study aims to evaluate the achievable BEEC level by designing a typical building with a construction permit and analyze the appropriateness of the awarded BEEC level. We collected 327 samples of non-residential buildings from South Korea's architectural administration system and established reference building models from these samples. The buildings were categorized into four use types (office, educational, retail, or cultural) and large or small sizes. We evaluated the energy consumption of the reference buildings and assigned them a BEEC level. Retail buildings exhibited the highest energy consumption, followed by office, cultural, and educational buildings. All reference buildings had an energy consumption of less than 260 kWh/m2/yr and were awarded a BEEC level of 1 to 1++, indicating energy efficient buildings. Non-residential buildings, reflecting common design trends, achieved a BEEC level of at least level 1 without additional efforts to enhance energy efficiency. We recommend the South Korean government should revise the current BEEC rating criteria and review the certification evaluation methodology. The results of this study strongly advocate for continuous improvement of the BEEC certification system. This study is expected to enhance the effectiveness of energy efficiency policies for buildings and advance related policies.

Experimental study on solar wall by considering parametric sensitivity analysis to enhance heat transfer and energy grade using compound parabolic concentrator and pulsating heat pipe

Enhancing high-grade and rapid thermal storage for solar energy utilization is of paramount importance in reducing building energy consumption. Therefore, this study combines the Compound Parabolic Concentrator (CPC) and Pulsating Heat Pipe (PHP) to propose an integrated CPC-PHP solar wall (CPC-PHP-SW) that can enhance solar energy grade and rapid thermal storage. The mixed working fluid for CPC-PHP-SW is developed to reduce the dependence on solar radiation intensity and facilitate PHP startup. Furthermore, the operating characteristics and heat transfer performances of the CPC-PHP-SW are studied experimentally under various factors, including solar radiation intensity, working fluid, and cooling temperature. Sensitivity analyses of these three factors on heat transfer performances are conducted using Multi-factor analysis of variance. Results highlight that solar radiation intensity is the most influential factor on heat transfer performance, followed by cooling temperature, and working fluid. Moreover, employing a CPC with a concentration ratio of 2 reduces thermal resistance by up to 56.46 %, while the maximum effective thermal conductivity increases by up to 129.65 %. A recommended methanol to water ratio is 1:3, which effectively copes with a wide range of solar radiation intensity. These findings provide valuable references for the design and application of CPC-PHP-SW in building envelopes.

Research on the Design Strategy of Double–Skin Facade in Cold and Frigid Regions—Using Xinjiang Public Buildings as an Example

In the context of global warming, the focus on applying and researching double–skin facade (DSF) systems to reduce energy consumption in buildings has significantly increased. However, researchers have not thoroughly examined the performance and applicability of DSFs in severe cold regions with high winter heating demands. This study aims to evaluate the potential application of DSFs in the harsh cold cities of Northwest China and investigate their role in enhancing energy efficiency in large public buildings. Through energy consumption simulation and a comprehensive evaluation using the TOPSIS entropy weight method, the effects of applying 20 DSF schemes in four cold cities in Xinjiang (Kashgar, Urumqi, Altay, and Turpan) were analyzed. The experimental results indicate that the average EUI energy–saving rates in Kashgar, Urumqi, Altay, and Turpan are 64.75%, 63.19%, 56.70%, and 49.41%, respectively. South–facing orientation is deemed optimal for DSF in Xinjiang cities, with the highest energy–saving rate reaching 15.19%. In Kashgar, the energy–saving benefits of west–facing DSF surpass those of north–facing DSF. Conversely, the order of orientation benefits for other cities is south, north, west, and east. An analysis of heating, cooling, and lighting energy consumption reveals that Box Windows exhibit superior heating energy efficiency, while Corridors are more effective for cooling. This characteristic is also evident in the optimal installation orientation of various types of curtain walls. Given the relatively higher demand for heating compared to cooling in urban areas, Box Windows yields significant benefits when facing south, west, or north; conversely, if there is a high demand for urban cooling, Corridors should be considered in these three directions. Multistorey DSF systems are suitable for east–facing buildings in Xinjiang cities. Selecting suitable DSF schemes based on specific conditions and requirements can reduce building energy consumption. The research findings offer theoretical guidance for designing and implementing DSF in diverse cities in cold regions.

OcAPO: Fine-grained occupancy-aware, empirically-driven PDC control in open-plan, shared workspaces

Passive Displacement Cooling (PDC) is a relatively recent technology gaining attention as a means of significantly reducing building energy consumption overheads, especially in tropical climates. PDC eliminates the use of mechanical fans, instead using chilled-water heat exchangers to perform convective cooling. In this paper, we identify and characterize the impact of several key parameters affecting occupant comfort in a 1000m2 open-floor area (consisting of multiple zones) of a ZEB (Zero Energy Building) deployed with PDC units and tackle the problem of setting the temperature setpoint of the PDC units to assure occupant thermal comfort and yet conserve energy. We tackle two key practical challenges: (a) the zone-level (i.e., occupant-experienced) temperature differs significantly, depending on occupancy levels, from that measured by the ceiling-mounted thermal sensors that drive the PDC control loop, (b) sparsely deployed sensors are unable to capture the often-significant differences in ambient temperature across neighboring zones. Using extensive real-world coarser-grained measurement data (collected over 60 days under varying occupancy conditions), (a) we first uncover the various parameters that affect the occupant-level ambient temperature, and then (b) devise a trace-based model that helps identify the optimum combination of PDC setpoints, collectively across multiple zones, while accommodating variations in the occupancy levels and weather conditions. Using this trace-based model, our OcAPO system can assure ambient temperature experienced by occupants within a tolerance of 0.3°C. In contrast, the existing approach of occupancy-agnostic, rule-based setpoint control violates this tolerance interval more than 80% of the time. However, this initial model requires unnecessary and continual database lookups and is unable to derive finer-grained setpoints, thereby potentially missing opportunities for additional energy savings. We thus collected data for another 15 days, with finer-grained setpoint control in increments of 0.2∘ under varying occupancy conditions in the second phase. To determine PDC setpoints efficiently, we subsequently used the empirical data to train a KNN-based regression model. Additional studies on our real-world testbed demonstrate the regressor-based OcAPO approach is able to assure occupant-level ambient temperature within a narrow 0.2°C tolerance. We also demonstrate that the regression version of OcAPO can reduce the opening percentage of PDC valves (an indirect proxy for energy consumption) by 58.9% under low occupancy compared to the trace-based model.

Carbon reduction potential of housing retrofits: Evidence from China

Carbon emissions have become a major contributor to global climate change, with the building sector representing one-third of the global energy demand, and the residential sector accounting for 70 % of final energy demand worldwide. The energy consumption for building cooling has grown rapidly in recent years. Housing retrofits have shown potential in improving building energy efficiency and thus aligning with objectives for energy-saving and carbon emissions reduction in the residential sector. Based on survey data from 28 provinces in China, this study estimates the impacts of housing retrofits on the building energy consumption for air conditioners, as well as impacts on the resulting carbon emissions. Employing Endogenous switching regression to mitigate self-selection bias and the consequent endogeneity problem, the analysis reveals that housing retrofits can reduce building energy consumption and consequent carbon emissions. Furthermore, factors including household characteristics, building attributes and geographic location can influence both residential energy consumption and carbon emissions. In addition, low-income households, families with children and those living in self-owned houses can benefit the most from housing retrofits. This study also offers recommendations to reducing household energy consumption and carbon emissions through improved renovation practices. These insights are instrumental for policymakers in identifying targeted policy objectives across diverse demographic groups. The findings hold relevance for other developing countries with large amounts of inefficient housing stock during rapid urbanization, and those prone to global warming, aiding their pursuit of Sustainable Development Goals.

Thermal performance of a wooden pipe-embedded building envelope using a low-grade heat source in extreme cold climate conditions

A pipe-embedded wall can effectively reduce building energy consumption in winter. Most of the research on this concept to date has used traditional building materials such as concrete and brick. This paper reports on a wooden pipe-embedded wall allowing more flexible pipe locations, which can be used to reduce heat load in winter. An experimental assessment was developed to investigate the building assemblies thermal performance and the results were used to develop an understanding of its thermal energy saving potential, and as an input for the validation of a numerical model of same. A 3D computational fluid dynamics model of the pipe-embedded wall was developed and applied to assess the thermal performance of the wall under boundary conditions beyond the capabilities of the experimental assessment. Further, the influence of five parameters including the outdoor temperature and pipe positions were studied. A method was proposed for selecting the pipe layer's optimal location. The results show dual thermal impacts of the pipe layer: active heating and passive insulation. Using 8 °C water reduces internal surface heat transfer by 42.5 % under −20 °C outdoor temperature conditions. This is akin to an 18 °C outdoor temperature rise. Furthermore, another interesting result is that increasing the wall material thermal resistance can sometimes increase energy consumption. This study provides a reference for designing and optimizing net zero energy buildings in extreme cold climate conditions.

Enhancing Building Energy Efficiency: Leaf Transpiration Inspired Construction of Lignin-Based Wood Plastic Composites for Building Energy Conservation

Incorporating phase change materials (PCMs) into buildings represents a strategic method for reducing reliance on air conditioning systems and decreasing energy usage consequently. Inspired by leaf veins providing channels for transpiration, lignin porous carbon (LPC) was synthesized by chemical activation, showing a vein pore structure. The capillary network system of the LPC provided more channel to adsorb PCM through surface tension and capillary force, achieving an impressive loading capacity of LPC for polyethylene glycol (PEG) (75%), which demonstrated exceptional heat storage capability (133.21 J/g). The lignin-derived wood-plastic composite (L-WPC) was further prepared. With the gradual increase of LPC/PEG, the latent heat of L-WPC increased gradually. The ΔHm, ΔHc and energy storage efficiency of L-WPC-50 (incorporated 50 wt% LPC/PEG-75) reached 39.99 J/g, 42.65 J/g and 90.26%, respectively. The vein pore structure of LPC also provided a thermal conductivity link for L-WPC. L-WPC-50 demonstrated an increased thermal conductivity (0.66 W/(m·K)) and a reduced thermal diffusion coefficient (0.24 mm2/s), optimizing the effectiveness of the phase transition. Additionally, L-WPC-50 displayed satisfactory mechanical properties and dimensional stability, with tensile strength, bending modulus and water absorption thickness swelling rate measuring 14.40 MPa, 1043.72 MPa, and 1.61% respectively. It introduced a feasible approach for utilizing biomass in enhancing building energy efficiency, marking a significant stride towards reducing building energy consumption and advocating sustainable energy practices.

Building a sustainable future: Exploring the nexus between climate awareness and thermal insulation choices in new home construction

Climate change is considered a major threat to the environment and society as a whole. Reducing building energy consumption through the use of thermal insulation is one way of combating climate change. This study examines the impact of climate change awareness on the pre-construction decision of Lebanese homeowners to use thermal insulation in their new homes. A model building consisting of a typical 160 m2 single-family home was used and its thermal loads were calculated in two cases: insulated and uninsulated case, in three different locations in Lebanon: Beirut, Chtaura, and Bcharre-Arz. The thermal loads were calculated using two methods: the degree-days empirical method, and the Hourly Analysis Program software numerical method. The computations showed energy reduction ranging between 23% in the coastal region to 52% in high mountains when thermal insulation of thickness 5 cm was used. The investment payback period ranged from 4.3 years in the coastal region to 1.5 years in the high mountains. A survey addressed to 100 respondents was used to understand how Lebanese homeowners’ decision to use thermal insulation was affected by knowledge of the obtained results. The survey results showed that climate change awareness has a high impact on this decision; however, the cost seems to play an important role in the owners’ final decision on whether or not to use thermal insulation. Spreading awareness about climate change and the payback periods of building thermal insulation will increase its use since the number of respondents refusing to use thermal insulation drastically decreased after being informed about its payback period.

Optimizing the dimensional ratio and orientation of residential buildings in the humid temperate climate to reduce energy consumption (Case: Rasht Iran)

Today, the increase in the number of cities and greenhouse gas increases has led to the intensification of global warming. The construction industry has had a significant impact on this crisis. Therefore, using passive solutions such as optimizing building proportions and proper orientation in any climate can significantly help reduce building energy consumption and greenhouse gases. The research aims to optimize the proportions of residential buildings and their orientation to minimize the building's energy consumption in the city of Rasht with a moderate climate. For this purpose, a three-story building with dimensions of 1:1 was selected, and the energy consumption of the building, including the load of cooling, heating, and lighting, was calculated in the north-south and east-west dimensions up to the ratio of 1–10. This research has used validated software to calculate energy consumption. Then, the most optimal mode was selected in terms of proportionality; the energy consumption of the building with a different orientation compared to the geographical north was calculated for each degree up to 360°. The results showed that the energy consumption of the building with a ratio of 1:4 with east-west elongation was 155.29 kWh/m2, which has the lowest energy consumption compared to other modes and is also compatible with the construction and building industry. Also, the building with zero-degree orientation to the geographic north and east-west elongation has the lowest carbon dioxide production and annual energy consumption, which are 2107 kg/m2 and 146.28 kWh/m2, respectively. By using two primary parameters, i.e., building orientation and aspect ratio, this research presents a valid innovation in optimizing the energy consumption of buildings. This research is focused on the detailed analysis of the environmental performance of a building in Rasht climate and determining the best form and orientation to reduce energy consumption and environmental efficiency.

Characteristics and Application Analysis of a Novel Full Fresh Air System Using Only Geothermal Energy for Space Cooling and Dehumidification

To effectively reduce building energy consumption, a novel full fresh air system with a heat source tower (HST) and a borehole heat exchanger (BHE) was proposed for space cooling and dehumidification in this paper. The cooling system only adopts geothermal energy to produce dry and cold fresh air for space cooling and dehumidification through the BHE and HST, which has the advantage of non-condensate water compared to BHE systems integrated with a fan coil or chilled beam. Based on the established mathematical model of the cooling system, this paper analyzed the system characteristics, feasibility, operation strategy, energy performance, and cost-effectiveness of the proposed model in detail. The results show that the mathematical model has less than 10% error in estimating the system performance compared to the practical HST–BHE experimental set up. Under the specific boundary conditions, the cooling and dehumidification capacity of this system increases with the decrease in the air temperature, air moisture content, and inlet water temperature of the HST. The optimal cooling capacity and the system COP can be achieved when the air–water flow ratio is at 4:3. A case study was conducted in a residential building in Shenyang with an area of about 1800 m2. It was found that this system can fully meet the cooling and dehumidification demand in such a residential building. The operation strategy of the cooling system can be optimized by adjusting the air–water flow ratio from 4:3 to 3:2 during the early cooling season (7 June–1 July) and end cooling season (3 August–1 September). As a result, the average COP of the cooling system during the whole cooling season can be improved from 6.1 to 8.7. Compared with the air source heat pump (ASHP) and the ground source heat pump (GSHP) for space cooling, the proposed cooling system can achieve an energy saving rate of 123% and 26%, respectively. Considering that the BHE of the GSHP can be part of the proposed HST–BHE cooling system, the integration of the HST and GHSP for space cooling (and heating) is strongly recommended in actual applications.

Application of Renewable Energy in Green Buildings and Energy Consumption Optimization

INTRODUCTION: With the increasing global awareness of sustainable development and environmental protection, green building has become one of the important development directions in the construction industry. The application of sustainable type energy in the construction industry is of great significance in reducing building energy consumption and environmental pollution. This study aims to explore the application of sustainable types of energy and conduct research on energy consumption optimization. OBJECTIVE: The aim of this study is to analyze the current situation of the application of sustainable types of energy in the construction industry, to explore its impact on the energy consumption of buildings, and to propose corresponding optimization strategies in order to achieve the goal of sustainable development of green buildings in China. METHODS: This study adopts a combination of literature review and case study; firstly, a literature review on the application of sustainable types of energy, sorting out its technical characteristics and application effects; then, several typical cases are selected to analyze its energy application and energy consumption in buildings; finally, relevant strategies and suggestions for optimizing the energy consumption are put forward by combining the results of the literature review and the case study. RESULTS: Through the literature review and case analysis, it is found that sustainable types of energy, such as solar energy and wind energy, have been widely used in buildings and achieved certain energy-saving effects. However, there are also some problems, such as inefficient energy utilization and high cost. To address these problems, this study proposes a series of optimization strategies, including suggestions for optimizing energy system design, improving energy utilization efficiency, and reducing energy costs. CONCLUSION: This study concludes that the application of sustainable types of energy in green buildings is an important way to optimize building energy consumption and sustainable development. Through measures such as optimizing energy system design and improving energy utilization efficiency, building energy consumption can be further reduced, environmental pollution can be reduced, and the development of the construction industry can be promoted. However, further research and practice are still needed to continuously improve relevant technologies and policies to promote the application and development of sustainable types of energy in buildings.

Planning and design of an architectural energy supply system based on photovoltaic-thermal technology

China’s building energy consumption is growing and the energy consumption of the whole process of buildings accounts for more than 46.5% of the country’s total energy consumption, of which the proportion of energy consumption used for heating, ventilation and air conditioning is as high as 50%. Solar energy has the greatest potential to achieve energy conservation in buildings. Buildings are the best carrier for solar energy utilization because of the advantages of local collection and local application. The combination of solar energy and buildings can meet a variety of energy and health needs in buildings, among which solar photovoltaic and CSP building integration technology is an important way to reduce building energy consumption and improve indoor air quality. This article presents a PV/T-based thermal storage wall system that efficiently utilizes solar energy. It outlines the PV/T technology’s fundamental principles and provides a detailed description of the system’s construction and operation, highlighting critical components like the solid thermal storage medium and heat transfer via a heat pump. The analysis indicates improved energy utilization and favorable economic feasibility. This technology offers a practical solution for the construction industry, promoting sustainable energy practices and environmental conservation.

A novel heating strategy and its optimization of solar–air source heat pump heating system for rural buildings in northwest China

In the rural areas of Northwest China, the utilization of clean and renewable energy is deemed a crucial measure for reducing building energy consumption and environmental pollutant emissions. This paper focuses on constructing a simulation platform for a solar-assisted air source heat pump heating system. A rural residential building in Yongshou County, Shaanxi Province, serves as an illustrative example. A novel flexible temperature control method with a feedback controller in sub-area and period is proposed in this paper, alongside the selection of three distinct objective functions aimed at optimizing the heating system. The simulation results indicate an average temperature of 17.0 °C throughout the heating cycle, with a peak temperature of 18.7 °C. Moreover, the solar fraction is measured at 25.11%, underscoring the significance of collector area and heat storage tank volume as primary factors in system design. The results also demonstrate that across various optimization objectives, the life cycle cost optimization scheme yields greater economic benefits, while the target building unit heating cost optimization scheme boasts the shortest static payback period and lowest unit heating cost. Conversely, the solar fraction optimization scheme stands out for its superior environmental benefits. These findings offer valuable insights for the design of heating systems tailored to diverse objectives.

Controlling the Size of Hydrotalcite Particles and Its Impact on the Thermal Insulation Capabilities of Coatings.

This study focuses on the development of high-performance insulation materials to address the critical issue of reducing building energy consumption. Magnesium-aluminum layered double hydroxides (LDHs), known for their distinctive layered structure featuring positively charged brucite-like layers and an interlayer space, have been identified as promising candidates for insulation applications. Building upon previous research, which demonstrated the enhanced thermal insulation properties of methyl trimethoxysilane (MTS) functionalized LDHs synthesized through a one-step in situ hydrothermal method, this work delves into the systematic exploration of particle size regulation and its consequential effects on the thermal insulation performance of coatings. Our findings indicate a direct correlation between the dosage of MTS and the particle size of LDHs, with an optimal dosage of 4 wt% MTS yielding LDHs that exhibit a tightly interconnected hydrotalcite lamellar structure. This specific modification resulted in the most significant improvement in thermal insulation, achieving a temperature difference of approximately 25.5 °C. Furthermore, to gain a deeper understanding of the thermal insulation mechanism of MTS-modified LDHs, we conducted a thorough characterization of their UV-visible diffuse reflectance and thermal conductivity. This research contributes to the advancement of LDH-based materials for use in thermal insulation applications, offering a sustainable solution to energy conservation in the built environment.