In Parisian apartments, the air conditioning dilemma is heating up tempers

"It was up to 41 degrees Celsius at my house during the last heatwave. I didn't think it was possible," sighs Marion Lafuste, who lives in an attic in the northeast of the capital.

"The ice packs in front of the fans, the shutters down... it's anecdotal," laments this 40-year-old mother. Without the "chance of being able to take refuge in the countryside," she would undoubtedly have bought air conditioning, despite the "ideological problems" it poses for her. "We're standing on our heads because it worsens global warming. But now, I no longer judge those who have it."

On the top floor of her building in the 18th arrondissement, Martine Bontemps is also suffocating but doesn't "give in." She prefers the ceiling fan solution, which she asked her landlord to install.

"Tipping point"

Ruben Arnold has equipped himself with a portable air conditioner, which is certainly not optimal, but it allows him and his young children to "hold on." At the cost of a tug-of-war, since this director of an energy performance diagnostic (EPD) start-up is well aware of its harmful effects. "Even though we know it's a selfish pleasure, there comes a tipping point where all arguments disappear," confides this 47-year-old father.

"Being too hot is just as unbearable as being too cold. Comfort temperature is a normal demand," says Anne Ruas, a geographer at Gustave Eiffel University.

Particularly dense and mineral, Paris could experience heat peaks of 50°C by 2050, and the number of tropical nights is expected to increase according to Météo-France.

These nights, when temperatures do not drop below 20°C, prevent the body from recovering and can lead to excess mortality. As was the case during the 2003 heatwave, when approximately one-third of deaths among the elderly occurred at home.

This is one of the arguments put forward by Sophie Julini, 53, whose air-conditioned apartment offers her 86-year-old mother a few hours of coolness.

According to a recent study by the Paris Urban Planning Workshop (Apur), air conditioning has not yet "saturated the Parisian streetscape" as in other major cities, but it "continues to develop".

Unlike offices, Parisian apartments are still not very air-conditioned, "but it is likely that the acquisition of this system will follow an exponential growth," notes this unprecedented work, which mapped the heat discharges emitted by the devices using thermal cameras.

"Maladaptation"

The trend is expected to increase with the development of tourist rentals in the neighborhoods "to meet the expectations of an international clientele," Apur predicts.

The phenomenon remains difficult to quantify, however, because it mainly involves auxiliary air conditioners installed informally.

But "across the entire housing stock, we are indeed seeing a fairly strong trend towards the development of air conditioning, which is very problematic," confirms Karine Bidart, director of the Paris Climate Agency (APC).

This agency, created by the city of Paris to help with the ecological transition, is doing everything it can to prevent the spread of this "catastrophic maladaptation" to global warming, she explains.

"Several studies predict that a massive increase in individual air conditioning would warm the air by two degrees," points out Dan Lert, deputy mayor of Paris in charge of the climate plan.

"We understand that this is a last resort, especially for vulnerable people. The problem is considering air conditioning as the reflex to have, when there are less expensive and more effective solutions," argues Frédéric Delhommeau, housing and energy director of the APC.

Starting with energy renovation, including zinc roofs, which are real "frying pans." Except that "a third of renovation projects are blocked or slowed down by the Architects of Buildings of France (ABF), who put heritage before people's health," laments Dan Lert.

For Anne Ruas, Paris can still do without individual air conditioning, but not for long, as its mineral content is difficult to compensate for. "Rather than saying that we shouldn't use it and making people feel guilty, it's better to ask ourselves how we'll do it, by thinking about the most virtuous systems possible," observes the researcher.