The air conditioning dilemma: Cooling homes heats the planet
Climate change, rapid urbanisation, rising incomes and population growth are driving huge demand for air conditioners (AC) globally, but particularly in developing countries.
But air conditioning’s high energy consumption and impact on the climate is often overlooked.
Without swift action, planet-warming emissions from cooling — ACs and refrigeration — could account for more than 10 per cent of total emissions by 2050, according to the UN environmental agency UNEP.
The fastest growth is predicted in Africa and South Asia. India could have 1.1 billion units by 2050, more than 10 times the number today, IEA forecasts suggest.
But even cooler countries like Britain, where residential AC is uncommon, have seen sales soar, according to media reports.
How do air conditioners cause climate change?
Air conditioning guzzles electricity. Much of this comes from burning fossil fuels, which releases heat-trapping CO2.
It also uses refrigerants which have a global warming potential hundreds or even thousands of times greater than CO2. Nearly 40 per cent of residential AC emissions are due to refrigerants, according to UNEP.
In built-up areas, air conditioners can exacerbate the urban heat island effect as they expel warm air into city streets, potentially raising temperatures by more than 1 degree Celsius at night.
Residents in densely populated Hong Kong report switching on their air conditioning because neighbouring AC units blow hot air into their apartments.
Can we make air conditioning greener?
The good news is that manufacturers are developing increasingly energy-efficient models and smart tech can ensure AC units do not unnecessarily cool empty rooms and offices.
Scientists are also innovating less polluting refrigerants and even new AC technologies that do not need refrigerants.
In 2021, two AC companies won a global competition supported by India’s government and non-profits to produce prototypes for residential units with five times less impact on the climate than standard models.
However, producing ultra-efficient ACs at an affordable price remains an issue, and they are not yet commercially available.