## 10.5 Case study 4: High lighting quality targets with minimum electric power density

Place : France (Lyon)

Building type: Office

Contact : Marc Fontoynont (Ecole Nationale des Travaux Publics de l'Etat)

### Introduction

A campaign has been conducted so as to test efficient lighting installations during six months in the area of Lyon, France. 26 work places were tested, each of them with a specific lighting scheme. The goal was to identify directions in preferred lighting schemes requiring less electrical power. Users could adjust their lighting conditions using different control systems: dimmer, daylight and occupancy sensors, ambient/task luminaires. The preferred lighting schemes were carefully recorded through measurements of illuminance distribution, luminance values in the field of view, electric power required by the lighting installation for the selected lighting scheme.

Selected electric power densities and lighting quality parameters were compared. No correlation was found between perceived lighting quality parameters and electric power densities, but some solutions were found, with the best assessment in quality and power densities below 10W/m².

<figure><img src="image_200.png" /><figcaption>Figure 10-21. One of the luminaires in the case study.</figcaption></figure>
<figure><img src="image_201.png" /><figcaption>**Figure 10-22.** Example of computer generated images of various lighting schemes for cubicles tested to identify preferences among observers.</figcaption></figure>

## Conditions of the experimentation

The spaces belong to an existing office building in Lyon, France (Mat Electrique). Ceiling height was 2.64 m, window frame are 1.25 m in width. Each work station offers a specific floor area 15-27 m² in individual, 9-13 m² if shared and 9 m² in open space. Surface of desks were around 1.6 m x 0.8 m, and each work station offered storage furniture.

<figure><img src="image_202.png" /><figcaption>**Figure 10-23.** Office building, Lyon, France. Third floor offered open and individual spaces for the tests.</figcaption></figure>

## Organization of the campaign

Various lighting installations were tested during a period of four months in real work places in the building. The test involves twenty-six workplaces, most of them being in an open space area and some of them in individual or shared offices. All the workplaces are equipped with a computer and a visual display terminal.

First of all, diagnosis was made for each workplace by interviews and measurements (natural and artificial lighting: illuminances, luminances, shadows, blinds, control habits, optical characteristics of the worker).

Then, 26 lighting schemes were proposed, distributed in the following families: recessed ceiling luminaries, direct / indirect suspended, stand alone, desk mounted. Most of them were equipped with a dimming system (so that the occupants could adjust freely the power to the system) or automatic sensors (occupancy + daylight), or separated ambient/task switch.

Occupants were interviewed at various occasions and were asked to evaluate the quality of their luminous environment with respect to the light distribution in their work area, the visual comfort (evaluation of glare), the light distribution on surrounding surfaces (walls, ceiling).

Luminances were measured from the typical location of the eye and illuminance was measured on the surfaces. The electric power consumption of lighting was measured. The aim was to identify two major
general parameters:

- the electric power density used by the occupant (W/m² over the entire work area)

- general perceived lighting quality index

To calculate the general perceived lighting quality index, comments of the occupants were reviewed and analysed in order to include them in a general single scale of satisfaction.

The proposed rating obtained through interviews: soft, satisfactory (4 points), lack of uniformity, lack of brightness, poor aesthetics (3 points), unpleasant, sad (2 points), glary, aggressive, tiring (1 point).

Lighting quality was measured through the parameters: dimming capability, illuminance levels, uniformity on work plane, value of UGR, maximum perceptible luminance (overhead glare), and maximum luminance of scene without luminance of luminaire.

## Results

There was a clear rejection for any directly visible fluorescent lamp (T5 or T8, CFL). It is found however that when fluorescent lamps were partly dimmed, the luminance of the lamps was acceptable. It seems that the threshold value is 7 000 cd/m²: fluorescent lamps above head with luminances below 7 000 cd/m² seem to be acceptable. There was also a clear preference for systems hiding totally the visibility of the fluorescent lamps, and indirect lighting systems.

There was a clear preference for powerful task lighting contributing also to the ambient light, which is able to supply up to 500 lx on the desk, with a good uniformity (0.6 to 0.8). The uniformity on the desk is the ratio of the minimum illuminance (230 to 350 lx) to the average illuminance (around 400 lx).

There was a great satisfaction in having dimming systems with individual controls. Although occupants did not use them often, they offer a guaranty that they could adjust the illuminance level according to their needs and physical state (fatigue, stress, etc.).

There was a large variation in the energy efficiency of the lighting solutions. The lowest power densities were obtained with suspended direct-indirect luminaries shared by two occupants (6 W/m²). Low power densities were also found for task/ambient lighting solutions (below 8 W/m²).

Individual task lamps could be designed with a power of 25-40 W, able to provide good illuminance uniformity on the work plane. In these conditions, power densities of about 6 W/m² are achievable, with good visual conditions.
<figure><img src="image_203.png" /><figcaption>**Figure 10-24.** Perceived visual quality as a function of the electric power density for lighting for 26 lighting schemes.</figcaption></figure>

## Most efficient schemes

<figure><img src="image_204.png" /><figcaption>**Figure 10-25.** Direct-indirect stand alone luminaire.</figcaption></figure>

### Characteristics of direct-indirect stand alone luminaire:

- Independence with the ceiling allows locating the luminaire very precisely near the work space

- The users appreciated the dimming option associated to the daylighting-occupancy sensor

- It can be shared with another occupant

- Typically 100W per work space required, less than 8W/m² in open plan office

- Typical light sources 2 x CFL 55W per occupant, partly dimmed
<figure><img src="image_205.png" /><figcaption>**Figure 10-26.** *Direct-indirect suspended luminaire.*</figcaption></figure>

<figure><img src="image_206.png" /></figure>

Characteristics of direct-indirect suspended luminaire:

- Allow usage of 1.20 or 1.50 m fluorescent tube but work place cannot move if luminaire position is fixed

- Leads to the lowest power density: 6 W/m² in open plan office

- Could use 2x54 W fluorescent lamps for two people

<figure><img src="image_207.png" /><figcaption>**Figure 10-27.** *Indirect luminaire integrated in the furniture.*</figcaption></figure>

<figure><img src="image_208.png" /></figure>

Characteristics of indirect luminaire integrated in the furniture:

- Judged as very comfortable

- The ceiling luminances are moderate

- The general feeling tends to have a work plane looking darker than the rest of the room

- Requires on average of 2x35 W fluorescent lamps per work place

## Conclusions

In summary, the possible specifications of lighting installations in offices perceived as high quality are:

- Hide light sources so that the maximum luminance of the luminaire in all directions is below 7000 cd/m²
- Reduce uniformity on work plane to a value between 0.6 and 0.8 to provide a feeling of contrast while avoiding shadows

- Allow individual control (dimming)

- Select equipment with good optical performance

- Prefer single fluorescent lamp to CFL to lower power density

- Share luminaries between work places: best performance are obtained with one luminaire providing light for two workplaces
## 10.6 Case Study 5: Renovation of a cultural centre

Place: Sweden (Stockholm)

Building type: Service sector, library

Contact: Lars Bylund (Bergen School of Architecture)

<figure><img src="image_209.png" /><figcaption>Figure 10-28. Outside Photography</figcaption></figure>

Technology: LED Philips K2 of 3 W in luminaries DeltaLux

Reading places:

Replacement of compact fluorescent lamps (18 W) by 4 LED of 3 W each

Benefits of Illuminance on the work plane: +40%

Shelves for books consultation:

Replacement of fluorescent lamps (28 W) by 6 LED of 3 W each

Benefits of Illuminance, down the racks: +100%

Hall of the stairs

Replacement of each low-voltage lamps (20 W) by a LED of 3 W

All the descriptive and the informative posters are lit with the LED technology.

<figure><img src="image_210.png" /><figcaption>Figure 10-29. Pictures of the installation</figcaption></figure>
## 10.7 Case study 6: Sture Library in Stockholm fully lit by LED lighting

Place: Sweden, Stockholm

Building type: library

Contact: Lars Bylund

The lighting in library was fully realised with LED lighting. Total power was 1134 W with LEDs.

- lighting power density 5.5 W/m²

- luminaries: Fortimo 45 W Dim 830 and REBEL 3 W

- CCT= 4000 K

- vertical illuminance on the book shelves 250 to 500 lx

- horizontal illuminance between 200 to 700 lx

<figure><img src="image_211.png" /><figcaption>**Figure 10-30.** Vertical illuminances are between 250 and 500 lx.</figcaption></figure>

<figure><img src="image_212.png" /><figcaption>**Figure 10-31.** Lighting with Fortimo luminaire.</figcaption></figure>

<figure><img src="image_213.png" /><figcaption>**Figure 10-32.** The linear luminaire realised with 10 x 3 W Rebel LEDs.</figcaption></figure>
## 10.8 Case study 7: Town hall in Stockholm

Place: Sweden, Stockholm

Building type: administrative

Contact: Lars Bylund

<figure><img src="image_214.png" /><figcaption>Figure 10-33. Town hall of Stockholm.</figcaption></figure>

<figure><img src="image_215.png" /><figcaption>Figure 10-34. 26 W CFL replaced with 18 W Fortimo LED.</figcaption></figure>

<figure><img src="image_216.png" /><figcaption>Figure 10-35. 20 W tungsten halogen lamps above the doors replaced by 2 x 3 W Rebel LEDs.</figcaption></figure>

<figure><img src="image_217.png" /><figcaption>Figure 10-36. 2 x 35 W tungsten halogen lamps replaced by 2 x 3 W Rebel LEDs giving light up and down.</figcaption></figure>
## 10.9 Case study 8: Turning Torso

Place: Malmö, Stockholm

Building type: residential

Contact: Lars Bylund

<figure><img src="image_218.png" /><figcaption>**Figure 10-37.** *Turning Torso, an apartment building in Malmö, Sweden.*</figcaption></figure>

Turning Torso is a 54-storey-high apartment building. All the corridors connecting the apartments are without windows. The lighting in the corridors is completely based on LEDs. By choosing LEDs as the light source, the power was reduced from the initially planned fluorescent lamp lighting at 43 W/m of corridor length to 10 W/m. This gives 75% reduction in total installed power. Additionally, the maintenance costs were reduced as a result of the longer lifetime of LEDs, which are guaranteed for 50000 hours.

The average illumination level in the corridors is 170 lx, slightly higher than the planned 150 lx for the fluorescent lighting. The installation was completed in 2004 and consisted of 18 240 LEDs (1,2 W each) from Osram with a correlated colour temperature of 5400 K.
## 10.10 Case study 9: Comparison of LED and fluorescent lighting in a meeting room

Place: Finland (Espoo)

Building type: Office building

Contact: J. Viitanen (Aalto University School of Science and technology)

### Place description

<figure><img src="image_219.png" /><figcaption>Figure 10-38 Meeting room 271</figcaption></figure>

Meeting room 271 is located in Otakaari 7 and is part of Aalto University's Lighting unit. Size of the meeting room is 7 m x 4,7 m x 2,7 m.

Room contains 6 fluorescent luminaires and 2 LED luminaires. Both of these are recessed ceiling luminaires. It is also possible to utilize daylight in the room, but for this case study daylight capabilities were removed.

### Luminaires:

<figure><img src="image_220.png" /><figcaption>Figure 10-39 Greenlux GLP 6060-30</figcaption></figure>

<figure><img src="image_221.png" /><figcaption>Figure 10-40 Philips Indolight TBS300</figcaption></figure>

<table><caption>Table 10-3. Luminaire installation specifications</caption><thead><tr><th>Luminaire</th><th>Philips Indolight TBS300</th><th>Greenlux GLP 6060-30 (max)</th><th>Greenlux GLP 6060-30 (dim preset 4)</th></tr></thead><tbody><tr><td>Number luminaires in the room</td><td>6</td><td>2</td><td>2</td></tr><tr><td>Source of light</td><td>2 x 28W TL5</td><td>336 x 0.2 W LED</td><td>336 x 0.2 W LED</td></tr><tr><td>Dimming [%] (0=full power)</td><td>0</td><td>0</td><td>55.5</td></tr><tr><td>Electrical power of luminaire [W]</td><td>64</td><td>62.3</td><td>27.7</td></tr><tr><td>Total electrical power of luminaires [W]</td><td>384</td><td>124.6</td><td>55.4</td></tr><tr><td>Color temperature [K]</td><td>3000</td><td>3000</td><td>3000</td></tr><tr><td>Luminous flux [lm]</td><td>5200</td><td>3460</td><td>1700</td></tr><tr><td>Color rendering index Ra</td><td>80</td><td>56</td><td>56</td></tr><tr><td>Luminous efficacy of luminaire [lm/W]</td><td>81.25</td><td>55.5</td><td>61.4</td></tr></tbody></table>
<table><tr><td>Electrical power density [W/m2]</td><td>11.43</td><td>3.71</td><td>1.65</td></tr><tr><td>Average luminous power in the working area [W/100 lx]</td><td>50.68</td><td>43.48</td><td>38.08</td></tr></table>

The most notable thing about the luminaire specifications is that LED luminaire's luminous efficacy increased with dimming. Fluorescent luminaire had better luminous efficacy than LEDs.

## Measurements

Illuminance, luminance and UGR values of the lighting installations were measured.

Philips Indolight FL luminaires were measured using only full power but Greenlux LED luminaires were measured in addition using preset dimming level (dim = 55.5%).

fluorescent and LED measurements cases were different, because fluorescent luminaires covered the whole meeting room but LEDs only the working area. Therefore the results are not fully comparable.

<table><caption>Table 10-4. Measured illuminance levels</caption><thead><tr><th></th><th>Em [lx]</th><th>Emin [lx]</th><th>Emax [lx]</th><th>Emin/Em</th><th>Emin/Emax</th></tr></thead><tbody><tr><td colspan="6"><strong>WORKING SPACE</strong></td></tr><tr><td>Philips Indolight</td><td>849</td><td>740</td><td>972</td><td>0.87</td><td>0.76</td></tr><tr><td>Greenlux LED (max)</td><td>314</td><td>205</td><td>398</td><td>0.65</td><td>0.52</td></tr><tr><td>Greenlux LED (dim = 55%)</td><td>159</td><td>105</td><td>201</td><td>0.66</td><td>0.52</td></tr><tr><td>RECOMMENDATION (SFS-EN 12464-1)</td><td>500</td><td></td><td></td><td>&gt;0.7</td><td></td></tr><tr><td colspan="6"><strong>ADJACENT AREA</strong></td></tr><tr><td>Philips Indolight</td><td>542</td><td>277</td><td>714</td><td>0.51</td><td>0.39</td></tr><tr><td>Greenlux LED (max)</td><td>147</td><td>87</td><td>220</td><td>0.59</td><td>0.40</td></tr><tr><td>Greenlux LED (dim = 55%)</td><td>80</td><td>47</td><td>113</td><td>0.58</td><td>0.42</td></tr><tr><td>RECOMMENDATION (SFS-EN 12464-1)</td><td>300</td><td></td><td></td><td>&gt;0.5</td><td></td></tr><tr><td colspan="6"><strong>WHOLE AREA</strong></td></tr><tr><td>Philips Indolight</td><td>649</td><td>277</td><td>972</td><td>0.43</td><td>0.28</td></tr><tr><td>Greenlux LED (max)</td><td>205</td><td>87</td><td>398</td><td>0.42</td><td>0.22</td></tr><tr><td>Greenlux LED (dim = 55%)</td><td>108</td><td>47</td><td>201</td><td>0.44</td><td>0.23</td></tr></tbody></table>

Fluorescent luminaires gave much more light than LEDs but this is mainly because of the larger amount of luminaires used in the fluorescent installation. LED luminaires used less W/100 lx as can be seen in Table 10-3.
<figure><img src="image_222.png" /><figcaption>Figure 10-41. Luminance distributions of the measured room</figcaption></figure>

<table><caption>Table10-5. Measured luminance levels</caption><thead><tr><th></th><th>Philips<br>Indolight<br>TBS300</th><th>Greenlux<br>(max)</th><th>Greenlux<br>LED (dim =<br>55%)</th></tr></thead><tbody><tr><td><strong>Surface luminances of the luminaires</strong></td><td></td><td></td><td></td></tr><tr><td>average [cd/m2]</td><td>9152</td><td>3988</td><td>1709</td></tr><tr><td>max [cd/m2]</td><td>15400</td><td>5170</td><td>2230</td></tr><tr><td>min [cd/m2]</td><td>998</td><td>2782</td><td>1269</td></tr><tr><td><strong>Luminances of the installation<br>from the door</strong></td><td></td><td></td><td></td></tr><tr><td>average [cd/m2]</td><td>146</td><td>35</td><td>18</td></tr><tr><td>max [cd/m2]</td><td>26309</td><td>5270</td><td>2728</td></tr><tr><td>min [cd/m2]</td><td>1.7</td><td>1.5</td><td>1.5</td></tr><tr><td>UGR (recommendation = 19)</td><td>15.8</td><td>19.5</td><td>16.7</td></tr><tr><td><strong>from the end of the table</strong></td><td></td><td></td><td></td></tr><tr><td>average [cd/m2]</td><td>149</td><td>57</td><td>31</td></tr><tr><td>max [cd/m2]</td><td>29249</td><td>4936</td><td>2840</td></tr><tr><td>min [cd/m2]</td><td>1.6</td><td>1.5</td><td>1.5</td></tr><tr><td>UGR (recommendation = 19)</td><td>19.6</td><td>18.1</td><td>15.1</td></tr><tr><td><strong>Ceiling luminance (above the working<br>area)</strong></td><td></td><td></td><td></td></tr><tr><td>average [cd/m2]</td><td>49</td><td>20.1</td><td>10.1</td></tr><tr><td>max [cd/m2]</td><td>55</td><td>32.1</td><td>16.2</td></tr><tr><td>min [cd/m2]</td><td>25.7</td><td>10.9</td><td>5.6</td></tr><tr><td><strong>Surface luminance of the table</strong></td><td></td><td></td><td></td></tr><tr><td>average [cd/m2]</td><td>100.8</td><td>40.6</td><td>23.8</td></tr><tr><td>max [cd/m2]</td><td>115.9</td><td>48.3</td><td>28.4</td></tr><tr><td>min [cd/m2]</td><td>90.4</td><td>30.1</td><td>17.7</td></tr></tbody></table>

Luminance levels of the meeting room were lower with LED lighting than with fluorescent lighting. This was mainly due to smaller amount of LED luminaires and also much less power was used for the
LED lighting. Electrical power density was 11.43 W/m² for fluorescent luminaires and 3.71 W/m² – 1.65 W/m² for the LEDs, depending on the dimming level. UGR values of both installations were at about the same level.

## Conclusions

Case study showed that LED luminaires can achieve similar glare results than fluorescent luminaires, although measured LED luminaires had lower luminous efficacy than the measured fluorescent luminaire.
## 10.11 Case study 10: Factory in Netherlands

- Place: Netherlands

- Building type: Industry, assembly area

- Contact: Henri Juslén (Philips)

### Place description

The study area was an assembly area of the luminaire factory located in the Netherlands.
Figure 10-42 shows the area.

<figure><img src="image_223.png" /><figcaption>Figure 10-42. One of the assembly tables of the study.</figcaption></figure>

### Participants and work description

A total of 42 persons were working in the test area (average age 42 years), 69% of them being female. The products assembled were different for the different workstations, but the tasks that had to be performed were quite similar for all assembly workstations. The subjects assembled luminaire components, such as the frame, the gear, and optical parts. Connecting the wires was visually the most demanding part of the work. The smallest diameter of white wire was 2mm and the diameter of unisoleted copper end 0.8 mm. White wires were connected to white connector blocks and lamp holders by screws or just pushing the wire into the hole. Participants had lot of freedom to perform the tasks in the way and order they felt to be most suitable for them. The viewing distance to the main tasks was below one meter. The reference area was located in the hall next to the test hall. Assembly area,
work and workers training and expertise were comparable to similar ones in the test hall. The reference hall could not be seen from the test hall. Disturbing reflections might have been produced in both halls. Light coming from luminaires might have reflected from reflective aluminium material handled every now and then.

## Lighting conditions

Originally the factory hall was equipped with lighting installation that provided uniform general lighting to the area (2*58 W, 4000 K). Only limited daylight via windows was available. However, daylight did not contribute to the general illuminance. The lighting was switched off at the end of the working day. The new lighting installation consists of the old reduced general lighting installation at ceiling level in combination with suspended localised lighting (low-glare luminaries, 2*54 W, 4000 K) above the main task areas. The general lighting was grouped in such a way that time switches switched it on in those areas only where work was actually being carried out. Two or three persons were working at one workplace, and they were able to switch off the localised lighting from the assembly line when they no longer needed it. The task area illuminances in the factory before and after the change are shown in Table 10-6.

<table><caption>Table 10-6. Horizontal and vertical illuminances (Eh and Ev) at the assembly tables and in the surrounding area.</caption><thead><tr><th rowspan="2">Type of installation</th><th colspan="2">General lighting</th><th colspan="2">Assembly tables</th></tr><tr><th>Eh (lx)</th><th>Ev (lx)</th><th>Eh (lx)</th><th>Ev (lx)</th></tr></thead><tbody><tr><td>Old installation</td><td>400 - 650</td><td>100 - 300</td><td>450 - 600</td><td>100 - 300</td></tr><tr><td>New installation</td><td>300 - 380</td><td>100 - 170</td><td>800 - 1300</td><td>250 - 500</td></tr></tbody></table>

## Procedure

Lighting was changed once and the lighting energy use, productivity and absenteeism were monitored before and after the change. Participants were informed that new lighting would be installed and they knew that their productivity would be measured all the time as always.

## Dependent variables

Energy use, productivity and absenteeism were monitored before and after the lighting change. Results have not been statistically tested because only before-and-after results were observed, many other variables might have had their effect, and significance testing would not make results any stronger.

## Results

Although the installed lighting electricity power was reduced by only 7% (from 45 kW to 42 kW), the energy consumption reduced by 39%, from 207 to 127 MWh/year. This reduction in energy consumption is mainly due to the fact that the localised lighting was switched on only when and where it was needed, and the reduced general lighting was grouped per larger working area, and was switched off automatically outside working hours.

The grouping of luminaires before the change was not fully in accordance with the working areas – the lighting in the area might have been on because the adjacent working area was occupied.
The productivity measurement system in the factory was changed in 2003. For this reason, the values for 2003 are not comparable with the later values and were thus not used. Table 10-7 shows changes in both productivity and absenteeism. The productivity in 2004, prior to the lighting change, has been set as a reference value, and changes after the installation of the new lighting are shown as percentages. Values from the reference hall have been shown in the same way, although there was no lighting change there. The productivity change in the test hall together with the lighting change was a 5.5% increase compared to a 1% decrease in the reference hall. Absenteeism was reduced by 2.5% in the test hall and increased by 0.4% in the reference hall.

<table><caption>**Table 10-7.** Changes in the productivity and absenteeism rate in both the test hall and the reference hall (NA means Not Available).</caption><thead><tr><th rowspan="2">Time period</th><th colspan="2">Productivity</th><th colspan="2">Absenteeism</th></tr><tr><th>Test hall</th><th>Reference hall</th><th>Test hall</th><th>Reference hall</th></tr></thead><tbody><tr><td>Week 26-52 (2003)</td><td>NA</td><td>NA</td><td>Reference</td><td>Reference</td></tr><tr><td>Week 01-20 (2004)</td><td>Reference</td><td>Reference</td><td>-5.80%</td><td>-0.60%</td></tr><tr><td>Week 26-52 (2004)</td><td>+5.50%</td><td>-1%</td><td>-8.30%</td><td>-0.20%</td></tr></tbody></table>

The main results of this study are (no statistical tests used):

- Productivity increased in test hall after the lighting change at the same time that the productivity of the reference (no lighting change) groups decreased slightly

- Absenteeism decreased in test hall after the lighting change and in reference hall (no lighting change) absenteeism slightly increased

## Discussion

The study showed that general lighting can be reduced by employing task lighting and an improved lighting control system. This can yield an increase in productivity and decrease in lighting energy consumption.

Improving the lighting in industry does not automatically mean using more energy. A strong conclusion regarding productivity changes in this type of before-and-after study should have been avoided. This is because keeping all variables controlled is practically impossible.
## 10.12 Case study 11: Factory in Italy

Place: Italy (Piemonte Region)

Building type: Industry, mechanic workshop

Contact: Simonetta Fumagali (ENEA Ispra)

This is an example extracted from a number of similar projects in Italy. In each project, energy consumptions are measured and related energy savings are directly calculated. In about already completed 500 analogous installations, average energy savings have been around 51%. Projects have been and are used within the Italian White Certificates Scheme.

### Place description

The example consists of lighting installations in a mechanic workshop in Piemonte Region, which was in testing phase in March 2008. The project requirement was to have the same illuminance as before the retrofit, but with the possibility to increase illuminance values. For this reason, the installed power has been increased (36 W lamps replaced with 58 W).

<figure><img src="image_224.png" /><figcaption>Figure 10-43. Dimensions of the building.</figcaption></figure>

### Luminaries description

The lighting installation consisted of regular array of 360 luminaries divided in 6 rows and 60 columns. Each luminaire consisted of two linear fluorescent lamps. Luminaries with electronic dimmable ballasts have been installed with the energy saving module for continuous monitoring of the energy consumption.

#### Lamps

- T8 linear fluorescent lamps

- power : 58 W

- luminous flux : 5200 lm

- CCT: 4000 K

- CRI: 85

- Ballast - electronic, dimmable (6-100%)

- Lighting control - photosensor

- Type of reflector - diffuser: polycarbonate, complex parabola reflector. LOR > 75
<figure><img src="image_225.png" /><figcaption>**Figure 10-44.** *The luminaire.*</figcaption></figure>

<figure><img src="image_226.png" /></figure>

<figure><img src="image_227.png" /><figcaption>**Figure 10-45.** *Inside the luminaire.*</figcaption></figure>

## Photometry of the luminaire

<figure><img src="image_228.png" /><figcaption>**Figure 10-46.** *Luminaire photometric characteristics (luminances (cd/m²) vs angles).*</figcaption></figure>

<figure><img src="image_229.png" /><figcaption>**Figure 10-47.** *Luminaire characteristics : Intensity diagram.*</figcaption></figure>
## Measurements

<figure><img src="image_230.png" /></figure>

<table><caption>**Figure 10-48. Illuminance on work plane, with the luminance at full power (isolux diagram).**</caption><thead><tr><th>Average</th><th>Maximum</th><th>Minimum</th><th>Uniformity</th></tr></thead><tbody><tr><td>Emed 318.15 lx</td><td>Emax 363.90 lx</td><td>Emin 183.91 lx</td><td>Emin/Emed= 0.58<br>Emin/Emax= 0.51<br>Emax/Emin= 1.98</td></tr></tbody></table>

Lighting power density=8.84 W/m²

Normalized power density = W/m² / 100 lx = 2.78 W/m². 100 lx

<figure><img src="image_231.png" /><figcaption>**Figure 10-49.** Example of dimming: depending on an external light contribution (simulating daylight), power and illuminance from the luminaire are shown. Total illuminance (external source and luminaire) is also shown.</figcaption></figure>
## 10.13 Case study 12: School - lighting refurbishment

Place: The Netherlands (Zwijndrecht)

Building type: Secondary school

Contact: Truus de Bruin-Hordijk (Faculty of Architecture, Technical University Delft, The Netherlands)

### Place description

Measurements were done in two classrooms 2.23 and 2.20. Classroom 2.23, which is facing North-West, is experienced as dark by teachers. Another classroom 2.20, which is facing South-East, is experienced bright by teachers. The judgement of the lighting expert is negative for classroom 2.23 and is neutral for classroom 2.20. Both classrooms have grey walls and much furniture in it (Figure 10-50). Dimensions of the classrooms are: 7.2 x 7.2 x 3 m³. These are normal standard dimensions for primary and secondary classrooms in The Netherlands.

<figure><img src="image_232.png" /><figcaption>**Figure 10-50.** Classroom 2.20, window side and corridor side.</figcaption></figure>

### Luminaries description

Both classrooms have six high-efficient surface-mounted luminaires with mirror reflector (Philips TCS298), each luminaire with one Philips TL5 HO 49 W/830 lamp (Figure 10-51) with electronic ballast. The illuminance on the work plane is 350 lx at full power. The school has replaced the old lamps and luminaires some years ago. The lamps were placed in two rows of three luminaires parallel to the window façade. The lamps were dimmable and have daylight sensors. There were also presence detectors in these classrooms (Figure 10-52). There was also asymmetric board lighting.

<figure><img src="image_233.png" /><figcaption>**Figure 10-51.** Philips TL5 lamp.</figcaption></figure>

<caption>**Figure 10-52.** New lighting installation.</caption>
## Access to daylight

The daylight factors were measured on 23 September 2008 by a (not complete) overcast sky (Figure 10-53).

Table 10-8 and 10-9 show the daylight situation of the classrooms with daylight factors measured on a regular grid on table height (0.75 m). Table 10-10 shows the daylight factors in the middle on the blackboard and the outer left and right part of the blackboard. Classroom 2.23 has a green chalk board, whereas classroom 2.20 has a white board.

<figure><img src="image_234.png" /><figcaption>Figure 10-53. The sky at the day of the measurements.</figcaption></figure>

<table><caption>Table 10-8. The daylight factors on student table height in classroom 2.23.</caption><thead><tr><th rowspan="2">daylight factor (%)</th><th rowspan="2"></th><th colspan="3">black board</th></tr><tr><th>chair teacher</th><th>2.2</th><th>0.56</th><th>0.30</th></tr></thead><tbody><tr><th rowspan="3">window zone</th><th>8.9</th><td>2.5</td><td>0.66</td><td>0.29</td></tr><tr><th>11.6</th><td>2.9</td><td>0.74</td><td>0.29</td></tr><tr><th>12.3</th><td>2.3</td><td>0.63</td><td>0.31</td></tr></tbody></table>

<table><caption>Table 10-9. The daylight factors on student table height in classroom 2.20.</caption><thead><tr><th rowspan="2">daylight factor (%)</th><th rowspan="2"></th><th colspan="3">white board</th></tr><tr><th>chair teacher</th><th>2.2</th><th>0.77</th><th>0.42</th></tr></thead><tbody><tr><th rowspan="3">window zone</th><th>8.3</th><td>2.4</td><td>0.88</td><td>0.4</td></tr><tr><th>8.5</th><td>2.7</td><td>0.86</td><td>0.46</td></tr><tr><th>8.8</th><td>2.3</td><td>0.72</td><td>0.34</td></tr></tbody></table>

The daylight factor is decreased below 0.5% on the corridor side of the classroom.

<table><caption>Table 10-10. The daylight factors (%) on the blackboards in the two classrooms.</caption><thead><tr><th>Board type</th><th>left</th><th>middle</th><th>right</th></tr></thead><tbody><tr><td>green chalk board 2.23</td><td>3</td><td>1</td><td>0.4</td></tr><tr><td>white board 2.20</td><td>2.4</td><td>0.82</td><td>0.38</td></tr></tbody></table>
Figures below show luminance pictures, taken with a luminance camera with a fish-eye lens, from the back-side of the classrooms. It shows the situation for a sitting student with eye level on 1.2 m. The figures show the daylight situation with and without electrical lighting.

<figure><img src="image_235.png" /><figcaption>**Figure 10-54.** *Classroom 2.23 without electrical lighting, seen from student position.*</figcaption></figure>

<figure><img src="image_236.png" /><figcaption>**Figure 10-55.** *Classroom 2.23 with electrical lighting, seen from student position.*</figcaption></figure>

<figure><img src="image_237.png" /><figcaption>**Figure 10-56.** *Classroom 2.20 without electrical lighting, seen from student position.*</figcaption></figure>

<figure><img src="image_238.png" /><figcaption>**Figure 10-57.** *Classroom 2.20 with electrical lighting, seen from student position.*</figcaption></figure>
Luminance images taken in the view of teacher standing in front of the class:

<figure><img src="image_239.png" /><figcaption>**Figure 10-58.** *Classroom 2.23 without electrical lighting, seen from teacher position.*</figcaption></figure>

<figure><img src="image_240.png" /><figcaption>**Figure 10-59.** *Classroom 2.23 with electrical lighting, seen from teacher position.*</figcaption></figure>

<figure><img src="image_241.png" /><figcaption>**Figure 10-60.** *Classroom 2.20 without electrical lighting, seen from teacher position.*</figcaption></figure>

<figure><img src="image_242.png" /><figcaption>**Figure 10-61.** *Classroom 2.20 with electrical lighting, seen from teacher position.*</figcaption></figure>

The luminance values in the windows of the classroom 2.23 are higher than in the windows of classroom 2.20, because of the presence of trees outside the classroom 2.20. That can explain the difference in the measured daylight factors, and so more energy savings are expected due to daylight sensors.

The luminance images illustrate how the automatic dimming of the electric lighting can compensate an asymmetrical day-light distribution on the work plane (windows zone/corridor zone), and on the blackboard.
## 10.14 Case study 13: School - bright classroom

Place: The Netherlands (Zwijndrecht)

Building type: Secondary school, new building

Contact: Truus de Bruin-Hordijk (Faculty of Architecture, Technical University Delft, The Netherlands)

### Place description

The school building of the case study 12 (Chapter 10.13) has a new part, where the classrooms are situated at the North-East side of the school. The study was done in the classroom 2.07. Teachers and lighting expert both experienced this classroom as bright. The lighting expert experienced the ambiance as a restful place for busy pupils because the uniformity of lighting and the shadowing is soft, as result of the reflections from all the white walls and ceiling. The dimensions of the classroom are 7.2 x 7.2 x 2.8 m³.

### Luminaires description

The classroom is new with a white ceiling with embedded luminaires (Figure 10-62). Six luminaires, two rows with three luminares, were placed parallel to the window facade. Each luminaire contains two Osram T8 36 W/830 lamps.

<figure><img src="image_243.png" /><figcaption>Figure 10-62. Photos of classroom.</figcaption></figure>

The illuminance on the work plane is 350 lx at full power. The energy-efficient system of the case study 12 (Chapter 10.13) was not placed in the new classrooms, because there was no longer governmental subsidy. There was no blackboard lighting because at the time of lighting installation the argument for not having blackboard lighting was that white-boards are used nowadays. The argument is valid, as we see in the differences between Figures 10-56 and 10-57 of the case study 12, white board has higher luminances. However, there was a green chalk board in the classroom 2.07.

The lamps were dimmable and the system is equipped with daylight sensors, but the daylight sensors were only in the luminaire row of the window zone. The classrooms were also equipped with occupancy detection.
Tables 10-11 and 10-12 show the daylight factors on work plane height and on the blackboard. The differences with the last case study are clear; the corridor zone has higher daylight factors, because there is more reflected light in classroom 2.07.

<table><caption>**Table 10-11.** *The daylight factors on student table height in classroom 2.07.*</caption><thead><tr><th rowspan="2">daylightfactor (%)</th><th rowspan="2"></th><th colspan="3">black board</th></tr><tr><th>chair teacher</th><th>2.6</th><th>1.1</th><th>0.90</th></tr></thead><tbody><tr><td rowspan="3">window zone</td><td>12.7</td><td>3.4</td><td>1.5</td><td>1.0</td></tr><tr><td>14.7</td><td>4.2</td><td>1.6</td><td>1.1</td></tr><tr><td>11.4</td><td>3.6</td><td>1.6</td><td>0.77</td></tr></tbody><tfoot><tr><td colspan="4"></td><td>corridor zone</td></tr></tfoot></table>

<table><caption>**Table 10-12.** *The daylight factors on the blackboard.*</caption><thead><tr><th>Board type</th><th>left</th><th>middle</th><th>right</th></tr></thead><tbody><tr><td>blackboard 2.07</td><td>3,4</td><td>1,7</td><td>1</td></tr></tbody></table>

Figures below show the luminance contrasts as seen from student and teacher's point of view, one case with only daylight and another with electric lighting switched on. The difference between the two situations of Figure 10-65 and 10-66 is low. The electrical lighting has a low impact because the level of daylight is high enough. There are no daylight sensors in the corridor zone, otherwise the sensors would have probably switched off all the electrical lighting.

The judgement of the lighting expert is that classroom has a good design. It is comfortable for teacher and student, and it is a bright and restful place. The school has done much for energy reduction by the placement of daylight sensors and occupancy detection and a good choice of materials for walls, ceiling and furniture. Further energy reduction might be realised by daylight sensors in the corridor zone, too.

<figure><img src="image_244.png" /><figcaption>**Figure 10-63.** *Classroom 2.07 without electrical lighting, seen from the student position.*</figcaption></figure>

<figure><img src="image_245.png" /><figcaption>**Figure 10-64.** *Classroom 2.07 with electrical lighting switched on, seen from the student position.*</figcaption></figure>

Figure 10-63 and 10-64 show the luminances of the room 2.07 without and with electrical lighting switched on, seen from the student position. One luminaire in the middle of the window zone is switched off by the daylight sensor.
<figure><img src="image_246.png" /><figcaption>**Figure 10-65.** Classroom 2.07 without electrical lighting, seen from the teacher position.</figcaption></figure>

<figure><img src="image_247.png" /><figcaption>**Figure 10-66.** Classroom 2.07 with electrical lighting switched on, seen from the teacher position.</figcaption></figure>

Figures 10-65 and 10-66 show the luminances of the room 2.07 without and with electrical lighting switched on, seen from the teacher position. The daylight sensor has switched off all the luminaries in the window zone.
## 10.15 Case study 14: Primary school - bright classroom

Place: The Netherlands (Leidschenveen)

Building type: Primary school

Contact: Truus de Bruin-Hordijk (Faculty of Architecture, Technical University Delft, The Netherlands)

### Place description

Measurements were done in two classrooms: one facing north, and the other facing south. Both classrooms have lower windows for view and upper windows for daylight access (Figure 10-67).

<figure><img src="image_248.png" /><figcaption>Figure 10-67. Photos of the building and classrooms.</figcaption></figure>

<figure><img src="image_249.png" /></figure>

<figure><img src="image_250.png" /></figure>

### Luminaries description

There are six surface-mounted luminaires (Figure 10-68), the same as in case study 13 (Chapter 10-14) but here the luminaires are perpendicular to the window façade. Only the two luminaires nearest the window façade have daylight sensors. There is no blackboard lighting.

<figure><img src="image_251.png" /><figcaption>Figure 10-68. Luminaire.</figcaption></figure>
## Measurements

Table 10-13 shows the daylight situation in the North classroom on 24 December 2003. It was a cloudy, rainy day. The daylight factors at a regular grid at the task field of the classroom and at a 0.5 m edge around the task field are shown in the table.

<table><caption>**Table 10-13.** The daylight factors at work plane height.</caption><thead><tr><th></th><th>a</th><th>b</th><th>c</th><th>d</th><th>e</th><th>f</th></tr></thead><tbody><tr><th>1</th><td>2.58</td><td>3.10</td><td>2.62</td><td>1.97</td><td>2.82</td><td>1.70</td></tr><tr><th>2</th><td>3.97</td><td>3.80</td><td>3.86</td><td>3.25</td><td>3.39</td><td>2.22</td></tr><tr><th>3</th><td>1.64</td><td>1.89</td><td>1.93</td><td>1.76</td><td>1.73</td><td>1.48</td></tr><tr><th>4</th><td>0.98</td><td>1.12</td><td>1.15</td><td>1.07</td><td>0.92</td><td>0.70</td></tr><tr><th>5</th><td>0.81</td><td>0.80</td><td>0.86</td><td>0.80</td><td>0.76</td><td>0.68</td></tr><tr><th>6</th><td>0.67</td><td>0.82</td><td>0.80</td><td>0.88</td><td>0.90</td><td>0.76</td></tr></tbody></table>

As the façade is composed by lower windows and upper windows, the daylight factors are quite uniform on the task field, with a minimum of about 0.7 (bright walls and ceiling). Figures 10-69 and 10-70 show the luminance measurements, done with a spot luminance meter, in a North and a South classroom.

Sun shine reaching the blackboard and resulting high contrasts and shadows can be noticed in the Figure 10-70. As the luminaires are perpendicular to the façade, the fluorescent lamps are less hidden by the louvers for a pupils looking at the blackboard.

<figure><img src="image_252.png" /><figcaption>**Figure 10-69.** Luminance measurements in north classroom.</figcaption></figure>

<caption>**Figure 10-70.** Luminance measurements in south classroom.</caption>

## Interviews

The electric lighting is switched on the whole day in winter and about 3-4 hours a day in summer. Teachers experienced the north classroom as dark and dull.
## 10.16 Case study 15: Primary school Beveren-Leie - lighting refurbishment

Place: Belgium (Waregem)

Building type: School

Contact: A. Deneyer (Belgian Building Research Institute)

### Place description

There are 300 pupils in this primary school. The aim of the refurbishment was to improve the performance of the lighting installation. At first, a test room has been refurbished, and then six other classes followed the same way.

Before refurbishment, classrooms were equipped with linear fluorescent opalescent luminaires with poor CRI, that were driven with electromagnetic ballasts. There was no special lighting fixture for the black board.

<figure><img src="image_253.png" /></figure>

<figure><img src="image_254.png" /><figcaption>**Figure 10-71.** *Picture of the test room before refurbishment.*</figcaption></figure>

<figure><img src="image_255.png" /><figcaption>**Figure 10-72.** *Photo of the test room after refurbishment.*</figcaption></figure>
Daylight enters from one side of the classroom which is shaded with “californian screens”. The eight old luminaires were replaced by six new luminaires. An extra three new luminaires were added so as to lit the blackboard.

## Luminaire description

- aluminium high efficiency louvers

- T5 fluorescent lamps of 54 W

- electronic ballast & CRI >80

### Blackboard luminaire:

- asymmetrical optic

- T5 fluorescent lamps of 35 W

- estimated power density: 10 W/m²

<figure><img src="image_256.png" /><figcaption>Figure 10-73. Luminaire.</figcaption></figure>

## Measurements

### Old installations

- average illuminance on the work plane: 230 lx

- normalized lighting power density: 6.6 W/m².100 lx

### New installations

- average illuminance on the work plane at full power: 502 lx

- normalized lighting power density: 2 W/m².100 lx

Increase in illuminance levels on the work plane: 100%

Total reduction in lighting energy consumption: 33%

For the seven classrooms:

- total investment: 10001.25 €

- estimated benefits from energy consumption: 569.46 €/year

- estimated benefits from maintenance: 174.71 €/year

- time to retrofit: 13.4 years

## Occupant satisfaction

Teachers were amazed that they could use the overall surface of the blackboard, as it is lit properly.
## 10.17 Case study 16: High school of St Eligius - lighting refurbishment

Place: Belgium (Anverse)

Building type: School

Contact: A. Deneyer (Belgian Building Research Institute)

### Place description

<figure><img src="image_257.png" /><figcaption>**Figure 10-74.** *Photo of classroom before refurbishment.*</figcaption></figure>

In the high school of Saint Eligius, students can study until they are 18 years old.

The school had 25 years old lighting fixtures. The old lighting system had T12 fluorescent tubes (38mm) with electromagnetic ballasts and opalescent optic diffuser.

In order to reduce the lighting energy consumption and to improve the colour rendering of the lighting it was decided to change the luminaires in 2007.

<figure><img src="image_258.png" /></figure>

<figure><img src="image_259.png" /><figcaption>**Figure 10-75.** *Photo of classroom after refurbishment.*</figcaption></figure>

The height of the classroom was 3.5 m. The numbers of luminaires were kept the same and the new luminaires were installed in the same place as old installations. Hence, there was no need to change the wiring. Refurbishment was done in 17 classrooms, one corridor and the stairs of the building.
## Luminaire description

- T5 fluorescent lamp of 28 W power per luminaire

- electronic ballast & CRI >80

- high efficiency aluminium louvers

- estimated lighting power density: 8 W/m²

<figure><img src="image_260.png" /><figcaption>Figure 10-76. Luminaire.</figcaption></figure>

## Measurements

### Old installations

- average illuminance on the work plane: 330 lx

- normalized lighting power density: 7.7 W/m².100lx

### New installations

- average illuminance on the work plane at full power: 404 lx

- normalized lighting power density: 2 W/m².100lx

Increase in illuminance levels on the work plane: 22%

Total reduction in lighting energy consumption: 74%

### For the 17 classrooms

- total investment: 32308 €

- estimated benefits / energy consumption: 2041.68 €/year

- estimated benefits / maintenance: 242.62 €/year

- time Retrofit: 14.1 years
## 10.18 Case study 17: Primary School in Roma (1)

- Place: Italy (Roma)

- Building type: school (Primary School)

- Contact: Fabio Bisegna (Università di Roma "La Sapienza")

### Place description

The school is situated in Rome, in the South-Eastern part of the city. Measurements have been done in only one classroom that is facing South-East. The classroom has a particular shape (it is more or less a square but without a corner). The dimensions of the main sides are 7.05 m x 7.33 m, the ceiling height is 3.25 m and the work plane height is 0.72 m. The classroom has a white ceiling and light cream-coloured walls. Furniture was present when the measurements were carried out.

<figure><img src="image_261.png" /><figcaption>Figure 10-77. Classroom: window side.</figcaption></figure>

<figure><img src="image_262.png" /><figcaption>Figure 10-78. Classroom: corridor side.</figcaption></figure>

### Luminaries description

- lamp type: fluorescent lamp

- CRI: between 80 and 90

- CCT: 4000K

- lighting control: manual on/off

- reflector-diffuser: translucent acrylic opal glass

- total luminous efficacy (including ballast and luminaire) at full power: 75 lm/W

- brand: Durlum

<figure><img src="image_263.png" /><figcaption>Figure 10-79. Photometry of the luminaire.</figcaption></figure>
## Measurements

There are four surface-mounted luminaries in each room. Each luminaire is composed by two T8 36W fluorescent lamps and a translucent acrylic opal glass. Lamps are not dimmable. Luminaires are placed in two rows of two luminaires parallel to the window façade. There are not additional lamps to illuminate the blackboard zone. Estimated installed lighting power density is 7.6 W/m². Illuminance measurements were done for a grid of points traced in the classroom. The average illuminance with artificial lighting at full power was measured to be 284.6 lx with uniformity 0.7.

<figure><img src="image_264.png" /><figcaption>**Figure 10-80.** Illuminances on the work plane due to daylight: measured on 21th December at 12 am under overcast sky conditions (external illuminance 5000 lx).</figcaption></figure>

<figure><img src="image_265.png" /><figcaption>**Figure 10-81.** Illuminance values on the work plane at full power (artificial light).</figcaption></figure>

## Study on occupant satisfaction

*Number of users:* 20 pupils and 1 teacher

*Length of the test period (season concerned):* winter

*Real schedules:* from 8:15 am to 4:15 pm

*type of work:* reading on blackboard, paying attention to the teacher, writing, reading, drawing, looking to the paper (student tasks), writing on blackboard, talking to students, paying attention to working students, preparing lessons (teacher tasks)

## Study results

*Positive or negative judgement by users concerning their working area:* pupils were complaining about sun during the mid hours of the day

*Global positive or negative judgement by users concerning the artificial lighting:* positive
*Control quality of both artificial and daylight:* artificial lighting system in the classroom distributes light uniformly, doesnot cause glare and respects the regulations values, windows provide sufficient natural lighting and daylight factor value is respected as well.

*Visual comfort, light and space, warm/cool:* pupils were complaining about the sun in the mid hours of the day, complains about overheating in summer, enough light in the classroom
## 10.19 Case study 18: Primary School in Roma (2)

- Place: Italy (Roma)

- Building type: school (Primary School)

- Contact: Fabio Bisegna (Università di Roma "La Sapienza")

### Place description

The school is located in Rome, in the South-Eastern part of the city. One classroom, facing South-West, has been measured. The classroom has a white ceiling and light yellow walls. The measurements were taken with furniture inside the classroom. The classroom has more or less a square shape with dimensions of 6.10 m x 6.60 m and ceiling height 3.15 m.

<figure><img src="image_266.png" /><figcaption>Figure 10-82. Classroom: corridor side.</figcaption></figure>

<figure><img src="image_267.png" /><figcaption>Figure 10-83. Classroom: window side.</figcaption></figure>

### Luminaries description

- lamp type: fluorescent lamp

- CRI: between 80 and 90

- CCT: 4000 K

- lighting control: manual on/off

- reflector-diffuser: aluminium parabolic louvre

- brand: Regiolux

<figure><img src="image_268.png" /><figcaption>Figure 10-84. Photometry of the luminaire.</figcaption></figure>
<figure><img src="image_269.png" /><figcaption>**Figure 10-85.** Luminaires.</figcaption></figure>

## Measurements

There are four surface-mounted luminaires. Each luminaire is composed by two T8 36 W fluorescent lamps. Light distribution of the luminaire is directed by aluminium parabolic louvers and its matt anodizing is for representative illumination requirements. Lamps have only manual on/off lighting control system. Luminaires were placed in two rows of two luminaires each, parallel to the window façade. The average illuminance on the work plane is 350 lx at full power. There is no additional blackboard lighting. The installed lighting power density is 8.54 W/m². Points of measurement were arranged cross-shaped with each row placed in the middle of the classroom. The average illuminance with artificial lighting at full power was measured to be 350 lx with uniformity 0.8.

<figure><img src="image_270.png" /><figcaption>**Figure 10-86.** Illuminance on the work plane due to daylight: measured on 18th November at 12 am under sunny sky conditions (external illuminance 48000 lx).</figcaption></figure>

<figure><img src="image_271.png" /><figcaption>**Figure 10-87.** Illuminance values on the work plane at full power (artificial light).</figcaption></figure>
**Study on occupant satisfaction**

*Number of users:* 23 pupils and 1 teacher

*Length of the test period (season concerned):* winter

*Real schedules:* from 8:15 am to 4:15 pm

*Type of work:* reading on blackboard, paying attention to the teacher, writing, reading, drawing, looking to the paper (student tasks), writing on blackboard, talking to students, paying attention to working students, preparing lessons (teacher tasks)

**Study results and discussion**

*Positive or negative judgment by users concerning their working area:* kids were complaining about the sun in the central hours of the day and had to move their desks

*Global positive or negative judgment by a user concerning the artificial lighting:* positive

*Visual comfort, light and space, warm/cool:* kids complaining about the sun in the central hours of the day, overheating in summer, sufficient light in the classroom

Artificial lighting system distributes light uniformly, does not cause glare and respects the regulations values. However, much more for energy reduction could be done by providing the artificial system with daylight sensors and presence detection. The materials and colors of walls and ceiling and their reflectance coefficients are ideal to reduce electricity consumption by providing a good distribution of light and a greater amount of reflective light. Windows provide sufficient natural lighting and daylight value is respected as well. A further improvement could be reached by the placement of daylight systems but could solve some problems such as overheating in summer and glare in the mid hours of the day.
## 10.20 Case Study 19: Energy saving potential in the University

Place: Poland

Building type: Service Sector, school

Contact: Zbigniew Mantorski (WASKO S.A., Gliwice, Poland)

### Place description

The site of the study is a five storey building of the Faculty of Electrical Engineering, Silesian University of Technology. The building was built in 1963.

<figure><img src="image_272.png" /><figcaption>Figure 10-88. South eastern façade.</figcaption></figure>

<figure><img src="image_273.png" /><figcaption>Figure 10-89. Auditorium.</figcaption></figure>

<figure><img src="image_274.png" /><figcaption>Figure 10-90. Classroom.</figcaption></figure>

### Luminaires description

<figure><img src="image_275.png" /><figcaption>Figure 10.91 Luminaires placement (half of the 3rd floor).</figcaption></figure>
<table><caption>**Table 10-14.** *Installed lamps*</caption><thead><tr><td>Types of sources</td><td>Number</td><td>Installed Power [W]</td></tr></thead><tbody><tr><td>Fluorescent lamps</td><td>1029</td><td>39470</td></tr><tr><td>Compact Fluorescents</td><td>54</td><td>1193</td></tr><tr><td>Incandescent lamps (GLS)</td><td>126</td><td>19800</td></tr><tr><td>Halogen lamps</td><td>32</td><td>2630</td></tr><tr><td>Incandescent lamps with reflectors</td><td>3</td><td>130</td></tr><tr><td>Discharge lamps (Mercury, Sodium)</td><td>8</td><td>1910</td></tr></tbody></table>

Total installed power: 65193 W

Minimum lighting power density: 2.33 W/m² in corridors

Maximum power density: 22 W/m² in some rooms with incandescent lamps

<figure><img src="image_276.png" /><figcaption>**Figure 10-92.** *Pictures of luminaires.*</figcaption></figure>

**Measurements:**

The building is used between 8:30 am. and 6 pm. to 8 pm., except in the weekends. Some of the lighting in the corridors remains switched on all the time for security reasons. The total energy consumption of the building is 99.4 MWh per year, of which lighting represents 37%.

<table><caption>**Table 10-15.** *Energy consumption.*</caption><thead><tr><td>Type of source</td><td>Energy consumption [MWh/year]</td><td>% of the total consumption</td></tr></thead><tbody><tr><td>Fluorescent Lamps</td><td>22.66</td><td>60.5</td></tr><tr><td>Sodium and Mercury Lamps</td><td>7.28</td><td>19.44</td></tr><tr><td>Incandescent Lamps (GLS)</td><td>7.51</td><td>20.05</td></tr></tbody></table>

The results of the photometric measurements in auditorium:

- Emean= 350 lx

- Uniformity= 0.58

The illuminance in the pedagogic rooms was found to be lower than the standard levels. The uniformity ratio in most rooms was between 0.5 and 0.7.
<figure><img src="image_277.png" /><figcaption>Figure 10-93. Sample of illuminance measurements (Auditorium).</figcaption></figure>

<table><caption>Table 10-16. Potential decreases in lighting energy consumption with different actions.</caption><thead><tr><td>Actions</td><td>Potential Benefits</td></tr></thead><tbody><tr><td>Replacement of incandescent lamps by compact fluorescent lamps</td><td>6.44 MWh/year</td></tr><tr><td>Replacement of old T 12 fluorescent lamps by new T8 lamps</td><td>1.44 MWh/year</td></tr><tr><td>Replacement of outdoor Sodium and Mercury lamps by new more efficient ones</td><td>3.93 MWh/year</td></tr></tbody></table>

The potential decrease in lighting energy consumption (without occupancy and dimming control) is 11.81 MWh per year (31.5% of the current electric energy consumption for lighting).
## 10.21 Case Study 20: Renovation of an auditorium

Place: Finland (Helsinki)

Building type: Auditorium, academic

Contact: Eino Tetri (University of Technology, Helsinki, Lighting Unit)

### Description of the initial condition

<figure><img src="image_278.png" /><figcaption>Figure 10-94. Picture before the retrofit.</figcaption></figure>

#### Luminaries:

- A 40 years old installation with 87 luminaries

- Each luminaire with 2 T12 lamps of 40 W each (CRI=63).

- Possibility of dimming.

### Description of the new configuration

<figure><img src="image_279.png" /><figcaption>Figure 10-95. Picture after the retrofit.</figcaption></figure>

#### Luminaries:

- The old luminaries changed by 69 new ones

- Each luminaire with 2 T5 lamps of 49 W each (CRI > 80)

- Ballast: DALI

- In each luminaire: one lamp with CCT = 4200 K, the other with CCT = 17000 K
Measurements

<table><caption>Table 10-17. Measurement results.</caption><thead><tr><th></th><th>Average Illuminance (lx)</th><th>Average Luminance (cd/m²)</th><th>UGR</th><th>Total power (W)</th><th>LOR</th><th>CCT (K)</th><th>CRI</th></tr></thead><tbody><tr><td>Before</td><td>428</td><td>45</td><td>14</td><td>10571</td><td>0.39</td><td>4000</td><td>63</td></tr><tr><td>After</td><td>974</td><td>103</td><td>21</td><td>7383</td><td>0.74</td><td>4200<br>17000</td><td>&gt;80</td></tr></tbody></table>

Luminaires were replaced with new T5-lamp luminaires with electronic ballasts. The old luminaires were very inefficient (LOR 39%) compared to the new luminaires (LOR 74%). T5 lamps operate with electronic ballasts, thus decreasing the power losses of ballast and also improving the efficiency of the gas discharge.

The installed power is reduced significantly while the average illuminance is doubled. The energy savings were 27% when compared to old system at full power. Lamps are dimmed most of the time with pre-set scenes. For instance there are preset scenes for lecture, lecture with video, exam, etc. One week measurement indicated 55% energy savings, in comparing the measurement values with the energy consumption of the old system at full power.
## 10.22 Case Study 21: Replacement of metal halide lamp by induction lamp

- Place: Korea

- Building type: Gymnasium

- Contact: Yming Chen (Shanghai Hongyuan Lighting&Electric Equipment Co. Ltd)

### Place description

<figure><img src="image_280.png" /><figcaption>**Figure 10-96.** *Shape of the building.*</figcaption></figure>

<figure><img src="image_281.png" /><figcaption>**Figure 10-97.** *Picture of the room before and after the replacement.*</figcaption></figure>
## Luminaires description

<figure><img src="image_282.png" /><figcaption>Figure 10-98. Luminaires description.</figcaption></figure>

<table><caption>Table 10-18. Comparison between the two sources (Metal Halide & Induction Lamp).</caption><thead><tr><td>Lamp</td><td>Voltage (V)</td><td>Power (W)</td><td>Luminous flux (lm)</td><td>Efficacy (lm/W)</td><td>Tc (K)</td><td>CRI</td><td>Lifetime (h)</td></tr></thead><tbody><tr><td>MH</td><td>220</td><td>400</td><td>34 000</td><td>85</td><td>4300</td><td>65</td><td>12 000</td></tr><tr><td>IL</td><td>220</td><td>200</td><td>19 600</td><td>98</td><td>4100</td><td>80</td><td>60 000</td></tr></tbody></table>

MH= Metal Halide IL= Induction Lamp
## Measurements

<table><caption>Table 10-19. Comparison between the two facilities.</caption><thead><tr><td>Items</td><td>Old system</td><td>New system</td></tr></thead><tbody><tr><td>Light source &amp; power</td><td>MHL 400 W</td><td>LVD 200 W</td></tr><tr><td>Lamp efficacy</td><td>85 lm/W</td><td>98 lm/W</td></tr><tr><td>CRI</td><td>67</td><td>83</td></tr><tr><td>Unit fixture power</td><td>440 W</td><td>210.7 W</td></tr><tr><td>Fixture number</td><td>68</td><td>66</td></tr><tr><td>Average ground illuminance</td><td>420 lx</td><td>580 lx</td></tr><tr><td>Life time</td><td>12 000 h</td><td>60 000 h</td></tr><tr><td>Total power consumption</td><td>29.92 kW</td><td>13.9 kW</td></tr></tbody></table>

### For Metal Halide Lamp:

- lighting power density = $37.4 W/m^2$

- normalized lighting power density = $8.9 W/m^2 \cdot 100 lx$

### For Induction Lamp:

- lighting power density = $17.37 W/m^2$

- normalized lighting power density = $3 W/m^2 \cdot 100 lx$

In addition to the improvement in luminous efficacy of lamp, we can notice the large improvement brought by the optic efficiency.
10-23 Appendix 1. Data list for case studies.

<table><thead><tr><th></th><th>Minimum required</th><th>More if possible</th></tr></thead><tbody><tr><td rowspan="7">Conception</td><td colspan="2" style="text-align: center; font-weight: bold;">- Place description</td></tr><tr><td>Site: country, city, building type</td><td>Characterization of the access to daylight</td></tr><tr><td>Map, ceiling & work plane height</td><td>Possible troubles caused by daylight</td></tr><tr><td>Luminaires positions</td><td>Schedules of users (including cleaners)</td></tr><tr><td>Photography</td><td></td></tr><tr><td>W/m² installed</td><td></td></tr><tr><td colspan="2" style="text-align: center; font-weight: bold;">- Luminaires description</td></tr><tr><td>Lamp type, RCI, CT</td><td>Photometry of the luminaire</td></tr><tr><td>Ballast</td><td>Geometry of the luminaire</td></tr><tr><td>Lighting control</td><td>Photography of the luminaire ON and OFF</td></tr><tr><td>Type of reflector-diffuser</td><td>Catalog price</td></tr><tr><td>Global efficiency of one luminaire at full power (lm/W) announced</td><td></td></tr><tr><td>Brand</td><td></td></tr><tr><td rowspan="7">Results</td><td colspan="2" style="text-align: center; font-weight: bold;">- Measures</td></tr><tr><td>Illuminances on the work plane full power</td><td>Watt at full power (with a wattmeter), cos φ</td></tr><tr><td>Average, Maximum, Minimum, Uniformity</td><td>If dimmable: graph lx vs Watt</td></tr><tr><td>Illuminances and statistics on the work plane if not at full power</td><td>Ratio between surfaces (horizontal & vertical) of luminances or illuminances</td></tr><tr><td>Glare indicator (max luminance, UGR...)</td><td>Materials photometry, kWh/(m².year)</td></tr><tr><td colspan="2" style="text-align: center; font-weight: bold;">- Interviews</td></tr><tr><td>Global positive or negative judgment by a user concerning is working area</td><td>Number of users, length of the test period, seasons concerned</td></tr><tr><td>Global positive or negative judgment by a user concerning the artificial lighting</td><td>Real schedules, glasses, known eyes difficulties, type of work (screen ?...)</td></tr><tr><td>Type of the precedent lighting design</td><td>Control quality of both artificial and day light<br>Visual comfort, light and space, warm / cool<br>Design of the luminaire<br>Point of view of the maintenance</td></tr></tbody></table>
# Chapter 11: Technical potential for energy efficient lighting and savings

## Topics covered

<table><tr><td>11</td><td>Technical potential for energy efficient lighting and savings</td><td>315</td></tr><tr><td>11.1</td><td>Light consumption in 2005</td><td>315</td></tr><tr><td>11.2</td><td>Estimated electric light consumption in 2015/2030</td><td>318</td></tr><tr><td>11.3</td><td>Estimated electric energy consumption for lighting in 2005/2015/2030</td><td>320</td></tr><tr><td>11.4</td><td>Conclusions</td><td>322</td></tr><tr><td></td><td>References</td><td>323</td></tr></table>
# 11 Technical potential for energy efficient lighting and savings

## 11.1 Light consumption in 2005

The estimated global electric light consumption is calculated as quantity of light Q, which is the luminous flux integrated over duration of time. The unit of quantity of light is lumen-hour, lmh. The luminous flux is produced by different lamp types. Since light cannot be stored, the light consumption and production are always equal; the light produced by lamps is immediately consumed by the users.

The average share of electric light consumption per person can be expressed as the ratio between light consumption and total population in a particular year.

$$Q_p = \frac{Q}{P_p} \qquad (11-1)$$

where

Qp Light consumption per person Mlmh/person,a

Q Light consumption, Plmh/a

Pp Population of the world, billion

The electric energy consumption for lighting can be expressed as the ratio between the average consumption of light per person and luminous efficacy of a particular lamp.

$$E_p = \frac{Q_p}{\eta} \qquad (11-2)$$

where

E<sub>p</sub> Electric energy consumption per person, MWh/person,a

Q<sub>p</sub> Light consumption per person, Mlmh/person,a

η Lamp luminous efficacy, lm/W

The electric energy consumption per person can also be expressed in kWh/person,a (in that case the resultant amount must be multiplied by 1000). Table 11-1 shows electric energy consumption for residential lighting calculated for different lamp types. The calculation is based on estimated light consumptions. The population of the world was 6.7 billion in 2005. (IEA 2006)

<table><caption>**Table11-1.** Estimated electric light consumption for different lamp types for residential lighting and calculated light and energy consumptions per person. (IEA 2006)</caption><thead><tr><th rowspan="2">Lamp type</th><th>Luminous efficacy</th><th>Light consumption</th><th>Light consumption per person</th><th>Energy consumption per person</th></tr><tr><th>η [lm/W]</th><th>Q [Plmh]</th><th>Q<sub>p</sub> [Mlmh/person,a]</th><th>E<sub>p</sub> [kWh/person,a]</th></tr></thead><tbody><tr><td>Incandescent</td><td>12</td><td>8.5</td><td>1.3</td><td>105.7</td></tr><tr><td>Tungsten halogen</td><td>20</td><td>1.3</td><td>0.2</td><td>9.7</td></tr><tr><td>CFL</td><td>45</td><td>1.9</td><td>0.3</td><td>6.3</td></tr><tr><td>LFL</td><td>66</td><td>8.2</td><td>1.2</td><td>18.5</td></tr><tr><td>Total</td><td></td><td>19.9</td><td>3.0</td><td>140.3</td></tr></tbody></table>

In the residential sector, the amount of light produced by incandescent lamps is approximately equal to that by fluorescent lamps. However, the annual electric energy consumption per person of incandescent lamps is approximately six times more than that of fluorescent lamps. In 2005, the shares of halogen and CFL lamps in both the light consumption and energy consumption were relatively low. The total annual light consumption in residential sector was approximately 3.0
Mlmh/person,a and the electric energy consumption was 140 kWh/person,a.

High intensity discharge lamps are dominant in the outdoor lighting sector. The total light consumption in outdoor lighting in 2005 was estimated to be 2.3 Mlmh/person,a and the electric energy consumption was correspondingly 46.6 kWh/person,a (Table 11-2).

<table><caption>**Table 11-2.** Estimated electric energy consumption for outdoor lighting. (IEA 2006)</caption><thead><tr><th>Lamp type</th><th>Luminous efficacy η [lm/W]</th><th>Light consumption Q [Plmh]</th><th>Light consumption per person Q<sub>P</sub> [Mlmh/person,a]</th><th>Energy consumption per person E<sub>P</sub> [kWh/person,a]</th></tr></thead><tbody><tr><td>HID</td><td>50</td><td>15.6</td><td>2.3</td><td>46.6</td></tr><tr><td>Total</td><td></td><td>15.6</td><td>2.3</td><td>46.6</td></tr></tbody></table>

In the industrial sector, fluorescent lamps and HID lamps were dominant and resulted in total estimated light consumption of 5.7 Mlmh/person,a and in electric energy consumption of 96.9 kWh/person,a (Table 11-3).

<table><caption>**Table 11-3.** Estimated electric energy consumption for industrial lighting. (IEA 2006)</caption><thead><tr><th>Lamp type</th><th>Luminous efficacy η [lm/W]</th><th>Light consumption Q [Plmh]</th><th>Light consumption per person Q<sub>P</sub> [Mlmh/person,a]</th><th>Energy consumption per person E<sub>P</sub> [kWh/person,a]</th></tr></thead><tbody><tr><td>LFL</td><td>66</td><td>23.7</td><td>3.5</td><td>53.6</td></tr><tr><td>HID</td><td>50</td><td>14.5</td><td>2.2</td><td>43.3</td></tr><tr><td>Total</td><td></td><td>38.2</td><td>5.7</td><td>96.9</td></tr></tbody></table>

In the commercial sector, fluorescent lamps represent the largest share of electric light consumption, and also electric energy consumption. However, although incandescent lamps represent a small share of light consumption, their electric energy consumption was almost 50% of that of the fluorescent lamps.

<table><caption>**Table 11-4.** Estimated electric energy consumption for commercial lighting. (IEA 2006)</caption><thead><tr><th>Lamp type</th><th>Luminous efficacy η [lm/W]</th><th>Light consumption Q [Plmh]</th><th>Light consumption per person Q<sub>P</sub> [Mlmh/person,a]</th><th>Energy consumption per person E<sub>P</sub> [kWh/person,a]</th></tr></thead><tbody><tr><td>Incandescent</td><td>12</td><td>3.9</td><td>0.6</td><td>48.5</td></tr><tr><td>Tungsten halogen</td><td>20</td><td>1.3</td><td>0.2</td><td>9.7</td></tr><tr><td>CFL</td><td>45</td><td>3.9</td><td>0.6</td><td>12.9</td></tr><tr><td>LFL</td><td>66</td><td>44.1</td><td>6.6</td><td>99.7</td></tr><tr><td>HID</td><td>50</td><td>6.2</td><td>0.9</td><td>18.5</td></tr><tr><td>Total</td><td></td><td>59.4</td><td>8.9</td><td>189.4</td></tr></tbody></table>

Compared to the other sectors, the commercial sector accounted for the highest share of both light consumption and electric energy consumption, Table 11-5.
<table><caption>**Table 11-5.** Estimated total electric energy consumption. (IEA 2006)</caption><thead><tr><th>Lighting sector</th><th>Light consumption Q [Plmh]</th><th>Light consumption per person Q<sub>P</sub> [Mlmh/person,a]</th><th>Energy consumption per person E<sub>P</sub> [kWh/person,a]</th></tr></thead><tbody><tr><td>Residential</td><td>19.9</td><td>3.0</td><td>140.3</td></tr><tr><td>Outdoor</td><td>15.6</td><td>2.3</td><td>46.6</td></tr><tr><td>Industrial</td><td>38.2</td><td>5.7</td><td>96.9</td></tr><tr><td>Commercial</td><td>59.4</td><td>8.9</td><td>189.4</td></tr><tr><td>Total</td><td>133.1</td><td>19.9</td><td>473.1</td></tr></tbody></table>

In Figure 11-1, with reference to the tables presented above, the share of light consumption in each sector for the different lamp types is represented.

<figure><img src="image_283.png" /><figcaption>**Figure 11-1.** Total worldwide light consumption in different sectors by lamp type in 2005. (IEA 2006)</figcaption></figure>

In Figure 11-2, with reference to the tables presented before, the proportion of electric energy consumption of the different lamp types for each sector is represented. The high share of energy consumption of the incandescent lamps, due to their low luminous efficacy, is very distinctive.
<figure><img src="image_284.png" /><figcaption>**Figure 11-2.** Estimated electric energy consumption in different sectors by lamp type in 2005. (IEA 2006)</figcaption></figure>

In Figure 11-3, the share of electric light consumption in 2005 through different lamp types, irrespective of sector, is summarized and represented.

<figure><img src="image_285.png" /><figcaption>**Figure 11-3.** Electric light consumption through different lamp types in 2005. (IEA 2006)</figcaption></figure>

The largest share of light consumption, 11.3 Mlmh/person,a, is produced by linear fluorescent lamps (LFL) followed by HID lamps with 5.4 Mlmh/person,a. Incandescent lamps have a comparably lower share of the light consumption.

## 11.2 Estimated electric light consumption in 2015/2030

The prognosis in the following is based on the work of the IEA ECBCS Annex 45. Figure 11-4 represents an estimation of the development of the global electric light consumption in 2015 and 2030 compared to the situation in 2005. Generally, in comparison to 2005, an increase in the light consumption of approximately 25% is to be expected by 2015. It is estimated, however, that due to improved facility utilization factor (light output ratio multiplied by room utilance, LOR x U) of 20% and decreased mean operating time (factor of 0.8, due to improved daylight utilization and control systems), this will be compensated, Table 11-6. The increase in utilization factor will decrease the need for light production since light is wasted less in the luminaire and light is also
directed more efficiently to the task area. Despite the increased light demand (increased by 25% in 2015 compared to 2005), the total light produced by lamps is reduced. This is due to increased efficiency of luminaires and room and lighting design, and also due to increased use of daylight and lighting control systems.

<table><caption>**Table 11-6.** Comparison of different factors in 2015 and 2030, compared to 2005.</caption><thead><tr><th></th><th>2015</th><th>2030</th></tr></thead><tbody><tr><td>Increase in total light consumption</td><td>25%</td><td>55%</td></tr><tr><td>Facility utilization improvement</td><td>20%</td><td>25%</td></tr><tr><td>Operating time factor</td><td>0.80</td><td>0.70</td></tr><tr><td>Resulting total light consumption</td><td>0.80</td><td>0.81</td></tr></tbody></table>

The total light consumption, for instance in 2015, is 100% x 1.25 x 0.8 x 0.8 = 80% compared to 2005. At the same time, it is expected that there will be a clear reduction in the use of incandescent lamps due to legislation (step by step abolition of incandescent lamps), an increase in the use of CFLs and LED lamps, and a replacement of T12 and T8 lamps by T5 lamps. It is estimated that by 2030, incandescent lamps will account only for a very small share of the lamps in use. LEDs will represent a large share of the market and their share will increase substantially, as shown also in Figure 11-4.

Compared to 2005, it is estimated that there will be an additional light demand (light consumption by end user) of 55% in 2030. Due to improved facility utilization factor of 25% and decreased mean operating time (factor of 0.7, due to improved daylight utilization and control), the overall electric light consumption will therefore be approximately the same as in 2015. Part of the electric light consumption is replaced by daylight.

<figure><img src="image_286.png" /><figcaption>**Figure 11-4.** Estimated electric light consumption through different lamp types in 2005, 2015 and 2030.</figcaption></figure>

Figure 11-5 shows a summarized representation of the electric light consumption through different lamp types in 2005 together with the expected development for 2015 and 2030. Part of the increase in light consumption is covered by the increases use of daylight and lighting control systems. Other part of the increase in light consumption is covered by the improved facility utilization factor. Due
to this the light production of the lamps can be decrease and at the same time the end-user will get the same amount of light on the task area.

<figure><img src="image_287.png" /><figcaption>**Figure 11-5.** Development of electric light consumption through different lamp types [Mlmh/person,a] from 2005 to 2030. The facility utilization and daylight + control indicate the shares of light consumption covered by improved facility utilization and through the use of daylight and control systems.</figcaption></figure>

## 11.3 Estimated electric energy consumption for lighting in 2005/2015/2030

If we use the following plausible assumptions (Table 11-7) of the lamp luminous efficacies (lm/W), we can calculate the electric energy consumption (kWh/person,a) from the electric light consumption (Mlmh/person,a). The luminous efficacies are average values of all the lamps on the market. The case LED2 forecasts fast development of the luminous efficacy of LEDs and also their quick breakthrough on the market. Since the average luminous efficacy of LED2 is 160 lm/W, the maximum should be much higher. According to Navigant (2009) the white LED package luminous efficacy targets in 2015 are 200 lm/W in laboratory, and 188 lm/W commercially. The practical achievable maximum package luminous efficacies are about 220 lm/W depending on the CCT. (Navigant 2009)
<table><caption>**Table 11-7.** Expected lamp luminous efficacies in year 2005, 2015 and 2030. LED2 estimates a fast development of the luminous efficacy of LEDs and quick breakthrough on the market.</caption><thead><tr><th>Luminous efficacy [lm/W]</th><th>Incandescent</th><th>Tungsten halogen</th><th>CFL</th><th>LFL</th><th>HID</th><th>LED</th><th>LED2</th></tr></thead><tbody><tr><td>2005</td><td>12</td><td>20</td><td>45</td><td>66</td><td>50</td><td>60</td><td>60</td></tr><tr><td>2015</td><td>12</td><td>25</td><td>50</td><td>86</td><td>65</td><td>80</td><td>100</td></tr><tr><td>2030</td><td>12</td><td>30</td><td>55</td><td>90</td><td>80</td><td>120</td><td>160</td></tr></tbody></table>

In Figure 11-6, with reference to Figure 11-4 and Table 11-7, the proportion of electric energy consumption of the different lamp types in 2005, 2015 and 2030, irrespective of sector, is summarized.

A significant reduction in electric energy consumption by incandescent lamps in 2015 is to be expected due to legislative actions. Also, the energy consumption of fluorescent lamps reduces, as the luminous efficacy of lamps in use will increase due to replacement of obsolete technology. As the share of halogen lamps remains relatively unchanged, but their luminous efficacy slightly increases, their energy consumption will slightly decrease. This is similar with the HID lamps. The share of CFLs in light consumption will increase and at the same time their luminous efficacy will increase, resulting in overall lower total energy consumption.

Furthermore, in 2030, there will be a further reduction in the use of incandescent lamps due to the almost complete replacement by halogen lamps and CFLs. The use of fluorescent lamps and HID lamps will reduce due to replacement of obsolete technology. LEDs will penetrate further into the market and will have a corresponding share of the market.

<figure><img src="image_288.png" /><figcaption>**Figure 11-6.** Status of electric energy consumption of lighting through different lamp types in 2005/2015/2030.</figcaption></figure>

Figure 11-7 shows the reduction of electric energy consumption in 2015 and 2030 compared to 2005. The reduction is based on the replacement of inefficient lamps and also on the increased luminous efficacy of all lamp types (Table 11-7). The total annual light consumption is taken from Figure 11-5.

The scenarios for 2015B and 2030B are based on the assumption of LEDs taking over the lamp
market faster than in scenarios 2015 and 2030. Compared to scenario 2015, scenario 2015B is based on the assumptions: incandescent lamps 25%, CFLs 50% and LFLs 75% of the light consumption of scenario 2015. The light consumption remains the same and the gap is filled by LEDs. The luminous efficacy of LEDs in scenario 2015B is 100 lm/W.

In scenario 2030B incandescent and halogen lamps are practically vanished from the market, CFLs produce only one quarter and LFL and HID lamps half of the light consumption shown on Figure 11-5. Instead, a major part of the light consumption is produced by LEDs. Incandescent and tungsten halogen lamps and certain CFLs (screw cap lamp base) can be replaced by LED-lamps at short time, but LFL and HID lamps are used in dedicated luminaires and the annual renovation rate of old installations is only 3 to 5%. Compared to scenario 2030, the light consumption remains the same in scenario 2030B, but the electric energy consumption reduces since the average luminous efficacy of the LEDs in use in 2030 would be 160 lm/W (Table 11-7).

<figure><img src="image_289.png" /><figcaption>**Figure 11-7.** Scenarios of electric energy consumption for lighting in 2005, 2015 and 2030 by different lamp types. The scenarios 2015B and 2030B are based in increased use of LEDs.</figcaption></figure>

## 11.4 Conclusions

The forecast of the electric energy consumption for lighting is based on the assumptions

- increasing light consumption of 25% (2015) and 55% (2030) by end user

- increasing efficiencies of the installations of 20% (2015), and 25% (2030) (light output ratio of luminaires and room utilance)

- reduced operating time factors of 0,80 (2015), and 0,70 (2030) by daylight utilisation and controls

- phasing out incandescent (mostly until 2015), T12 (2015) and T8 (2030) lamps, replaced by CFL, LFL T5 and LED lamps.

- in scenarios 2015B and 2030B LEDs will take over the lamp market quickly and their luminous efficacy is developing fast.

Based on these assumptions we can expect a decrease in electrical energy consumption for lighting down to less than a half or even to one third of the consumption in 2005 (see Figure 11-7). These assumptions and also the forecast of lamp efficacies (Table 11-7) are rather conservative for the industrialised countries (scenarios 2015 and 2030). The remaining unknown is the development in China, India and Africa, that will define if the predicted energy savings become reality.
## References

IEA 2006. International Energy Agency. Light's Labour's Lost. IEA Publications, France. 360 p.

Navigant Consulting, Radcliffe Advisors and SSLS, I., 2009. /Multi-Year Program Plan FY'09-FY'15 - Solid-State Lighting Research and Development. /U.S. Department of Energy. 193 p.
# Chapter 12: Proposals to upgrade recommendations and codes

## Topics covered

12 Proposals to upgrade lighting standards and recommendations .................................................... 327

12.1 A difficult trade-off between energy conservation and satisfaction of human needs .. 327

12.2 The origins of lighting standards and recommendations .................................................... 327

12.3 Challenges for new lighting standards and recommendations................................................ 328
# 12 Proposals to upgrade lighting standards and recommendations

## 12.1 A difficult trade-off between energy conservation and satisfaction of human needs

The growing concern of energy performance in buildings leads to the search for a “reasonable” optimum in installed lighting power. Because of this gathering of robust evidence of fundamental minimum requirements in lighting is needed. On one hand, visual requirements related to visual acuity lead to rather high illuminance levels (500 lx to read), and even higher if we consider the population above 60 years of age. On the other hand, general ambient lighting is more related to balance of luminances, absence of glare, a minimum illuminances for displacement or filing documents (minimum illuminance around 100-200 lx).

## 12.2 The origins of lighting standards and recommendations

The evolution of standards has, at large, followed the development of lighting technologies, cost of lighting and the increased scientific understanding of vision. The lighting recommendations have dealt with the optimum visual performance, appropriate light distribution, glare reduction, color rendering, in relation to the available technology. Targets for the above mentioned values were defined at performance levels, achievable at reasonable costs of equipment and energy. In the second half of the 20th century, the availability of powerful and inexpensive light sources such as tubular triphosphor fluorescent lamps led to an increase in the recommended illuminance levels. Later, the development of VDU workstations led to increased demands for glare control and avoidance of light reflection from the screens.

At the end of the 20th century, several research results suggested a more global approach for interior lighting design. For example:

- More concern was given to the satisfaction of occupants over long term, and their general rating of the indoor environment.

- Relation of humans to light was addressed in the physiological side, with the discovery of a novel light receptor in the eye, related to the non-visual effects of light, and managing our circadian rhythms.

- Several studies identified the potential for energy conservation through higher use of daylight, and development of energy efficient lighting design and control strategies.

- The contribution of electric lighting to the overall energy use of buildings was identified, along with its impact on requirements on air conditioning, cooling and heating.

- New technologies were proposed, leading to a potential increase in the performance of light sources, luminaires and systems. A great leap forward was taken by the lighting industry in laying the foundation for developments of new light sources like high pressure sodium lamps, metal halide lamps, improved phosphorus for fluorescent lamps, etc.

- A better understanding of the environmental impacts of lighting components led to the progressive development of pollutant reduction and increased activities for recycling.

- The development in the solid-state lighting technology has brought new light sources (LEDs) in the market at break neck speed. By today, LEDs are a viable option also for general lighting and soon it will be completing in energy-efficiency with the traditional light sources.
## 12.3 Challenges for new lighting standards and recommendations

The difference between the lighting standards and recommendations in different countries has been attributed to the economical context and the geographical zone of the country. The differences are related to the living standard, technological and economical capacity and also to the influence of specific research or institutional organizations. A major future development of lighting recommendations is that they should address many other topics beyond the visual specifications associated to the satisfaction of specific activities. Recent research results suggest that the following considerations are to be included in future indoor lighting recommendations:

- Minimum illuminance on work plane in office lighting. A value of 500 lx is proposed by CEN Norm EN 12464-1 (item 3.2 and 3.4). The current recommendations concern mainly the level of illuminances on the desk area, but it should be remembered that what people perceive are luminances, i.e. light reflected from the surfaces. Thus, it should be kept in mind that the required minimum illuminance is also related to the values of the luminances in the visual field. Therefore, discussions about the 500 lx minimum value should integrate a more luminance based approach. Also, the individual and age-related differences in the required light levels should be considered, for example aged workers may need more light than 20-year old workers.

- Since reading and writing is performed on a small part of the desk, and since a computer screen is now the standard of a workplace, it is suggested that the recommended illuminance of 500 lx should be achieved only on the reading and writing area of the desk (see Figure 12-1). This is being discussed within CEN TC 169 WG2.

<figure><img src="image_290.png" /><figcaption>**Figure 12-1.** Possible distribution of illuminances on work plane for optimal visual performance and energy efficiency.</figcaption></figure>

- The rest of the work plane would then require a lower illuminance. Recommendations suggest not to go to a value less than about two third of the values on the task (EN 12464-1 proposes 300 lx for work places). Discussions about minimum illuminance values for the rest of the room
for (not reading) would be useful.

- Uniformity of illuminance. According to CEN Norm EN 12464-1 minimum threshold of 0.7 is required on the task, and 0.5 for the immediate surroundings. Not much is said for the rest of the room. Tests performed on observers demonstrate that they respond positively to various kind of *modulation* of the illuminance distribution. Variations of illuminances in spaces, in ratio of 1 to 2 or 1 to 3 appear appropriate, as long as they are correctly managed. Discussions on the evolution of recommendations require evidence of the acceptable limits on this aspect.

- Indoor lighting design is based largely on providing more or less uniform levels of illuminances in the room, while the perception of the luminous environment is related mainly to light reflected from surfaces i.e. luminances. Thus innovative lighting design methods could be introduced which give a high priority to the quality of the luminous environment as our eyes perceive it. The possible obstacles and constraints that are set by the current regulations for horizontal illumination levels should be identified, and ways for designing and implementing more innovative lighting solutions should be sought. Figure 12-2 presents three different lighting installations. Configuration 1 is without task lighting and configurations 2 and 3 with task lighting. The daylight contribution is different in different cases. Table 12-1 presents the installations in detail. Both the electrical lighting design (general/task lighting) and the use of daylight have a major impact on lighting quality and energy-efficiency.

<figure><img src="image_291.png" /><figcaption>**Figure 12-2.** Three different possible configurations for lighting with vertical the same illuminance on task (500 lx) but various illuminances in the room (200, 300 and 500 lx). Minimum illuminance is 100lx in all cases.</figcaption></figure>

- Glare control. Recommendations include specifications on glare control, but not on overhead glare. Luminaires with high luminance light sources such as CFL, T5 or spot lamps (halogen, LEDs) have been found to be uncomfortable if the sources are visible, even if they are located above the head of the observers (Figure 12-3) recommendations need to be updated to propose more restrictions of luminances and higher angles of observation.
<figure><img src="image_292.png" /><figcaption>**Figure 12-3.** Overhead glare issues: discomfort glare occurs even when the luminaire is just above the occupant or, if luminaire luminance is high (above 14 000 cd/m²). Such can be the case with unshaded CFLs, LEDs, halogens and T5 fluorescent lamps.</figcaption></figure>

- Reduction of the size of light sources (compact HID lamps, LEDs) may lead to increased risk of glare. Standards and recommendations should be adapted accordingly.

- Luminance distribution. Balance of luminances in the field of view is expressed in the recommendations in order to reduce fatigue and eye stress. Recent findings suggest that luminances of vertical surfaces facing the occupants also play a role in visual stimulation and alertness (see CIE Div 3 TC work: Luminance Based Lighting Design).

- The quality of light spectra is required with a minimum Color Rendering Index CRI of 80. The light sources typically used in office lighting have good CRI. The CIE general CRI has its limitations. The shortcomings of the CRI may become evident when applied to LED light sources due to their peaked spectra. The CIE (CIE 2007) recommends the development of a new color rendering index (or a set of new color rendering indices), which should be applicable to all types of light sources including white LEDs

- Daylighting is suggested, but lighting recommendations do not specify recommended values of daylight factors or other parameters. This is a field where practical metrics could be developed, and mentioned in recommendations.

- Glare from windows is not addressed, and there could be recommendations for sunshading systems to prevent glare.
<table><caption>**Table 12-1.** Comparison of the energy performances of the three lighting configurations in Figure 12-2.</caption><thead><tr><th>Feature</th><th>Configuration 1</th><th>Configuration 2</th><th>Configuration 3</th></tr></thead><tbody><tr><td>Power density of ceiling luminaire</td><td>11 W/m<sup>2</sup></td><td>4.4 W/m<sup>2</sup></td><td>6.6 W/m<sup>2</sup></td></tr><tr><td>Power density of task focused lighting</td><td></td><td>1.7 W/m<sup>2</sup></td><td>1.7 W/m<sup>2</sup></td></tr><tr><td>Room area</td><td>12 m<sup>2</sup></td><td>12 m<sup>2</sup></td><td>12 m<sup>2</sup></td></tr><tr><td>Annual burning hours of ceiling luminaire</td><td>2000 h</td><td>2000 h</td><td>2000 h</td></tr><tr><td>Annual burning hours of task focused lighting</td><td></td><td>1600 h</td><td>1600 h</td></tr><tr><td>Energy consumption without daylight</td><td>264 kWh/a</td><td>138 kWh/a</td><td>191 kWh/a</td></tr><tr><td>Energy consumption with daylight (30%)</td><td>185 kWh/a</td><td></td><td></td></tr><tr><td>Energy consumption with daylight (70%)</td><td></td><td>41 kWh/a</td><td></td></tr><tr><td>Energy consumption with daylight (50%)</td><td></td><td></td><td>95 kWh/a</td></tr><tr><td>Energy density without daylight</td><td>22 kWh/ m<sup>2</sup>.a</td><td>11.5 kWh/ m<sup>2</sup>.a</td><td>15.9 kWh/ m<sup>2</sup>.a</td></tr><tr><td>Energy density with daylight</td><td>15.4 kWh/ m<sup>2</sup>.a</td><td>3.41 kWh/ m<sup>2</sup>.a</td><td>7.91 kWh/ m<sup>2</sup>.a</td></tr></tbody></table>
# 13 Summary and conclusions

Lighting is a large and rapidly growing source of energy demand and greenhouse gas emissions. At the same time the savings potential of lighting energy is high even with the current technology, and there are new energy efficient lighting technologies coming on the market.

Currently, more than 33 billion lamps operate worldwide, consuming more than 2 650 TWh of energy annually, which is 19% of global electricity consumption. The total lighting-related carbon dioxide (CO₂) emissions were estimated to be 1900 million tons in 2005, which was about 7% of the total global CO₂ emissions from the consumption and flaring of fossil fuels. The global electricity consumption for lighting is distributed approximately 28% to the residential sector, 48% to the service sector, 16% to the industrial sector, and 8% to street and other lighting. In the industrialized countries, national electricity consumption for lighting ranges from 5% to 15%, on the other hand, in developing countries the value can be even higher than 80% of the total electricity usage.

More than one quarter of the world's population is still without access to electric networks and uses fuel-based lighting to fulfil its lighting needs. The fuel-based light sources include candles, oil lamps, kerosene lamps, biogas lamps, propane lamps, and resin-soaked twigs. While electrification is increasing in the developing countries, it is more and more important to adopt energy efficient light sources and lighting systems both in the developing and industrialised countries. Solid-state lighting combined with renewable energy sources has already reached some remote villages in developing countries, where it brings affordable, safe, healthy, and energy efficient lighting to the people.

The amount of consumption of light in the world has constantly been increasing. The amount of global consumption of light in 2005 was 134.7 petalumen hours (Plmh). The average annual per capita light consumption of people with access to electricity is 27.6 Mlmh, whereas the people without access to electricity use only 50 klmh.

Any attempt to develop an energy efficient lighting strategy should, as the first priority, guarantee that the quality of the luminous environment is as high as possible. The results presented in this Guidebook demonstrate that this is achievable, even with high savings in electricity consumption. Through professional lighting design energy efficient and high quality lighting can be reached. Better lighting quality does not necessarily mean higher consumption of energy. While it is important to provide adequate light levels for ensuring optimized visual performance, there are always light levels above which a further increase in the light level does not improve performance.

The increased possibilities to control both the intensity and spectrum of light sources should allow the creation of more appropriate and comfortable luminous environments. Also, the use of lighting control systems, based on presence detection and the integration of electrical light with daylight, can lead to substantial energy savings. New technologies such as LEDs offer high flexibility in the control of light spectra and intensities, which enhance their attractiveness besides their growing luminous efficacy.

It is important to search for technological lighting solutions which meet human needs with the lowest impact on the environment during their life cycle. The environmental impacts of lighting include production, operation and disposal of lamps and related materials. The total lighting energy used depends, in addition to the used lighting equipment (lamps, ballasts, drivers, luminaires, control devices), also on the lighting design and the room characteristics.
There are several characteristics that need to be considered when choosing the lamp. These include e.g. luminous efficacy (lm/W), lamp life (h), spectrum and other color characteristics (CRI, CCT), dimming characteristics and the effects of ambient circumstances on the lamp performance. Concerning all lamp types, the best lamp, if coupled with poor or incompatible luminaire, ballast or driver, loses most of its advantages.

It is foreseen that LEDs will revolutionize the lighting practices and market in the near future. The benefits of LEDs are their long lifetime, color-mixing possibilities, spectrum, design flexibility and small size, easy control, and dimming. For LEDs huge technological development is expected to continue. According to US DOE, the maximum luminous efficacy of phosphor converted cool-white LEDs is expected be around 200 lm/W by 2015, while the luminous efficacy of warm white LEDs is expected to be above 140 lm/W. The given values are for high-power LEDs with 1 mm² chip size at a 350 mA drive current at 25°C ambient temperature without driver losses. The special features of LEDs provide luminaire manufacturers to develop new type of luminaires and designers to adopt totally new lighting practices. The key success factor for the broad penetration of general lighting market by LEDs is a light source with high system efficacy and high quality at moderate prices. One barrier to the broad penetration of the market by LED applications is the lack of industrial standards.

Currently, there is a global trend to phase out inefficient light sources from the market through legislation and voluntary measures. Two EU regulations for lighting equipment entered into force in April 2009 and they will result in gradual phasing out of e.g. incandescent, mercury and certain inefficient fluorescent and HID lamps from the EU market. Similar legislative actions are carried around the world: Australia has banned the importation of incandescent lamps from February 2009, and USA has enacted the Energy Independence and Security Act of 2007 that phases out incandescent lamps in 2012-2014. Also other countries and regions have banned, are on their way to ban, or are considering to ban inefficient light sources.

Innovative and efficient lighting technology is already available on the market; very often, however, the current installations are dominated by inefficient technology that does not utilize control systems, sensors, or efficient light sources. Today, 70% of the lighting energy is consumed by inefficient lamps. Low retrofitting rates in the building sector (and thus also in lighting installations) are the main barrier to the market penetration of adequate and modern lighting technologies. It is estimated that 90% of all buildings are more than 20 years old, and 70-80% are older than 30 years. In order to increase the knowledge and use of energy efficient lighting, it is essential to increase dissemination and education, as well as to get new standards and legislation.

Energy efficient lighting also includes considerations of the control of light and the use of daylight. A sustainable lighting solution includes an intelligent concept, high quality and energy efficient lighting equipment suitable for the application, and proper controls and maintenance. Further energy savings can be achieved with smart lighting control strategies. Today, the most common form of control (the standard wall switch) is being replaced by automatic components which are based on occupancy or daylight harvesting. Examples of this technology are occupancy sensors which turn the lights off when the area is unoccupied, time-based controls and the dimmer plus photocell combination. These can lead to energy savings that vary from 10% with a simple clock to more than 60% with a total integrated solution (occupancy plus daylight plus HVAC).

For economic evaluation of different lighting solutions, a life cycle cost analysis has to be made. Usually, only the initial (investment) costs are taken into account. People are not aware of the variable costs, which include energy costs, lamp replacement costs, cleaning
and reparation costs. In commercial buildings very often the variable costs are paid by others who rent the flat, and the initial (investment) costs are usually paid by the investor who makes the system decisions. The energy costs of a lighting installation during the whole life cycle are very often the largest part of the whole life cycle costs. It is essential that in future lighting design practice, maintenance schedules and life cycle costs will become as natural as e.g. illuminance calculations already are.

The aim of an optimum lighting design is to achieve certain appearances and, at the same time, to fulfill the fundamental physiological and psychological visual requirements and to ultimately put the whole thing into effect in an energy efficient manner. LEDs allow for completely new designs and architectures for lighting solutions, thus opening a new and wide field of creativity for all lighting professionals. At the same time, some old rules and standards for a good lighting design are no more applicable to LEDs (e.g. glare assessment, color rendering, light distribution, etc.).

The expert survey conducted during 2006-2007 within the Annex 45 work indicated that among the lighting community there is a lack of knowledge of the characteristics and performance of new lighting technologies. Another major topic that was raised was the lack of awareness of the total life-cycle costs. The survey also indicated resistance to the adoption of new technology.

Commissioning is done for the number of different reasons: clarifying building system performance requirements set by the owner, auditing different judgments and actions by the commissioning related parties in order to realize the performance, writing necessary and sufficient documentation, and verifying that the system enables proper operation and maintenance through functional performance testing. Commissioning should be applied through the whole life cycle of the building. The Guidebook presents an example of commissioning process applied to a lighting control system.

Case studies of different types of lighting systems were conducted within the Annex 45 work. The studies were conducted for twenty buildings, most of which were offices and schools. In office buildings different case studies showed that it is possible to obtain both good visual quality and low installed power for lighting. In offices and schools it is possible to reach the normalized power density of 2 W/m²,100 lx (even 1.5 W/m²,100 lx in some office cases) with the current technology. It was found that the use of lighting control system to switch the lights on and off based on occupancy sensors can reduce the lighting energy intensity of office buildings. Additionally, the use of dimming and control sensors for the integration of daylight and artificial light can yield to further energy savings. The case studies show examples of LEDs in task, general and corridor lighting. The LED lighting requires a new approach to lighting design. The case studies show that LEDs can be used in the renovation of lighting in commercial buildings.

In 2005 the incandescent lamps dominate the lighting energy consumption in the residential sector. The total annual light consumption in residential sector is only 3 Mlmh/person and the electric energy consumption is as high as 140 kWh/person. In the commercial sector the annual light consumption is almost three times higher (8.9 Mlmh/person), while the energy consumption is only 35% higher than in the residential sector. This is due to the use of more efficient lighting technology in the commercial sector. Compared to 2005, it is estimated that there will be an additional light demand (light consumption by end user) of 25% by 2015, and of 55% by 2030. This will, however, be compensated by facility utilization factor (improved luminaire light output ratio and room utilance) and decreased mean operating time (improved daylight utilization and control systems).
It is expected that the share of different light sources producing the total electrical light output will change in the future. This is due to the development of light source luminous efficacies, legislative measures to phase out inefficient light sources in many countries, and the penetration of the lighting market by LEDs. In the Annex 45 work forecasts for the lighting energy consumption were made. On the basis of the most optimistic scenario, according to which LEDs will take over the lamp markets quickly and their luminous efficacy is developing fast, the lighting energy consumption in 2015 is reduced to half, and in 2030 to one third, of the values in 2005. The remaining unknown is the developments in China, India and Africa, which will define whether the predicted energy savings become reality.

The evolution of standards has, at large, followed the development of lighting technologies, cost of lighting and the increased scientific understanding of vision. The recommended values of illuminances have followed the development of light sources. For instance, in the second half of the 20th century the evolution of fluorescent lamps led to increases in the recommended illuminance levels. The difference between the lighting standards and recommendations in different countries has been attributed to the economical context and the geographical zone of the country. The current indoor lighting design is based largely on providing more or less uniform levels of illuminances in the room, while the perception of the luminous environment is related mainly to light reflected from surfaces i.e. luminances. Thus innovative lighting design methods could be introduced which give a high priority to the quality of the luminous environment as our eyes perceive it. Both the electrical lighting design and the use of daylight have a major impact on lighting quality and energy efficiency. The present lighting recommendations do not specify recommended values of daylight factors or other daylight parameters. This is a field where practical metrics could be developed and mentioned in the recommendations. Reduction of the size of light sources (compact HID lamps, LEDs) may lead to increased risk of glare. Standards and recommendations should be adapted accordingly. One parameter to assess the quality of lighting is the color rendering index CRI. The current CRI is not suitable to LEDs due to their peaked spectra. The CIE recommends the development of a new color rendering index (or a set of new color rendering indices), which should be applicable to all types of light sources including white LEDs. A major future development of lighting recommendations is that beyond the visual requirements they should address also the non-visual effects of light.

There is a significant potential to improve energy efficiency of old and new lighting installations already with the existing technology. The energy efficiency of lighting installations can be improved with the following measures:

- the choice of lamps. Incandescent lamps should be replaced by CFLs, infrared coated tungsten halogen lamps or LEDs, mercury lamps by high-pressure sodium lamps, metal halide lamps or LEDs, and ferromagnetic ballasts by electronic ballasts;

- usage of controllable electronic ballasts with low losses;

- the lighting design. Use of efficient luminaires and localized task lighting;

- the control of light with manual dimming, presence sensors and dimming according to daylight;

- the usage of daylight;

- the use of high-efficiency LED-based lighting systems.

The Annex 45 suggests that clear international initiatives (by the IEA, EU, CIE, IEC, CEN and other legislative bodies) are taken to:

- upgrade lightings standards and recommendations

- integrate values of lighting energy density (kWh/m², a) into building energy codes;

- monitor and regulate the quality of innovative light sources

- pursue research into fundamental human requirements for lighting (visual and non-
visual effects of light)

- stimulate the renovation of inefficient old lighting installations by targeted measures

The introduction of more energy efficient lighting products and procedures can, at the same
time provide better living and working environments, and also contribute in a cost-effective
manner to the global reduction of energy consumption and greenhouse gas emissions.
# 14 Participants and corresponding members

## Australia

Queensland University of Technology
* Steve Coyne

## Austria

Bartenbach LichtLabor GmbH
* Wilfried Pohl

Zumtobel Lighting
* Peter Dehoff

## Belgium

Belgian Building Research Institute
* Arnaud Deneyer

Université Catholique de Louvain
* Magali Bodart

## Canada

University of British Columbia
* Lorne Whitehead

* Michele Mossman

* Alexander Rosemann

## China

Fudan University
* Dahua Chen

* Edward Yuan

* Yuming Chen

Shanghai Hongyuan Lighting & Electric Equipment Co
* Aiqun Wang

## Finland

Aalto University

* Liisa Halonen

* Eino Tetri

* Pramod Bhusal

## France

Ecole Nationale des Travaux Publics de l'État (ENTPE)
* Marc Fontoynont

CSTB

* Mireille Jandon

* Nicolas Couillaud

* Christophe Martinsons

Ingélux Consultants

* Laurent Escaffre

Lumen Art

* Susanne Harchaoui

ADEME

* Herve Lefebvre

Veolia Environnement

* Ahmad Husaunndee

## Germany

Technische Universität Berlin
* Heinrich Kaase

## Italy

Università di Roma “La Sapienza”
* Fabio Bisegna

ENEA Ispra

* Simonetta Fumagalli

Politechnico di Torino
* Anna Pellegrino
* Valentina Serra

## Japan

National Institute for Land and Infrastructure Management
* Yasuhiro Miki

Tokai University
* Toshie Iwata

## The Netherlands

Philips Lighting Controls

Delft University of Technology
* Truus de Bruin-Hordijk

* Regina Bokel

* M. van der Voorden

## Norway

NTNU and SINTEF
* Barbara Matusiak

* Tore Kolås

BAS Bergen School of Architecture
* Lars Bylund

## Poland

WASKO S.A.
* Zbigniew Mantorski

## Russia

Russian Lighting Research Institute (Svetotehnika)
* Julian Aizenberg

## Singapore

National University of Singapore
* Lee Siew Eang

## Sweden

School of Engineering, Jönköping
* Nils Svendenius

WSP Ljusdesign
* Peter Pertola

## Switzerland

Solar Energy and Building Physics Lab, EPFL
* Jean-Louis Scartezzini

* Nicolas Morel

* David Lindelöf

* Friedrich Linhart

University of Applied Sciences of Western Switzerland
* Gilles Courret

## Turkey

Istanbul Technical University
* Dilek Enarum

## United Kingdom

Helvar
* Trevor Forrest

## USA

Lawrence Berkeley National Laboratory
* Stephen Selkowitz
**15 Glossary**

**adaptation:** the process by which the state of the visual system is modified by previous and present exposure to stimuli that may have various luminances, spectral distributions and angular subtanses.

**ballast:** device connected between the supply and one or more discharge lamps which serves mainly to limit the current of the lamp(s) to the required value.

**brightness:** attribute of a visual sensation according to which an area appears to emit more or less light.

**British thermal unit (Btu):** unit of energy equivalent to 1055 joules.

**bulb:** transparent or translucent gas-tight envelope enclosing the luminous element (s).

**colour rendering:** effect of a light source on the colour appearance of objects by conscious or subconscious comparison with their colour appearance under a reference light source.

**colour rendering index:** measure of the degree to which the psychophysical colour of an object illuminated by the test light source conforms to that of the same object illuminated by the reference light source, suitable allowance having been made for the state of the chromatic adaptation.

**colour temperature:** temperature of a Planckian radiator whose radiation has the same chromaticity as that of a given stimulus; unit: K.

**compact fluorescent lamp (CFL):** a fluorescent lamp with bent tubes to reduce the size of the lamp.

**contrast:** assessment of the difference in appearance of two or more parts of a field seen simultaneously or successively (hence: brightness contrast, luminance contrast, colour contrast, simultaneous contrast, successive contrast, etc.).

**correlated colour temperature:** the temperature of the Planckian radiator whose perceived colour most closely resembles that of a given stimulus at the same brightness and under specified viewing conditions; unit: K.

**daylight factor:** ratio of the illuminance at a point on a given plane due to the light received directly or indirectly from a sky of assumed or known luminance distribution, to the illuminance on a horizontal plane due to an unobstructed hemisphere of this sky, excluding the contribution of direct sunlight to both illuminances.

**direct lighting:** lighting by means of luminaires having a distribution of luminous intensity such that the fraction of the emitted luminous flux directly reaching the working plane, assumed to be unbounded, is 90 % to 100 %.

**disability glare:** glare that impairs the vision of objects without necessarily causing discomfort.

**discharge lamp:** lamp in which the light is produced, directly or indirectly, by an electric discharge through a gas, a metal vapour or a mixture of several gases and vapours.

**discomfort glare:** glare that causes discomfort without necessarily impairing the vision of the objects.

**ecological footprint:** a measure of how much biologically productive land and water an individual, population or activity requires to produce all the resources it consumes and to absorb the waste it generates using prevailing technology and resource management practices; measured in global hectares.
**electroluminescence:** luminescence caused by the action of an electric field in a gas or in a solid material.

**emission:** release of radiant energy.

**flicker:** impression of unsteadiness of visual sensation induced by a light stimulus whose luminance or spectral distribution fluctuates with time.

**fluorescence:** photoluminescence in which the emitted optical radiation results from direct transitions from the photo-excited energy level to a lower level, these transitions taking place generally within 10 nanoseconds after the excitation.

**fluorescent lamp:** a discharge lamp of the low pressure mercury type in which most of the light is emitted by one or several layers of phosphors excited by the ultraviolet radiation from the discharge.

**general lighting:** substantially uniform lighting of an area without provision for special local requirements.

**general lighting service (GLS) lamp:** always used to refer to a standard incandescent light-bulb.

**glare:** condition of vision in which there is discomfort or a reduction in the ability to see details or objects, caused by an unsuitable distribution or range of luminance, or to extreme contrasts.

**greenhouse gases:** gases in the atmosphere that contribute to the greenhouse effect by absorbing infrared radiation produced by solar warming of the Earth's surface.

**high intensity discharge lamp:** an electric discharge lamp in which the light-producing arc is stabilized by wall temperature and the arc has a bulb wall loading in excess of 3 watts per square centimetre.

**high pressure sodium lamp:** a high intensity discharge lamp in which the light is produced mainly by radiation from sodium vapour operating as a partial pressure of the order of 10 kilopascals.

**illuminance:** quotient of the luminous flux incident on an element of the surface containing the point, by the area of that element; unit: lx.

**incandescence:** emission of optical radiation by the process of thermal radiation.

**incandescent lamp:** lamp in which light is produced by means of an element heated to incandescence by the passage of an electric current.

**indirect lighting:** lighting by means of luminaires having a distribution of luminous intensity such that the fraction of the emitted luminous flux directly reaching the working plane, assumed to be unbounded, is 0 to 10%.

**infrared radiation:** optical radiation for which the wavelengths are longer than those for visible radiation.

**lamp:** source made in order to produce an optical radiation, usually visible.

**LED driver:** a device to power and control a light-emitting diode.

**life cycle:** consecutive and interlinked stages of a product system, from raw material acquisition or generation of natural resources to final disposal.

**light emitting diode (LED):** solid state device embodying a p-n junction, emitting optical radiation when excited by an electric current.

**light trespass:** a situation that occurs when light from a source is emitted into areas where the light is unwanted.
**lighting power density:** a measurement of the amount of electric power required to illuminate an area. Light power density is equal to the electrical power used to produce light in a given area divided by the floor area served by that light; measured in watts per square metre.

**linear fluorescent lamp (LFL):** a straight fluorescent lamp.

**low pressure sodium lamp:** a discharge lamp in which the light is produced by radiation from sodium vapour operating at a partial pressure of 0.1 to 1.5 pascal.

**lumen (lm):** SI unit of luminous flux; luminous flux emitted in unit solid angle by a uniform point source having a luminous intensity of 1 candela.

**luminaire:** apparatus which distributes, filters or transforms the light transmitted from one or more lamps and which includes, except the lamps themselves, all the parts necessary for fixing and protecting the lamps and, where necessary, circuit auxiliaries together with the means for connecting them to the electric supply.

**light output ratio of a luminaire (LOR):** ratio of the total flux of the luminaire, measured under specified practical conditions with its own lamps and equipment, to the sum of the individual luminous fluxes of the same lamps when operated outside the luminaire with the same equipment, under specified conditions.

**luminance:** the luminous flux emitted in a given direction divided by the product of the projected area of the source element perpendicular to the direction and the solid angle containing that direction; unit: cd.m⁻².

**luminous efficacy of a source:** quotient of the luminous flux emitted by the power consumed by the source; unit: lm/W.

**luminous environment:** lighting considered in relation to its physiological and psychological effects.

**luminous flux:** quantity derived from radiant flux by evaluating the radiation according to its action upon the CIE standard photometric observer; unit: lm.

**luminous intensity:** the quotient of the luminous flux leaving the source and propagated in the element of solid angle containing the given direction by the solid angle; unit: cd.

**lux (lx):** SI unit of illuminance; illuminance produced on a surface of area 1 square meter by a luminous flux of 1 lumen uniformly distributed over that surface.

**megalumen-hour (Mlmh):** 1x 10⁶ lumen-hours; a quantity of light.

**mercury vapour lamp:** a type of high-intensity discharge lamp that contains mercury vapour.

**metal halide lamp:** a high intensity discharge lamp in which the major portion of the light is produced from a mixture of a metallic vapour and the products of the dissociation of halides.

**normalized power density of lighting installation:** lighting power density divided by the mean maintained illuminance on the reference plane; unit: W/(m².100 lx)

**organic light emitting diode (OLED):** a semiconductor device made from an organic compound and which emits light when a current is passed through it.

**overhead glare:** a form of glare caused by excessive brightness directly above the user.

**petalumen-hour (Plmh):** 1x 10¹⁵ lumen-hours; a quantity of light.

**Photobiology:** branch of biology which deals with the effects of optical irradiation on living systems.

**Planckian radiator:** ideal thermal radiator that absorbs completely all incident radiation, whatever
the wavelength, the direction of incidence or the polarization. This radiator has, for any wavelength and any direction, the maximum spectral concentration of radiance for a thermal radiator in thermal equilibrium at a given temperature.

**power factor:** the ratio of total real power in watts to the apparent power (root-mean-square volt amperes).

**primary energy:** the energy embodied in natural resources (eg coal, crude oil, uranium, etc.) prior to undergoing any human-made conversions or transformations.

**quantity of light:** time integral of the luminous flux over a given duration; unit: lumen-hour (lm.h).

**radiation:** emission or transfer of energy in the form of electromagnetic waves with the associated photons.

**reflectance:** ratio of the reflected radiant or luminous flux to the incident flux in the given conditions.

**reflector:** device used to alter the spatial distribution of the luminous flux from a source and depending essentially on the phenomenon of the reflection.

**source-lumen:** lumens emitted by a light source.

**spectrum:** display or specification of the monochromatic components of the radiation considered.

**starter:** a starting device, usually for fluorescent lamps, which provides for the necessary preheating of the electrodes and, in combination with the series impedance of the ballast, causes a surge in the voltage applied to the lamp.

**stroboscopic effect:** apparent change of motion and/or appearance of a moving object when the object is illuminated by a light of varying intensity.

**task lighting:** lighting directed to a specific surface or area that provides illumination for visual tasks.

**tungsten halogen lamp:** gas-filled lamp containing halogens or halogen compounds, the filament being of tungsten.

**ultraviolet radiation:** optical radiation for which the wavelengths are shorter than those for visible radiation.

**utilance (U):** ratio of the luminous flux received by the reference surface to the sum of the individual total fluxes of the luminaries of the installation.

**veiling reflections:** specular reflections that appear on the object viewed and that partially or wholly obscure the details by reducing contrast.

**visual comfort:** subjective condition of visual well-being induced by the visual environment.

**visual comfort probability (VCP):** the rating of a lighting system expressed as a percentage of people who, when viewing from a specified location and in a specified direction, will be expected to find it acceptable in terms of discomfort glare.

**visual performance:** performance of the visual system as measured for instance by the speed and accuracy with which a visual task is performed.

**visual task:** visual elements of the work being done.
16 Abbreviations

<table><tr><td>AADL</td><td>Asociación Argentina de Luminotecnia (Argentine Lighting Association)</td></tr><tr><td>AC</td><td>alternating current</td></tr><tr><td>ACGIH</td><td>American Conference of Governmental Industrial Hygienists</td></tr><tr><td>ADC</td><td>analogue-to-digital converter</td></tr><tr><td>AlInGaP</td><td>aluminium gallium indium phosphide</td></tr><tr><td>ANSI</td><td>American National Standards Institute</td></tr><tr><td>ASHRAE</td><td>American Society of Heating, Refrigeration and Air-Conditioning Engineers</td></tr><tr><td>ASIC</td><td>application-specific integrated circuit</td></tr><tr><td>BEMS</td><td>building and energy management system</td></tr><tr><td>BLH</td><td>blue light hazard</td></tr><tr><td>BMS</td><td>building management system</td></tr><tr><td>BTU</td><td>British thermal unit</td></tr><tr><td>CCM</td><td>continuous-current mode</td></tr><tr><td>CCT</td><td>correlated colour temperature</td></tr><tr><td>CELMA</td><td>Federation of National Manufacturers Associations for Luminaries and</td></tr><tr><td>CEN</td><td>Electrotechnical Components for Luminaries in the European Union</td></tr><tr><td></td><td>Comité Européen de Normalisation (European Committee for Standardization)</td></tr><tr><td>CFL</td><td>compact fluorescent lamp</td></tr><tr><td>CICS</td><td>constant illuminance control strategy</td></tr><tr><td>CIE</td><td>Commission Internationale de l'Eclairage (International Commission on Illumination)</td></tr><tr><td>CO<sub>2</sub></td><td>carbon dioxide</td></tr><tr><td>CRI</td><td>colour rendering index</td></tr><tr><td>DAC</td><td>digital-to-analogue converter</td></tr><tr><td>DALI</td><td>digital addressable lighting interface</td></tr><tr><td>DC</td><td>direct current</td></tr><tr><td>DCM</td><td>discontinuous conduction mode</td></tr><tr><td>DHCS</td><td>daylight harvesting control strategy</td></tr><tr><td>DLP</td><td>digital lighting processing</td></tr><tr><td>EC</td><td>European Commission</td></tr><tr><td>ECBCS</td><td>Energy Conservation in Buildings and Community Systems</td></tr><tr><td>EEI</td><td>energy efficiency index</td></tr><tr><td>EEPROM</td><td>electrically erasable programmable read-only memory</td></tr><tr><td>ELC</td><td>European Lamp Companies Federation</td></tr><tr><td>EMC</td><td>electromagnetic compatibility</td></tr><tr><td>EMI</td><td>electromagnetic interference</td></tr><tr><td>EPBD</td><td>Energy Performance of Buildings Directive (European Union)</td></tr><tr><td>EU</td><td>European Union</td></tr><tr><td>EuP</td><td>energy-using products</td></tr><tr><td>FTP</td><td>functional performance testing</td></tr><tr><td>GaAsP</td><td>gallium arsenic phosphide</td></tr><tr><td>GLS</td><td>general service lamp</td></tr><tr><td>HfN</td><td>hafnium-nitrite</td></tr></table>
<table><tr><td>HID</td><td>high-intensity discharge</td></tr><tr><td>HPS</td><td>high-pressure sodium</td></tr><tr><td>HVAC</td><td>heating, ventilation and air-conditioning</td></tr><tr><td>IAEEL</td><td>International Association for Energy-Efficient Lighting</td></tr><tr><td>IC</td><td>integrated circuit</td></tr><tr><td>ICNIRP</td><td>International Commission on Non-Ionizing Radiation Protection</td></tr><tr><td>IEA</td><td>International Energy Agency</td></tr><tr><td>IEC</td><td>International Electrotechnical Commission</td></tr><tr><td>IECC</td><td>International Energy Conservation Code</td></tr><tr><td>IEEE</td><td>Institute of Electrical and Electronics Engineers</td></tr><tr><td>IES</td><td>Illuminating Engineering Society</td></tr><tr><td>IESNA</td><td>Illuminating Engineering Society of North America</td></tr><tr><td>IP</td><td>internet protocol</td></tr><tr><td>ipRGC</td><td>intrinsically photoreceptive retinal ganglion cells</td></tr><tr><td>IR</td><td>infrared</td></tr><tr><td>ISO</td><td>International Organization for Standardization</td></tr><tr><td>LCA</td><td>Life Cycle Analysis</td></tr><tr><td>LCC</td><td>Life Cycle Cost</td></tr><tr><td>LCCA</td><td>Life Cycle Cost Analysis</td></tr><tr><td>LCD</td><td>liquid crystal display</td></tr><tr><td>LEP</td><td>light emitting polymer</td></tr><tr><td>LED</td><td>light emitting diode</td></tr><tr><td>LEED</td><td>Leadership in Energy and Environmental Design (United States)</td></tr><tr><td>LENI</td><td>Lighting Energy Numeric Indicator</td></tr><tr><td>LFL</td><td>linear fluorescent lamp</td></tr><tr><td>LMS</td><td>lighting management system</td></tr><tr><td>LOR</td><td>luminaire output ratio</td></tr><tr><td>LPD</td><td>lighting power density</td></tr><tr><td>LPS</td><td>linear power supply</td></tr><tr><td>MEEUP</td><td>methodology study for ecodesign of the energy-using products</td></tr><tr><td>MF</td><td>maintenance factor</td></tr><tr><td>MHL</td><td>metal-halide lamp</td></tr><tr><td>Mlmh</td><td>megalumen-hours</td></tr><tr><td>Mtoe</td><td>million tonnes of oil equivalent</td></tr><tr><td>NIF</td><td>non-image forming</td></tr><tr><td>NPD</td><td>normalized power density</td></tr><tr><td>OECD</td><td>Organisation for Economic Co-operation and Development</td></tr><tr><td>OLED</td><td>organic light emitting diode</td></tr><tr><td>PCA</td><td>polycrystalline sintered alumina</td></tr><tr><td>PCB</td><td>printed circuit board</td></tr><tr><td>PF</td><td>power factor</td></tr><tr><td>PLC</td><td>power line communication</td></tr><tr><td>Plmh</td><td>petalumen-hours</td></tr><tr><td>POCS</td><td>predicted occupancy control strategy</td></tr><tr><td>PWM</td><td>pulse width modulation</td></tr><tr><td>RAM</td><td>random-access memory</td></tr><tr><td>RFI</td><td>radio frequency interference</td></tr><tr><td>ROCS</td><td>real occupancy control strategy</td></tr><tr><td>RoHS</td><td>restriction of hazardous substances</td></tr><tr><td>ROM</td><td>read-only memory</td></tr></table>
<table><tr><td>RUF</td><td>room utilization factor</td></tr><tr><td>RVP</td><td>relative visual performance</td></tr><tr><td>SCR</td><td>silicon-controlled rectifiers</td></tr><tr><td>SEPIC</td><td>single-ended primary inductance converter</td></tr><tr><td>SMPC</td><td>switched mode power converter</td></tr><tr><td>SMPS</td><td>switched mode power supply</td></tr><tr><td>SPD</td><td>spectral power distribution</td></tr><tr><td>THD<sub>i</sub></td><td>total harmonic distortion</td></tr><tr><td>TLV</td><td>threshold limit value</td></tr><tr><td>UGR</td><td>unified glare rating</td></tr><tr><td>UK</td><td>United Kingdom</td></tr><tr><td>US</td><td>United States</td></tr><tr><td>USART</td><td>universal serial asynchronous receiver-transmitter</td></tr><tr><td>UV</td><td>ultraviolet</td></tr><tr><td>VAV</td><td>variable air volume</td></tr><tr><td>VCP</td><td>visual comfort probability</td></tr><tr><td>VDSF</td><td>ventilated double skin facades</td></tr><tr><td>VDT</td><td>visual display terminal</td></tr><tr><td>WEEE</td><td>Waste Electrical and Electronic Equipment</td></tr></table>
Appendix A: Summary of lighting recommendations

<table><thead><tr><th colspan="3">CHINA - GB 50034-2004 Standard for lighting design of buildings</th></tr><tr><th>NEEDS &amp; EXPECTATIONS<br>Human, societal, environmental</th><th>PARAMETERS</th><th>REQUIREMENTS</th></tr><tr><th>A. INDIVIDUAL NEEDS</th><th></th><th>Level 1</th><th>Level 2</th></tr></thead><tbody><tr><td rowspan="10">VISUAL PERFORMANCE</td><td>Illuminance (horizontal)<br>Task area</td><td>500 lx</td><td>300 lx</td></tr><tr><td>Drawing</td><td>500 lx</td><td></td></tr><tr><td>Illuminance (horizontal), computer</td><td></td><td></td></tr><tr><td>Meeting room</td><td>300 lx</td><td></td></tr><tr><td>Reception</td><td>300 lx</td><td></td></tr><tr><td>Corridors</td><td>100 lx</td><td>50 lx</td></tr><tr><td>Archives</td><td>200 lx</td><td></td></tr><tr><td>Illuminances of immediate surroundings</td><td>300 lx</td><td>200 lx</td></tr><tr><td>Illuminance (vert) on screens</td><td></td><td></td></tr><tr><td rowspan="11">VISUAL COMFORT</td><td>Luminance ratio on task area</td><td colspan="2">1:3 near work place</td></tr><tr><td>Ceiling luminance</td><td colspan="2">Minimum shielding angle:<br>10°→ 1-20 kcd/ m²<br>15°→ 20-50 kcd/ m²<br>20°→ 50-500 kcd/ m²<br>30°→ ≥ 500 kcd/ m²</td></tr><tr><td>Maximum luminances from luminaries overhead</td><td colspan="2">Maximum required luminances<br>1000 cd/ m²</td></tr><tr><td>Wall luminances</td><td colspan="2">Less than 10:3:1</td></tr><tr><td>Maximum luminance from window</td><td colspan="2"></td></tr><tr><td>Surface reflectance</td><td colspan="2">ρceiling 0.6-0.9, ρwalls 0.3-0.8<br>ρworking planes 0.2-0.6, ρfloor 0.1-0.5</td></tr><tr><td>Flicker-Free</td><td colspan="2"></td></tr><tr><td>Uniformity task</td><td colspan="2">>0.7</td></tr><tr><td>Contrast rendering factor</td><td colspan="2">>0.5</td></tr><tr><td>Uniformity surroundings</td><td colspan="2">>0.5</td></tr><tr><td>Discomfort glare</td><td colspan="2">UGR ≤ 19</td></tr><tr><td rowspan="2">COLOUR APPEARANCE</td><td>Reflected glare</td><td colspan="2">To prevent and reduce glare and veiling reflections: Do not install luminaries in areas which can appear interferences. Don't use material which increase glare. Set maximum value for the illuminance.</td></tr><tr><td>Veiling reflections</td><td colspan="2"></td></tr><tr><td rowspan="7">WELL-BEING</td><td>Colour rendering of light (CRI)</td><td colspan="2">>80</td></tr><tr><td>Colour temperature of light CCT</td><td colspan="2">3300 K &lt; CCT &lt; 5300 K</td></tr><tr><td>Use of saturated colours</td><td colspan="2"></td></tr><tr><td>Colour Variations</td><td colspan="2"></td></tr><tr><td>Contact to the outside</td><td colspan="2">Use daylight as much as possible</td></tr><tr><td>Light modelling</td><td colspan="2"></td></tr><tr><td>Daylight consideration</td><td colspan="2">Use of daylight allows dimming and switching on/off lamps.<br>Considerations about daylight system.</td></tr><tr><td rowspan="4">NON VISUAL EFFECTS</td><td>Lighting design</td><td colspan="2">Choose the CCT of lamps according to the characteristics of the place.</td></tr><tr><td>Aesthetics of space</td><td colspan="2"></td></tr><tr><td>Aesthetics of lighting equipment</td><td colspan="2"></td></tr><tr><td>Spectral distribution</td><td colspan="2"></td></tr><tr><td></td><td>Daily doses</td><td colspan="2"></td></tr><tr><td></td><td>Frequency</td><td colspan="2"></td></tr></tbody></table>
<table><tbody><tr><td></td><td>UV amount</td><td></td></tr><tr><td></td><td>IR amount</td><td></td></tr><tr><td colspan="3"><strong>B. SOCIETY NEEDS</strong></td></tr><tr><td></td><td>Cost, budget</td><td></td></tr><tr><td></td><td>Productivity<br>Reduction of complaints<br>More individual control</td><td>If it is possible, use automatic lighting control system based on availability of daylight.</td></tr><tr><td></td><td>Maintenance</td><td>All the repairs and safety checks should be performed by professionals.<br>A system should be set up for cleaning the luminaries and the lamps according to the standard requirements. All the cleaning work should follow this system.<br>The used luminaries should be changed by new ones when they meet their expected lifetime.<br>When replacing the old luminaries with new ones, make sure that they have similar light output as the original design.<br>Periodic checkup and tests should be performed for the luminaries.</td></tr><tr><td></td><td>Lamp type</td><td>Fluorescent lamp<br>Should not use incandescent lamps except for reasons described in this standard e.g. dimming, immediate open, often turn on/off, emergency lamps. In this case, the power should be less than 100 W.<br>Considerations according to the environmental particularity (humidity, high temperature...)</td></tr><tr><td></td><td>Security</td><td>It is better to use battery for emergency sign.<br>The battery should be located beside the place for repair.</td></tr><tr><td></td><td>Feeling of safety</td><td>The illuminance of emergency lighting should not be lower than 5% of normal lighting.<br>The illuminance of escape lighting > 0.5 lx</td></tr><tr><td></td><td>Lighting Management</td><td>Occupancy sensors<br>In some buildings according to the requirement, light should automatically control itself, e.g. elevator corridors should dim light automatically during evening.</td></tr><tr><td colspan="3"><strong>C. ENVIRONMENTAL NEEDS</strong></td></tr><tr><td></td><td>Use of daylight</td><td>Use daylight as much as possible. Refer to the standard GB/T50033 about daylighting.</td></tr><tr><td></td><td>Efficiency for peak load</td><td>Efficient luminaries should be chosen.<br>Efficiency for fluorescent ceiling luminaries: 60%</td></tr><tr><td></td><td>Lighting control</td><td>If possible, automatic lighting control system based on availability of daylight.<br>Paragraph about lighting control in public buildings, gymnasium, cinema, hotel and residential areas.<br>Lighting for corridors, stairs and halls should be controlled in one place and automatically.<br>Controls in groups according to daylight and the usage of buildings.<br>Others considerations.</td></tr><tr><td></td><td>Mercury / Harmonics</td><td>Do not use mercury vapor lamps in normal indoor areas.</td></tr><tr><td></td><td>Lamp extinction</td><td>Use of fluorescent lamp, daylight, electronics ballasts.<br>Assessment for energy savings</td></tr><tr><td></td><td>Electrical Power density</td><td>Level 1:18 W/ m²</td></tr></tbody></table>
<table><tr><td></td><td>Level 2: 11 W/m²<br/>Current value & target value for different offices<br/>(Normal office : 11W/m² and 9 W/m²)</td></tr><tr><td>Energy Consumption</td><td>When the amount of used electricity is being<br/>evaluated, "per user" should be used as the unit.<br/>e.g. 45 kW / user.</td></tr></table>

Some points in the Chinese lighting codes:

1. The requirements of electrical power density for office lighting, commercial lighting, hotel lighting, hospital lighting, school lighting and industry lighting are mandatory, while other items are recommended.

2. In the requirements of electrical power density, there are two values for each place, one is the mandatory value at this moment, and the other value is the target value in the future. For example, the mandatory value for office light level 1(500lx) is 18 W/m², and the target value is 15 W/m². The mandatory value for office light level 2(300lx) is 11 W/m², and the target value is 9 W/m².

3. In office lighting with VDTs, the luminance on the surface of luminaire at angles of > 65° to perpendicular bisector is limited. For screen with good quality (class I, II), the value should be lower than 1000 cd/m². For screen with bad quality (class III), the value should be lower than 200 cd/m².

4. The lighting codes have following proposed items for daylighting:

- The automatic lighting control system based on the change of outdoor's lighting condition, if possible.

- Daylighting should be used in indoor lighting by some light tube or reflected installation, if possible.

- The solar energy should be used, if possible.
JAPAN - The Japanese code JIES-008(1999)

<table><thead><tr><th>NEEDS &<br>EXPECTATIONS<br>(Human, societal,<br>environmental)</th><th>PARAMETERS</th><th>REQUIREMENTS</th></tr></thead><tbody><tr><td colspan="3"><strong>A. INDIVIDUAL NEEDS</strong></td></tr><tr><td rowspan="6">VISUAL<br>PERFORMANCE</td><td>Illuminance (horizontal)<br>Task area</td><td>750 lx &lt; x &lt; 1500 lx</td></tr><tr><td>Illuminance vertical on task area</td><td>&gt; 150 lx</td></tr><tr><td>Illuminance (horizontal), computer<br>drawing</td><td>500 lx<br>&gt;750 lx</td></tr><tr><td>Illuminances of immediate<br>surroundings</td><td>200 lx</td></tr><tr><td>Illuminance (vertical) on screens</td><td></td></tr><tr><td>Luminance ratio on task area</td><td>1:5</td></tr><tr><td rowspan="10">VISUAL COMFORT</td><td>Ceiling luminance</td><td></td></tr><tr><td>Maximum luminances from luminaries<br>overhead</td><td></td></tr><tr><td>Maximum wall luminances</td><td></td></tr><tr><td>Maximum luminance from window</td><td></td></tr><tr><td>Surface reflectance</td><td></td></tr><tr><td>Flicker-free</td><td></td></tr><tr><td>Uniformity task</td><td>&gt; 0.6</td></tr><tr><td>Uniformity surroundings</td><td></td></tr><tr><td>Discomfort glare</td><td>range of quality class of discomfort glare D2,<br>D3</td></tr><tr><td>discomfort glare for VDT</td><td>D1, D2</td></tr><tr><td>Reflected glare<br>Veiling reflections</td><td>luminance limitation of V glare classification<br>luminaire V2 &lt; 200 cd/m²<br>V3 &lt; 2000cd/m²</td></tr><tr><td>Luminaires</td><td>G2, V2 (block horizontal line of sight to the<br>lamp) limit glare</td></tr><tr><td rowspan="4">COLOUR<br>APPEARANCE</td><td>Colour rendering of light CRI</td><td>80 &lt; CRI &lt; 90</td></tr><tr><td>Colour temperature of light CCT</td><td>CCT &gt; 3300 K</td></tr><tr><td>Use of saturated colours</td><td></td></tr><tr><td>Colour variations</td><td></td></tr><tr><td rowspan="8">WELL-BEING</td><td>Contact to the outside</td><td></td></tr><tr><td>Light modelling</td><td></td></tr><tr><td>Directional lighting</td><td></td></tr><tr><td>Biophilia hypothesis</td><td></td></tr><tr><td>Aesthetics of space</td><td></td></tr><tr><td>Aesthetics of lighting equipment</td><td></td></tr><tr><td>Daylight control</td><td>blinds</td></tr><tr><td>Spectral distribution</td><td></td></tr><tr><td rowspan="6">NON VISUAL<br>EFFECTS</td><td>Daylight factor</td><td>1.5% &lt; x &lt; 2%</td></tr><tr><td>Daily doses</td><td></td></tr><tr><td>Frequency</td><td></td></tr><tr><td>UV amount</td><td></td></tr><tr><td>IR amount</td><td></td></tr><tr><td colspan="3"><strong>B. SOCIETY NEEDS</strong></td></tr><tr><td></td><td>Cost, budget</td><td></td></tr><tr><td></td><td>Productivity, Reduction of complaints<br>More individual control</td><td></td></tr><tr><td></td><td>Maintenance</td><td></td></tr><tr><td></td><td>Security</td><td></td></tr><tr><td></td><td>Feeling of safety</td><td></td></tr></tbody></table>
C. ENVIRONMENTAL NEEDS

<table><tr><td>Efficiency for peak load</td><td></td></tr><tr><td>Luminous efficacy</td><td></td></tr><tr><td>Mercury / Harmonics</td><td></td></tr><tr><td>Reduction of resources</td><td></td></tr><tr><td>Lamp extinction</td><td></td></tr><tr><td>Electrical Power density</td><td></td></tr><tr><td>Energy Consumption</td><td></td></tr></table>
European code EN 12464-1; offices

<table><thead><tr><th>NEEDS &<br>EXPECTATIONS<br>(Human, societal,<br>environmental)</th><th>PARAMETERS</th><th>REQUIREMENTS</th></tr></thead><tbody><tr><td colspan="3"><strong>A. INDIVIDUAL NEEDS</strong></td></tr><tr><td rowspan="6">VISUAL<br>PERFORMANCE</td><td>Illuminance (horizontal) task area</td><td>&gt; 500 lx</td></tr><tr><td>Drawing</td><td>&gt; 750 lx</td></tr><tr><td>Illuminance (horizontal), computer</td><td>&gt; 500 lx</td></tr><tr><td>Illuminances of immediate<br>surroundings</td><td>Ambient lighting &gt; 300 lx</td></tr><tr><td>Archives</td><td>200 lx</td></tr><tr><td>Illuminance (vertical) on screens</td><td>&lt; 200 lx</td></tr><tr><td rowspan="10">VISUAL COMFORT</td><td>Luminance ratio on task area</td><td>1:3 near work place<br>1:10 for other surfaces</td></tr><tr><td>Shielding</td><td>there are minimum shielding angles according to<br>the light level</td></tr><tr><td>Ceiling luminance</td><td></td></tr><tr><td>Maximum luminances from luminaries<br>overhead</td><td>Luminances of room surfaces, 40:1.<br>Angles from luminaries and "high value"</td></tr><tr><td>Wall luminances</td><td>Less than 10:3:1</td></tr><tr><td>Maximum luminance from window</td><td></td></tr><tr><td>Surface reflectance</td><td>ρceiling: 0.6-0.9 ρwalls: 0.3-0.8<br>ρworking planes: 0.2-0.6 ρfloor: 0.1-0.5</td></tr><tr><td>Flicker-free</td><td>avoid flicker & stroboscopic effects by lighting<br>system</td></tr><tr><td>Uniformity task</td><td>&gt; 0.7</td></tr><tr><td>Uniformity surroundings</td><td>&gt; 0.5</td></tr><tr><td>Discomfort glare</td><td>UGR ≤ 19</td></tr><tr><td>Reflected glare<br>Veiling reflections</td><td>must be prevented or reduced</td></tr><tr><td rowspan="3">COLOUR<br>APPEARANCE</td><td>Colour rendering of light CRI</td><td>&gt; 80</td></tr><tr><td>Colour temperature of light CCT</td><td>3000 K &lt; CCT &lt; 5000 K</td></tr><tr><td>Use of saturated colours</td><td></td></tr><tr><td rowspan="10">WELL-BEING</td><td>Colour variations</td><td></td></tr><tr><td>Contact to the outside</td><td>Window next to work place, with good shading</td></tr><tr><td>Daylight factor</td><td></td></tr><tr><td>Daylight consideration</td><td>use of available daylight</td></tr><tr><td>Light modelling</td><td>not too directional, not too diffuse</td></tr><tr><td>Directional lighting</td><td>on visual task</td></tr><tr><td>Biophilia hypothesis</td><td></td></tr><tr><td>Aesthetics of space</td><td></td></tr><tr><td>Aesthetics of lighting equipment</td><td></td></tr><tr><td rowspan="4">NON VISUAL<br>EFFECTS</td><td>Spectral distribution</td><td></td></tr><tr><td>Daily doses</td><td></td></tr><tr><td>Frequency</td><td></td></tr><tr><td>UV amount / IR amount</td><td></td></tr><tr><td colspan="3"><strong>B. SOCIETY NEEDS</strong></td></tr><tr><td></td><td>Cost, budget</td><td></td></tr><tr><td></td><td>Productivity / Reduction of complaints</td><td>More individual control</td></tr><tr><td></td><td>Maintenance</td><td>Maintenance factor must be calculated,<br>a maintenance scheduled must be prepared</td></tr><tr><td></td><td>Security</td><td>Safety level (min 1 lx emergency lighting), EN<br>1834</td></tr><tr><td></td><td>Feeling of safety</td><td></td></tr><tr><td></td><td>Lighting management</td><td></td></tr></tbody></table>
C. ENVIRONMENTAL NEEDS

<table><tr><td>Lighting control</td><td>automatic or manual switching and/or dimming</td></tr><tr><td>Efficiency for peak load</td><td></td></tr><tr><td>Luminous efficacy</td><td></td></tr><tr><td>Mercury / Harmonics</td><td></td></tr><tr><td>Reduction of resources / Lamp extinction</td><td></td></tr><tr><td>Electrical power density</td><td></td></tr><tr><td>Energy Consumption</td><td>no waste of energy, reduce energy to the max with appropriate lighting technology</td></tr></table>

1) in the definitions it is said that lighting is to ensure:

- -visual comfort

- -visual performance

- -safety

2) In office lighting with VDTs, the luminance on the surface of luminaire at the angle of > 65° to perpendicular bisector is limited. For screen with good quality (class I, II), the value should be lower than 1000 cd/m². For screen with low quality (class III), the value should be lower than 200 cd/m².
BRAZIL - CIE S 008/E-2001

<table><thead><tr><th>NEEDS &<br>EXPECTATIONS<br>(Human, societal,<br>environmental)</th><th>PARAMETERS</th><th>REQUIREMENTS</th></tr></thead><tbody><tr><td colspan="3"><strong>A. INDIVIDUAL NEEDS</strong></td></tr><tr><td rowspan="7">VISUAL<br>PERFORMANCE</td><td>Illuminance (horizontal)</td><td>500 lx</td></tr><tr><td>Task area, conference room</td><td></td></tr><tr><td>Illuminance (horizontal), computer</td><td></td></tr><tr><td>Illuminances of immediate surroundings</td><td>300 lx</td></tr><tr><td>Drawing</td><td>750 lx</td></tr><tr><td>Archives</td><td>200 lx</td></tr><tr><td>Illuminance (vertical) on screens</td><td></td></tr><tr><td rowspan="7">VISUAL COMFORT</td><td>Luminance ratio on task area</td><td></td></tr><tr><td>Ceiling luminance</td><td></td></tr><tr><td>Maximum luminances from luminaries overhead</td><td>&lt; 1000 cd/m²</td></tr><tr><td>Maximum wall luminances</td><td></td></tr><tr><td>Maximum luminance from window</td><td></td></tr><tr><td>Surface reflectance</td><td>ρceiling: 0.6-0.9<br>ρwalls: 0.3-0.8<br>ρworking planes: 0.3-0.6<br>ρfloor: 0.1-0.5</td></tr><tr><td>Flicker-free</td><td>use DC electrical supply or operating lamps at high frequency (30 kHz)</td></tr><tr><td rowspan="5">COLOUR<br>APPEARANCE</td><td>Uniformity task</td><td>0.7</td></tr><tr><td>Uniformity surroundings</td><td>0.5</td></tr><tr><td>Discomfort glare</td><td>UGR &lt; 19</td></tr><tr><td>Reflected glare / Veiling reflections</td><td>must be prevented or reduced</td></tr><tr><td>Colour rendering of light CRI</td><td>&gt;80</td></tr><tr><td rowspan="5">WELL-BEING</td><td>Colour temperature of light CCT</td><td></td></tr><tr><td>Use of saturated colours</td><td></td></tr><tr><td>Colour variations</td><td></td></tr><tr><td>Daylight factor</td><td>&gt; 1% within 3m from the window</td></tr><tr><td>Contact to the outside</td><td>window is required to provide part or all lighting</td></tr><tr><td rowspan="5">NON VISUAL<br>EFFECTS</td><td>Light modelling</td><td>not too directional<br>not too diffuse</td></tr><tr><td>Directional lighting</td><td></td></tr><tr><td>Biophilia hypothesis</td><td></td></tr><tr><td>Aesthetics of space</td><td></td></tr><tr><td>Aesthetics of lighting equipment</td><td></td></tr><tr><td></td><td>Spectral distribution</td><td></td></tr><tr><td></td><td>Daily doses</td><td></td></tr><tr><td></td><td>Frequency</td><td></td></tr><tr><td></td><td>UV amount</td><td></td></tr><tr><td></td><td>IR amount</td><td></td></tr><tr><td colspan="3"><strong>B. SOCIETY NEEDS</strong></td></tr><tr><td></td><td>Cost, budget</td><td></td></tr><tr><td></td><td>Productivity, Reduction of complaints</td><td></td></tr><tr><td></td><td>More individual control</td><td></td></tr><tr><td></td><td>Maintenance factor</td><td>&lt; 0.7</td></tr><tr><td></td><td>Security</td><td></td></tr><tr><td></td><td>Feeling of safety</td><td></td></tr><tr><td></td><td>Lighting Management</td><td></td></tr><tr><td colspan="3"><strong>C. ENVIRONMENTAL NEEDS</strong></td></tr></tbody></table>
<table><tr><td>Efficiency for peak load</td><td></td></tr><tr><td>Luminous efficacy</td><td></td></tr><tr><td>Mercury / Harmonics</td><td></td></tr><tr><td>Reduction of resources</td><td></td></tr><tr><td>Lamp extinction</td><td></td></tr><tr><td>Electrical power density</td><td></td></tr><tr><td>Energy consumption</td><td></td></tr></table>

1) In the definitions it is said that lighting is to ensure:

- visual comfort

- visual performance

- safety

2) In the office lighting with VDT, the luminance on the surface of luminaire at the angle of > 65° to perpendicular bisector is limited. For screen with good quality (class I, II), the value should be lower than 1000 cd/m². For screen with low quality (class III), the value should be lower than 200 cd/m².
RUSSIA - SNiP 23-05-95 Daylight and Artificial Lighting

<table><thead><tr><th>NEEDS &<br>EXPECTATIONS<br>(Human, societal,<br>environmental)</th><th>PARAMETERS</th><th>REQUIREMENTS</th></tr></thead><tbody><tr><td colspan="3"><strong>A. INDIVIDUAL NEEDS</strong></td></tr><tr><td rowspan="8">VISUAL PERFORMANCE</td><td>Illuminance (horizontal) task area</td><td>With general lighting 300 lx<br>With supplemented lighting: supplementary 400lx &amp; general 200lx</td></tr><tr><td>Drawing</td><td>With general lighting 500 lx<br>With supplemented lighting: supplementary 600lx &amp; general 400 lx</td></tr><tr><td>Illuminance (horizontal), computer</td><td>With general lighting 400 lx<br>With supplemented lighting: supplementary 500lx &amp; general 300 lx</td></tr><tr><td>Conference room</td><td>300 lx</td></tr><tr><td>Reception, lounge, lobbies</td><td>150 lx</td></tr><tr><td>Archives</td><td>With supplemented lighting 75 lx</td></tr><tr><td>Corridors</td><td>main corridors 75 lx<br>other corridors 50lx</td></tr><tr><td>Illuminance (vertical) on screens</td><td>200 lx</td></tr><tr><td rowspan="10">VISUAL COMFORT</td><td>Maximum luminances from<br>luminaries overhead</td><td>Maximum permissible luminance of the work plane are given according to area of work surface: ≤ 500 cd/ m² for area ≥ 0,1 m²</td></tr><tr><td>Wall luminances</td><td></td></tr><tr><td>Luminaire distribution</td><td></td></tr><tr><td>Maximum luminance from window</td><td></td></tr><tr><td>Optimum size range for task detail</td><td></td></tr><tr><td>Surface reflectance</td><td>ρceiling: 0.7-0.8<br>ρwalls: 0.4-0.5<br>ρworking planes: 0.25-0.4<br>ρfurniture: 0.25-0.4<br>ρfloor: 0.25-0.4</td></tr><tr><td>Flicker-free</td><td>In rooms where a stroboscopic effect can occur, adjacent lamps must be connected to three phases of the supply voltage or supplied with electronic ballasts.</td></tr><tr><td>Uniformity task</td><td>Uniformity ratio (maximum illuminance to minimum)<br>Fluorescent lamp ≤ 1,3<br>Other light sources ≤ 1,5<br>Over task area ≤ 1,5 or 2</td></tr><tr><td>Contrast rendering factor</td><td></td></tr><tr><td>Discomfort glare</td><td></td></tr><tr><td>Reflected glare<br>Veiling reflections</td><td>Supplementary lighting: luminaires with opaque reflectors, luminous element not in the field of vision of workers.</td></tr><tr><td rowspan="4">COLOUR APPEARANCE</td><td>Color rendering of light CRI</td><td>CRI = 55 (offices, work rooms, designing and drafting rooms)<br>CRI = 85 (artistic offices, service offices)</td></tr><tr><td>Color temperature of light CCT</td><td>3500 K-5000 K</td></tr><tr><td>Use of saturated colors</td><td></td></tr><tr><td>Color variations</td><td></td></tr><tr><td rowspan="2">WELL-BEING</td><td>Contact to the outside</td><td>Rooms without daylight are permitted only in specific ones (example: located in basement floors of buildings).</td></tr><tr><td>Psychological effects</td><td></td></tr></tbody></table>
<table><tbody><tr><td></td><td>Light modeling</td><td>Supplementary lighting is permitted to achieve the optimum spatial planning arrangements.</td></tr><tr><td></td><td>Daylight consideration</td><td>Daylight is divided into side, top and combination (side & top) lighting. Consideration about the calculation of the daylight factor according to the visual task categories and the type of room.</td></tr><tr><td></td><td>Daylight factor</td><td>Daylighting with side lighting:<br>DF(office)= 1%<br>DF(Design office)= 1.5%<br>DF(conference hall)=0.7%<br>DF(computer room)=1.2%<br>Combined daylight-artificial lighting with side lighting:<br>DF(office)= 0.6%<br>DF(Design office)= 0.9%<br>DF(conference hall)=0.4%<br>DF(computer room)=0.7%</td></tr><tr><td rowspan="4">NON VISUAL EFFECTS</td><td>Spectral distribution</td><td></td></tr><tr><td>Daily doses</td><td></td></tr><tr><td>Frequency</td><td></td></tr><tr><td>UV amount</td><td></td></tr><tr><td></td><td>IR amount</td><td></td></tr><tr><td colspan="3"><b>B. SOCIETY NEEDS</b></td></tr><tr><td></td><td>Cost, Budget</td><td></td></tr><tr><td></td><td>Productivity<br>Reduction of complaints<br>More individual control</td><td>Increase the recommended illuminance in rooms where more than 50% of workers are older than 40 years.</td></tr><tr><td></td><td>Maintenance</td><td></td></tr><tr><td></td><td>Lamp type</td><td>Fluorescent lamp, white color, Metal halide lamp<br>Discharge lamps & Incandescent lamps</td></tr><tr><td></td><td>Security</td><td>Emergency lighting consists of safety and evacuation lighting.<br>Evacuation lighting shall provide illumination on the floor of main passages and on stair steps.<br>Luminaires for safety lighting may be used for evacuation lighting.<br>Lighting device for emergency lighting may be used with the normal lighting system or normally off (switched on automatically)</td></tr><tr><td rowspan="2">emergency lighting</td><td>Feeling of safety</td><td>Minimum illuminance for evacuation lighting :<br>rooms 0.5 lx / Outdoors: 0.2 lx<br>Uniformity of evacuation lighting ≤ 40:1<br>(ratio of maximum to minimum illuminance on the centerline of evacuation passages)<br>Minimum illuminance for safety lighting :<br>0.5 lx<br>At a level of 0.5m from the ground.</td></tr><tr><td>Lighting Management</td><td></td></tr><tr><td colspan="3"><b>C. ENVIRONMENTAL NEEDS</b></td></tr><tr><td></td><td>Use of daylight</td><td>Use of daylight: with top lighting, with side lighting, with combined top-side lighting.<br>Use of combination of daylight-artificial lighting.</td></tr><tr><td></td><td>Efficiency for peak load</td><td>Use of efficient discharge lamps.</td></tr></tbody></table>
<table><tr><td>Lighting control</td><td>Supplementary lighting shall be equipped with dimming.</td></tr><tr><td>Luminous efficacy</td><td>Luminance efficacy ≥ 55 lm/W<br>Fluorescent lamp: Ra≥ 80 → >65 lm/W<br>Ra ≥ 60 → > 75 lm/W<br>Metal halide lamp:<br>Ra ≥ 80 → >75 lm/W<br>Ra ≥ 60 → > 90 lm/W</td></tr><tr><td>Mercury / Harmonics</td><td></td></tr><tr><td>Reduction of resources</td><td></td></tr><tr><td>Lamp extinction</td><td></td></tr><tr><td>Electrical power density</td><td>Maximum allowed power density (W/m²) according to the illuminance on work surface and room index (Kr)</td></tr><tr><td>Energy consumption</td><td></td></tr></table>
AUSTRALIA – AS 1680.1-2006, AS 1680.2.2-1994, AS 1680.2.0-1990

<table><thead><tr><th>NEEDS &<br>EXPECTATIONS<br>(Human, societal,<br>environmental)</th><th>PARAMETERS</th><th>REQUIREMENTS</th></tr></thead><tbody><tr><td colspan="3"><strong>A. INDIVIDUAL NEEDS</strong></td></tr><tr><td rowspan="10">VISUAL PERFORMANCE</td><td>Illuminance (horizontal) task area</td><td>320 lx</td></tr><tr><td>Drawing</td><td>600 lx</td></tr><tr><td>Illuminance (horizontal), computer</td><td>320 lx</td></tr><tr><td>Conference room</td><td>240 lx</td></tr><tr><td>Reception, lounge, lobbies</td><td>160 lx</td></tr><tr><td>Visual task near threshold</td><td></td></tr><tr><td>Illuminances of immediate surroundings</td><td>Not less than the maintained illuminance recommended for the task.<br>Not less than 240 lx for combined system (local&general lighting) or task illuminances&gt;600 lx</td></tr><tr><td>Corridors</td><td>40 lx</td></tr><tr><td>Illuminance (vertical) on screens</td><td>Good, simple: 240 lx<br>Average detail: 320 lx<br>Poor, fine detail: 600 lx</td></tr><tr><td>Luminance ratio on task area</td><td>2:1 between task and background<br>&lt;3:1</td></tr><tr><td rowspan="10">VISUAL COMFORT</td><td>Visual comfort probability</td><td></td></tr><tr><td>Ceiling luminance</td><td>With luminous ceiling, average &lt; 0.5 kcd/m²<br>For indirect lighting systems:<br>Average luminance &lt; 0.5 kcd/m²<br>Max luminance &lt;1.5 kcd/m²</td></tr><tr><td>Maximum luminances from luminaries overhead</td><td>Upward light-output ratio at least 0, 3.<br>55°→ 6 kcd/m²<br>65°→ 3 kcd/m²<br>75°→ 2 kcd/m²<br>85°→ 2 kcd/m²</td></tr><tr><td>Wall luminances</td><td>Illuminance for the background/environment: office & computer room: 160lx<br>drafting office: 240 lx</td></tr><tr><td>Luminaire distribution</td><td>Maximum 3:1</td></tr><tr><td>Maximum luminance from window</td><td></td></tr><tr><td>Surface reflectance</td><td>ρceiling &gt; 0.8<br>ρwalls 0.3-0.7<br>ρworking planes 0.2-0.5<br>ρfurniture 0.2-0.5<br>ρfloor &lt;0.4</td></tr><tr><td>Flicker-free</td><td>To avoid flicker and stroboscopic effects by lighting system. For incandescent lamps, oscillations are small; for discharge lamps, oscillations can be more marked. Depend on sensitivity, amplitude</td></tr><tr><td>Uniformity task</td><td>≥ 0.7 (over the task area)</td></tr><tr><td>contrast rendering factor</td><td>Definition. Further details in CIE 19.21.</td></tr><tr><td>Discomfort glare</td><td>UGR ≤ 19</td></tr><tr><td>Reflected glare<br>Veiling reflections</td><td>Luminaires adjustable in position and orientation<br>Fixed or adjustable task lighting<br>Medium-height partition screens (1.5 m to 1.8 m above floor)</td></tr><tr><td>COLOUR APPEARANCE</td><td>Color rendering of light CRI</td><td>80≤ CRI &lt; 90</td></tr></tbody></table>
<table><tbody><tr><td></td><td>Color temperature of light<br>CCT</td><td>Warm &lt;3300 K<br>Intermediate 3300 K ≤ 5300 K</td></tr><tr><td></td><td>Use of saturated colors</td><td>For decorative effect</td></tr><tr><td></td><td>Color variations</td><td>Uniform color appearance<br>Compatible with the light sources</td></tr><tr><td rowspan="10">WELL-BEING</td><td>Contact to the outside</td><td>People prefer to work with daylight</td></tr><tr><td>Ergonomics (modify work environment to correspond to human capabilities and limitations)</td><td>Rearranging of the workstations in order to reduce discomfort glare.</td></tr><tr><td>Psychological effects</td><td>Diffuse reflection from the screen, conspicuous reflections in dark, high-gloss desk tops can give rise to distraction and annoyance. Indirect lighting can result in an unstimulating environment for work.</td></tr><tr><td>Light modeling</td><td>A combination of diffuse and directional light</td></tr><tr><td>Daylight consideration</td><td>Use available daylight. CIE models for lighting design of daylighting systems.</td></tr><tr><td>Daylight factor</td><td></td></tr><tr><td>Directional lighting</td><td>Highly directional lighting provides uneven general illumination, sharp deep shadows and harsh modeling.<br>Luminous ceilings should not be installed in interiors where screens-based task is used unless space has a room index of 2 or less.</td></tr><tr><td>Biophilia hypothesis</td><td></td></tr><tr><td>Lighting design</td><td>Lighting design procedure: flowchart, description of lighting design stages. Establish design objectives (safety, identifying visual tasks, creating appearance and atmosphere) and design constraints (costs, environmental consideration,...) to have a safe and healthy environment, choice of surface finishes, use of daylight.</td></tr><tr><td>Aesthetics of space</td><td>The sense of space and of form can be influenced by appropriate lighting design.<br>No real considerations about aesthetics.</td></tr><tr><td>Aesthetics of lighting equipment</td><td>Unity in lighting equipment: using of luminaires having a related shape or by harmony of layout.<br>Special interior design considerations to integrate the lighting equipment.</td></tr><tr><td rowspan="5">NON VISUAL EFFECTS</td><td>Spectral distribution</td><td></td></tr><tr><td>Daily doses</td><td></td></tr><tr><td>Frequency</td><td></td></tr><tr><td>UV amount</td><td></td></tr><tr><td>IR amount</td><td></td></tr><tr><td colspan="2">B. SOCIETY NEEDS</td><td></td></tr><tr><td></td><td>Budget, cost</td><td>Economic analysis includes costs, depreciation, taxation, inflation, operating costs, and capital.</td></tr><tr><td></td><td>Productivity<br>Reduction of complaints<br>More individual control</td><td>Local lighting for individual control.<br>Flexibility is the prime requirement.</td></tr><tr><td></td><td>Maintenance</td><td>Maintenance of electric and lighting system (to save costs and energy and prolong life of the system).</td></tr><tr><td></td><td>Lamp type</td><td></td></tr><tr><td>Emergency lighting</td><td>Security</td><td>Safety lighting system can be incorporated into any other lighting system. Emergency evacuation lighting system is useful if the normal lighting system is failing.<br>Color for identification and safety. Colored patch</td></tr></tbody></table>
<table><tr><td rowspan="3">Emergency lighting</td><td>Feeling of safety</td><td>To facilitate the recognition of hazards in general and in relation to specific physical tasks. Illuminating safety warning sign and safe pathways within space.</td></tr><tr><td>Lighting management</td><td>Manual methods, automatic control, computer-based control.</td></tr></table>

C. ENVIRONMENTAL

<table><tr><td>Use of daylight</td><td>The electric lighting serves to supplement daylight. Combined electric lighting and daylighting systems.</td></tr><tr><td>Efficiency for peak load</td><td>Energy savings from reduction in electrical load: choice of lamps, control gear, luminaires, arrangement of luminaires, high reflectance finishes.</td></tr><tr><td>Lighting control</td><td>Automatic or manual switching and/or dimming may be used. (Manual switch, remote switches, time switches, PIR motion sensor and photocells). Dimmers can be controlled manually or automatically. Electronic control gear will give superior performance with discharge lamps.</td></tr><tr><td>Luminous efficacy</td><td></td></tr><tr><td>Mercury</td><td></td></tr><tr><td>Reduction of resources</td><td>Use of daylight, energy conservation, control of internal and external heat gains or losses</td></tr><tr><td>Harmonics</td><td></td></tr><tr><td>Lamp extinction</td><td></td></tr><tr><td>Electrical power density</td><td></td></tr><tr><td>Energy Consumption</td><td>Windows and rooflights have a significant impact on the net annual energy consumption. Design and effective management of windows, increasing window areas (find the optimum window area), control of solar gain, new and more efficient fenestration systems can reduce the energy consumption.</td></tr></table>
Nepal - J.B. Gupta, Electrical installation estimation and costing, New Delhi, 1995, 7th edition

<table><thead><tr><th>NEEDS &<br>EXPECTATIONS<br>(Human, societal,<br>environmental)</th><th>PARAMETERS</th><th>REQUIREMENTS</th></tr></thead><tbody><tr><td colspan="3"><strong>A. INDIVIDUAL NEEDS</strong></td></tr><tr><td rowspan="10">VISUAL PERFORMANCE</td><td>Illuminance (horizontal)<br>task area</td><td>General lighting oriented towards the working surface</td></tr><tr><td>Drawing</td><td>Shadowless light</td></tr><tr><td>Illuminance (horizontal),<br>computer</td><td></td></tr><tr><td>Conference room</td><td></td></tr><tr><td>Reception, lounge, lobbies</td><td>100 lx</td></tr><tr><td>Visual task near threshold</td><td></td></tr><tr><td>Illuminances of immediate<br>surroundings</td><td>300 lx</td></tr><tr><td>Corridors</td><td></td></tr><tr><td>Archives</td><td></td></tr><tr><td>Illuminance (vert) on screens</td><td></td></tr><tr><td rowspan="10">VISUAL COMFORT</td><td>Luminance ratio on task area</td><td>&lt; 3:1</td></tr><tr><td>Luminance reflected in the<br>screen<br>(for elevation angles of 65° or<br>more)</td><td></td></tr><tr><td>Visual comfort probability</td><td></td></tr><tr><td>Ceiling luminance</td><td></td></tr><tr><td>Maximum luminances from<br>luminaries overhead</td><td>Large floor area: luminaries mounted close to the ceiling (direct light)</td></tr><tr><td>Wall luminances</td><td></td></tr><tr><td>Luminaire distribution</td><td></td></tr><tr><td>Maximum luminance from<br>window</td><td></td></tr><tr><td>Optimum size range for task<br>detail</td><td></td></tr><tr><td>Surface reflectance</td><td></td></tr></tbody></table>
USA - ANSI/IESNA RP-1-04, American National Standard Practice for Office Lighting

<table><thead><tr><th>NEEDS &<br>EXPECTATIONS<br>(Human, societal,<br>environmental)</th><th>PARAMETERS</th><th>REQUIREMENTS</th></tr></thead><tbody><tr><td colspan="3"><strong>A. INDIVIDUAL NEEDS</strong></td></tr><tr><td rowspan="10">VISUAL PERFORMANCE</td><td>Illuminance (horizontal) task area</td><td>High contrast and simple task 100 lx<br>High contrast and large visual target size 300 lx<br>Low contrast and large visual target size or high contrast and small visual target size 500 lx<br>Low contrast and small target size 1000 lx</td></tr><tr><td>Drawing</td><td>Horizontal 1000 lx<br>Vertical 500 lx</td></tr><tr><td>Illuminance (horizontal), computer</td><td>300 lx<br>vertical 50 lx</td></tr><tr><td>Conference room</td><td>Meeting: horizontal 300lx, vertical 50 lx<br>Video: horizontal 500 lx, vertical 300 lx</td></tr><tr><td>Reception, lounge, lobbies</td><td>Horizontal 100 lx<br>Vertical 30 lx</td></tr><tr><td>Visual task near threshold</td><td>3000 - 10000 lx</td></tr><tr><td>Illuminances of immediate surroundings</td><td></td></tr><tr><td>Corridors</td><td>50 lx</td></tr><tr><td>Archives</td><td></td></tr><tr><td>Illuminance (vert) on screens</td><td></td></tr><tr><td rowspan="10">VISUAL COMFORT</td><td>Luminance ratio on task area</td><td>Between task and immediate surrounding 3:1<br>Between task and remote 1:10</td></tr><tr><td>Luminance reflected in the screen (for elevation angles of 65° or more)</td><td></td></tr><tr><td>Visual comfort probability</td><td>VCP > 70 %<br>Open plan office VCP > 80</td></tr><tr><td>Ceiling luminance</td><td>Without VDT screen:<br>L<sub>ceiling (maximum)</sub> < 10 x L<sub>task</sub><br>With VDT screen:<br>L<sub>ceiling (maximum)</sub> < 850 cd/m<sup>2</sup></td></tr><tr><td>Maximum luminances from luminaries overhead</td><td>Respect angles and intensity limits to prevent from glare<br>55°: 300 cd, 65°: 220 cd, 75°: 135 cd, 85°: 45 cd</td></tr><tr><td>Wall luminances</td><td></td></tr><tr><td>Luminaire distribution</td><td>Ceiling luminance ratio:<br>maximum=8:1, Best= 2:1, good=4:1</td></tr><tr><td>Maximum luminance from window</td><td></td></tr><tr><td>Optimum size range for task detail</td><td>Reading at desk: 10-12 point</td></tr><tr><td>Surface reflectance</td><td>ρ<sub>ceiling</sub> 0.8<br>ρ<sub>walls</sub> 0.5-0.7<br>ρ<sub>floor</sub> 0.2-0.4<br>ρ<sub>furniture</sub> 0.25-0.45<br>ρ<sub>partitions</sub> 0.4-0.7<br>surface specularity must be considered</td></tr></tbody></table>
<figure><img src="image_293.png" /></figure>
# Appendix B: Questionnaire of lighting system control

This questionnaire has been established by the AIE annex 45 in order:

* To identify the needs of the Building user

* To identify the parameters of the lighting control schemes and systems.

This will help the manufacturer or designer to predict the strategies of lighting control.

## Identification

### Building coordinates

<table><tr><td>Building name</td><td></td><td>Number</td><td></td></tr><tr><td>Address (street)</td><td></td><td>ZIP</td><td></td></tr><tr><td>City</td><td></td><td>State</td><td></td></tr><tr><td>Country</td><td></td><td></td><td></td></tr></table>

### Building type

Offices ☐

Hospitals ☐

Educational buildings ☐

Manufacturing factory ☐

Hotels, bars and restaurants ☐

Wholesale and retail service ☐

Sporting areas ☐

Other ☐

### Contact person

Coordinates:

<table><tr><td>Name</td><td></td><td>Number</td><td></td></tr><tr><td>Address (street)</td><td></td><td>ZIP</td><td></td></tr><tr><td>City</td><td></td><td>State</td><td></td></tr><tr><td>Country</td><td></td><td>Fax</td><td></td></tr><tr><td>Telephone</td><td></td><td></td><td></td></tr><tr><td>E-mail</td><td></td><td></td><td></td></tr></table>

Function :

Building energy manager ☐

Building designer (architect, engineering team...) ☐

Building user ☐

Maintenance team ☐

Other ☐
# Lighting design control

## The most important barrier to using lighting control systems is:

<table><tr><td>There are no barriers</td><td></td></tr><tr><td>Uncertain functioning</td><td></td></tr><tr><td>Too expensive</td><td></td></tr><tr><td>No (or not enough) energy saved</td><td></td></tr><tr><td>Not economically justifiable</td><td></td></tr><tr><td>Other (please specify)</td><td></td></tr></table>

## Lighting control is a way to:

(scale 1 to 5, 1 not important, 5 very important)

<table><tr><td>Save energy</td><td></td></tr><tr><td>Perform maintenance on luminaires</td><td></td></tr><tr><td>Adapt the lighting conditions to the task</td><td></td></tr><tr><td>Be informed on the status of the luminaires</td><td></td></tr><tr><td>Improve the image of the building</td><td></td></tr><tr><td>Improve the productivity of employees</td><td></td></tr><tr><td>Improve the well-being of the building users</td><td></td></tr><tr><td>Install (expensive) useless systems</td><td></td></tr><tr><td>Render the building and its environment dynamic</td><td></td></tr><tr><td>Other (please specify)</td><td></td></tr></table>

## Lighting control has to be designed by :

(scale 1 to 5, 1 not important, 5 very important)

<table><tr><td>The architect</td><td></td></tr><tr><td>The building manager</td><td></td></tr><tr><td>The building owner/user</td><td></td></tr><tr><td>The engineering team</td><td></td></tr><tr><td>The lighting manufacturer</td><td></td></tr><tr><td>Other (please describe)</td><td></td></tr></table>

## Lighting control is expensive:

<table><tr><td>Yes</td><td></td></tr><tr><td>Yes, but with a justifiable payback time</td><td></td></tr><tr><td>No</td><td></td></tr><tr><td>No idea</td><td></td></tr><tr><td>It depends on the system</td><td></td></tr></table>
### Lighting control has to be function of:

(scale 1 to 5, 1 not important, 5 very important)

Absence ☐
Presence ☐
Clock control ☐
Colour control ☐
Daylight ☐
Occupant's demand ☐
Other (please describe) ☐

### Lighting control is best a control

(scale 1 to 5, 1 not important, 5 very important)

For the whole building ☐
By building wing/building orientation ☐
By floor ☐
By room ☐
By work zone ☐
By work place ☐
Other (please describe) ☐

### Lighting control shouldn't be only on/off, it should happen in a gradual way (i.e. continuous dimming or dimming in one or more discrete steps)

Yes ☐
No ☐
No idea ☐

### Lighting control has to be flexible and modular :

Yes ☐
No ☐
No idea ☐

### It is important to maintain the lighting system, in order to attain at every moment the desired lighting level

Yes, maintenance should be performed at a regular basis (following a fixed scheme) ☐

Yes, maintenance is important but punctual interventions (lamp changing, ...) will do ☐

No, maintenance is not important ☐

No idea ☐
# Background of the lighting control design questionnaire

## Aims

The aim of this document is to describe the technical background of the questionnaire. Answers in the questionnaire may be very useful to help the lighting control designer to understand the needs of the building user.

## Explanations

The identification of the uses helps the designer to understand the way he has to design the installation : in a basic school, an On/Off system coupled with daylight dimming may satisfy but in certain offices, it could be necessary to go one step further by integrating more advanced techniques.

The identification of the person who answered the questionnaire may be very useful to understand its needs. The building energy manager will be more interested by the energy consumption and the energy savings.

Asking the perception of the people on the barriers of lighting control may give information about the type and quality of lighting control system that can be applied (basic On/Off switching system, advanced daylight dimming system,...).

Identifying the best person for the designing of the lighting control system delivers information on the perception of the building control system.

Choosing an architect as lighting designer may indicate that the correspondent wants to generate an added value to the building as e.g. a dynamic object. Or that he wants the building to have different possible aspects during day time and night time.

Asking about the type of control gives information on the techniques that will be used for the installation of the sensors. i.e. the cabling of a central clock control will not be the same as the one of a local daylight dimming system.

Asking for the size of the zone controlled by a sensor or input device is very important.

Daylight dimming may be very interesting in case of local zoning but it may not be acceptable in case of control by floor or by building wing. A clock control is best used in case of floor control (including, of course, possibility of derogation).

Identifying the way that the flux can be varied, gives information on the way the control by the sensors has to happen : Switching or dimming (step by step or continuous)

The questions may be linked and structured according to the figure below.
<figure><img src="image_294.png" /><figcaption>Figure B-1. Commissioning process.</figcaption></figure>

The question on flexibility and modularity of the lighting system may be considered as information about the future affectations of the building. For some buildings (i.e. rented offices) light structure walls are displaced and spaces are reorganized regularly. A change of the lighting control system than has to be possible and has to be as easy as possible.

The question on maintenance wants to identify whether the correspondent is aware of the need of a regular maintenance scheme in order to assure a desired light level or considers punctual interventions (e.g. changing of broken lamps) to be enough. In the latter case, he should be informed on possible light comfort problems in the future.
**Appendix C: Published articles**

*Tetri & Halonen*. Guidebook on energy efficient electric lighting for buildings. 11th European Lighting Conference. Lux Europa 9-11 September 2009, Turkey. pp. 761-768.

*Pohl*. Energy efficient electric lighting. 11th European Lighting Conference. Lux Europa 9-11 September 2009, Turkey. pp. 785-792.

*Halonen, Tetri:* Needs and challenges for energy efficient lighting in developed and developing countries. *Light & Engineering, Vol. 17, No. 1, pp.5-10, 2009.*

*Halonen, Tetri:* Lighting Efficiency and LED Lighting Applications in Industrialized and Developing Countries. The 5th International Conference ILUMINAT 2009, Sustainable Lighting. Cluj-Napoca, Romania, 20 February 2009

*Halonen:* Efficient Lighting for the 21st Century. Balkan Light 2008. Ljubljana, October 7 - 9, 2008, p. 39-44. Invited paper.

International Workshop on Visual Quality and energy efficiency in indoor lighting: today for tomorrow, Rome, Italy, presentations by Annex participants.

o *Aizenberg:* Integral approach to design building engineering systems design: Lighting, heating, air- conditioning as an effective way to energy saving

o *Bisegna & Gori:* Generic algorithms for lighting design optimization.

o *Chen & Wang &Li:* A stand-alone solar lighting system for electrodeless fluorescent lamp

o *Dehoff:* ELI and LENI – Tools for the evaluation and presentation of human aspects and energy efficiency in lighting

o *Halonen:* Lighting Energy Usage and Lighting Efficiency in Industrialized and Developing Countries – IEA ECBCS Annex 45

o *Kaase:* Optimized illumination improving energy efficiency and quality of light

o *Pohl:* Energy efficient lighting solutions – trends and chances

o *Tetri:* Usability of LEDs for General Lighting

*Tetri & Pohl:* Concepts and techniques for energy efficient lighting solutions. Fifth International Conference, Improving Energy Efficiency in Commercial Buildings (IEECB’08)

*J. Aizenberg*, Integral approach to design building engineering systems: (lighting, heating, air-conditioning) - as an effective way to Energy Saving, Fifth International Conference, Improving Energy Efficiency in Commercial Buildings (IEECB’08)

*Fontoynont M.*, Long-term economical assessment of lighting systems, Light and engineering, 2007.

*Tetri, E., Halonen L.* Future trends of energy efficient lighting. Proceedings of the 26th session of the CIE, Beijing, China, 4-11 July 2007. pp. 45-48.

*Halonen L., Tetri E. Lighting* - Energy Consumption and Energy Efficiency. Proceedings of the 4th International conference Iluminat, Cluj-Napoca, Romania, 31 May-1 June 2007. Tetri E. Energiatehokkaat valaistusratkaisut (Energy efficient lighting solutions). Projektiuutiset 5/2007, pp. 66-69.

*Bhusal P., Tetri E., Halonen L.* Quality and Efficiency of office lighting. Proceedings of the
4th European Conference on Energy Performance and Indoor Climate in Building and the 27th International Conference AIVC, Lyon, France, 20-22 November 2006, pp. 535-540.

*Halonen L., Tetri E. 2006*. IEA ECBCS Annex 45 - Energy efficient electric lighting for buildings. Lighting of work places: proceedings. Fifteenth International Symposium Lighting Engineering 2006, Bled, Slovenia. Lighting Engineering Society of Slovenia. pp. 5-10.

*Truus Debruin. 2006*. Dayligt and electric light in School buildings, Dutch Journal of Building Physics.

*Matorski Z.* Influence of new lighting technologies into electrical networks and installations. EURO-SINE Electrical networks and Installations in EU Legislation Acts. SEP – Association of Polish Electrical Engineers. Silesian University of Technology and Silesian Chamber of Civil Engineers. Ustron, Poland. pp. 125-134.

*Mantorski Z.*, Sitko A. 2006. Digital data transmission using low voltage power line. Silesian University of Technology Scientific Bulletin Elektryka, no 198, pp. 85-98.

*Mantorski Z.* Energy efficient lighting in buildings – Annex 45. XIV National Lighting Conference, Lighting techniques 2005. pp. 73-74.

*Merzwinski S.* Efficient energy consumption. Information on Silesian university of technology participation in iea programmes. zycia Politechniki slaskiej, March 2007 No 6(170), pp. 26-29.