Singapore, long known as an “air-conditioned nation,” is exploring alternatives to conventional air conditioning systems to reduce energy consumption and associated carbon emissions. With approximately 99 percent of private residences equipped with air conditioners, cooling contributes significantly to the city-state’s energy use and environmental footprint. Studies indicate that Singapore’s building sector accounts for about one-fifth of the nation’s emissions, with cooling representing 40 to 60 percent of a building's energy consumption.

The widespread use of air conditioning is evident along Orchard Road, where cool air streams out into the street from shop entrances, providing relief from average daytime temperatures that consistently range between 31°C and 33°C. However, traditional air conditioning units expel hot air into the environment and require electricity, often generated from fossil fuels, contributing to climate change.

In response, some buildings have adopted alternative cooling technologies (ACTs), including active chilled beams and passive displacement systems, which offer energy-saving benefits. Active chilled beams, for instance, are ceiling-mounted panels fitted with cooling coils. Water cooled to around 9°C is circulated through the coils, while small nozzles release air jets that create a low-pressure zone, drawing warm air from the room to be cooled and recirculated. This system quietly maintains office temperatures around 24°C, as demonstrated at the eight-storey Paya Lebar Green building in eastern Singapore, regarded as one of the city’s greenest structures.

Users like HR professional Renuga Shekar have noted the subtlety of the cooling system; initially mistaking the exposed ceiling pipes and panels for industrial design elements, they only became aware of the technology months later. According to DP Architects, who designed the system, energy consumption at Paya Lebar Green decreased by more than 30 percent compared to traditional air conditioning units.

Another approach, passive displacement cooling, employed at the Ports Authority maintenance building in western Tuas, uses chilled air that sinks naturally and cycles without heavy reliance on fans, reducing both energy use and noise levels. Radiant cooling, which passes chilled water through pipes or panels to absorb heat radiated from occupants and objects, is also being tested as part of the city’s cooling strategies.

A 2024 government study identified ACTs as a key component of Singapore’s plan to cut energy use by as much as 48 percent and support its goal of net-zero carbon emissions by 2050. By mid-2026, building authorities reported that 33 public and 14 private buildings had adopted some form of ACT. However, acceptance remains limited, largely due to higher installation costs and user familiarity with traditional air conditioning.

The most commonly used alternative method so far is hybrid cooling, which pairs raised air conditioning temperatures between 25.5°C and 27°C with fans. Experts note that societal attitudes toward temperature comfort need further adjustment to make higher setpoints widely acceptable.

Traditional air conditioners operate on vapor compression and refrigerants, moving heat from interior spaces to outside. While ACTs use similar principles, they aim to reduce energy by moving less cool air or shortening run times, relying on occupants’ adaptation to slightly warmer conditions. Cooling technology expert Wan Man Pun of Nanyang Technological University views these advances as positive steps that will benefit from improved control systems capable of predictive temperature adjustments. Nonetheless, he notes that no alternative currently surpasses vapor compression in efficiency.

As Singapore faces rising temperatures and humidity linked to climate change, these efforts to innovate cooling systems underline the city-state’s commitment to balancing comfort with sustainability.