Horizontal Shading Research Articles

Analisis Prestasi Terma Penghadang Suria Luaran Sedia Ada di Kampung Admiralty, Singapura

External Solar shadings have long been designed as an integral part of a building’s facade for functional, aesthetic and privacy reasons. From a functional aspect, it is used to reduce heat and glare, thus helping to improve the thermal as well as lighting quality of the building. In a tropical climate, the yearlong sun radiation, especially those facing the eastern and western building facades with large glazed surfaces may show severe thermal and glare discomfort issues. This paper analyses the impact of the existing shading system of the vertical and horizontal fins and green facades of The Admiralty Village building in Singapore. A thermal imaging camera was used to detect thermal readings from all of the facade’s shading systems. From the result comparison, each facade of the building requires a different shading treatment due to the different sunlight angles. The south facade is best shaded with horizontal shading. East and west facades require shading that blocks sunlight entering at low angles. The north facade can be left unshaded. Green walls with highly dense vegetation perform more effectively than thermal insulation in reducing the cooling load of the building. This study further convinced the need for solar shading devices, especially in the southern facades of tropical countries.

Designing energy-efficient and visually-thermally comfortable shading systems for office buildings in a cooling-dominant climate

Windows and their control elements, including shading systems, are among the most critical building components affecting both energy consumption and occupant comfort. With the increasing demand for full-glazed facades, designers and researchers are actively devising advanced control strategies to address the challenges posed by excessive sunlight penetration and heat transfer. These strategies aim to harmonize the benefits of natural light with the need for comfortable indoor environments and energy consumption reduction. This study investigates the impact of external shading configurations for an office room in Tehran, categorized as group B in the Köppen climate classification, to reduce total building energy consumption and improve occupant thermal and visual comforts. The shading parameters include shading angle, shading depth, and the number of shading slats. More specifically, this study analyzes and compares two design configurations for the considered office room. The first configuration consists of a single southern window with horizontal shading, whereas the second configuration consists of two windows on the south and west, one being horizontal shading on the southern side and the other being vertical shading on the western side. There are a total of 1330 models investigated from which 20 models are selected as the most suitable solutions. Finally, this paper examines the effect of each design parameter on the overall performance of each configuration in terms of energy efficiency and visual-thermal comfort.

Daylight Performance of Integrated Horizontal Light Pipe with Shading Devices (Validation) for High-Rise Building in Tropical Climate

Daylight is known to bring benefits to human in terms of productivity, psychology, and physiology. The emergence of deep plan layout in high-rise hinders the utilisation of the abundance daylight available in tropical climate. This brings challenges to ensure a uniform distribution in the interior room. This study focuses on the software validation of the integration of a horizontal light pipe (LP) and shading devices (SD) to illuminate the deep plan where the former provides daylight in the deepest portion of the room while the latter helps to shade the excessive daylight at the window opening. The shading devices that have been chosen are overhang, light shelf, and blinds. The computer simulation, Integrated Environment Solution: Virtual Environment (IESVE), is being validated with physical model experiment with a scale of 1:10. The experiment was conducted in an open carpark in Universiti Sains Malaysia, Penang, Malaysia from 9am to 3pm for two days. The validation was done using graph comparison, Pearson Correlation, relative root mean square error (RRMSE), and relative mean bias error (RMBE). The results shows that the daylight ratio (DR) from the software has positive relationship with the experiment data. Hence, the software can be used to further simulate various integration of LP and SD.

The Effect of Shading Devices on OTTV (Overall Thermal Transfer Value) Value of Office Buildings: Case Study of PT Industri Kapal Indonesia (IKI) Building

One of the passive design strategies that effectively reduce the heat load on the building envelope, especially in areas with a large surface area of glass shading Device. The research aims to measure the design influence of shading devices against the value of Overall Thermal Transfer Value (OTTV) buildings. Research using quantitative methods, research done by trying Shading devices with Vertical Models, Horizontal multiple fins, and Egg crates, which have the length and slope provided by the Indonesian National Standard SNI. It tests each design shading measured on an impairment basis OTTV the best and best under 45 Watt/m². The results of the study show that shading devices affect the impairment of OTTV. The longer the shading device and the higher the slope, the more effective it is in blocking incoming radiation through the glass surface. Impairment OTTV existing buildings without a shading device have an initial value of 69.572 W/m2, decreased by 55% to 31.57 W/m2. Shading an egg crate with length120 cm with a slope of 40° is the best shading based on a comparative analysis between vertical louver shading and horizontal multiple fin shading. This is due to shading egg crates being able to respond to the sun in incoming low and high altitude angles to minimize or block radiation that enters through the glass surface.

Influence of Transparent Envelope Parameters on Office Building Energy Use Intensity in the Different Thermal Climate Regions of China

The role of the transparent envelope in energy savings is crucial as it accounts for a significant proportion of the total energy loss (between 30 and 40%). This paper focuses on the identification of reasonable parameters for the transparent envelope in different climatic regions. To achieve this goal, typical urban office buildings from four different climatic regions are used as research objects. A total of 1600 scenarios were simulated to investigate the variation of energy use intensity, including transparent envelope parameters, meteorological parameters and different types of glazing. The results show that for south-facing transparent envelope facades, type D glazing is the most energy efficient in severe cold regions, type C in colder regions and type B in the other two climatic regions. No solar shading is required in the very cold region. Horizontal shading can be an effective method for saving energy in colder climates, while comprehensive shading can be beneficial in other regions. Deep shading is particularly energy efficient if it meets lighting requirements. For example, in Guangzhou, energy savings of 13.46%, 15.47%, 7.01% and 7.02% can be achieved in the east, west, south and north directions, respectively, using B-type glazing and a comprehensive shading depth of 900 mm.

Prediction of Cooling Load of Tropical Buildings with Machine Learning

Cooling load refers to the amount of energy to be removed from a space (or consumed) to bring that space to an acceptable temperature or to maintain the temperature of a space at an acceptable range. The study aimed to develop a series of models and determine the most accurate ones in the prediction of the cooling load of low-rise tropical buildings based on their basic architectural and structural characteristics. In this context, a series of machine learning (regression) algorithms were tested during the research to determine the most accurate/efficient prediction model. In this regard, a data set consisting of ten features indicating the basic characteristics of the building (floor area, aspect ratio, ceiling height, window material, external wall material, roof material, window wall ratio north faced, window wall ratio south faced, horizontal shading, orientation) were used to predict the cooling load of a low-rise tropical building. The dataset was generated utilizing a set of generative and algorithmic design tools. Following the dataset generation, a series of regression models were tested to find the most accurate model to predict the cooling load. The results of the tests with different algorithms revealed that the relationship between the predictor variables and cooling load could be efficiently modeled through Histogram Gradient Boosting and Stacking models.

Validation of IES-VE for Assessing Daylight Performance of Building Implementing Horizontal Light Pipe and Shading Systems in the Tropics

Abstract. Various daylight simulation tools, which are rapidly developed, become a reliable way for simulating the complex daylighting environment. Empirical validation of the daylight simulation tool is essential in determining its reliability, especially in simulating light transport and shading system in the Tropics. Distinct from previous research, the validation involves Horizontal Light Pipe (HLP), a side window with shading systems in different room aspect ratios and orientations. This study aims to validate the simulation results of Integrated Environmental Solutions-Virtual Environment (IES-VE) Radiance IES with the measurement results of physical scaled models for evaluating HLP, light shelves, and blinds' daylight performance under intermediate and overcast sky conditions. Two physical scaled models 1:10 represent office rooms with HLP and shading systems with different room aspect ratios were constructed. Daylight Factor (DF) and Daylight Ratio (DF) of physical scaled model measurement and IES-VE simulation were compared. The results showed that under intermediate and overcast sky conditions, the Pearson correlation between simulation and measurement results using DR and DF was strong, significant, and positive, as high as 0.84 and 0.80, respectively. The Mean Bias Error between simulation and measurement results under intermediate and overcast sky conditions were -12% and -7.7%, respectively. IES-VE is reliable to evaluate the HLP and shading systems' daylight performance with different room orientations in the Tropics.

Applying expanded metal mesh for outdoor shades in outdoor thermal environments.

This study investigated the applicability of expanded metal meshes (EMMs) in horizontal shading devices. We performed simulations and experiments with EMMs with different opening ratios and directions. We established various experimental and control groups to measure air temperature, surface temperature, and black globe temperature. After the comparison of simulation and experimental data, we used Grasshopper to simulate long-term climate situations. The research results can serve as reference for users in Tainan and provide customized suggestions. The findings can serve as a paradigm for parametric design to analyze EMMs. In design projects involving outdoor horizontal shading devices, these results can be used in the design phase for evaluation. Full-day measurements revealed that EMMs with small openings exhibited favorable shading effects. In the Tainan area, we suggest using north-facing EMMs; in our simulations result, 70% of sunshine did not pass through the mesh in a day. For shading equipment in the morning, west-facing EMMs should be used because they blocked 50-90% of sunshine. For recreational areas in the afternoon and evening, east-facing EMMs can block 50-90% of sunshine after noon. In Taiwan, south-facing EMMs are not advised because their shading performance is suboptimal in the morning and afternoon.

Experimentation of MPPT Control Driving a Buck Converter with PV Module Disturbances and Variable Load in a Nanogrid

The objective of this paper is to perform a laboratory test on the performance of MPPT control in a nanogrid. The components used for tests are described, namely (i) a PV module SPP031001200 manufactured by Victron energy, a prototype of a synchronous buck converter controlled by Arduino Atmel ATmega V-2560, and a DC electronic load programmable 72-13210 manufactured by TENMATM. Among several MPPT controls, the choice falls on the methods Perturb and Observe “P&O” and Increment of the conductance “INC” which are more widely used than others. Laboratory tests with different PV module conditions and variable output voltage were performed. In full sunlight, the input power of the buck converter gives a better result with the INC method compared to the P&O method. For a PV module exposed to horizontal or vertical total shading, INC method gives a small advantage compared to the P&O method, which can be beneficial for a long time. Compared to the P&O method, INC method always gives better results due to its more complex algorithm. Due to the lack of measuring instruments, the different tests were performed without considering irradiance and temperature.

Thermal Performance of Horizontal Fixed Sun Shading Device

Earlier investigations on passive cooling methods applied software modelling, and the findings were not confirmed through field measurement. Hence, this study applied a stationary experiment on a real structure and weather conditions employing horizontal sun shading (SDH). The purpose of this study was to compare the performance of fixed passive sun-shading devices put on to the bare façade of three-story terrace shophouses in Malaysia. The experiment findings revealed that SDH significantly improved the internal thermal environment by lowering the average monthly indoor air temperature (Ta) by 0.98 K and the peak temperature by 2.11 K. SDH is also effective during the warmest sunny days, lowering 1.23 K on average for the day. Meanwhile, SDH reduced the temperature in the control room by 5.40 K during the warmest peak time.When it came to indoor mean radiant temperature (Tmrt), SDH performed better than the control room in the very hot peakover a month (2.38 K) and on the highest temperature of the day (7.70 K). Finally, it can be inferred that SDH worked better from late at night until early in the morning, cooling the room temperature faster. This quiescent choice is one of the best for enhancing a building's internal thermal performance while also possibly contributing to a decrease in operational energy consumption.

IMPACT OF WINDOW SHADING ON THE THERMAL PERFORMANCE OF RESIDENTIAL BUILDINGS OF DIFFERENT FORMS IN JORDAN

Introduction: Window shading is considered one of the most effective passive design approaches that improves indoor thermal performance, minimizing the usage of HVAC and reducing energy consumption. Purpose of the study: We aimed to investigate the impact of external window shading on thermal performance of three existing residential buildings having different forms (rectangular, L-shaped, and U-shaped) in hot-dry climate in Amman, Jordan. Methods: Three types of shading, namely: vertical, horizontal, and combined, of different lengths (0.75 m, 1.00 m, and 1.25 m) were introduced to the existing buildings. The effect of those types of shading was studied using the OpenStudio SketchUp 2020 plugin and EnergyPlus simulation program. Results: It was established that vertical shading slightly improves the indoor air temperature in all building forms, while horizontal shading and combined shading improve the thermal performance of buildings to a more significant extent. Combined shading of 1.25 m in length shows the optimum behavior in all buildings since it reduces the indoor air temperature in the range of 2.6–3.3°C. Besides, it improves thermal sensation, which seem to be closer to the comfort zone, by reducing the predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD) values as compared with the baseline situation without shading. In addition, the rectangular building demonstrated the best response for shading by showing the largest reduction in the indoor air temperature.

MULTIOBJECTIVE OPTIMIZATION OF THE INTERGENERATIONAL RESIDENTIAL SPACE WITH THE GOAL OF DAYLIGHTING AND THERMAL COMFORT

ABSTRACT (1) Background: An ageing population and two-child policy have led to the transformation of China’s family structure, and multigenerational residences account for an increasing proportion of mainstream family residences. Different generations of residents have great differences in behaviour patterns and health requirements, but existing residential buildings are not especially designed for health needs. (2) Methods: First, based on relevant codes and a questionnaire survey, the spatial needs and behaviour patterns of different generations of residents are obtained, and the benchmark model is established based on the Grasshopper (GH) parametric platform. Then, based on the GH platform and the building simulation plug-in, which are Ladybug Tools and a multiobjective optimization tool named Wallacei, daylight autonomy (DA), useful daylight illuminance (UDI), and the proportion of thermal discomfort hours (PDH) are taken as daylighting and thermal comfort indicators, and the bedroom location, orientation, bay size, depth to bay ratio, window form, window-to-wall ratio, and horizontal shading width are optimized. Finally, the Pareto front is analysed by the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) comprehensive evaluation method, and the optimal solution is compared with existing multigenerational residences in Tianjin. (3) Results: First, the middle room, oriented south or south by east, large bay, small window-to-wall ratio, and bay window can effectively be improved for indoor thermal comfort, while rooms that are oriented south or south by east, small depth bay ratio, large window-to-wall ratio and balcony can effectively be improved for daylighting quality. Second, compared with existing buildings in Tianjin, the DA, UDI, and PDH of the adult bedroom with the ideal solution are increased by 33.7%, 3.5%, and 10.8%, respectively; the DA, UDI, and PDH of the child bedroom with the ideal solution are increased by 15.5%, 4.2%, and 4.9%, respectively; and the DA, UDI, and PDH of the elderly individual bedroom with the ideal solution are increased by 42.7%, 4.9%, and 1.7%, respectively. (4) Conclusions: The optimization scheme is substantially improved for the health of the indoor daylight and thermal environment of existing housing, and it provides a scientific and quantitative decision-making basis for the healthy design of multigenerational residences.

How does future climatic uncertainty affect multi-objective building energy retrofit decisions? Evidence from residential buildings in subtropical Hong Kong

Energy consumption of and carbon emissions from buildings, which substantially depend on outdoor climate conditions, may be susceptible to future climate change. However, how future climatic uncertainties affect decision-making regarding building energy retrofits is unclear from the life-cycle analysis perspective. This study used typical high-rise public rental housing buildings in subtropical Hong Kong as a case study to consider future climatic uncertainties under representative concentration pathway scenarios and in different general circulation models to estimate their effect on multi-objective building retrofit decisions considering trade-offs among different objectives, namely, life-cycle economics, life-cycle carbon emissions, and operational energy use impacts. The results indicate the significant influence of future climatic uncertainties on the optimal values of building energy retrofit measures. The passive house infiltration standard and thick (0.06–0.1 m) polyurethane foam insulation can be recommended for long-term future climatic conditions (RCP8.5–2065s). By contrast, optimal values of glazing materials, horizontal shading projection factors, and window-to-wall ratio are not susceptible to future climatic uncertainties. Uncertainties from different general circulation models are another notable factor affecting optimal values and retrofit options. This study reveals the importance of considering future climatic uncertainties when deciding optimal values and selecting building energy retrofit options.

Optimization of an office building form using a lattice incubate boxes method

With the increasing demand for sustainable built environments, energy performance is becoming essential in the early design stage. Several previous studies using optimization of building form for energy performance considered simple hypothetical forms. In addition, previous multi-objective optimization (MOO) of building form and envelope did not consider views percentage to the outdoor (VPO) despiteof its importance for human mental health and its conflict with energy performance. This paper proposes a novel lattice incubates boxes (LIB) method that optimizes a cellular office building form. It considers the entire building with 27 thermal zones in an attempt to mimic a real case study. In addition, it considers VPO as an objective in the MOO of building form and envelope. First, the study performs single-objective optimization (SOO) of architectural form and orientation for annual thermal Energy Use Intensity (EUI) in Cairo, London, and Chicago. Second, it performs multidisciplinary MOO of Cairo’s form, window to wall ratio (WWR) and horizontal shading devices (HSD) for annual thermal EUI, annual Useful Daylight Illuminance (UDI-100–2000), and VPO. Third, it develops the LIB method to make it more applicable in professional practice through considering 72 individual thermal zones while adding more constraints. Compared to the initial forms, first part EUI savings were between 16.86% and 12.9 %. EUI, UDI, and VPO savings for Cairo in the second part were 20.16%, 11.5%, and 19.5 %. Scatterplots are developed for the second part that show rows motion has the highest positive impact on UDI and VPO, WWR has a positive impact on all objectives and HSD has high positive impact on EUI only. Savings in the third part are 11 % EUI, 8.77 % UDI, 2.86% Daylight Autonomy (DLA) and 7.8 % VPO. Scatterplots in the third part show that almost all proposed form dynamic parameters have strong impact on all objectives.

Effect of Horizontal Shading Device Towards Daylighting in Lecture Room at Administration Building, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia

Daylighting plays a crucial role in making the lecture room comfortable, particularly in terms of vision. Additionally, by lowering reliance on artificial lighting, it eases the load of electricity use. However, windows made of transparent glass let most of the sunlight inside, which degrades the visual clarity and causes glare. Therefore, strategies for limiting daylighting entry are crucial to solving the issue. One of the techniques is the use of window overhangs, including egg-crate, horizontal, and vertical forms. However, the utilisation of solely horizontal types of overhang is the exclusive subject of this study. In this study, the lighting in existing lecture room was analysed, and the impact of projections on the quality of lighting in lecture room was also looked at. This study employed the lecture room at the Faculty of Engineering and Built Environment (FKAB) known as the Seminar Room as a case study. The space is typically utilised for giving lectures as part of educational activities. Field measurements and simulations with Sefaira software were the methods employed for data collecting. By contrasting data from the simulations and field observations, the simulation software was also validated. According to the study, lecture room in the FKAB Administration Building are less successful when using a single horizontal window overhang. It is possible to contribute to a more sustainable building design with better daylight discoveries, especially for learning and teaching, by researching the most efficient horizontal projection ratio.

Sustainability and efficient use of building-integrated photovoltaic curtain wall array (BI-PVCWA) systems in building complex scenarios

Photovoltaic Curtain Wall Array (PVCWA) systems in cities are often in Partial Shading Conditions (PSCs) by objects, mainly neighboring buildings, resulting in power loss and even hot spot effects. Changing the topology of the PVCWA system can effectively reduce the losses caused by PSCs. However, current studies rarely consider the annual optimal topology as a whole. Therefore, this paper develops and validates a power model for PVCWA in building complexes, using the model to simulate the power generation of Series(S), Parallel(P), Vertical-Series-Parallel(V-SP), Horizontal-Series-Parallel(H-SP), Vertical-Total-Cross-Tied(V-TCT), and Horizontal-Total-Cross-Tied(H-TCT) arrays in different cities and different surrounding building heights. The results show that the power generation performance of each topology of PVCWA in a building complex varies in real time. With the same building layout, the geographical location has less effect on the power generation ranking of different topologies of PVCWA, but it affects the power generation gap of different topologies. And the surrounding building height affects the shading characteristics of the shaded PVCWA system. H-SP and V-TCT arrays can mitigate the effect of horizontal shading more effectively, while V-SP and H-TCT arrays can mitigate the effect of vertical shading more effectively. This research can provide a basis for the application of PVCWA systems in buildings.

The Use of Horizontal Shading Devices to Alleviate Overheating in Residential Buildings in the Severe Cold Region and Cold Region of China

Global warming is resulting in higher summer indoor temperatures in the severe cold region and cold region of China, and this is affecting thermal comfort. Local building design codes consider these regions as cool in summer, and do not consider the phenomenon of overheating or propose countermeasures. This paper studied the possibility of overheating in residential buildings in these areas. It suggested alleviating this phenomenon using external horizontal shading, and discussed how to integrate thermal comfort into the building design and save energy consumption. The IESVE software was used to simulate 18-storey residential buildings with natural ventilation in Yichun, Harbin, Shenyang, Dalian, and Beijing, and to calculate the change in indoor operative temperature. Horizontal shading was designed for case study building to attempt to alleviate the overheating phenomenon in summer. The results showed that the case study building in the five cities experienced different degrees of overheating. External horizontal shading was successful in reducing indoor overheating, especially in the severe cold B and C zones and the cold A and B zones. The relevant building codes should be modified to take this into account. Reasonable design of horizontal shading can effectively reduce energy consumption, particularly when compared with air-conditioned buildings.

Studying the influence of shading devices on indoor thermal comfort in desert and Mediterranean climates

Thermal comfort is regarded as the most important issue in residential buildings. To verify the thermal performance of the envelope components used for the promotional apartments in Algeria, whether they are adapted to the hot and dry southern climate, or the Mediterranean climate, and to understand the effect of fixed and combined horizontal and vertical shading devices of different dimensions (12 cm, 25 cm, and 50 cm) on the indoor thermal comfort of these apartments, two main climatic zones have been considered in this study, the first is a desert climate of (Biskra, Ghardaïa, and Ouargla), while the second is a Mediterranean climate of (Algiers, Oran, Bari, and Naples). The methodology of this research was based on a comparative approach to the outcomes of a stay in an apartment in Biskra, which was looked at as a model for other desert and Mediterranean cities, based on the operative temperature data of different scenarios obtained through several simulations, which conducted by the use TrnSys software. The findings suggest that the double-walled hollow brick envelope causes a very severe indoor thermal environment (To<29) in dwellings located in desert regions such as Biskra, Ghardaïa, and Ouargla. In addition, the findings also suggest that shading devices are more effective for apartments located in the Mediterranean region (Algiers, Oran, Bari, Naples) than those located in the desert region. In the desert region, the use of mechanical cooling devices in the summer period is considered the most adequate solution to ensure the occupants’ thermal comfort. To identify the most optimal shading device models, future research based on the parametric simulation of kinetic shading devices is needed.

An evaluation of shading device in tropics utilising the sun-path diagram

Sun orientation plays a significant role in architectural design. Concerning this, the sun-path diagram is a tool for developing more knowledge to improve the quality of building design. For achieving good and thermally comfortable building design, the sun shading device is essential to work. Therefore, this study performs an evaluation of the shading device in tropics utilising the sun-path diagram. This study evaluates the horizontal, vertical and louvre shadings on eight wind directions in Banda Aceh as a case study in tropics by adopting shadow angle protractor for superimposing the vertical (VSA) and horizontal shading angle (HSA) on the stereographic sun-path diagram to indicate the shadow and daylighting time. The result of this study proposes the suitable type of shading and the acceptable depth of horizontal shading dimensions for all of the orientations of the wind directions.

Integrating Daylighting with Task-Ambient Lighting for Enhanced Energy Savings in Office Spaces

Daylighting has been widely studied as a fundamental aspect of spatial illumination and energy efficient façade design. Effective installation and control of shading devices diminishes the adverse effects of prevailing climatic conditions on building envelope performance and reduces resultant lighting and cooling energy consumption. Task-ambient lighting as a free-standing approach has also been proven to reduce lighting energy consumption compared with typical general ambient lighting. This study estimates the energy saving potential of integrating daylighting through fixed external horizontal shading slats with task lighting. Spot measurements were taken in a test room to validate a daylight calculation program. Full year indoor work plane daylight simulations were performed for office spaces of different floor areas and varying window to wall ratios. Indoor daylight quality was assessed using the Useful Daylight Illuminance metric and three different task lighting schemes explored. Lighting energy savings of 10% to 90% were estimated under the three schemes in comparison to similar office spaces with common unshaded heat reflective glazing.