When temperatures climbed north of 40 degrees Celsius (104 degrees Fahrenheit) in Seville during this summer's crushing heatwave in Europe, air conditioning use jumped 23% in the southern Spanish city compared to how many hours ACs ran during the same period in 2022.
Lisbon's average AC use, too, went up by about 41% in mid-June to mid-July, compared with the same period the previous year, according to data analysis from Sensibo, a company which specializes in smart devices that can control ACs remotely to cut energy use.
While cooling technologies can save lives during deadly heat, they also threaten to worsen the climate crisis.
The energy used in cooling and refrigerants accounts for about 7% of global greenhouse gas emissions, and demand could more than triple by 2050, according to the International Energy Agency.
We've got a big problem," said Lily Riahi, head of the United Nations Environment Programme's (UNEP) Cool Coalition. "Without strong policy actions, emissions will skyrocket.