Letters | How Hong Kong can lead the warming world on smart air con use

The advice is there, Hong Kong just needs to act on it. Circulation fans can spread the cool air from air conditioners and reduce their use, while smart thermostats can efficiently tweak temperature settings

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Hong Kong could easily have as many as three air-conditioning units per person. Photo: K.Y. Cheng

Published: 8:30am, 24 May 2019Updated: 8:30am, 24 May 2019

I write to respond to Kanis Leung’s report on the Consumer Council’s recent test result on air conditioners sold in Hong Kong, “Most air cons in Hong Kong not as effective as claimed, study finds” (May 15).

Hong Kong has 2.5 million households and over 350,000 small and medium-sized enterprises. Looking at the number of air-conditioning units installed in any building (excluding commercial offices which may be using heating, ventilation and air-conditioning systems), as well as restaurants, offices, and streetside stores installed with split-type air conditioning units, my estimate is that our air-con penetration rate is easily three units per person. According to the Electrical and Mechanical Services Department, air conditioning accounts for 34 per cent of Hong Kong’s annual energy consumption.

This is a climate and energy demand management problem not unique to Hong Kong. Asia and others around the world have the same problem. The Japan Refrigeration and Air Conditioning Industry Association, Singapore’s Eco-Business website and the International Energy Agency have all published reports on this.

Concerned? I hope you are by now. The sustainable use of air-conditioning should be Hong Kong's first smart-city campaign, so as to lead the world by example.

Firstly, we should promote the use of smart circulation fans to help distribute the cold air produced by air conditioning units. This is proven and well supported by scientific research to be effective in giving good comfort. You reported on this back in 2014 and our utility company CLP and the Electrical and Mechanical Services Department have both been advocating this method on their websites for public education.

Secondly, we should promote the use of smart control technologies. As the Consumer Council has suggested, adjusting the temperature setting periodically makes sense. The government should take the bold step of adopting and subsidising the installation of smart “internet of things” devices to control air conditioning units for taxpayers. The utility companies in Hong Kong could also learn from companies in the United States that provide rebates if a household installs a smart thermostat.