St. Vincent’s owns and operates a large public and private hospital network in Australia with facilities concentrated in Sydney and Melbourne. Redevelopment of St. Vincent’s medical campus in Darlinghurst began in 2000 and included upgrades to the Xavier Building, a 38,000 sq. m. (409,000 sq. ft.) facility designed for both outpatient and inpatient services. The firm,, which has managed the building management systems (BMS) on the Darlinghurst campus for the past few years, called upon BuildingIQ to help reduce the building’s energy consumption.


The challenges included establishing good working relationships with the diverse areas of responsibility in a public hospital, ranging from facilities management and environmental staff, to finance and IT. The hospital’s approach was one of caution due to the significant impact HVAC disruption could have on patient care and emergency procedures. Even working in partnership with the hospital’s trusted service provider,, preliminary discussions and agreements took the better part of a year.

BuildingIQ’s baseline analysis concluded they could save the hospital about 10% of total power usage without disruption. Hospital management felt an accomplishment of that magnitude was overly ambitious and unobtainable. They said they would be more than satisfied with a 5% savings of HVAC power usage.

Key technical challenges revolved around the hospital’s long-time practice of overcooling their interior space 24/7. St. Vincent’s facilities staff had largely overlooked the beneficial thermal properties of their building’s structure, and were used to manually turning the chillers on during hot days.


BuildingIQ formed a strategic partnership with and entered into a shared energy savings contract based upon the deployment of BuildingIQ’s Predictive Energy Optimization™ (PEO) software.

The first phase of PEO was the establishment of the historic baseline of energy consumption, which was the 10% estimate presented to St. Vincent’s management when the project was authorized. The second phase was learning the thermal dynamics of the building. The third phase, optimization, began a few weeks later.

Early results were promising and as the PEO model continued to refine the parameters, savings continued to climb. The massive heat-retaining walls of the older Xavier Building were brought into play, and used to keep the interior space cool without additional forced cooling.


The results were immediate and dramatic. Within weeks of the initial optimization, total energy savings climbed from 5% to 10%, and continued to climb as the Australian summer season progressed. By the peak month of December, total savings—not just HVAC savings—reached 20%. A total net peak demand reduction of 10% was achieved. A thorough review was conducted of the baseline and savings calculations by the hospital’s management. Since transparency is one of the strengths of BuildingIQ’s platform, hospital management was soon convinced the results were genuine and spectacular.

There was no disruption to hospital operations. Nurses and doctors made unsolicited comments about how much more comfortable the hospital felt now that the overcooling had been brought under control. St. Vincent’s has been able to meet its peak load using two chillers instead of the three they used historically.
The results are shown in the two figures below.

First, the month-by-month comparison of energy consumption after implementing the BuildingIQ software (the “actual,” green bar) versus the historic baseline (gray). Second, the cumulative energy savings over the first 14 months of the program, which totaled 1.7 million kWh, or 12% of total energy consumption.


Building Energy Intelligence – St. Vincent’s Hospital

Building Energy Intelligence – St. Vincent’s Hospital

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