In Singapore, close to the Equator, temperatures regularly rise above 32 degrees Celsius (90 Fahrenheit) — but inside the soaring glass greenhouses of Gardens by the Bay, the country’s award-winning botanical park, it’s a pleasant 24 degrees.
The daffodils and tulips of the flower dome, along with two dozen nearby towers that are normally full of bankers, shoppers, residents, hotel guests and gamblers, are chilled by what is probably the world’s largest underground district cooling system. It’s a giant air conditioner that is attempting to solve one of the biggest problems of global warming: How to stay cool.
“As the world gets warmer, air-conditioning and refrigeration are in greater need, using up energy and emitting greenhouse gases, which in turn worsens global warming,” said Vinod Thomas, visiting professor at the Lee Kuan Yew School of Public Policy in Singapore. “This is the feedback loop we urgently need to break.”
In the past two decades, air-conditioning use has exploded, led by China, where energy demand for space cooling has grown at an average of 13% per year. That’s an increase of more than the total electricity used by the U.K. On very hot days, as much as 50% of China’s peak electricity demand is used to power air-conditioning.
Other developing countries are following. Income levels are rising in Asia, Africa and South America, and one of the first status symbols for families in hot countries who join the middle class is air-conditioning. An estimated 10 new air conditioning units will be sold worldwide every second from now to 2050. By then, around two-thirds of the world’s households could have air-con, with China, India and Indonesia accounting for half of the total, the IEA predicts.