As World Heats, Energy for Air-Conditioning Could Double by 2050

The future facing a warming planet: As global temperatures rise, more people will turn to air-conditioners to ward off the heat.

But the rise in cooling buildings and other spaces, which is also driven by rising incomes, population growth and urbanization, means that the world could use more than double the electricity it does now to stay cool, according to new United Nations research published on Tuesday at the global climate talks in Dubai.

The surge in electricity use in turn threatens to drive up the very greenhouse gas emissions that cause global warming, heating the planet to even more dangerous extremes. Special refrigerant gases used in air-conditioners and refrigerators, when leaked into the atmosphere, are also potent greenhouse gases.

If current trends hold, 10 percent of the world’s greenhouse gas emissions in 2050 could come from air-conditioning and other efforts to keep cool, the U.N. report said.

“The cooling sector must grow to protect everyone from rising temperatures,” said Inger Andersen, executive director of the United Nations Environment Program. “But this growth must not come at the cost of the energy transition and more intense climate impacts.”

Many new advancements and actions — including adopting “passive” cooling technology like improved insulation and reflective surfaces — can help keep the world cooler without significantly increasing energy use, Ms. Andersen said. Bolstering energy efficiency, as well as phasing down climate-warming refrigerant gases, can also help rein in cooling-related emissions, the report said.

There’s no question the world needs more cooling. An analysis published this year by a consortium of nonprofits, governments and corporations estimated that 1.2 billion people in 77 countries are at high risk of poor health and livelihoods because of a lack of access to cooling.

Many of the world’s most vulnerable people have limited or no access to modern cooling technology, like air-conditioners and refrigerators, at home, at school or at work, the new U.N. report said. Lack of refrigeration also reduces the incomes of millions of farmers and drives food loss, and hinders universal vaccine access.

At the same time, global mean temperatures are rising. This year is “virtually certain” to be the hottest year in recorded history, the World Meteorological Organization announced last week. The past nine years have been the hottest nine in 174 years of recorded scientific observations.

As the planet warms, installed capacity of cooling equipment worldwide will triple by 2050 under current policies, the report estimated. And even with increasingly energy-efficient technology, electricity use will more than double.

That threatens to strain electricity grids, particularly in developing economies. By 2050, 67 percent of cooling capacity will be in developing countries, up from less than 50 percent now, the report said.

Much of the potential for reducing emissions lies in the world’s richest economies, according to the report. Adopting building energy codes that explicitly incorporate “passive” cooling, like designs that increase natural shade and ventilation, are particularly effective.

Those passive cooling measures — coupled with faster improvements in energy efficiency and a more stringent phaseout of high-polluting refrigerants, called hydrofluorocarbons — could reduce projected 2050 emissions by more than 60 percent, the authors estimated.

In addition, a rapid transition toward renewable sources of energy like wind and solar to power air-conditioners could further draw down cooling-related emissions.