Innovative Cooling System and its Applications in Singapore

Singapore and Air-conditioning

Being a tropical island situated just one degree north of the equator, Singaporeans are no strangers to air-conditioning, a 20th-century invention. Being famously known as the “aircon nation”, air-conditioning is almost omnipresent in most indoor settings. However, with global warming looming and the sea level constantly rising, it becomes increasingly crucial for Singapore to consciously minimise its greenhouse gas emissions. 

Traditional air conditioners in residential buildings are installed at individual-household levels, while modern commercial buildings usually have building-level centralised cooling systems. Such an arrangement makes achieving energy efficiency and economies of scale difficult.

District Cooling System – Central Business District

The District cooling network in Singapore was first implemented in the Central Business District (CBD). In 2006, Singapore District Cooling Private Limited, a subsidiary of the SP Group, commissioned its first underground district cooling system, with One Raffles Quay being its first customer.

The district cooling system achieves economies of scale through sharing the centralised chiller’s capacity, which is regularly maintained to operate at its highest efficiency. The length of piping currently stands at 5 kilometres across CBD. According to SP, the district cooling network has brought about 40% energy savings. In other words, less greenhouse gas was emitted by the cooling systems in CBD, helping to alleviate the urban heat island effect (UHI), which is particularly prevalent in CBD, where air-conditioning is pointed out as a prominent contributor to UHI by the URA. Rooftop spaces are also saved as building-level cooling towers are no longer needed. In addition, with the adoption of district cooling systems, buildings are more attractive to prospective tenants with high environmental, social and governance (ESG) standards. 

The district cooling system has since drawn more customers. As of the first quarter of 2022, there are a total of 18 commercial developments spanning across the Marina reservoir using the district cooling system, among which are notable landmarks such as Gardens by the Bay, Marina Bay Sands and the Marina Bay Financial Centre (MBFC). The district cooling network has recently undergone an expansion and will be expected to serve five additional buildings by 2025. It is also currently the world’s largest underground district cooling network. 

Centralised Cooling System – Tengah New Town

As the next big upcoming satellite town, Tengah New Town does not only pioneer in concepts such as car-free town centre and biophilic architectural designs but also takes on the challenge of creating a more energy-efficient air-conditioning system for the new town. In the residential context, the centralised cooling system takes a slightly different approach from its commercial counterpart. Instead of providing the cooling solution at the district level, centralised cooling provides at the building level with a centralised chiller plant placed on the rooftop of each HDB block. The centralised cooling system provides a multitude of benefits, such as cost savings and smart features, while lessening the hassle of servicing and even the need to fork out for aircon ledges for future buyers. 

Conclusion

In short, district cooling and centralised cooling systems are an evolution from the centuries-old air-conditioning technology, which helps achieve economies of scale and spatial efficiency and makes air-conditioning more environmentally friendly than the status quo. 

With its track record in CBD and Tengah New Town, more district cooling and centralised cooling systems will be implemented in more projects alike en masse in the long run, helping to bridge Singapore’s built environment towards a more sustainable future.