City West Offices is a building of 40,000m² NLA and is the new headquarters for the Federal Government Department of Education, Employment and Work Relations (DEEWR). It has achieved a 6 Star Green Star – Office Design v2 and a 5.5 star NABERS rating.

The building is situated in the heart of Canberra’s burgeoning City West region and its position as a ‘world leader’ in Green Star design ensures that its presence enriches this part of the city.

One of the key factors to the building achieving its 6 star rating was the integration of a trigeneration system. The system comprises a 1166kW natural gas-fired generator which is matched to a 1MWth absorption chiller. Additionally, there is a 750kW diesel generator which provides back-up power to the building. The gas-fired generator can also be run in parallel with the diesel generator to provide back-up power.

A holistic approach was taken towards the services design on the building to ensure that it simultaneously met performance criteria, met green targets, is easily and intelligently maintained in the future and presented itself as prime commercial office space in Canberra’s CBD.

A DALI lighting system was installed to individually address each luminaire in the building so that the lighting can be controlled in the most efficient manner.

The installation of live “Grow Walls” acted to enhance the indoor environment quality by providing an aesthetically pleasing environment whilst providing enhanced air quality. ACOR provided the artificial lighting required to keep the walls alive.

The overall lighting power density was kept to an average of 1.75W/m2/100 lux.

The indoor air conditions are maintained via a central air conditioning system utilising chilled and heated hot water for the supply air. The air handling plant houses 9 off air handling units to supply approximately 33 zones per floor. The air conditioning system operates using a low-temperature variable air volume supply system on the perimeter and centre with hot-water reheats on the perimeter only. On-floor distribution uses induction linear slot diffusers to reduce the volume of air required.

All air handling units provide economy cycle and CO2 monitoring adjustment via each on-floor return air intake. A BMS control system is used to monitor and control all air conditioning and ventilation systems. This includes automatic reporting of alarms energy usage monitoring which helps ensure that the building meets its energy targets.