Singapore is reinstating 19th-century underground cooling-tower technology to lower ambient temperatures across the city-state [1, 2].

The move comes as the region faces a warming climate and extreme heatwaves. By utilizing legacy infrastructure designs, the government aims to mitigate the urban heat island effect and improve public comfort during periods of intense warmth.

Government agencies, including the Urban Redevelopment Authority, began implementing the systems in 2024 [1]. The rollout coincided with a strong "super" El Niño event that brought unusually high temperatures to the region [1, 2].

The cooling technology has been installed in at least eight districts [2]. This includes Punggol, a residential area in the northeast of the city [2]. These underground towers are designed to draw heat away from the surface, providing a passive method of temperature regulation.

Officials are deploying these systems to address the immediate pressures of the current climate cycle [1, 2]. The strategy reflects a shift toward integrating historical engineering with modern urban planning to create more resilient city environments.

While the technology is centuries old, its application in a modern metropolis like Singapore demonstrates a need for diverse cooling strategies. The city continues to seek ways to lower surface temperatures as global warming intensifies [1].

“Singapore is reinstating 19th-century underground cooling-tower technology to lower ambient temperatures”

The adoption of 19th-century cooling towers suggests that modern electrical cooling solutions, such as air conditioning, may be insufficient or too energy-intensive to combat extreme urban heat. By returning to passive, underground infrastructure, Singapore is attempting to reduce its reliance on power-heavy systems while addressing the immediate risks posed by the super El Niño and long-term climate warming.