Thursday - January 13th, 2011

We visited a new project being developed by Grocon and LaSalle Investment Management. It is an $800mm 50 story office project to replace four existing buildings between Castlereigh and Pitt Street. There is an additional “Heritage” building on the site that will be preserved and built around which has already earned a 5 star energy rating as a result of the retrofit. The new tower will be a 6 star design and eventual as built rated building and will incorporate 1,200 kw tri-generation which accomplish the generation of electricity by burning natural gas and then uses the heat generated from that to heat water and run the HVAC system. The developers original intent was to make the building the most sustainable in the world utilizing black water recovery and recycling and wind turbine power generation on the roof. These two particular elements have come into question, but the intent is still to complete a sustainable building in the 5 or 6 star rating range. Another interesting feature was that it was designed at the city's request to not cast any shadows on Hyde park (just below the tower).

We also visited 30 The Bond. This is an operational 5 star designed and as built rated building that was completed in 2007. During excavation a sandstone wall built by early prisoners in Australia was discovered and subsequently incorporated into both the design and sustainability of the building. The stone wall acts as enormous heat sink that helps to moderate the temperature of the first four floors. In addition to this “chilled beams” provide about 90% of the air cooling with the remaining 10% provided by dehumidified fresh air that is ducted into the building. The chilled beams are a relatively new concept that requires significantly less energy than conventional HVAC. It’s interesting to note that this building used a single chiller, whereas newer designs are actually incorporating multi stage chillers that can provide more efficiency. It was interesting being in the building because you would have never known that there was no traditional HVAC, it was very comfortable. There were many design features that I had never seen including:



• Raised floors so that cabling and air could be circulated underneath the occupants.

• Perforated ceiling covering. There are no drop ceilings as the air must be able to rise up to the chilled beams to be cooled. So as the air warms up it rises and is cooled back down again and as it cools it circulates back down to the raised floor, so it is naturally always circulating.

• Automated window louvers. These louvers change position through out the day to reflect sunlight away from the building and shade the interior against the radiant energy in order to keep the space cool in the summer time.

• Automated timed lighting. The lighting will shut-off each day at 6:00pm and anyone requiring light there after must manually turn it back on for their zone for 1 hour increments.

• Green roof, the majority of the roof is covered with native plants and what is not has been developed into a lounge to host corporate events and dinners.

• Open and prominent stairs to encourage travel between levels via stair vs. elevator. The building manager quoted that they use 75% less energy on their elevator service than the average 8 story building in Sydney.