Spli

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6 m

FOR THE FIRST TIME, LEDS MEET THE CHALLENGE OF URBAN LIGHTING, COMBINING PHOTOMETRIC PERFORMANCE AND VISUAL COMFORT!

As part of the renovation of its seafront - the Riva - the city of Split chose Schréder for this world

first, using “Cree” LEDs which have only just been launched on this constantly evolving market.

The Riva is a must-see attraction for the millions of tourists who come to Dalmatia each year to

visit the hundreds of islands scattered along the length of its coast.

Fifteen luminaires have been installed, each one incorporating 180 high-power LEDs which

diffuse a remarkable warm, white light (3000 K). The luminaires comprise 45 modules (IP 67),

each equipped with 4 LEDs. Each module is orientated in a precise way to achieve a specific goal,

which is to master light. Indeed, LEDs provide a very directional lighting, which requires extreme

precision in their orientation when they are used in urban lighting applications. This was the

challenge which was taken up by the Schréder designers and engineers.

The first measurements highlight what is also clear to the

objective observer: an average illuminance of 32 lux, with an

overall uniformity of 40%.

Officially inaugurated on 7th May 2007, this focal point of Croatian

social life has already welcomed thousands of visitors, who are

sure to have appreciated the visual comfort provided by this new

type of urban lighting while enjoying a relaxing stroll.

LEDs: a world first

Schréder developed and manufactured this tailor-made solution

in collaboration with the architectural studio 3LHD, the urban

furniture designer Numen/For Use, the lighting designers

Nova-lux and ZTT Zagreb, its exclusive distributor in Croatia.8m

Eave

= 32 lux

Overall uniformity = 40%

19,5 m

BRIGHT LIGHT OR LOW LIGHTLEDs emit a directional flux, making it possible to meet

the architect’s requirement of lighting the main thoroughfare

very precisely, with the seafront promenade remaining in

semi-darkness.

Those enjoying a walk in the area therefore have the choice

of heading towards the light or towards a space with a more

intimate ambiance.

VISUAL COMFORTEach luminaire incorporates 180 high-power LEDs

which diffuse an exceptional warm, white light

(3000 K), a source of visual comfort. The luminaires

consist of 45 modules (IP 67), each fitted with 4 LEDs.

μR® (micro-reflector)Opposite the lighting columns fitted with

LEDs, there are support frames for awnings

incorporating floodlights specially developed

for this application. Each floodlight consists of

a sealed IP 66 optical compartment with a μR®

micro-reflector with a 35 W metal halide lamp

with ceramic arc tube.

These floodlights will illuminate the terraces

which are soon to be renovated. Other floodlights

(70 W), also integrated into the lighting columns,

illuminate the sidewalk running along the

building façades.

DYNAMIC VARIATIONA dynamic variation system controlled using the DALI

protocol makes it possible – via lines of 3 modules - to create

various fun effects according to the ambiance required.

As the modules are managed separately, this system also

allows the initial photometric distribution to be modified,

a factor which therefore helps to save energy and extend

component life.

DIANA and ZLATKO GALÍC of Nova-lux are the lighting designers

behind this project.

Why did you choose to use LEDs for public lighting? We chose LEDs because we wanted a very directional lighting. Our design was based on illuminating

the esplanade clearly, while leaving the seafront promenade in semi-darkness. Using LEDs meant we

could prevent light from invading that space.

Our aim was to achieve a comfortable colour temperature, neither too cold nor too warm. We initially

opted for a combination of white LEDs with some amber coloured LEDs to create a warm atmosphere.

Then Schréder offered us LEDs which matched exactly what we were looking for, so that we did not

need to use combinations, which are not always visually attractive.

How did your cooperation with the architect in charge of the project, Sasa Begovíc, proceed?The architect had a view of the ensemble which was consistent in all details, and the lighting had

to fit in with that view. We chose to use public lighting with LEDs, allowing the promenade area to

remain darker, because the architect did not want the renovation of the esplanade to disturb people’s

habits. This seafront promenade is where young lovers go for a stroll and we wanted to respect that

tradition! It was necessary to offer local people the choice of walking in the light or strolling in a more

intimate space.

What were the basic criteria which this lighting project had to meet? When this project was presented to us, the first and main parameter was to achieve an excellent

uniformity of illuminance at ground level. We initially went for a traditional solution based on light

conduction. Then we realised that LEDs could also meet this challenge. And what’s more, meet it better!

A world first with LEDs, it must have been quite an adventure? When we see the results, it certainly has been quite an adventure, but it has also been a race against

time. To satisfy the lighting designer, we had to develop this project in 3 months.

In this short period, we produced a real public lighting luminaire which offers the same photometric

performance and the same standard colour temperature for this type of application as well as an

excellent uniformity of illuminance.

All of this has been achieved! Moreover, when you look at this installation, you are also struck by the

very low glare generated by the LEDs.

Which LEDs did you recommend?We suggested a completely new type of LED. These LEDs produce a warm white light, which is visually

very comfortable and pleasant. Furthermore their output is 52 lumens/watt, which is nothing less

than remarkable.

We would also like to point out that these LEDs have no problems with uniformity of colour.

How did you deal with the photometric aspect of this LED application for public lighting? As LED lighting is very directional, we had to perfect an accurate system for positioning the LEDs in order

to achieve excellent uniformity and to illuminate precisely the spaces which had to be illuminated.

We were able to manage this aspect thanks to the Schréder R&D Centre, which used calculation software

to specify the optimum photometric design and then validated the design on the goniophotometer in its

test laboratory.

The illuminance obtained is perfect because the specification required us to provide a minimum

illuminance of 15 lux and we achieve an average of 32 lux.

To ensure that this world first was a success, Schréder involved its LED

development department at Bornem in Belgium,

as well as its Research and Development Centre.

Sebastian Esposito is one of the

technical developers for this project.

Why was a dynamic variation system incorporated? There was a requirement to create dynamic effects

for reasons of ambiance. This dynamic variation

system designed by Schréder really can generate a

great many styles of lighting and festive effects.

Furthermore - and this is not a negligible factor

- the dynamic variation system also makes it

possible to reduce energy consumption by varying

the intensity of all the modules or by keeping

some modules at maximum intensity and others

at 30% or 50% intensity.

As for the photometry, the light distribution can be

modified by switching certain modules off or on,

or by varying the intensity of some of them.

If necessary, just a limited area of the promenade

can be illuminated and the rest left in darkness.

There are tremendous possibilities for photometric

and festive lighting, and for saving energy, not to

mention the extension of component life when

the lighting is used less intensively.

www.schreder.com

the urban light