Study of Indoor Lighting Uniformity with Revolving Light Shelf

Study of Indoor Lighting Uniformity with Revolving Light Shelf | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Study of Indoor Lighting Uniformity with Revolving Light Shelf muhammad sega sufia purnama This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6708002/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Light shelf is one of the devices to help the penetration of light into the building. Research discussing the light shelf starting from the shape, position and variations have been conducted to maximize its performance. Most of these variations are in a static state even though the sun has movement throughout the day. While numerous studies have explored light shelf configurations, there is a lack of research on the dynamic adjustment of light shelves in response to changing angles, particularly in tropical climates The primary objective of this study is to investigate the effectiveness of a revolving light shelf in enhancing indoor lighting uniformity in tropical climates. The method used in this research is computer simulation with Dialux Evo 8.2 software. The results indicated that after analyzing and selecting the best angle based on the Lighing Uniformity value and average light intensity, it can be seen that there is a pattern in each orientation. Judging from the efficiency of light shelf movement, the south side has the least movement, which only moves from 30 0 to 45 0 . The most movement is on the west side light shelf.. Architecture, Design and Planning lighting uniformity revolve daylight light shelf Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Natural lighting is essential in a building [1]. The benefits obtained by users in addition to illuminating activities in the room can also be for health functions [2]. Another advantage is that the source is unlimited. Nowadays, the use of transparent facades allows more light to penetrate the building [3]. But too much light intensity can cause glare [4]. Sunlight also contains heat so the intensity needs to be reduced when entering the room [5]. In tropical climates, the sunlight continues to shine throughout the year with high intensity [6]. This requires buildings to be adapted so that users feel comfortable inside. One of the architectural elements exposed to direct sunlight is the façade [7]. Nowadays, with the development of technology, many facades use transparent fields as coverings [8]. Natural lighting becomes easier to enter the space. The adverse effect is that sunlight with high intensity will directly enter and heat the space [9]. This results in a significant amount of energy to cooling the space. On the other hand, covering the facade with a ratio of more massive areas than transparent areas will reduce the intensity of incoming light [10]. Many studies have been conducted on the topic of daylighting. In particular, it discusses how to let light into a building without making the entire facade transparent. Light Shelf (LS) is one strategy to let light into a building [11]. By definition, LS is the addition of horizontal slats to the window plane that function to reflect sunlight towards the ceilling so that the reflection is expected to illuminate the floor of the room more deeply [12]. The position of the slats can be horizontal or angled [13]. The placement can be in the room, between and outside the room [14]. configuration of shapes and geometries has been done by many researchers [15]. The addition of solar cells [16], mirrors [17] and even shading [18] has been carried out to improve LS performance. Some performance parameters of LS that are usually used are useful daylight illuminance [19], LU and glare [20]. LS can be used in static or dynamic state. Static state, the performance of LS is maximized when certain conditions are met. This led researchers to change LS from static to dynamic state. After the research, it turned out that dynamic LS performed better than static conditions [21]. In relation to energy, dynamic LS requires a power source to move. Although they can be moved manually, it is usually difficult to move them precisely to maximize their performance. While numerous studies have explored light shelf configurations, there is a lack of research on the dynamic adjustment of light shelves in response to changing angles, particularly in tropical climates The primary objective of this study is to investigate the effectiveness of a rotation angle of light shelf in enhancing indoor lighting uniformity in tropical climates. Methodology This research was conducted using a quantitative approach [22]. Measurements of average light intensity and lighting uniformity were carried out by simulating [23] the room model in Dialux Evo 8.2 software. The first step in this research is to determine the area of space to be observed. The model is an experimental room located in Jakarta with 5m length, 5m width and 3m height [24, 25]. Square area is common in recent lighting research to prevent changing in depth of sunlight penetration [26]. Jakarta is selected because it is located in tropic region. Abundant with sunshine all year round but not well utilized [27]. The model is given a window with a size of 4m x 1m with a window height of 1.8m [28]. With a window area of 4 m2 and a wall area of 15 m2, the windows wall ratio of the facade is 26% [29]. The windows wall ratio (WWR) is not 100% because the model is located in the tropics, so the WWR must be adjusted to avoid glare or excessive natural lighting [30, 31]. The model will be made as many as 4 pieces with window orientations facing east, west, north and south. There is only one window per orientation. The next step is to add LS to the window. In this research, the interpane position is chosen for ease of rotation so as not to burden the motor due to heavy loads. 4 models will be given LS with a width of 1m, a length of 4m and a slope of 0 0 . Data collection time is taken at 8am, 10am, 12pm, 2pm, 4pm. Under cloudy sky conditions on September 21, 2024. After data collection, the inclination of the LS was changed to 15 0 towards the inside of the space with the rotating axis in the center, and then the simulation was performed again. Next, simulations were conducted for angles of 30 0 and 45 0 . From previous research, the function of LS can also be for shading. It protects the interior of the space from glare and direct sunlight. So, in this research, the angle of LS is also rotated out of the building by 15 0 and 30 0 to provide shade. Results The simulation results are LU values with numbers between 0 and 1. 0 indicates the absence of uniformity in the room while values closer to 1 indicate a more even lighting distribution. Because of this, it is inevitable that the average illuminance in a room that meets the lighting standards can have a low LU. One reason for this is the presence of direct sunlight which makes the average illuminance high but nonuniform. On the other side, when a room has a low average light intensity, the LU value can be more than 0.5. This is because LU only calculates the lowest light intensity value divided by the average light intensity, so when a room has a low light intensity, the difference between the average and the smallest value is not so significant. The obtained LU value will determine the angle to be taken as the LS movement. A table will be created based on the orientation so that it can be known, the best angle at that orientation and time. The amount of light intensity in the simulation results can be used as a consideration for choosing the angle of LS motion Table 1 Value of LU in East Orientation East 8am 10am 12pm 2pm 4pm 0 0.24 0.38 0.43 0.42 0.43 15 0.14 0.35 0.14 0.43 0.38 30 0.10 0.32 0.35 0.40 0.43 45 0.13 0.27 0.24 0.30 0.31 -15 0.49 0.48 0.46 0.52 0.52 -30 0.56 0.54 0.64 0.57 0.53 In the table, we can see that the cells are colored gray. This color indicates the LU value selected as the reference for the LS motion. The consideration for selecting the LU value is not based on the highest value but also on the average indoor lighting intensity. When the LU value is high but the average indoor lighting is low, it is not chosen. Since in this experiment, the use of indoor light is purely using daylight, the office lighting standard of at least 300 lux will be reduced by 30%, which is at least 210 lux. This percentage value is taken because the existing standard requires artificial lighting. In this experiment, no artificial lighting was used. In the east orientation it can be seen that at 8am, the outward movement of LS by 15 0 is able to create an LU value of 0.49. An LU value of 0.56 is not selected because the average light intensity is below 300 lux. At 10am, the inward movement of 15 0 to 0 0 makes the room have an LU value of 0.38. if the LS does not rotate, the LU value is high but the average light intensity decreases. At 12pm, the LS rotates inward by 45 0 . resulting in an LU value of 0.24. At 2pm, the LS must rotate outward by 15 0 to 30 0 . this rotation results in an LU value of 0.40. At 4pm there is a decrease in performance both rotating inward and outward so the LS does not need to rotate and the LU value becomes 0.43. Table 2 Value of LU in West Orientation West 8am 10am 12pm 2pm 4pm 0 0.45 0.41 0.42 0.42 0.17 15 0.39 0.35 0.40 0.35 0.11 30 0.40 0.41 0.35 0.35 0.12 45 0.28 0.26 0.24 0.26 0.13 -15 0.60 0.56 0.52 0.53 0.32 -30 0.78 0.69 0.68 0.45 0.56 In the west orientation, at 8am, the selected LU value was 0.40 at the angle of 30 0 . The LU value at the angle of 0 0 was larger at 0.45 but was not selected due to the low intensity result below 100 lux. At 10am, the LS position remained at 30 0 with LU of 0.41. When LS rotates to another angle, there is a decrease in LU value and average light intensity. At 12pm, there was no need for rotation as the LU value was 0.35. The 0 0 angle produced a higher LU value of 0.42 but the average light intensity was low. At 2pm, LS rotated outward by 45 0 and obtained an LU value of 0.53. At 4pm, LS rotated back outward to 15 0 making the LU value 0.56. At 2pm - 4pm, the intensity of direct sunlight is very high resulting in glare. This also results in a low LU value. Table 3 Value of LU in North Orientation North 8am 10am 12pm 2pm 4pm 0 0.35 0.38 0.38 0.37 0.37 15 0.32 0.31 0.40 0.33 0.30 30 0.32 0.32 0.33 0.29 0.34 45 0.28 0.26 0.24 0.26 0.28 -15 0.45 0.52 0.43 0.45 0.48 -30 0.59 0.67 0.47 0.50 0.62 The north side is different from the east and west sides. This is because the facade is not exposed to direct sunlight. The effect is that the LS on this side reflects more sky light than direct sunlight. The average value of light intensity in the space is also more stable than the other 2 sides. At 8am, the LS rotates 30 0 inward with a LU value of 0.32. At 10am, rotation is not yet necessary because the LU value is still at 0.32 but the average intensity rises by almost 100 lux. At 12pm, the LS had to rotate 15 0 inward to 45 0 to keep the light intensity above 300 lux with a LU value of 0.24. At 2pm, the LS rotated 30 0 inward. The LU value obtained is 0.33. At 4pm, LS rotates outward by 15 0 . this is to get LU of 0.34. Table 4 Value of LU in South Orientation South 8am 10am 12pm 2pm 4pm 0 0.39 0.37 0.45 0.37 0.36 15 0.29 0.32 0.40 0.33 0.33 30 0.32 0.31 0.37 0.31 0.35 45 0.28 0.27 0.26 0.27 0.29 -15 0.50 0.44 0.52 0.52 0.44 -30 0.53 0.64 0.66 0.61 0.60 The south side at 8am rotated LS by 30 0 making the LU value 0.32. At 10am, no rotation was performed as the LU value was 0.31. At 12pm, a rotation of 15 0 was performed which did not significantly increase the LU value of 0.26. At 2pm, an inward rotation of 15 0 resulted in an LU value of 0.31. At 4pm, no rotation was required as the LU value was 0.35. After analyzing and selecting the best angle based on the LU value and average light intensity, it can be seen that there is a pattern in each orientation. On the east side, the initial rotation is not inward but outward. This is due to the presence of low-angle direct sunlight. The inward rotation of the LS will result in the sunlight entering more easily because the direction of incoming sunlight is parallel to the slope of the LS. However, if the rotation is outward, then indirectly, the LS functions as a shade and because the angle of incidence of sunlight is low, the rays are able to be reflected into the space further and eventually get a high LU value. in some point. The east side in the afternoon to evening, has a decrease in light intensity due to its farther distance from the sun. This results in less effective LS rotation. The west side is the opposite of the east side. If in the morning it is the east side that needs shading, then in the evening, it is the west side that needs it. The LS rotating outward is more effective for the dual function of shading and LS. The north and south sides do not require outward rotation. This is because there is no low angle of sunlight so the outward rotation actually results in low latitude of sunlight. Furthermore, south orientations tend to benefit more from light shelves, as they can effectively diffuse direct sunlight and create a more balanced lighting environment [32, 33] From recent study, LS can decrease the uniformity of illuminance but this problem can be solved with revolving LS [34, 35]. The finding of this study also confirms that. There is an acknowledged that light shelf with additional technology like dimming control or self-awareness can make performance of LS better [36]. This study can be continued by doing simulations on other dates so that the best angle for LS movement in a year can be obtained. Conclusion From the experiments that have been conducting, it can be seen that the placement of LS in each orientation with a given rotation will produce different LU values every hour. The best LU value is obtained on the east side with an outward rotation of 15 0 then a maximum inward rotation of 45 0 . For the west side, the rotation starts from the inside out. The best LU value is obtained when the LS rotates 30 0 inward and then outward by 30 0 . The north side gets the best LU value when the LS can rotate in the range of 15 0 to 45 0 inward. The south side gets the LU value according to the standard by rotating in the range of 30 0 to 45 0 . Considering the efficiency of LS movement, the south side has the least movement, only moving from 30 0 to 45 0 . The most movement is on the west side LS. Declarations Competing Interests The author(s) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. References S. Krasić, P. Pejić, P. Mitković, Significance of daylight in the design and construction of buildings. Gradjevinar. 65, 833–840 (2013). M. N. Mead, Benefits of sunlight: a bright spot for human health. 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Ghiabaklou, Investigating the influence of light shelf geometry parameters on daylight performance and visual comfort, a case study of educational space in Tehran, Iran. Buildings . 6 (2016), doi:10.3390/buildings6030026. P. Baten, Md. A. R. Joarder, (The International Institute of Knowledge Management, 2021), pp. 54–68. G.A. Warrier, B. Raphael, Performance evaluation of light shelves, Energy Build. 140 (2017) 19–27. B. Raphael, Active control of daylighting features in buildings, Comput-aided Civ. Inf. 26 (2011) 393–405. Kim Kyungsoo, Lee Heangwoo, Jang Hyangin, Park Changyoung, Choi Changho. Energy-saving performance of light shelves underthe application of userawareness technology and light-dimming control. Sustainable Cities Soc 2019;44:582–96 Additional Declarations The authors declare no competing interests. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6708002","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":459658393,"identity":"abe1ee51-204e-4265-a468-0d2f9888408a","order_by":0,"name":"muhammad sega sufia purnama","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA0ElEQVRIiWNgGAWjYLCChIp/ciD6wAOitTw4c8AYrCWBWB2MD9sOJDaArSNGOX//4sMfEtjupM8PO/wQaIudnG4DAS0SN56lSSTwPMvdeDvNAKgl2djsACFrbpwxY0iQYM7dODsBpOVA4jZCWuRvnP/8IcGAOd1wdvoH4rQYnO9hkEhIOJwgL51DpC2GN9jMJBIOpBlukM4pOJBgQIRf5M4ffvzx5z8befnZ6Zs/fKiwkyPsfYkEqAvBKg0IKQcBfqih8g3EqB4Fo2AUjIIRCQDEa03T/9LpowAAAABJRU5ErkJggg==","orcid":"","institution":"university of indraprasta pgri","correspondingAuthor":true,"prefix":"","firstName":"muhammad","middleName":"sega sufia","lastName":"purnama","suffix":""}],"badges":[],"createdAt":"2025-05-20 12:53:40","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-6708002/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6708002/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":83277689,"identity":"fe5ba9bd-b283-4e93-be9a-d3ecaaadb3f2","added_by":"auto","created_at":"2025-05-22 09:32:28","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":19444,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of Research Method\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6708002/v1/819568ecf49d0a8bbaca9bbd.jpg"},{"id":83277691,"identity":"ed37822a-9b35-4cb9-b47d-7708f4bff3e8","added_by":"auto","created_at":"2025-05-22 09:32:28","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":19038,"visible":true,"origin":"","legend":"\u003cp\u003eRoom models for simulation, facing south, north, east and west orientation\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6708002/v1/e53061c8ed99668883b88c42.jpg"},{"id":83278577,"identity":"46175cfd-daed-4d8d-b06b-750f18df7488","added_by":"auto","created_at":"2025-05-22 09:48:28","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":36914,"visible":true,"origin":"","legend":"\u003cp\u003eRoom model in software Dialux Evo 8.2\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6708002/v1/f152f326f1727788ddd4023f.jpg"},{"id":83277695,"identity":"23427438-def8-49e1-853d-f319ae087756","added_by":"auto","created_at":"2025-05-22 09:32:28","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":32157,"visible":true,"origin":"","legend":"\u003cp\u003e(left) dimension and position of the windows and LS; (right) angle of revolving LS into the room\u003c/p\u003e","description":"","filename":"4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6708002/v1/00122c0932e9ab25800254b4.jpg"},{"id":83277699,"identity":"4c9c7d6d-7096-474c-af89-841f600a9488","added_by":"auto","created_at":"2025-05-22 09:32:28","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":16195,"visible":true,"origin":"","legend":"\u003cp\u003eangle of revolving LS outwards the room\u003c/p\u003e","description":"","filename":"5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6708002/v1/f14b3fb9fdd388ef115abc91.jpg"},{"id":83277692,"identity":"874aef37-1841-4f0e-89b4-68f2801d2094","added_by":"auto","created_at":"2025-05-22 09:32:28","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":38597,"visible":true,"origin":"","legend":"\u003cp\u003esetting sky type, date and time in software Dialux Evo 8.2\u003c/p\u003e","description":"","filename":"6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6708002/v1/646d2d2d0e9e579980e2443a.jpg"},{"id":83279191,"identity":"d59a03e6-d9c9-4274-9760-fd0fcadfde65","added_by":"auto","created_at":"2025-05-22 09:56:33","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":551943,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6708002/v1/f0b68113-3f57-4ea3-b92c-d45c89c8e07d.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003eStudy of Indoor Lighting Uniformity with Revolving Light Shelf\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eNatural lighting is essential in a building [1]. The benefits obtained by users in addition to illuminating activities in the room can also be for health functions [2]. Another advantage is that the source is unlimited. Nowadays, the use of transparent facades allows more light to penetrate the building [3]. But too much light intensity can cause glare [4]. Sunlight also contains heat so the intensity needs to be reduced when entering the room [5].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn tropical climates, the sunlight continues to shine throughout the year with high intensity [6]. This requires buildings to be adapted so that users feel comfortable inside. One of the architectural elements exposed to direct sunlight is the fa\u0026ccedil;ade [7]. Nowadays, with the development of technology, many facades use transparent fields as coverings [8]. Natural lighting becomes easier to enter the space. The adverse effect is that sunlight with high intensity will directly enter and heat the space [9]. This results in a significant amount of energy to cooling the space. On the other hand, covering the facade with a ratio of more massive areas than transparent areas will reduce the intensity of incoming light [10].\u003c/p\u003e\n\u003cp\u003eMany studies have been conducted on the topic of daylighting. In particular, it discusses how to let light into a building without making the entire facade transparent. Light Shelf (LS) is one strategy to let light into a building [11]. By definition, LS is the addition of horizontal slats to the window plane that function to reflect sunlight towards the ceilling so that the reflection is expected to illuminate the floor of the room more deeply [12]. The position of the slats can be horizontal or angled [13]. The placement can be in the room, between and outside the room [14]. configuration of shapes and geometries has been done by many researchers [15]. The addition of solar cells [16], mirrors [17] and even shading [18] has been carried out to improve LS performance. Some performance parameters of LS that are usually used are useful daylight illuminance [19], LU and glare [20].\u003c/p\u003e\n\u003cp\u003eLS can be used in static or dynamic state. Static state, the performance of LS is maximized when certain conditions are met. This led researchers to change LS from static to dynamic state. After the research, it turned out that dynamic LS performed better than static conditions [21]. In relation to energy, dynamic LS requires a power source to move. Although they can be moved manually, it is usually difficult to move them precisely to maximize their performance. While numerous studies have explored light shelf configurations, there is a lack of research on the dynamic adjustment of light shelves in response to changing angles, particularly in tropical climates\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe primary objective of this study is to investigate the effectiveness of a rotation angle of light shelf in enhancing indoor lighting uniformity in tropical climates.\u0026nbsp;\u003c/p\u003e"},{"header":"Methodology","content":"\u003cp\u003eThis research was conducted using a quantitative approach [22]. Measurements of average light intensity and lighting uniformity were carried out by simulating [23] the room model in Dialux Evo 8.2 software. The first step in this research is to determine the area of space to be observed. The model is an experimental room located in Jakarta with 5m length, 5m width and 3m height [24, 25]. Square area is common in recent lighting research to prevent changing in depth of sunlight penetration [26]. Jakarta is selected because it is located in tropic region. Abundant with sunshine all year round but not well utilized [27]. The model is given a window with a size of 4m x 1m with a window height of 1.8m [28]. With a window area of 4 m2 and a wall area of 15 m2, the windows wall ratio of the facade is 26% [29].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe windows wall ratio (WWR) is not 100% because the model is located in the tropics, so the WWR must be adjusted to avoid glare or excessive natural lighting [30, 31]. The model will be made as many as 4 pieces with window orientations facing east, west, north and south. There is only one window per orientation. The next step is to add LS to the window. In this research, the interpane position is chosen for ease of rotation so as not to burden the motor due to heavy loads. 4 models will be given LS with a width of 1m, a length of 4m and a slope of 0\u003csup\u003e0\u003c/sup\u003e. Data collection time is taken at 8am, 10am, 12pm, 2pm, 4pm. Under cloudy sky conditions on September 21, 2024. After data collection, the inclination of the LS was changed to 15\u003csup\u003e0\u003c/sup\u003e towards the inside of the space with the rotating axis in the center, and then the simulation was performed again. Next, simulations were conducted for angles of 30\u003csup\u003e0\u003c/sup\u003e and 45\u003csup\u003e0\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFrom previous research, the function of LS can also be for shading. It protects the interior of the space from glare and direct sunlight. So, in this research, the angle of LS is also rotated out of the building by 15\u003csup\u003e0\u003c/sup\u003e and 30\u003csup\u003e0\u003c/sup\u003e to provide shade.\u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThe simulation results are LU values with numbers between 0 and 1. 0 indicates the absence of uniformity in the room while values closer to 1 indicate a more even lighting distribution. Because of this, it is inevitable that the average illuminance in a room that meets the lighting standards can have a low LU. One reason for this is the presence of direct sunlight which makes the average illuminance high but nonuniform.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eOn the other side, when a room has a low average light intensity, the LU value can be more than 0.5. This is because LU only calculates the lowest light intensity value divided by the average light intensity, so when a room has a low light intensity, the difference between the average and the smallest value is not so significant.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe obtained LU value will determine the angle to be taken as the LS movement. A table will be created based on the orientation so that it can be known, the best angle at that orientation and time. The amount of light intensity in the simulation results can be used as a consideration for choosing the angle of LS motion\u003c/p\u003e\n\u003cp\u003eTable 1 Value of LU in East Orientation\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003eEast\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e8am\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e10am\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e12pm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e2pm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e4pm\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.43\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.38\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.43\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e-30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.53\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eIn the table, we can see that the cells are colored gray. This color indicates the LU value selected as the reference for the LS motion. The consideration for selecting the LU value is not based on the highest value but also on the average indoor lighting intensity. When the LU value is high but the average indoor lighting is low, it is not chosen. Since in this experiment, the use of indoor light is purely using daylight, the office lighting standard of at least 300 lux will be reduced by 30%, which is at least 210 lux. This percentage value is taken because the existing standard requires artificial lighting. In this experiment, no artificial lighting was used.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn the east orientation it can be seen that at 8am, the outward movement of LS by 15\u003csup\u003e0\u003c/sup\u003e is able to create an LU value of 0.49. An LU value of 0.56 is not selected because the average light intensity is below 300 lux. At 10am, the inward movement of 15\u003csup\u003e0\u003c/sup\u003e to 0\u003csup\u003e0\u003c/sup\u003e makes the room have an LU value of 0.38. if the LS does not rotate, the LU value is high but the average light intensity decreases. At 12pm, the LS rotates inward by 45\u003csup\u003e0\u003c/sup\u003e. resulting in an LU value of 0.24. At 2pm, the LS must rotate outward by 15\u003csup\u003e0\u003c/sup\u003e to 30\u003csup\u003e0\u003c/sup\u003e. this rotation results in an LU value of 0.40. At 4pm there is a decrease in performance both rotating inward and outward so the LS does not need to rotate and the LU value becomes 0.43.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 2 \u0026nbsp;Value of LU in West Orientation\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003eWest\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e8am\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e10am\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e12pm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e2pm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e4pm\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.17\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.11\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e-15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.32\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e-30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0.56\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eIn the west orientation, at 8am, the selected LU value was\u0026nbsp;0.40 at the angle of 30\u003csup\u003e0\u003c/sup\u003e. The LU value at the angle of 0\u003csup\u003e0\u003c/sup\u003e was larger at 0.45 but was not selected due to the low intensity result below 100 lux. At 10am, the LS position remained at 30\u003csup\u003e0\u003c/sup\u003e with LU of 0.41. When LS rotates to another angle, there is a decrease in LU value and average light intensity. At 12pm, there was no need for rotation as the LU value was 0.35. The 0\u003csup\u003e0\u003c/sup\u003e angle produced a higher LU value of 0.42 but the average light intensity was low. At 2pm, LS rotated outward by 45\u003csup\u003e0\u003c/sup\u003e and obtained an LU value of 0.53. At 4pm, LS rotated back outward to 15\u003csup\u003e0\u003c/sup\u003e making the LU value 0.56. At 2pm - 4pm, the intensity of direct sunlight is very high resulting in glare. This also results in a low LU value. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 3 Value of LU in North Orientation\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"350\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003eNorth\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e8am\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e10am\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e12pm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003e2pm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e4pm\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.37\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.34\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.28\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e-15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.48\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e-30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 53px;\"\u003e\n \u003cp\u003e0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.62\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eThe north side is different from the east and west sides. This is because the facade is not exposed to direct sunlight. The effect is that the LS on this side reflects more sky light than direct sunlight. The average value of light intensity in the space is also more stable than the other 2 sides. At 8am, the LS rotates 30\u003csup\u003e0\u003c/sup\u003e inward with a LU value of 0.32. At 10am, rotation is not yet necessary because the LU value is still at 0.32 but the average intensity rises by almost 100 lux. At 12pm, the LS had to rotate 15\u003csup\u003e0\u003c/sup\u003e inward to 45\u003csup\u003e0\u003c/sup\u003e to keep the light intensity above 300 lux with a LU value of 0.24. At 2pm, the LS rotated 30\u003csup\u003e0\u003c/sup\u003e inward. The LU value obtained is 0.33. At 4pm, LS rotates outward by 15\u003csup\u003e0\u003c/sup\u003e. this is to get LU of 0.34.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 4 Value of LU in South Orientation\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"348\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 63px;\"\u003e\n \u003cp\u003eSouth\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e8am\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e10am\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e12pm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e2pm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e4pm\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 63px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.36\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 63px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.33\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 63px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 63px;\"\u003e\n \u003cp\u003e45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 63px;\"\u003e\n \u003cp\u003e-15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.44\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 63px;\"\u003e\n \u003cp\u003e-30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 55px;\"\u003e\n \u003cp\u003e0.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 58px;\"\u003e\n \u003cp\u003e0.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e0.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.60\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eThe south side at 8am rotated LS by 30\u003csup\u003e0\u003c/sup\u003e making the LU value 0.32. At 10am, no rotation was performed as the LU value was 0.31. At 12pm, a rotation of 15\u003csup\u003e0\u003c/sup\u003e was performed which did not significantly increase the LU value of 0.26. At 2pm, an inward rotation of 15\u003csup\u003e0\u003c/sup\u003e resulted in an LU value of 0.31. At 4pm, no rotation was required as the LU value was 0.35.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAfter analyzing and selecting the best angle based on the LU value and average light intensity, it can be seen that there is a pattern in each orientation. On the east side, the initial rotation is not inward but outward. This is due to the presence of low-angle direct sunlight. The inward rotation of the LS will result in the sunlight entering more easily because the direction of incoming sunlight is parallel to the slope of the LS. However, if the rotation is outward, then indirectly, the LS functions as a shade and because the angle of incidence of sunlight is low, the rays are able to be reflected into the space further and eventually get a high LU value. in some point. \u0026nbsp;The east side in the afternoon to evening, has a decrease in light intensity due to its farther distance from the sun. This results in less effective LS rotation.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe west side is the opposite of the east side. If in the morning it is the east side that needs shading, then in the evening, it is the west side that needs it. The LS rotating outward is more effective for the dual function of shading and LS.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe north and south sides do not require outward rotation. This is because there is no low angle of sunlight so the outward rotation actually results in low latitude of sunlight. Furthermore, south orientations tend to benefit more from light shelves, as they can effectively diffuse direct sunlight and create a more balanced lighting environment [32, 33]\u0026nbsp;\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFrom recent study, LS can decrease the uniformity of illuminance but this problem can be solved with revolving LS [34, 35]. The finding of this study also confirms that. There is an acknowledged that light shelf with additional technology like dimming control or self-awareness can make performance of LS better [36]. \u0026nbsp;This study can be continued by doing simulations on other dates so that the best angle for LS movement in a year can be obtained. \u0026nbsp;\u0026nbsp;\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eFrom the experiments that have been conducting, it can be seen that the placement of LS in each orientation with a given rotation will produce different LU values every hour. The best LU value is obtained on the east side with an outward rotation of 15\u003csup\u003e0\u003c/sup\u003e then a maximum inward rotation of 45\u003csup\u003e0\u003c/sup\u003e. For the west side, the rotation starts from the inside out. The best LU value is obtained when the LS rotates 30\u003csup\u003e0\u003c/sup\u003e inward and then outward by 30\u003csup\u003e0\u003c/sup\u003e. The north side gets the best LU value when the LS can rotate in the range of 15\u003csup\u003e0\u003c/sup\u003e to 45\u003csup\u003e0\u003c/sup\u003e inward. The south side gets the LU value according to the standard by rotating in the range of 30\u003csup\u003e0\u003c/sup\u003e to 45\u003csup\u003e0\u003c/sup\u003e. Considering the efficiency of LS movement, the south side has the least movement, only moving from 30\u003csup\u003e0\u003c/sup\u003e to 45\u003csup\u003e0\u003c/sup\u003e. The most movement is on the west side LS.\u003c/p\u003e "},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eCompeting Interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author(s) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eS. Krasić, P. Pejić, P. Mitković, Significance of daylight in the design and construction of buildings. Gradjevinar. 65, 833\u0026ndash;840 (2013).\u003c/li\u003e\n\u003cli\u003eM. N. Mead, Benefits of sunlight: a bright spot for human health. 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Sustainable Cities Soc 2019;44:582\u0026ndash;96\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"lighting uniformity, revolve, daylight, light shelf ","lastPublishedDoi":"10.21203/rs.3.rs-6708002/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6708002/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eLight shelf is one of the devices to help the penetration of light into the building. Research discussing the light shelf starting from the shape, position and variations have been conducted to maximize its performance. Most of these variations are in a static state even though the sun has movement throughout the day. While numerous studies have explored light shelf configurations, there is a lack of research on the dynamic adjustment of light shelves in response to changing angles, particularly in tropical climates The primary objective of this study is to investigate the effectiveness of a revolving light shelf in enhancing indoor lighting uniformity in tropical climates. The method used in this research is computer simulation with Dialux Evo 8.2 software. The results indicated that after analyzing and selecting the best angle based on the Lighing Uniformity value and average light intensity, it can be seen that there is a pattern in each orientation. Judging from the efficiency of light shelf movement, the south side has the least movement, which only moves from 30\u003csup\u003e0\u003c/sup\u003e to 45\u003csup\u003e0\u003c/sup\u003e. The most movement is on the west side light shelf..\u003c/p\u003e","manuscriptTitle":"Study of Indoor Lighting Uniformity with Revolving Light Shelf","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-22 09:32:23","doi":"10.21203/rs.3.rs-6708002/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"871a0adc-aa8e-4301-ae75-c4cd5f8d9fb7","owner":[],"postedDate":"May 22nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":48828474,"name":"Architecture, Design and Planning"}],"tags":[],"updatedAt":"2025-05-22T09:32:23+00:00","versionOfRecord":[],"versionCreatedAt":"2025-05-22 09:32:23","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6708002","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6708002","identity":"rs-6708002","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}