Sweltering summers are making an AC a lifesaving device. But despite the heatwaves, millions of Americans simply can't afford it.

The heat in swampy New Orleans, Louisiana is so pervasive that locals say the weather is a mix of mostly summer with other seasons scattered in.

Jeffrey Elder, medical director for emergency management at University Medical Center New Orleans, sees a lot of patients experiencing heatstroke. "We see it, unfortunately, every summer in a few different ways," he says. "It could be someone who's elderly who just doesn't use the air conditioning, or can't, or something's broken, and they are home alone and are later found by someone in an altered state of heatstroke."

Children and the elderly are especially susceptible to heat, he adds, because they are less able to regulate their own body temperature.

By the time patients show up at the emergency room, it's often become a true medical emergency. Patients are usually in an altered mental state, some unconscious, with internal body temperatures of 103F (39.4C) or higher, says Elder. The first course of action is to cool them down with ice baths, he says. (Read about what to do if you think someone has heatstroke and how to stay cool in a heatwave).

As climate change leads to hotter summer temperatures, breaking global heat records year after year, climate experts say to expect warmer, more frequent heatwaves. At the same time, researchers and community advocates tell the BBC that the health of Americans is at risk as people struggle to afford air conditioning (AC), which can help prevent heat-related illness and death.

The easiest way to avoid heatstroke is to stay out of the sun and stay cool, says Elder. Keeping inside spaces cooler using AC has been found in communities like Detroit, Michigan, to be a top deterrent to overheating in the summer months. But it's a luxury not all Americans can afford.

In 2020, nearly 34 million households across the US experienced energy insecurity, meaning an inability to afford their basic energy needs such as AC and heat, according to a survey by US Energy Information Association, a government agency. That was almost a quarter of all US homes at the time.

"Access to air conditioning is something that's important around here [in New Orleans]," says Elder. "Not only just having the access, but having access to good, working air conditioning, not having substandard construction."

Mark Wolfe, an energy economist and executive director of the National Energy Assistance Directors Association (Neada), which helps states with energy assistance programmes, says concerns about the long-term impacts of heat across the country are relatively new. "A couple years ago, you'd have a heatwave that lasted maybe a day or two," he says. "You can be in an overheated apartment for a day. You can't be in it for a week. If you're in it for a week, you can die." (Research shows heatwaves have already become longer and more intense around the world).

In 2020, nearly 25 million households reported reducing or going without food or medicine to pay for energy that year. Some 12 million households – one in every ten – received a disconnection notice.

The climate impact of AC

AC is itself a driver of climate change, responsible for around 3% of global greenhouse gases globally. It's also an essential tool for protecting people from rising global temperatures, meaning AC emissions are expected to increase in the future.

However, research shows using the most efficient air conditioners powered by renewable electricity, combined with better designing and improving cities and buildings to handle heat, could go a long way to curbing these emissions.

The energy burden is disproportionately high for poorer Americans. Low-income households spend roughly 10% of their income on energy while nationally Americans spend 6% on energy, according to a

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