Cool paint takes the heat out of EVs

0 0 August 09, 2024 Edit this post

Some might call it good old Toyota white.

But the pointy heads at Nissan are trialling a new paint designed to lower the cabin temperature of vehicles in summer and help reduce energy consumption of airconditioning.

Developed in partnership with Radi-Cool, a specialist in radiative cooling products, the paint incorporates metamaterial, synthetic composite materials with structures that exhibit properties not usually found in nature.

The metamaterial embedded within Nissan’s cool paint features two microstructure particles that react to light.

One particle reflects near-infrared rays in the sunlight that would typically cause molecular level vibrations within the resin of traditional paint to produce heat.

The second particle enables the real breakthrough. It creates electromagnetic waves, that counteract the sun's rays, redirecting the energy away from the vehicle into the atmosphere.

Combined, the particles in Nissan’s cool paint reduce the transfer of heat into surfaces such as the roof, hood, doors and panels.

The cool new paint could have a significant impact on EVs, helping to reduce the draw on batteries.

In November, 2023, Nissan commenced a 12-month feasibility trial at Tokyo International Air Terminal at Haneda where the paint has been applied to a Nissan NV100 service vehicle.

With its large, open tarmac, Haneda airport provides the perfect environment to conduct real-world evaluation of the paint’s performance under an exposed, high-temperature environment.

Although still in testing phase, the results to date have been impressive.

Parked side-by-side under the sun, a vehicle treated with Nissan’s cool paint has shown to reduce exterior surface temperatures by up to 12 degrees, with a 5-degree reduction in the interior temperature.

The paint’s cooling performance is particularly noticeable when a vehicle is parked in the sun for an extended period.

Project leader Dr Susumu Miura has dedicated much of his career at Nissan to exploring ways to make cars quieter, cooler and more efficient.

“My dream is to create cooler cars without consuming energy” he said.

“This is especially important in the EV era, where the load from running air-conditioning in summer can have a sizeable impact on the state of charge.”

Miura-san sees strong potential, particularly for light commercial vehicle applications such as vans, trucks and ambulances that spend most of the day out driving.