SYDNEY HARBOUR BRIDGE
SYDNEY HARBOUR BRIDGE HERITAGE PROJECT – Sylvania-Schréder LIGHTING CASE STUDY
The Sydney Harbour Bridge attracts millions of tourists every year to the famed Sydney Harbour, and the architectural and design detail contains significant heritage value. Sylvania-Schréder Lighting has been instrumental in helping to sustain the heritage aspect of some of the more intricate lighting aspects of the bridge.
The iconic Bridge was originally designed to create a sense of arrival or entry to a special place. When completed in 1932, the Bridge’s roadways were lined with distinctive bronze lantern fittings. Unfortunately, the lights produced a glow that was deemed to be of detriment to drivers as traffic volumes increased. The lanterns were removed in the 1960s and replaced with modern fittings for the time. Without much foresight into their historical significance, most of the lanterns were also unfortunately destroyed.
As the 21st century progresses, there has been an increased focus on preserving Australia’s national heritage and historical structures. Owned by the RMS (Road and Maritime Services) the Bridge’s heritage value is proudly being upheld with the RMS ensuring that any changes or modifications required to service contemporary requirements are done in a manner that are respectful to the original architecture. In 2013, the decision was made to resurrect the original bronze lanterns in an effort to both provide effective lighting whilst also restoring the original aesthetic of the Bridge’s unique adornments.
First and foremost Sylvania’s goal was to create a lighting solution that was both functional and aesthetic while maintaining existing light levels. The new lighting for the roadway, walkway and traffic had to be unobtrusive and hidden from view whilst the heritage lanterns needed to produce a soft glow to recreate the heritage feel of the original bridge, all without being a hindrance to traffic.
The lantern frame was a new replica. This was used to create the moulds for the new lanterns at a foundry in Western Sydney. Bronze was chosen as the preferred metal for its durability and because it does not require painting. As with the original lanterns, parts were sourced from local producers where possible.
Borosilicate was chosen as the glassware because of its high durability as well as its resistance to expanding and contracting with temperature changes. The Heritage fitting is designed to glow, rather than to contribute to the road lighting. The glass manufacturers asked Sylvania to nominate the type of glass and the amount of frosting that would be required to achieve the desired effect. The interior of the top dome is sand-blasted to produce this frosted diffusing light effect. Borosilicate flat glass panels were held in place with highly durable silicon gaskets and pourable silicon to allow the lanterns to remain water tight. Sylvania incorporated an additional visor over the module to counter any internal condensation. They also recommended that the RMS include two bronze breathers to ensure pressure equilibrium, which is very important to maintain a dry internal environment in the fitting. The units are sealed to IP67.
NOW FOR THE LIGHTING!
Sylvania was given a Heritage fitting frame that was used to create a mock-up version, made of acrylic panels and an LED module in order to determine the desired lighting effect. Sylvania then customized a double sided 15Watt LED fitting to be seated inside each lantern, producing a soft glow that is rated as maintenance free for 20 years with over 100,000 hours at a very low power consumption resulting in reduced energy and costs. The modules are 3000k, chosen due to its ability to reproduce a warmer light that has a similar ambience and effect to the original Heritage lantern. This warmth was chosen due to its urban design with a heritage input, demonstrating a combination of modern technology with old world charm.
The LED lights were chosen in part because of how long they last, minimizing the risk of smashing the fragile glass top domes when changing lights. Two standard 37 Watt Sylvania StreetLED streetlights provide roadway illumination in order to address the original issue of in-effective illumination. These are concealed within the light arm structures to reduce glare whilst delivering drivers with a necessarily compliant level of illumination to ensure road safety. The reduced glare allows the general public to simply focus on the Heritage fitting while furthering the photogenic quality of the bridge. The new lanterns will hang off 132 original outreaches, all located in the exact place as they were when the Bridge was constructed.
The Bridge is always a work in progress requiring constant maintenance and enhancement. The array of experts, in technical, design and engineering who contributed to the project was considerable. Upon completion of the Heritage fitting, each unit weighed 120kg, resulting in structural engineers having to sign off on each outreach. These outreaches had to be checked for structural integrity before the new installations could begin and installation is restricted to times of road closures, which are very limited.
Once completed, this restoration project will result in substantial dollar savings in energy costs alone as well as ensuring that the RMS can reduce maintenance and servicing costs. In addition, Sylvania has produced a lighting solution that meets today’s lighting standards while also restoring a heritage look and feel to the bridge. The new lighting solution provide all users of the bridge with safe and efficient lighting, while preserving all the ambience of yesteryear.