Lighting design

1. There are norms that impose illuminances level, the UGR and Ra, to be achieved according the local and the type of activity. These norms considers that the design of artificial lighting is done for the night condition (no natural lighting). But during the day, it is important to take into account the natural lighting. The principle is to use a maximum of the free lighting and to complete it with the artificial lighting. There is different way to control the artificial lighting to use it only when it is required/needed. Schedule management (timer) Presence and absence detector The dimming of the lamp depending of the available natural light. All the parameters of a lighting project Lamps, Luminaries Projection mode (direct, indirect, direct/indirect, at 2components) … have to be choose according to the activity and type of rooms: Office, Residential, Hospitals, School, Sport hall, Industrial halls. Lighting design Source : M Bodart, J. Chabaudie, A. Liébard, A. De Herde, Guide de l'architecture bioclimatique, cours fondamental : Tome 5. Construire avec l'éclairage naturel et artificiel, Système solaires : l'observateur des énergies renouvelables, Paris, 2003 Source :Architecture et Climat

2. Lighting design Projection mode . direct projection send the light directly from the source to the work plane. + the efficiency of the system : most part of the light are not reflect before to attempt the surface/task to light - high risk of glare and irregularity of light repartition (not close to the natural light) indirect projection use a surface as a reflector to diffuse the light, mostly the ceiling and sometimes walls. + - it is a good solution to be protect of the glare - uniform repartition of light - -the quantity of reflect light depends strongly on the reflection coefficient of walls use for the indirect projection - no shadow effect = monotonous - efficiency depends of the property of luminaries (dust,…) and walls direct/indirect is similar to the indirect projection with the benefit of the direct projection to light the working plane. at 2 components consists of use the direct or indirect projection for the general lighting of the local and to use a fill light to boost it when it is needed. Source : M Bodart, J. Chabaudie, A. Liébard, A. De Herde, Guide de l'architecture bioclimatique, cours fondamental : Tome 5. Construire avec l'éclairage naturel et artificiel, Système solaires : l'observateur des énergies renouvelables, Paris, 2003 Source :Architecture et Climat

3. Lighting design 2. Luminous flux control 2.1. The dimming of the lamp depending of the available natural light. Flux variation : depending of the availablenatural light. Depending of the sensor objectif : switch on/off decrease or increasestep by step : -Dimming rows of lights from the windows, -Variation on the number of lighted lamps in luminairesmultilamp Continuousdimming of the intensity Parameters Availablenaturallighting objectives ( ex: lux on the working plane) Groupment : the control canbedone by : local luminaries regroupement : the clustering is important to optimize the control use and depends of the design/planning of the local. The drawing show twolighting circuit, the left corresponds to a zoning related to the presence of natural light, the right don’t take into account this free energy input. decrease or increasestep by step Continuousdimming of the intensity Source : M Bodart, J. Chabaudie, A. Liébard, A. De Herde, Guide de l'architecture bioclimatique, cours fondamental : Tome 5. Construire avec l'éclairage naturel et artificiel, Système solaires : l'observateur des énergies renouvelables, Paris, 2003

4. Lighting design 2.2. Schedule management (timer) In building with fix work schedule (office building) an automatic schedule management of the switch on/off by zone or for the complete building is useful because the more users less they fell responsible. A timer ensures a switch off in the local where the presence is momentary/ponctual. For example : in the circulation area, hallway of residential building a timer is a good solution to control the switch off after the passage of the occupants 2.3. Presence and absence detector/sensor When the presence is not scheduled but occasional (sanitary, meeting room,…) a presence or absence detector is the adequate control system. Presence detector switches lights when entering. Absence detector implies the use of the switch when entering in the local but it control the switch off when absence are detected. There exists two technologies for this device : Passive Infrared Detectors - PIR (Passive InfraRed) sensors High frequency - HF (High Frequency).sensors PIR type sensors detect the motion of a hot body while HF technology uses the Doppler effect (reflection of the different waves on a body in motion) in the manner of a radar Sources : B. Roisin, A. Deneyer, M. Bodart, P.D’Herdt, B. Deroisy, Guide pratique et technique à l’éclairage des logements, Architecture et Climat, UCL, Division Energie et Climat, CSTC, availablesoon

5. Lighting design Source :Architecture et Climat

6. Lighting design • Comfortcharacteristic • Uniformity • The uniformityindicates the repartition of the ligth in a local and isgiven by the following formula : • U= Imin/Imean • In the norm EN 12464-1, the uniformity have to be • >= 0.7 on the working plane • >= 0.5 for the rest of the local. Source :Architecture et Climat

7. Lighting design Direct glare • UGR ( = United Glare Rating) Glare = viewing conditions in which the individual is less able to perceive objects, as a result of excessive luminances and contrast in space and time. • The UGR is the indication of direct glare in a space lit artificially. • UGR ↗ = glare↗ • With, • Lb : background luminanceL : luminance of the luminous part in the direction consideredw: solid angle of light at each part of the eyep: index of Guth position  UGR for a given position • Can becomputedfrom a table or by a software. • For the norm EN 12464-1, the UGR have to bebetween 16 ≤ UGR ≤ 28 Indirect glare

8. Lighting design Tools and application To assess the size of a project in artificial lighting, there are different simulation tools. Dialux For example Dialux , assesses levels of illumination obtained with a specific lighting installation and a well defined architectural configuration. Dialux : First create a local and its environment (color of the walls, furniture, clean room). Then, allows the user to choose the lighting device to be tested according to their power, their efficiency and photometric curve. Once selected, they must be positioned in the room. Finally, DIALux assesses levels of illuminance over an area/working plane defined by the user. Source :Architecture et Climat

9. Lighting design DAYSIM DAYSIM software allows to calculate the energy expenditure for lighting in a dynamic simulation that evaluate the availability of daylight. “Level of annual illuminances are associated with the occupation patterns/profile of the user to predict the annual use of electric lighting depending on the control strategy of lighting and shades.” Occupation profile is determined by an other software “Lightswitch” and validated by some field study. Daysim : First you have to defined the room in a drawing tool (SketchUp, Ecotect,…) Second you have to load the climate file and your building file Third you have to fixe, the parameters for the daylight simulation. After calculation, you have to fixe the users behavior, lighting installation, the shading device,… Then daysim give you, electrical consumption, internals gain, illuminances levels, daylight factor, … Source :Architecture et Climat

10. Lighting design A studentproject : “Lighting design project for an installation in a local office” Students have to size a lightingproject, for a local. They have to use the Dialux software to analyze the differentsparameters : -Illuminances, -UGR, -Uniformity, -efficiency, -… They have to respect the levelsimposed by the norm and reach a good efficiency.