QUALITY ANALYSIS OF ROOM NATURAL LIGHTING USING SPATIAL INTERPOLATION WITH KRIGING METHOD

The results of this study, where natural lighting can affect the lighting in the room, with the entry of natural lighting into the room through 4 open windows. The data retrieval process is for 1 day through special interpolation measurements using the Kirging method. The stages of data collection are in the morning, afternoon and evening with 3 windows open and 4 windows open. The intensity of light when 3 windows are open is a minimum average of -50 lux – 1350 lux in the morning and a maximum of -50 lux -1450 lux during the day, while the condition of 4 open windows is that the minimum average lighting is 0 – 1700 lux in the morning and maximum 50 lux -1750 lux during the day d. natural lighting can make reference to the lighting schedule in the room where the condition of 4 open windows is a mix of 5 points in the afternoon and a minimum of 3 points during the day. The electric power obtained is a maximum of 36 kWh, a minimum of 21.5 kWh and the resulting cost is a maximum of RP. 51,597, a minimum of RP. 30,814.87 so that the average energy efficiency of electric power reaches 11. 75%, the highest and the lowest reaches 11. 58% and efficiency towards costs reaches 58%.


Introduction
The sun is a natural light source from nature with very high light intensity (Sanders, Frago, Kehoe, Patterson, & Gaston, 2021). This natural lighting is very well used and utilized by humans lack of natural lighting that enters the room (Mahmoud, 2021), so the use of artificial lighting is more effective (Setiati & Budiarto, 2021). The study in this research is the relationship of natural lighting to the learning room (González-Zamar, Jiménez, & Ayala, 2021), where the factor causing the low natural light produced is because the sky is covered (covered) by clouds so that the sun's rays do not penetrate directly to the earth not maximally (Nicastro et al., 2021). Natural lighting is needed to support indoor activities both in industry and in high-rise buildings, office buildings, campuses and apartments in the special city in the capital Jakarta (Noviani & Jesica, 2021). The benefits of natural lighting to help lighting in the room more effectively can reduce lighting sourced from lower electrical energy by 25-35% (Ndaaru, 2021). To identify the indoor light intensity more accurately (Feng et al., 2021), the researchers conducted a simulation of the indoor lighting intensity measurement (instrument) using the kriging technique-based spatial interpolation method (Lee, Irwin, Irwin, & Miller, 2021). The measurement process was carried out for 1 day starting at 08.00 WIB -16.00 WIB. The results of the measurement of lighting in the room are quite uniform which does not produce contrasting lighting (de Vries, Heynderickx, Souman, & de Kort, 2021) which can be seen in the lighting map image below. The level of utilization of natural lighting makes the conservation of electrical energy in the room the environment (Boulanger et al., 2021). It is necessary to know that the glass wall in the building is very influential on the lighting in the room (Wu, Zhou, & Li, 2021) where natural light directly penetrates into the room (Li, Wu, Yuan, & Zuo, 2021) so that it can reduce lighting sourced from lighting, this is one of the savings in the use of electricity in the learning room (Avgoustaki & Xydis, 2021). The determination of the lux of indoor lighting follows the Indonesian National Standard where the standard of the room designer by producing lux brown light which is recommended by the Indonesian National is a used room of 250 Lux, office space of 350 Lux, Laboratory room of 500 Lux, Study room of 300 Lux and a hall or multipurpose building 250 Lux. The place where the researcher carried out the instrument in the design of the existing class room had 4 windows with dimensions of 3 meters x 1.8 meters, where the window was made of glass material, one of which helped the distribution of light from outside into the classroom. The location of the window is on the back and right side of the class, the classroom has 4 windows where the opening of the window researchers can take measurements and collect sample data to analyze lighting in the IT-PLN classroom using Kriging-based technology, one of the techniques of the geo-technical method. statistical is used to spatially analyze the intensity of lighting in the indoor room area. Of course, there are steps that are taken during the measurement, where before the light shelf is exposed to natural lighting, the threshold for overlapping the shape of the walecontet, before the ideal period can form three different light shelf forms, detecting the opposite energy use of the light shelf. Indoor lighting can create perspectives in different study rooms, and lighting is a fundamental that can support the learning process, indoor teaching and other activities.

Lighting Criteria
Natural lighting, namely lighting obtained from the sun, lighting can reduce the consumption of lighting in the room. Natural lighting can also be in the form of electromagnetic waves with a frequency of 380-780 manometers. The natural lighting factor is a form of irradiation of light from the sun directly to the earth. There are three elements can be seen in the image below.
Picture 1. Reflection Component Shape. Volume 3, No. 3, January 2022, pp. 223-237 225 http://devotion.greenvest.co.id Based on Picture 1 above is the form of light rays from the sun that radiate into the room where the sky component (sky-fl) is external lighting obtained directly from sunlight with an infinite electrical peak, the external shadow component (FRL) is lighting with reflected rays and produces shadows or substances residing into the room, the inner shadow component (frd) is lighting that illuminates from the outside directly into the room and produces shadows with substances on the outer glass layer. The internal natural lighting factor is determined by the alignment of the window opening.

Lighting
The intended lighting is from a lamp energy source where the intensity of lighting in an indoor area is expressed as a flux with a reservoir area of m². The refractive intensity of the light rays from the lamp is determined in general where the vertical side is 80 cm above the floor. In the colored plane and in the horizontal area, the intensity of lighting E is expressed as lux or lumen/m², while the flux is placed with an area of A m. To find out, see the lumen equation below.
………………………………………..……………… (2) Where : C = Exposure factor En = lumen Lighting from sunlight that enters the room experiences reflection where the rays come, the rays reflect on the normal line which is one of the flat planes can be seen in the image below.
Picture 2. Relationship of Lines and Lighting.
Picture 2 above explains the relationship between the vertical normal lines located in a flat plane, the source is the shape of the incident ray, namely (i), the Angle of Incidece and the reflected ray is stated (r), the Angle of Reflection and for the law of Reflection i = r, as for the glare index. on the light/lighting can be seen in the table below.

Spatial Interpolation
Prediction of natural lighting during the day is done by spatial analysis. Kriging is a geo-statistical method with a technique used to interpolate units of random field values at a location. The lack of discrete observer values at the nearest location, with a geostatistical approach, describes the spatial pattern and interpolates the main variables at locations that have not been sampled. geo-statistical and used to model the uncertainty of the error in the forecast area can be seen in the general interpolation equation expressed as follows: …………………………………

Measurement Scheme
The measurement scheme is carried out in the teaching and learning room 1004 at the Institute of Technology-PLN Jakarta where the light measurement uses a lux meter (Smart sensor brand), the measurement accuracy is approximately 5% with a range of 0 -200,000 lux starting from 08.00 -16.00 WIB. There are three stages of the measurement process, namely morning, afternoon and evening and the measurement results can be seen in each table below.    Table 4 above describes the conditions during the day when the window is open, the total lux at 60 observation points is the lowest average total lux is 1481.56. The lowest value of Lux room is 24.69 with a window area of 5.40m², the highest value is in the 4th condition, namely Total lux is 22153.00 and the Average Lux room is 369.22 with a window area of 21.60m² lux that enters is 68.37. The graph for measuring the condition of the open window in the morning, afternoon and evening. with the window area and the average lux in the room so that it can be seen more clearly in the graph below.

229
http://devotion.greenvest.co.id  Picture 6 above explains the highest lux value of 360 in the 4th condition, the lowest lux value of 025 in the 1st condition.

Lighting Modeling
From the mapping of indoor lighting carried out in every condition with existing lamps installed, namely the 36 watt TL-D lamp type in the learning room, where the natural lighting produced is not evenly distributed so it needs additional lighting from electrical energy. light is turned on. There are several images that are displayed as a result of mapping the lighting conditions in the morning, afternoon and evening as follows:      The cost of kWh when window 4 is open, namely the daytime condition is 21.5 kWh and the cost is RP.30,814.8 and the highest value for the afternoon condition is 36 kWh and the cost is RP.51,597.

Efficiency
The intended efficiency is saving on the use of lamps which affect the cost of kWh of electricity in the room, because the lighting in the room has been assisted by natural lighting, namely sunlight.

Conclusion
Lighting is a major need in indoor environments such as homes, offices, hotels, campuses and other commercial buildings. Data were collected by measuring (instrument) the lighting in the room, by spatial interpolation using the shower kriging program method. The steps for measuring the condition of the window are closed, window 3 is open and window 4 is open, namely in the morning, afternoon and evening. The results of the measurement (instrument) that window 3 is open in the morning, large lux minimum -50 -250 lux, maximum 650 -1350 lux, minimum daytime -50 -250 lux, maximum 650 -1450 lux and minimum afternoon -50 -250 lux, maximum 650 -1450 lux. Then window 4 opens in the morning with a minimum lux of 0 -200 lux, a maximum of 700 -1700 lux, a minimum of 50 -250 lux during the day, a maximum of 650 -1750 lux and a minimum of 50 -250 lux in the afternoon, a maximum of 650 -1750 lux. the number of light points that are turned on in the condition of the open windows 3 in the morning 10 points, 4 points during the day and 5 points in the afternoon. window conditions 4 open in the morning 4 points, 3 points in the afternoon and 5 points in the afternoon. The average power consumption in 1 month is a maximum of 36 kWh, a minimum of 21.5 kWh. The resulting fee is a maximum of Rp. 51,597 and a minimum of Rp. 30,814.87 so that the energy efficiency of electric power reached 11.75 % the highest and the lowest reached 11. 58%.