The secrets of F1 drivers’ new cooling system for 2025 season. F1 cars will feature a new cooling system for drivers.

After last season’s Qatar GP, where several drivers suffered physical ailments during the race due to the heat and high physical exertion on a demanding track like Lusail, the FIA promised swift action to address the issue.

This year, teams were already allowed to add another opening on the top of the chassis, providing more fresh air in the cockpit during hotter weekends. This simple solution was easy to implement in the short term while the FIA worked with external partners to develop a longer-term alternative.

After months of research and on-track testing, the F1 Commission approved kits to improve driver cooling in mid-November. To understand the objectives, behind-the-scenes development, and functioning of the system, Motorsport.com interviewed Chillout Motorsports, the company that collaborated with the Federation and teams to create it.

The U.S.-based company is involved in projects beyond motorsport, with its technology also extending to sectors like medical, military, maritime, aerospace, and automotive industries. In motorsport, Chillout Motorsports operates on multiple fronts, developing systems for managing Formula E car battery temperatures during charging and cooling solutions for drivers across categories like WEC and NASCAR.

Development of a system suitable for F1 began between January and February 2024, just months after the Qatar GP highlighted the problem. Chillout Motorsports was approached by the FIA in collaboration with the teams to adapt the cooling system already used in other categories for F1 cars.

The system debuting in 2025 is rooted in Chillout Motorsports’ “Cypher Pro Micro Cooler,” but redesigned and miniaturized to meet the demands of open-wheel racing teams. Let’s explore the challenges in creating this project and how it could make a difference for drivers.

The Underrated Technology in the Cooling Shirt
The cooling system comprises two main elements: a box housing miniaturized components (a micro-compressor, an evaporator, and a condensation unit) to keep the liquid cool, and a fireproof shirt worn under the suit. The shirt features a network of tubes, totaling about 48 meters in length, arranged to wrap around the driver’s chest and back. These tubes, connected to the box, carry a cooling fluid (air, water, or a saline or glycol solution) to refresh the driver in the cockpit.

According to Charles Kline, the company’s founder, the most challenging aspect was certifying the fireproof shirt due to the FIA’s stringent safety requirements. “We were already working on an FIA-approved version before they contacted us. It’s a challenging project because FIA rules on fire safety are very strict. But our goal wasn’t just to make an FIA-approved product but one that was highly functional and lightweight.”

This complexity extended to the tubes, which had to meet fire resistance standards while remaining functional. Hundreds of tests resulted in a structure comprising four different materials to ensure conductivity, flexibility, and resistance. Initially, the tubes were placed between two layers of fabric, but years of testing yielded a formula for fire-resistant, conductive, and flexible tubes.

The tubes cannot simply be glued, requiring a complex three-stage bonding process. “Once we found the right formula for the tubes, bonding them added another layer of complexity,” Kline explained.

Finding Space on 2025 Cars Wasn’t Easy
For teams, the system was entirely new and untested on single-seaters, adding challenges to its integration. Current cars weren’t designed with extra space for such systems, so innovative solutions were needed to fit the components.

Paradoxically, redesigning the box containing the necessary cooling elements was less challenging than deciding where to place it. The box components, adapted from other categories, were encased in a carbon fiber structure to suit F1’s requirements. Each team had specific needs, requiring extensive collaboration to determine suitable placements.

“Creating the cooling system itself was easy. What was more complex was figuring out how to fit it into F1 cars, as these vehicles have no space for additional systems. We tested placements behind the pedals, in the sidepods, behind the seat—everywhere,” Kline noted. For 2025, each team will have a tailored solution, with the regulations allowing greater flexibility in placement.

Weight: The “5kg” Regulation Isn’t Entirely Accurate
Another critical aspect was powering the system. The FIA increased the car’s minimum weight by five kilograms for races requiring the device. However, the system itself weighs under two kilograms, with the shirt and cooling fluid adding just 300 grams. The additional weight accounts for an external battery pack, as modifying the electrical configuration for 2025 alone was deemed impractical.

In 2026, with new car designs, an external battery won’t be necessary, as the system will draw power directly from the car. This will reduce weight and improve integration, avoiding the need for a battery meeting stringent safety standards.

New Chassis in 2026: Easier Integration
From 2026, cars will be designed from scratch to include the system, making installation simpler and quicker. Regulations mandate the system’s use when ambient temperatures exceed 30.5°C, with teams notified 24 hours before a sprint race or race. Installations must be feasible between sessions, emphasizing modularity and ease of use.

By 2026, standardized prototypes may replace bespoke solutions for each team, streamlining production and reducing costs. Currently, safety-related expenses for this system are excluded from budget caps, but this may change in the future.

How Much Will It Cool Drivers?
Although the system could significantly lower driver temperatures, it’s designed to operate within a range that ensures comfort and physiological balance. Cooling a driver from 39°C to 36.5°C is achievable, but overly low temperatures could hinder blood flow and performance.

The optimal operating temperature is around 15°C, providing comfort and reducing heart rate and respiration without overburdening the body’s regulatory systems.

Drivers Are Enthusiastic About the Cooling Kit
The system not only combats heat but enhances physical and mental performance by reducing stress. It has garnered positive feedback from drivers, with some expressing a desire to use it in every race.

“Drivers love this system and would use it every race if possible. Hearing a Ferrari driver [Charles Leclerc] say he’d want it every time was fantastic,” Kline shared. Chillout Motorsports, in collaboration with the FIA, has taken a significant step toward making F1 safer for drivers.