The Hospital Authority says it's making use of artificial intelligence to save energy for air conditioning, in a bid to reduce carbon emissions in public hospitals.

Yuen Pak-leung, a chief project manager at the authority, said air conditioning currently accounts for around half of hospitals' energy consumption.

"Hospital runs on 24-hour non-stop basis and provide health care services, which would consume substantial amount of energy to operate its air conditioning, mechanical ventilation, lighting and power, medical equipment, lifts, escalator, so on and so forth," he said.

Yuen said the authority is piloting an AI-controlled air conditioning system, which can save around 20 to 50 percent of energy for chillers.

"This system analyses the past performance and pattern of consumption and also to understand the possible usage trends. The AI would then learn the preferences of occupancy, their pattern and to optimise the comfort while minimising energy use," he said.

"It will enhance the comfort level due to more precise temperature and humidity control and at the same time reducing energy use because we're trying to avoid wastage," he said.

The AI-powered air conditioning system is currently being trialled in Tseung Kwan O Hospital and Queen Mary Hospital in Pok Fu Lam, and Yuen said more hospitals will be covered in the long run.

Yuen added that the authority is also exploring the use of hydrogen fuel cells for EV charging facilities, though this is still in a preliminary stage.