Central Plaza One Ground Floor Lobby Lighting Upgrade

1. Treating the Lobby as a restoration, with all building features and fabric to remain or be replicated. 2. Lighting to have consistent colour to match the surfaces they are housed within. 3. Even diffusion across lanterns whilst creating some interest with light patterns or distribution in the overall space. 4. Light emitted into the space to not be overwhelming, or flat. 5. Energy consumption had to be minimised. 6. NABERS 4.5 Star rating of the building could not be compromised. 7. Reduce proposed budgets and operating costs by 30% minimum. 8. The upgrade had to be done with minimal disruption to sitting tenants. 9. The overall environment needed to present a “wow” factor that was consistent with the buildings' image.

The problems that had been experienced with maintenance, the energy targets, as well as the overwhelming effect that the 120 ceiling lanterns had on those entering the foyer, during the day and at night convinced us that simply replacing the tubes with new LED would not meet the design aims nor achieve the desired environment. Any “wow” would have been about how overwhelmingly bright the space was. As lighting designers, we believed the space deserved so much more. Challenges like not interrupting the operation of the 800sqm lobby, its 16 lifts and five entries, whilst upgrading the lighting 16metres above the floor were secondary until could develop a lighting solution that energised and activated the space.

We came to the project because everyone knew technology was the answer, in this case, LED lighting would save energy, but despite some two years of analysis and proposals, most of the original questions seemed unable to be answered. Retention of the 1305 existing diffusers in the 120 ceiling lanterns was the main challenge as everyone before us had sought to pump enormous amounts of light (and energy) through the existing 30mm thick 30-year-old diffusers. This solution was very inefficient. We believed that the desired outcome didn't need lots of light in the space, but for the surfaces to appear bright.

Our approach was to develop a variety of special LED edge lit panels that were more efficient than a backlighting scheme because they required less light to appear bright. It also meant we didn't need to replace diffusers or paint the surfaces within the lanterns: both actions saved lots of money) as the LED panel removed these elements from the solution. We realised early in the concept development that the cost of this custom installation was in the fabrication of non-standard LED edge lit panels and so we set about productionising the replacement panels to minimise the number of different sizes, and hence the cost.

To confirm panel sizing Savills Project Management organised to digitally measure the space and confirm the lanterns sizes to +-10mm. The survey revealed 23 different size lanterns. We then developed an adaptable perimeter framing system to house the LED panels, this reduced the number of different size custom panels required to only three with seven cut-down versions of the three types being made for the irregular shaped lanterns on the perimeter of the Lobby. The developed solution also allowed us to vary the perimeter trim width and retain much of the edge framing, further reducing the installation cost and making painting of the ceiling much easier / less costly as it provided a edge for painting.

As this was a restoration project we were required to develop panels of approximately the same size and shape as dictated by the existing lantern framing. The LED edge lighting system had the same LED spacing in all panels, different brightnesses for each size resulted at 100%. We obtained samples / protoypes and tested them for brightness between each type and across two of the same type, at this point we determined that each panel had to be individually dimmed to allow brightness matching. The LED spacing had to be optimised so that the smallest fitting could be dimmed to a low level without flicker and match the larger panels that were dimmer when operating at 100%. Full-size mockups were created to test fit.

The original drivers for this restoration were maintenance and energy. The restoration project aimed to replace a system which consumed nearly 628MWhrs pa when fully operational with a system that should consume just 70MWhrs….a reduction of some 550 tonnes of carbon per annum in direct consumption. The installation should last in excess of 10 years with little maintenance and up to 20 years versus the old fluorescent installation requiring complete re-lamping every second year. This LED solution reduced waste and toxins generated by the re-lamping process.