Solar Energy In Buildings Research Articles

Numerical and experimental investigation of a single-body PVT using a variable air volume control algorithm

Photovoltaic thermal (PVT) collectors that can achieve maximum efficiency from solar irradiation can be critical concepts for meeting energy demand in residential applications. Even though there is much research on increasing heat transfer, multifunctional designs that provide homogeneous results are limited. This study explores the production of electricity and hot air from a novel design of a PVT. A new perforated copper plate design has been proposed to achieve maximum efficiency by providing homogeneous cooling in the PVT. Firstly, numerical analysis of this design was performed using Ansys Fluent software, then tested experimentally. The highest and average electrical and thermal efficiency of PVT are obtained as 17.62 %, 15.63 %, and 76.75 %, 43.68 %. In experiments conducted under winter conditions, the maximum temperature value in the PVT was measured as 41.54 °C. Moreover, the payback period of the PVT system was calculated as 6.1 years. The proposed PVT collector can be used as a new model for integrating solar energy in buildings with almost zero energy. Considering the eco-design, this PVT design can contribute net positive carbon, ecological footprint, and green manufacturing.

Passive Solar Energy Building

Passive Solar Energy Building

Study on the dynamic thermal response of phase change material integrated wall under indoor-outdoor dual thermal disturbances

The study mainly explored the dynamic thermal response of phase change material integrated wall (PCMW) under indoor-outdoor dual thermal disturbances (IODTD). A dual wave thermal disturbance dynamic boundary condition was proposed for PCMW based on the outdoor meteorological data and typical solar energy building analytical models of Lhasa, Yinchuan and Xi'an in China. The influence of different construction modes on the thermal performance of PCMW was numerically investigated by the sensible heat capacity method under IODTD. Then determined the crucial thermophysical parameters of PCM and analyzed the variation characteristics of temperature and heat flux fields of PCMW. The heat transfer frequency responses of different walls to outdoor thermal disturbances were calculated by the harmonic response method. The results indicated that the optimal location of PCM was on the interior side of the wall, and the critical values of phase change temperature and latent heat were 16 °C and 120 kJ/kg, respectively. It presented the maximum temperature and heat flux were 10 % and 36.2 % greater than ordinary walls (OW). Compared with OW, the attenuation and delay time of PCMW on outdoor sol-air temperature wave performed significantly, which plotted a higher decrement factor and longer time lag under external disturbances of different orders.

Application of Photovoltaic and Solar Thermal Technologies in Buildings: A Mini-Review

Buildings account for a significant proportion of total energy consumption. The integration of renewable energy sources is essential to reducing energy demand and achieve sustainable building design. The use of solar energy has great potential for promoting energy efficiency and reducing the environmental impact of energy consumption in buildings. This study examines the applications of photovoltaic and solar thermal technologies in the field of architecture, demonstrating the huge potential of solar energy in building applications. To ensure a fresh and thorough review, we examine literature that encompasses the advancements made in the utilization of solar energy in buildings over the past decade. The key factors to consider in this study are reliability, performance, cost and aesthetics in real applications of photovoltaic and solar thermal technologies in the field of architecture, which have a significant impact on people’s acceptance of solar energy technology. Recent developments in feasible and effective optimization solutions for solar energy technologies are summarized. Accurate and convenient simulation techniques are also summarized for reference. The results show that the rapid progress of BIPV systems is fueled by advancements in three crucial areas: enhancing solar cell and module efficiency, reducing manufacturing costs and achieving a competitive levelized cost of electricity. The results can provide researchers with a reference for understanding recent technological developments in the integration of solar energy into buildings.

Reconstruction of narrowband solar radiation for enhanced spectral selectivity in building-integrated solar energy simulations

Solar radiation is a critical factor in advanced envelope design and solar energy's building integration, necessitating a shift from broadband solar radiation analyses towards more precise narrowband or spectrum-focused approaches. Understanding the performance potential of spectral-selective materials or structures requires accurate solar spectral information at specified locations, a feature often overlooked by conventional modeling tools. This work presents an innovative solar decomposing model capable of differentiating key solar irradiation components—visible and infrared—from broadband solar irradiance, without the need for expensive spectrum measurements. Our approach employs the extreme boosting regression tree method and leverages existing or easily derivable data from typical weather files. An exploratory analysis of the importance and interaction of different features in predicting solar irradiation components is also conducted. The results show that the proposed algorithm has an R2 of 0.981 and 0.990, RMSE of 18.280 and 18.390, and MAE of 7.989 and 8.011, for predicting VIS and NIR amount in DNI, respectively (for the strongest model using all the predictors within the dataset). This research offers an added layer of practicality by including case studies demonstrating how the solar decomposition models serve in real-world applications, especially in the integration of wavelength-selective devices like window systems and transparent solar cells into advanced envelope designs. Such real-world testing has verified the presence of a disparity between the power output calculation of NIR-selective transparent photovoltaics upon the broadband solar radiation data and the suggested narrowband solar radiation data, potentially resulting in a maximum deviation of 15.7 %. The decomposing models developed empower researchers and designers to generate new weather files comprising narrowband solar irradiance data, thereby enhancing their capacity to examine the influence of spectral-selective materials on a building's solar performance using existing solar simulation programs. The proposed method will be further improved by including more data from different climate zones and weather characteristics in the training model and validating through field measurements.

A Comparative Study on the Distribution Models of Incident Solar Energy in Buildings with Glazing Facades

The accurate distribution of solar energy on indoor walls is the basis of simulating the indoor thermal environment, and its specific distribution changes all the time due to the influence of solar azimuth and altitude angle. By analyzing the assumptions of each model, the existing solar energy distribution models are eight kinds in all and are divided into three categories. The solar radiation models in TRNSYS, EnergyPlus, and Airpak software all use the absorption-weighted area ratio method, which assumes that a single interior surface is a whole, but the detailed assumptions of the models used in the three software are different. In the Radiosity-irradiation method, the indoor surfaces are discretized into small surfaces for calculation. The calculation accuracy of solar radiation distribution indoors can be controlled by the number of discrete small surfaces. The Radiosity-irradiation method is implemented by using Matlab software programming in this paper. Through the numerical calculation and analysis of typical cases, the solar distribution results of the absorption-weighted area ratio method and the Radiosity-irradiation method all show the asymmetry. The asymmetrical ratio of direct solar radiation varies during the time between 7.96–9.89, and the minimum turns up at 11:30 in the summer solstice. The asymmetrical ratio of diffuse solar radiation is 3.23 constantly. The asymmetrical ratio of total solar energy is mainly influenced by the direct and diffuse solar feat gain and its value changes in the range from 3.4 to 4.45 in the summer solstice. Calculation comparison and error analysis on the solar radiation models used in TRNSYS, EnergyPlus, and Airpak software are conducted. There are significant errors in the simulation results of all three software. TRNSYS has the highest error among the three software as its results do not change over time. For EnergyPlus, the distribution ratio of floor 1 is too large. Airpak has the smallest error, but the solar radiation distribution ratios of the indoor surfaces near the south glazing facade are underrated, especially the indoor surfaces that have not been exposed to direct solar radiation.

Smart Operating Range Monitoring of Solar PV Cell with Integrated Phase Change Materials by Using Solar Deep Learning Model

This research aims to demonstrate that a one-of-a-kind microencapsulated bio-based PCM may be utilized in the passive collection of solar energy in buildings. The research makes use of a PCM with thermal properties within the comfort zone but is also able to track the performance of solar photovoltaic panels. This allows the research to be more accurate. Because of this, the research can produce outcomes that are more accurate. After finishing the step before this one, the next thing that needs to be done is creating novel composite concrete panels. This step follows the completion of the phase before it. The outcomes of the mechanical and thermal tests served as the basis for determining the best composition of the concrete mix that should be used for making this panel. The method concludes with the construction of a test structure using composite walls as the primary building material.

Biomass and solar energy in buildings, energetic dark greenhouse, an economic approach analysis

The use of different energy sources and the worry of running out of some of them in the modern world have made factors such as environmental pollution and even energy sustainability vital. Vital resources for humanity include water, environment, food, and energy. As a result, building strong trust in these resources is crucial because of their interconnected nature. Sustainability in security of energy, water and food, generally decreases costs and improves durability. This study introduces and describes the components of a system named “Desktop Energetic Dark Greenhouse” in the context of the quadruple nexus of water, environment, food, and energy in urban life. This solution can concurrently serve to strengthen the sustainable security of water, environment, food, and energy. For home productivity, a small-scale version of this project was completed. The costs and revenues for this system have been determined after conducting an economic study from the viewpoints of the investor and the average household. The findings indicate that the capital return period is around five years from the investor’s perspective. The capital return on investment for this system is less than 4 years from the standpoint of the households. According to the estimates, this system annually supplies about 20 kg of vegetables or herbs, which means about one third of the annual needs of a family.

Experimental Study on Heat Storage/Release Performances of Composite Phase Change Thermal Storage Heating Wallboards Based on Photovoltaic Electric-Thermal Systems

The rapid development of photovoltaic technology provides more possibilities for the efficient application of solar energy in buildings. This research proposed a phase change material (PCM) heat storage wall system with a “four-layer” structure. A performance test platform using low voltage DC was built to study the mechanism of electric thermal conversion of the graphene electrothermal film and the heat transfer characteristics of the “four-layer” structure. As shown in the experimental results, under the voltages of 24 V, 32 V and 42 V, (1) with the increase in voltage, the temperature of the electrothermal film increases, while its electrothermal conversion efficiency decreases from 85% to 75%; (2) during the heat storage process, because of its latent heat storage characteristics, the temperature of the PCM wallboard is 3~5 °C lower than that of the cement wallboard, but the effective heat storage increases by 59~65%; (3) during the heat release process, the effective heat release of the PCM wallboard increases by 41–78%, and the maximum heat storage and release efficiency is 98%; and (4) at 32 V, the PCM can completely change phase. The theoretical calorific value of the electrothermal film is equivalent to the hourly power generation of 1.45 m2 of photovoltaic modules. The results provide basic data for the integration of photovoltaic and phase change technology and their efficient application in buildings.

Readiness of Malaysian on Sustainable Development in Solar Energy Application

Solar energy is a non-vanishing renewable source of energy that is eco-friendly. However, the solar energy adoption rate in Malaysia remains low due to the low readiness level among the Malaysian. This phenomenon should be emphasized where solutions need to be figured out to encourage the adoption of solar energy in buildings. Thus, this research was conducted to explore the readiness and challenges of the Malaysians in adopting solar energy. A mixed research method was adopted where a totalof 200 sets of online questionnaire surveys were distributed to the public, and a semi-structured interview was carried out to obtain the opinions from the expert in the industry. Based on the findings of the questionnaires, the top 3 challenges in solar energy adoption are (1) high setting up cost of solar panels, (2) limited public awareness of solar energy and (3) efficiency of the solar panel depends on the weather. Next, the qualitative study found that 48.9% of 139 respondents were willing to adopt solar energy in the future. The findings show that that breaking down the barriers of high investment cost and long return investment would further enhance the solar energy adoption rates at the residential scale. Since this study had explored the challenges and solution to these barriers, the outcomes of this study can be used by the policy maker as the fundamental to encourage the adoption of solar energy in the existing buildings where the current adoption rate is low.

Tuning the Solar Performance of Building Facades through Polymer 3D Printing: Toward Bespoke Thermo‐Optical Properties

AbstractFaçades are the primary interface controlling the flow of solar energy in buildings and affecting their energy balance and environmental impact. Recently, large‐scale 3D printing (3DP) of translucent polymers has been explored as a technique for fabricating façade components with bespoke properties and functionalities. Transmissivity is essential for building facades, as the response to solar radiation is crucial to obtaining comfort and greatly affects electricity and cooling demands. However, it is still unclear how 3DP parameters affect the optical properties of translucent polymers. This study establishes an experimental procedure to relate the optical properties of PETG components to design and 3DP parameters. It is observed that printing parameters control layer deposition, which governs internal light scattering in the layers and overall light transmission. Moreover, the layer resolution determines angle‐dependent properties. It is shown that printing parameters can be tuned to obtain tailored optical properties, from high normal transparency (≈90%) to translucency (≈60%), and with a range of haze levels (≈55–97%). These findings present an opportunity for large‐scale 3DP of bespoke façades, which can selectively admit or block solar radiation and provide uniform daylighting of a space. In the context of the building sector decarbonization, such components hold great potential for reducing emissions while ensuring occupant comfort.

Project-based learning for proactive skills development of postgraduate students in solar energy building design digitalisation

PurposeProject-based learning is one of the most effective methods of transferring academic knowledge and skills to real-world situations in higher education. However, its effectiveness is not much investigated focusing on the students' narrative. This study aims at evaluating the students' experience and perspective on adopting project-based learning in master by research and doctoral programmes for proactive skills development.Design/methodology/approachThis study evaluates the self-reflection of 10 postgraduate students and their supervisor who have participated in developing a software tool for solar photovoltaics (PV) integrated building envelope design, management and the related education.FindingsFindings reveal that the students have effectively improved their knowledge on the subject via collaborating with the industry, self-learning/observation, peer learning, problem-solving and teamwork. Dividing the project into student-led tasks has improved the decision-making and leadership skills, risks identification, planning and time management skills. The overall experience has (1) built up confidence in students, (2) enhanced their creativity and critical thinking and (3) improved their proactive skills and context knowledge.Originality/valueA clear research gap can be seen in exploring the effectiveness of project-based learning for master by research and doctoral programmes, which mainly focus on extensive research. These programmes do not necessarily focus on developing students' proactive skills, which is the main requirement if they intend to work in the construction industry. This paper addresses the above research gap by demonstrating the effectiveness of project-based learning for developing the proactive skills in a research-intensive learning environment.

Study on Thermal Storage Wall Heating System of Traditional Houses in Cold Climate Zone of China: A Case Study in Southern Shaanxi

Solar energy has the advantages of being green, renewable, and energy-efficient. The use of solar energy in buildings can result in significant energy savings, and a great deal of practical and theoretical research has been conducted on solar buildings around the world. Southern Shaanxi belongs to a climate zone with hot summers and cold winters (HSCW). The mean room temperature is 4 °C, and it is lower than 2 °C at night, which greatly exceeds the thermal comfort range that the human body can bear. Aiming at a range of challenges including backward heating methods and low heating efficiency in southern Shaanxi, a fully passive thermal storage wall heating system (TSWHS) is proposed for traditional houses in the area. The specific method is to set up a thermal storage wall (TSW) outside the outer walls on the east, west, and south sides of the residential buildings. The wall is provided with an air exchange port, and there is no glass in the outer area of the doors and windows, which does not affect the normal application. The principle is that after the TSW receives solar radiation, the temperature of the internal HDPE (high-density polyethylene) and the air inside the cavity rises, which raises the interior temperature via the heat transfer and the air exchange port inside the TSW. The hot air inside the thermal wall achieves the purpose of heating. Lastly, through a comparison with the original heating system (OHS), it is confirmed that the TSWHS has certain practicability. According to an experimental simulation, the system can increase the indoor temperature by an average of 5.1 °C in winter and save about 1726.43 kWh of energy, accounting for 27.24% of the energy saving.

Use of Polar Heliostats to Improve Levels of Natural Lighting inside Buildings with Little Access to Sunlight.

The growing need to increase environmental and energy sustainability in buildings (housing, offices, warehouses, etc.) requires the use of solar radiation as a renewable source of energy that can help to lower carbon footprint, making buildings more efficient and thereby contributing to a more sustainable planet, while enhancing the health and wellbeing of its occupants. One of the technologies deployed in the use of solar energy in buildings is heliostats. In this context, this paper presents an analysis of the performance of a heliostat illuminator to improve illumination in a classroom at the Campus of Rabanales of the University of Cordoba (Spain). A design of a system in charge of monitoring and measuring daylighting variables using Arduino hardware technology and free software is shown. This equipment develops the communications, programming and collection of lighting data. In parallel, installation of an artificial lighting system complementary to the natural lighting system is implemented. Finally, an analysis of the impact of the proposed solution on the improvement of energy efficiency is presented. Specifically, it is estimated that up to 64% of savings in artificial lighting can be achieved in spaces with heliostatic illuminators compared to those without them.

FEASIBILITY STUDY OF NET-ZERO ENERGY RESIDENTIAL BUILDINGS IN HOT AND HUMID CLIMATES: A CASE STUDY OF IRAN

The use of solar energy in buildings is a good alternative to fossil fuels considering the geographical location of Iran. The present research evaluated the feasibility of net-zero energy residential buildings in southern Iran using a distinct framework. To this end, a low-energy and simulated model of a multi-family residential building as the dominant typology in Bushehr city equipped with combined (active and passive) solutions were used in Design Builder software for optimizing energy consumption. Annual electricity consumption of this simulated model was reduced by 48% using very low power density appliances and an Air Source Heat Pump (ASHP) water heater with an Energy Star label to supply hot water. Then, a grid-connected PV system with a capacity of 29 kW was used to provide the annual electricity demand. The results indicate that this system annually generates 52 MWh of electricity that not only covers the annual electricity demand but also sends 5.8 MWh of additional electricity to the grid. The Economic analysis indicates that the payback period in this project will be very long. Therefore, achieving NZEBs in southern Iran is technically feasible but, from the economic point of view, it depends on the provision of the economic infrastructures.

ESTIMATION OF PHOTOVOLTAIC POTENTIAL AT THE URBAN LEVEL FROM 3D CITY MODEL (SOLAR CADASTER): CASE OF CASABLANCA CITY, MOROCCO

Abstract. Nowadays, the use of solar energy in buildings, especially photovoltaic energy, has undergone a great evolution in the world, thanks to various technological advances and to incentive programs. Related to this topic, the solar cadaster is an important interactive tool to predict the solar potential in an urban environment. The main objective of this research work is to estimate the photovoltaic energy potential of roofs based on aerial photogrammetry and GIS processing. The location chosen for the study is the Maarif district located in the city of Casablanca in order to raise awareness of the public and decision makers to this energy potential through a geoportal that will be developed for this purpose. The tool proposed in this research work makes it possible to evaluate the solar irradiation on a part of the territory of Casablanca with a sufficiently satisfactory precision and reliability, this thanks to the precise reconstruction of the territory in 3D urban model called digital surface model (DSM) at 50 cm resolution by techniques known as photogrammetry which makes it possible to carry out measurements extracted from a stereoscopic pairs, by using the parallax and the correlation between the digital images taken from various points of view. The analysis was used on the basis of specific algorithms and several factors including geographical location, shade, tilt, orientation, roof accessibility and topography which are the main factors influencing the productivity of solar panels.

Comparative Evaluation of Solar Houses Applied in Turkey

The construction sector consumes a significant portion of the energy resources irreversibly and harms the environment. Limited resources and emerging environmental problems have made it necessary to search for new energy resources in the world and in our country, and to use renewable energy sources, environmentally friendly and energy efficient building designs in the building sector. In this context, the issues of solar energy, which is one of the clean and renewable sources and the use of solar energy in buildings, have gained importance. Although Turkey is in advantageous position compared to European countries in terms of potential solar energy, solar energy is not sufficiently utilized in buildings and studies are limited to academic studies. Solar houses, which are built in Turkey in order to benefit from solar energy with active and passive methods in heating, cooling, lighting and ventilation of buildings, consist of single examples designed with different functions. The aim of this study is to emphasize the importance of the use of solar energy in buildings within the scope of renewable energy sources, to examine the solar houses applied in Turkey comparatively and to make suggestions for solar house design.

Life cycle assessment of an ecological living module equipped with conventional rooftop or integrated concentrating photovoltaics

AbstractClimate change is disrupting our environment and business‐as‐usual practices will fail to reverse its impact. This paper focuses on the impact of the building sector and, in particular, it questions the energy and environmental benefits of advanced integrated and more conventional building‐applied photovoltaic (PV) systems, compared to a traditional municipality utility supply. A demonstration project named the ecological living module (ELM) is used to create a comparative life cycle assessment (LCA) of the adoption of these PV systems across three different climatic locations, namely New York City, London, and Nairobi. Findings show that, over the entire life cycle, the solar systems do better than the grid mix in reducing the building's dependence on nonrenewable resources. Unsurprisingly, in comparative terms, these systems do substantially better if the local grid mix is characterized by a predominantly nonrenewable energy profile. When comparing the two solar systems, the environmental impacts of the solar cells are negligible in the advanced system, whereas its structural components result in it being less environmentally friendly than the conventional solar PV. This highlights the possibility of future design iterations of these components to rethink their material ecology in terms of their life cycle—materiality, sourcing, and manufacturing, and so forth. The implications of this work suggest questioning, on a case‐by‐case basis, when and in what contexts integrated solar energy building systems are most plausible. This work also questions the scale at which grid scale distribution should occur.

Passive solar energy building in mountain residence: Strategies and design

Mountain dwellings rely strongly on topographical conditions and are sometimes limited by terrain. A stratega is proposed for a passive solar building design in a Taihang mountainous area to utilize flexibly good sunshine and natural ventilation for the building and to organize a shady courtyard next to the mountain to form a cold source of the outdoor environment. This design has made a positive attempt for the application of passive solar building strategies to mountain dwellings.

CFD analysis on heat transfer in a building wall using Phase Change Materials (PCM)

Environmental conditioning is now a critical factor for modern day keeping the temperature inside the buildings in a safe state using the air-conditioner. Phase change materials promise innovative materials that are used inside the building to build wall for cooling. The current work is aimed at managing the thermal transfer in buildings using PCM materials and controlling the transfer of heat from various states to store the energy and use it later. A PCM storage medium filled with a variety of PCM panels was developed and tested using the ANSYS Fluent simulation of computational fluid dynamics. In this paper the PCM is purposely designed between the roof and concrete wall layer for energy gains in thermal systems to storing solar energy in buildings. The experiment was conducted using 3D model designed per mass unit within a small temperature range using CFD analysis. Numerical model displayed effective similarity with experiment; hence the model can be used as energy storage unit under different configurations for performance evaluation of the building system. The specific heat, viscosity, heat conductivity, temperature and total energy has been evaluated using the linear method available using CFD Fluent. Majorly the result considering depends on the thickness, inlet cooling temperature and mass flow rates.