Skyring Terrace Brisbane Case Study

Project: 100 Skyring Terrace– Brisbane, QLD

Johnson Controls facility performance team helps boost energy efficiency at Brisbane’s #1 NABERS rated office building in its class for Growthpoint Properties Australia.

When the Johnson Controls facility performance team assessed the mechanical plant operation at 100 Skyring Terrace, they identified the potential for substantial reductions in the building’s energy consumption by optimising the HVAC plant operations and control functionality.

A building’s base energy consumption is critical when managing energy efficiency and sustainability. Of the major components making up base building services, the central chilled water plant, air side systems and mechanical equipment consume the largest proportion. Optimisation of these components was a key priority for the building owner, Growthpoint Properties Australia, who was looking to improve efficiencies and control costs.

100 Skyring Terrace has a net lettable area of 24,665 sqm and high sustainability credentials. The site’s central chilled water plant consists of 3 x Smardt-Powerpax water cooled chillers serving 11 centrally located air handling units. The system is monitored and controlled using the Johnson Controls Metasys® building automation system. At the time of the building’s practical completion date, in December 2014, it was modelled to meet a minimum 4.5 Star NABERS (National Australian Built Environment Rating System) rating which was achieved after the initial 12-month NABERS assessment.

Recently, the Johnson Controls facility performance team identified and implemented further sustainability initiatives in conjunction with the Johnson Controls BMS maintenance and service delivery team. This has seen the building increase its NABERS energy rating to a class leading 6 NABERS energy star rating.

As part of its ongoing commitment to reducing its impact on the environment, Growthpoint Properties Australia tasked CBRE and Johnson Controls with reducing the building’s electrical consumption. 

Working closely with the building operations manager from CBRE, Steven Pringle, the Johnson Controls team began the process of reducing the building’s electrical output and improving the NABERS rating whilst maintaining the comfort of building occupants. Johnson Controls takes a holistic approach to HVAC facility optimisation and uses a methodology that encompasses both the air side (air handling unit and associated plant) and the water side (chiller water plant and condenser water plant) to ensure the most efficient overall outcome is achieved without impacting tenant comfort.

The Johnson Controls facility performance team initially gathered historical operational and energy consumption data from the Metasys BMS (Building Management System) and EMS (Energy Management System), where they identified that significant savings could be achieved through an initial review of minimum variable speed drive limits and static control setpoints. 

Following this success, a pilot project was initiated after further opportunities were identified by optimising the air handling unit (AHU) through floor static pressure setpoint management control and optimisation. The results of the pilot project (Figure 1.) resulted in the rollout of this strategy across all building air handling units.

The scope of work incorporated:

• Ongoing partnership engagement to identify sustainability opportunities
• Preliminary works testing inclusive of data gathering and return on investment calculations (ROI)
• Implementation of AHU static pressure setpoint management software
• Implementation of chiller plant optimisation software inclusive of chiller plant setpoint and variable chilled water flow management software
• Tuning and data verification to meet targets
• Weather API integration with forecast optimisation of setpoints.

Outcome
Johnson Controls combined its extensive HVAC knowledge and strong customer relationship with CBRE to deliver a substantial 159,687 KWh base building energy reduction in the first year (ref. Fig 1) from initial cooling tower and airside optimisation. After 24 months, a 383,066 KWh reduction was calculated through decreases in central chilled water plant electrical consumption over the following seven months (ref. Fig 2, October 19 – May 20). The facility performance team achieved these substantial energy savings by implementing Johnson Controls chiller plant optimisation (CPO) software.

The entire project was completed using existing HVAC plant equipment and no loss of services. The 100 Skyring Terrace facility has achieved and is set to maintain a 6 Star NABERS Energy rating.