By continuing to use the site you agree to our Privacy & Cookies policy

THE ROOF ITSELF IS TREATED AS A LIGHT OBJECT

TECHNICAL & PRACTICE

The Berlin Olympiastadion, designed by Werner March and most famous for US athlete Jesse Owens' Nazi-bashing gold medal performances in the 1936 Olympics, has been renovated at a cost of 245 million euros (£168 million) and is being relaunched as part of 'the first ficlimate neutralfl FIFA World Cup'. Under the banner of the 'Green Goal' the World Cup organisers have set numerous targets for waste recycling; minimising private transportation to the venue; and reducing energy and water use. With the global football tournament scheduled to generate 100,000 tonnes of CO 2 solely through the transport emissions of the 3 million people attending, the neutralisers are certainly going to have their work cut out this summer.

Designed by architect von Gerkan, Marg + Partner, the upgraded and modernised stadium is ready for the start of the World Cup this week (Friday 9 June). The redesign of the architectural landmark incorporates a new 40m-high roof, which spans 68m over the terraced seating and is supported on just 20 columns, giving the venue a sense of enclosure, although the translucent roof membrane ensures that it retains the feel of an open-air stadium. In place of the previous 500 oodlights, the new design uses only 310. Instead of the traditional pole-mounted oodlighting system, which frequently gives out as much light to the surrounding night sky as it does to the playing surface - and hence operates on an extremely inefficient basis - these light fittings have been designed for maximum efficiency in terms of direction, energy used and system management. They have also been integrated subtly into the soffit of the cantilevered-steel roof canopy.

In most stadia, oodlighting is the biggest source of energy consumption, with FIFA requirements stipulating that 'the whole pitch [be] evenly lit to at least 1,500 lux. An emergency power generator will also be available which, in the event of a power failure, guarantees at least two-thirds of the aforementioned intensity of light for the whole pitch'.

The new oodlighting, which consists of 2,000W metal halide lamps, offers significant improvements over the previous system. Narrow-beam rather than wide-beam bulbs are now being used, and they are positioned at a lower angle than the old lights, which were on towers, with the result that there are no shadows cast by the players. This is less distracting for the players and also enables better viewing both for spectators in the stadium and on television. The lights are designed so that the field is illuminated while the stands remain dark, as in a theatre - a new approach to football viewing.

Helmut Angerer, of lighting designer Conceptlicht, explains that bespoke square oodlights were used because they are more 'visually silent' than traditional round fittings. In order to reduce the glare from the oodlights for spectators in the stadium, Conceptlicht developed a light ring of opal glass, which parallels the oodlights and delineates the edge of the stadium roof. Fitted with uorescent tubes whose milky light softens the contrast between the oodlights and the dark night sky, this 'ring of fire', as it has been nicknamed, visually reinforces the oval form of the stadium. Finally, the use of recessed floodlights, rather than lights on masts, reduces ambient light pollution from the stadium to the surrounding area.

The roof itself has been treated as a light object, and the lighting for the terraces and for the roof itself is located between the roof's upper weatherproof membrane and the lower membrane, which is made of a highly translucent open-weave fibreglass fabric.

Interior lighting for the stadium is achieved by continuous lighting tubes located on the radial truss structure, which uplight the interior of the membrane, and the reflected light illuminates the stands. These lights can be adjusted to change the luminosity of the roof membrane. The illuminated roof is a dramatic visual feature of the stadium redesign.

Some 4,200 luminaires have been fitted with dimmable electronic ballasts, all controlled from a centralised DALI standard intelligent stadium-management system. This arrangement of Luxmate luminaires is organised in separate groups of four to operate as a pixelated unit, so that the various colours, intensities and shapes created by the lights can be drawn across a given roof area by altering one of the adjustable variables in each pixel and the adjacent pixels.

The operation of the roof lighting can be managed so that when a goal is scored, the lights can be programmed to flash and dim in sequence to create a Mexican wave of light. As if the World Cup isn't exciting enough, this 'lumière' show is to be complemented by 'son' in the form of 'acoustic effects', whereby the light will be responsive to the sounds 'in order to create more atmosphere and excitement in the stadium.' After working the crowd into a stroboscopic frenzy, Zumtobel Staff, the lighting implementation partner, suggests that the Luxmate control technology can be adjusted so that more intense light can be directed onto particular areas of the stands to identify problems.

Similarly, the lighting pixels can be programmed to lead people to safety through vaguely subliminal light patterns, intensity and colour palette.

The refurbished stadium has almost doubled the number of seats from the original 1930s arena to 76,000, but still manages to create an intimate atmosphere in most points around its 16,000m 2 central area. In the course of the redesign, the playing field was lowered by 2.65m and the lower tier of seating in the stadium was rebuilt at an improved inclination to modern sightline requirements. The designers are adamant however that at no point in the arena will spectators be 'blinded' by the glare from the floodlighting.

Each luminaire is individually fitted with an ultratransparent 'diffuser' that directs 75 per cent of the light emitted onto the pitch, and very little is dissipated (this doesn't mean that the remaining 25 per cent is lost to the night sky - it is spread across the public arena). Because of the efficiency of the lighting design and the improved public and playing areas, the lighting layout is said to require 40 per cent less energy, but this is premised on the fact that 40 per cent fewer lamps are used than was previously the case. There is not necessarily a direct correlation here, especially given that the new lamps, installed in 155 double oodlight combinations, comprise metal halide lamps, each with a nominal 2,000W rating - that's two-thirds of a million watts, enough to power 15,000 televisions showing the World Cup. To a certain extent the energy used isn't as big a problem as the convoluted means by which the authorities try to justify how green they are.

To that end, the new international broadcasting centre, constructed to house the many journalists and technicians who will attend the tournament from around the world, is being powered by a co-generation (micro-CHP) plant (with a lowcarbon-rated energy source) of a type promoted in the latest Approved Document Part L Second Tier Document. Essentially, it is a generator that uses its heat and operates at a higher efficiency (around 97 per cent) than power-station sources, primarily because of its local production and small distribution networks. It will, according to the PR people, virtually eliminate the possibility of any power outages during the tournament.

That is because, in the days before environmental spin, this co-generation machine would have been known simply as a 'back-up generator'.

As the environmental claims of this first carbon-neutral football festival spiral out of control, it looks like Sven may well have to pick Green and leave Cole behind.

Have your say

You must sign in to make a comment.

The searchable digital buildings archive with drawings from more than 1,500 projects

AJ newsletters