The advancement of digital technology has led to increased demand for data centres in South Africa. To keep up with the demand, these facilities are required to expand rapidly when needed, and the related substations also need to expand to meet the power demands of the centres.

Trafo Power Solutions MD David Claassen says that modular substations have emerged as an ideal solution for accommodating the expansion of data centres over time.

“Typically, data centres start with large structures that are only partially equipped with servers and related equipment, usually about 30% to 40%. The strategy is often to set up a cost-effective facility to serve the initial customer base and expand the infrastructure as this base grows,” he says. “Modular substations offer the advantage of scalability, allowing data centres to start with the required number of substations and add more as demand increases.”

Data centres operate 24/7 and use backup systems such as diesel generators and uninterruptible power supplies (UPSs) to ensure continuous operation. These backup systems can also be scaled up by adding units as needed.

“Modular substations are the preferred choice due to their quick design and construction capabilities, with the repetitive nature of manufacturing facilitating rapid production, and economies of scale in material requirements,” notes Claassen.

Trafo Power Solutions usually supplies dry-type transformers and medium voltage switchgear to data centre substations. These units step down incoming medium voltage power for low voltage servers and ancillary equipment on racks with the substations designed to seamlessly interface with other aspects of the data centre including low voltage distribution, medium voltage switchgear, UPS systems, and the overall control and monitoring system.

The company notes that its  energy efficient dry-type transformers ensure efficiency with some of the lowest losses globally. In addition, the air-cooled transformers are said to require minimal maintenance compared to conventional oil-filled transformers, reducing operational costs and minimising downtime.