Royal Alexandra Hospital Cooling System Upgrade

The Royal Alexandra Hospital (RAH), located in Edmonton, Alberta, is one of Canada’s largest hospitals operating with over 869 patient beds. The facility is home to several essential medical centers, including the Eye Institute of Alberta, CK Hui Heart Centre, Indigenous Health Program, Orthopedic Surgery Centre and the Louis Hole Hospital for Women. In addition, various departments within the University of Alberta’s Faculty of Medicine and Dentistry are headquartered within the RAH.

Retained by Alberta Health Services (AHS), Williams Engineering (WE) acted as the Prime Consultant and provided mechanical, electrical and structural engineering services for the design, construction administration and warranty phase to replace of a 350-ton chiller with a 2000-ton chiller. WE also assisted AHS in the procurement of the Prime Contractor, who completed the cooling system upgrade based on WE’s Issued for Construction (IFC) drawings and specifications.

The project originally involved a review of the previously completed Chilled Water Study Report and the existing site conditions as related to the cooling system repairs, chiller replacement, and the cooling tower controls upgrade. During the initial site review of the chiller rooms equipment? it was noted that a new chiller would not fit in the space left by the removal of the existing chiller without relocating two pumps, a heat exchanger and many of the existing chiller room to make space for the water lines. As a result, the process would require an extended shutdown of the chiller plant. This approach would significantly affect the operations of the facility, especially given the continuous cooling requirements of the hospital. As a result, WE proposed an alternate design solution that separated the scope into two phases.

Phase one included adjusting how the injection flow of the secondary bridge valves are controlled, installation of variable frequency drives (VFDs) on pumps, installing control valves and modifying the existing free cooling loop. This phase was completed in the fall of 2019. The completion of the first phase resulted in the secondary chilled water flow dropping from over 250 litres per second to under seventy liters per second, allowing for substantial energy savings. WE performed the final commissioning of the system to ensure design requirements were met and equipment was operating as anticipated.

Phase two included the addition of a 1,000-tonne magnetic bearing modular chiller and a cooling tower. The design intends to control the new chiller and pumps in a manner that will allow the primary chilled water flow to match the secondary flow. This strategy stages the new chiller modules and the existing chillers to maintain equal flows. WE completed the designs for phase two; however, construction has been put on hold until funding is available and is expected to continue in the near future.

The upgrades to Royal Alexandra Hospital’s cooling system allow for significant capacity increases as the facility continues to grow and serve larger populations, in addition to increased efficiency. As Edmonton and its surrounding communities grow in density, it is critical for the hospital’s cooling equipment to be optimized and hold space for future expansion.  These investments into our healthcare system ensure that communities are cared for and provide workers and those in need with safe and reliable critical infrastructure.

“Williams Engineering (WE) completed the design and construction administration for the Royal Alexandra Hospital Chilled Water System Upgrade project under my portfolio. The project was to upgrade our entire campus chiller plant, increasing capacity and efficiencies. WE was able to help Alberta Health Services (AHS) identify operational and controls adjustments to achieve our required results without having to add chiller capacity. They helped us refine the project to suit our ultimate facility goals within the design budget and schedule. WE has always been an integral team player and represented the best interests of AHS. I consider WE to be a top notch firm and would recommend them for future design work.” – Thomas Shaw, Project Manager, Capital Management, Royal Alexandra Hospital