Nissan is trialling an exterior paint that is intended to help lower a vehicle’s ambient cabin temperature, which would also help reduce its air conditioner’s energy usage.

The innovative paint was developed in partnership with Radi-Cool, a specialist in passive radiative cooling products, the automaker said.

The innovative paint incorporates metamaterial, Nissan said, comprised of synthetic composite materials with structures that exhibit properties not normally found in nature.

The 12-month feasibility trial began in November 2023 at the Tokyo International Air Terminal at Haneda where the paint has been applied to Nissan NV100 service vehicles operated by All Nippon Airways airport services.

“With its large, open tarmac, Haneda airport provided the perfect environment to conduct real-world evaluation of the paint’s performance under an exposed high-temperature environment,” a news release from Nissan said.

The trial is not yet concluded, but the automaker said the results, so far, are showing a 12 C reduction in exterior surface temperature and as much as a 5 C cooler interior in vehicles with the innovative paint versus those with regular paint.

The difference is particularly noticeable when the vehicle is parked in the sun for an extended period.

“My dream is to create cooler cars without consuming energy,” said Susumu Miura, senior manager and expert at the Advanced Materials and Processing Laboratory, Nissan Research Center, in a news release. “This is especially important in the EV era, where the load from running air-conditioning in summer can have a sizable impact on the state of charge.”

Nissan points out cooling paint isn’t new, but it’s typically thick and normally saved for buildings and structures, and without a topcoat it can leave a chalky residue when touched.

Nissan had to overcome various challenges to create a paint meant for vehicles, including requiring it to be applied by a spray gun, whereas cooling paint is normally applied by a roller.

Miura and the team hope that eventually the paint will be available for special orders and in a variety of colours. The paint would have strong potential for light commercial vehicles such as vans, trucks and ambulances because of how much time they spend in the day driving, Nissan added.