Nissan’s heat-shield paint cools car temperatures by 22°F, cuts AC load

Nissan, Japan’s automobile manufacturer, has been testing new automotive paint to keep cars cool in scorching summer heat.

The new paint technology combats summer heat by cooling down car interiors and reducing dependence on the air-conditioning system. Nissan collaborated with cooling technology specialists Radi-Cool to develop this new paint.

During the testing, this new paint reduced outside temperatures by up to 22°F (12°C) and inside temperatures by 9°F (5°C).

“My dream is to create cooler cars without consuming energy. 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,” said Susumu Miura, who is leading this paint development and senior manager and expert at the Advanced Materials and Processing Laboratory, Nissan Research Center.

Paint infused with metamaterials

With rising outdoor temperatures, cars and vehicles are increasingly susceptible to overheating.

While radiant cooling paint is commonly used in buildings , its thick texture and chalky finish make it unsuitable for vehicles. Nissan set out to overcome these constraints to develop a car-friendly version with a clear finish and sprayable application.

This new automobile paint contains “metamaterials,” which are synthetic materials designed with unique reflection properties. This new paint material consists of two tiny light-reactive particles that react to light in unique ways.

One particle in the paint deflects sunlight’s heat-generating rays, keeping the paint cooler. Moreover, the real innovation lies in the second particle, which creates electromagnetic waves that oppose sunlight and disperse energy away from the automobile.

Together, the particles in Nissan’s cool paint prevent heat from permeating the car’s outside surfaces.

Car cool paint testing

Nissan began testing its new paint tech on a service vehicle at Tokyo’s Haneda Airport in November 2023. The airport’s open tarmac offered the ideal conditions to test the paint’s performance in extreme heat.

In this year-long test, the paint has been applied to the Nissan NV100 service vehicle operated by All Nippon Airways (ANA) airport services.

The cool paint outperformed traditional paint in initial tests, reducing exterior surface temperatures by as much as 12 degrees Celsius and interior temperatures by 5 degrees Celsius.

“The paint’s cooling performance is particularly noticeable when a vehicle is parked in the sun for an extended period. A cooler cabin is not only more pleasant to enter, but also requires less air-conditioning run-time to cool the cabin to a comfortable temperature,” the press release noted.

This means less strain on your air conditioning, leading to improved fuel efficiency and a more comfortable ride. This is especially important for electric vehicles, as air conditioning can significantly impact battery life.

The current paint variant has demonstrated resistance to salt, chipping, peeling, scratches, and chemical exposure while retaining color and repairability. The team is also looking at thinner formulations that preserve their cooling characteristics.

While the paint is still under development, the team hopes to eventually offer it in a range of colors for customers who want this feature. Commercial vehicles, such as vans, trucks, and ambulances, are seen as particularly suitable for this technology. These vehicles spend significant time outdoors.