Now that the Paris Olympics are over, the temporary air conditioning units shipped in for athletes are poised to have a second — and hopefully third — life.

There was a good amount of drama around these units. Planners initially didn’t include them in their design for competitors’ housing, opting instead for more energy-efficient options. Moreover, AC just hasn’t been as necessary in cooler climates until lately and is still relatively uncommon in homes across Europe. But heatwaves pose big risks for athletes, many of whom decided to supply their own mobile units to stay cool.

Thousands of them were reportedly ordered for the Olympic Village, where more than 14,000 athletes stayed during the Olympics. The Games came to a close on August 11th, but the AC units aren’t going anywhere yet. They’ll stay there a while longer for the Paralympics scheduled for August 28th through September 8th.

And while competitors in the Olympics had to pay for their own air conditioning, organizers say they’ll provide units to Paralympics athletes “free of charge for medical reasons, at a ratio of one for every three athletes” in an email to The Verge. The village is expected to host some 8,000 athletes during the Paralympics. Some of the people competing have disabilities that affect their bodies’ ability to regulate temperature, the email notes.

Heat was already a safety concern going into the Olympics. Beyond affecting athletes’ performance, unyielding heat can potentially also lead to exhaustion and heatstroke. Temperatures in Paris reached upwards of 35 degrees Celsius (95 degrees Fahrenheit) in Paris in July as a heat dome suffocated the Games for several days.

Similar concerns have been raised at previous Olympic events, but the risks rise each year with climate change. “The world watched athletes swelter in 35°C heat. If the atmosphere wasn’t overloaded with emissions from burning fossil fuel, Paris would have been about 3°C cooler and much safer for sport,” Friederike Otto, a physicist with an international group of researchers called World Weather Attribution, said on X on July 31st. World Weather Attribution published an analysis that found that the heatwave affecting the region that month wouldn’t have occurred without human-induced climate change.

Paris Olympic organizers faced a conundrum. Air conditioners can help people stay safe during a heatwave, but they also contribute to the climate crisis because of all the energy they burn through. ACs can also stress the power grid during heatwaves, which can lead to dangerous power outages when people need cooling the most. Urban planners around the world are trying to find more sustainable options, including installing energy-efficient heat pumps or topping buildings with gardens or white roofs to avoid trapping heat.

The Paris Olympic Village used a geothermal cooling system that piped cool water underneath the floor. Paired with other insulating design elements, the system was intended “to achieve a target temperature of 23-26° Celsius [73.4-78.8 Fahrenheit] at the hottest time of the day in a heatwave,” the email from the International Olympic Committee (IOC) says.

That just wasn’t enough to assuage competing teams’ concerns. The IOC says that the AC units were rented. After the Paralympics, they’re supposed to be refurbished and reused by the supplier.

The village will continue to rely on its built-in cooling system, part of an effort to turn it into a new “sustainable city district” after competitors leave. That includes plans for 2,500 homes, a student residence, and a hotel — all designed with the hopes of minimizing their impact on the environment.

“We tried to find a balance in the design and fit-out of the Village between a long-term objective to create a sustainable neighbourhood; and a short-term responsibility to give high-performance athletes the best conditions in which to prepare,” Paris 2024 spokesperson Arthur Fel said in the email to The Verge. “A/C is culturally widespread in some parts of the world, but not in France.”

Correction, Aug. 21st: A previous version of this story incorrectly identified Arther Fel. He is a Paris 2024 spokesperson, not an IOC spokesperson.