Wealthier countries with more stable power systems and populations better able to afford cooling are usually better able to deal with heatwaves, heat experts say.
But even there, huge demand for cooling during heatwaves can overwhelm the grid, or power can be lost during climate-fuelled disasters such as storms or floods, leaving people unprotected.
Florida, for instance, saw a 25% surge in deaths among 28,000 nursing home residents left without power in the week after Hurricane Irma hit the U.S. state in 2017, according to the Journal of the American Medical Association.
Researchers said recognising the need to invest now in renewable energy, to provide cheap and low-carbon future power to run air conditioners, was especially crucial in already hot countries like India, to keep people safe as heatwaves worsen.
“Poor countries should think about this question before they encounter it,” research He urged, noting heat mortality is already 20 to 30 times higher in India than the United States in part because “people don’t have basic access to electricity”.
Adding vast new renewable capacity could provide effective protection from heat extremes without making them worse, he said.
“As long as the electricity price from clean energy is cheap enough in coming years, there will be no restriction on how much people can consume – so they can mitigate climate change at the same time they adapt to it,” he noted.
India is currently working to ramp up renewables, particularly solar power, with $14.5 billion invested in the 2021-22 financial year, according to the Institute for Energy Economics and Financial Analysis.
Other policy measures can also help countries avoid heat deaths when power runs short, He noted.
In China, for instance, when hydropower dams have run short of power as a result of drought, the country has restricted industrial use of electricity rather than household use – hurting companies but protecting people, he said.
What is clear, the researcher said, is that curbing the use of fossil-fuel power to limit climate change is crucial to protect future generations – but it has a “non-negligible cost” for people threatened by climate extremes today.
“Climate change is already upon us and encouraging less use of air conditioning or other means of adapting to extreme temperatures can kill people living right now,” he said.
“A better approach … is to speed up the transition to clean energy and encourage people to use more clean energy to protect themselves.”