Image by Two Oceans Air Conditioning. Image by Two Oceans Air Conditioning. www. refrigerationandaircon. co. za RACA Journal I August 2025 33
Project disruption to university operations. While the chilled water plant and the distribution network to the buildings fall under the scope of this project, the internal HVAC system within each individual building is being managed separately by other engineers, necessitating close collaboration between all involved parties.
Despite the focus on a centralised system, the project has not been without its challenges. Lombard highlights significant space constraints for the new plant room as a primary hurdle. This necessitated multiple design iterations and even a relocation of the plant room after the initial tender process. Furthermore, the sheer size of the equipment and the complexities of interfacing with various stakeholders across different buildings required meticulous planning and coordination.
Beyond energy efficiency and simplified maintenance, Stellenbosch University ' s cutting-edge HVAC project incorporates several unique features, including a robust electrical redundancy system and a meticulously planned two-phase implementation on the motor control centres( MCCs).
An important element of the central plant design is its electrical infrastructure. The plant room houses two independent electrical transformers, each feeding a dedicated HVAC MCC. These are interconnected via a bus coupler( a device, typically a circuit breaker, that allows connection between two busbars- electrical power distribution lines- without interrupting the power supply and without creating hazardous arcs), providing a critical layer of redundancy. Should one transformer experience a failure, the system can be manually configured to draw power from the operational transformer to both MCCBs, ensuring continued operation, albeit with potential load shedding of nonessential equipment. This design allows for uninterrupted cooling and heating even during maintenance on one of the transformers or in the event of an electrical fault. As Lombard emphasises, this feature provides significant operational flexibility, allowing maintenance to be performed on one chiller, for instance, while the corresponding transformer is offline.
Though the university has embraced solar power initiatives, these are primarily implemented at the individual building level due to space limitations on the central plant ' s roof, which accommodates the cooling towers and air-cooled machines. However, the energy efficiency gains from the central plant itself, particularly the hot water storage for winter heating, are substantial contributions to the university ' s sustainability goals.
University of Stellenbosch heat exchanger.
University of Stellenbosch pumps.
Image by Two Oceans Air Conditioning. Image by Two Oceans Air Conditioning. www. refrigerationandaircon. co. za RACA Journal I August 2025 33