“White cars are cooler,” goes the common logic. Many have investigated the matter, and by and large, there seems to be something to it. But Nissan isn’t simply content to slather its cars in regular white paint. It’s developing an extra-special paint to keep cars cooler when the sun is beating down.
The Japanese automaker has been working with Radi-Cool, a company that specializes in radiative cooling products. It creates coatings which minimize absorption of heat from the sun, while radiating away as much heat as possible.
The hope is that this could have benefits to both comfort and efficiency. After all, nobody likes getting in a hot car, nor waiting for the air conditioner to bring the interior down to a less-scorching temperature. But what of the numbers?
Fear not. Nissan is doing real science here. Thus far, its efforts have netted some real gains. Its new cool paint was able to slash surface temperatures by 21.6°F, and interior temperatures by 9°F, compared to a similar vehicle coated in conventional automotive paint. That’s a significant improvement, if not game-changing. It could make a car far more comfortable to enter on a hot summer’s day.
Radi-Cool notes that an ideal coating would absorb precisely zero solar radiation, while also radiating heat away at the same time. Creating a perfect reflector isn’t really practical, but it is possible to engineer a paint to absorb less heat and radiate more compared to traditional coatings.
The new extra-cool paint works by embedding two types of “microstructure particles” in the finish. One type is used to reflect near-infrared light from the sun, reducing the amount that would traditionally be absorbed by the paint. Just like regular white paint reflects more solar radiation than darker coatings, this new extra-cool paint reflects even more again. The other type of particle is used to boost the emissivity of the paint—a measure of how effectively it releases heat as electromagnetic radiation. Effectively, the new coating releases more heat as infrared energy, keeping the car cooler.
These coatings already exist, though they are typically used on buildings, not vehicles. They are normally quite thick paints which are applied via rollers or brushes. The aim of the research effort was to create a suitable version of this paint that would work in an automotive context. That meant developing a coating that would work in a typical spray applicator as is used on automotive production lines, as well as work under a clear topcoat to meet base standards for visual appeal.
The paint has been in development since 2021. Over 100 samples have been tested thus far. The team’s best effort has netted a paint that gets down to a thickness of 120 microns, or roughly six times that of typical automotive paint. The coating has also met requirements for resistance to scratches, chipping, peeling, and salt. Work is ongoing to reduce the coating thickness and improve its readiness for production, including developing it in different colors other than white.
It’s an interesting technology and one that could net real benefits. At the same time, its impact might be obscure enough to make its uptake unlikely, depending on cost or its practicality. Automotive paint is a very mature technology, with much work expended to create reliable, attractive coatings that last as long as possible. Making drastic changes to paint could pose real risks down the line if the new coating is not as reliable as customers hope for.
Still, it’s clear to see that Nissan is working hard to make its cars cooler than ever. In this case, quite literally.
Image credits: Nissan, Radi-Cool
Seems inconsequential compared to Smart Glass.
https://en.wikipedia.org/wiki/Smart_glass
(I’m saying this with snark, because there’s obviously more to it, but:)
Ah, good, just what we needed–more reasons to get white and grayscale cars!
Now they need to do the primer, since that’s all that is left on most Nissans, once they’re sold off the rental lot.
“Automotive paint is a very mature technology”
Perhaps, but they still manage to mess it up on occasion (I’m looking at you Honda), especially with white for some reason. At least this would be a potentially beneficial reason to mess with the formula and screw things up.
I would disagree. Since they had to go water based there have been many issues for many years. Orange peel texture on Fords. Or more significantly the aluminum issues on Stelantis products. Auto paint has had many issues for over 25 years.
Missing bumper – check. Cracked windshield – check. Running on a donut & 3 bald Linglongs – check. Special paint? Woo hoo
Im in Arizona so it would be a nice thing to have here but at the same time I hate white cars and would never buy one. I have owned a black car with a black interior in PHX so I am ok with cooking myself for a preferred spec.
{snark mode on} Even accounting for Nissan reliability it can’t be worse than the 2000s era GM truck/van white paint you constantly see peeling away {snark mode off}
In all seriousness speaking as someone who is actually quite happy with the white paint and light tan cloth interior in his desert exploration vehicle I think there’s something to all this.
I’m sure the body and paint shops will immediately welcome the new paint material and do an excellent job applying it.
Since my son was born in 1994, I have always opted for leather seats because cleaning up the inevitable spills is so much easier.
But they are initially chilly in the cold and hot in the summer. I may well go with cloth upholstery next time. Vinyl was even worse than leather.
Yeah I’ve had two cars with leather seats. My BMW wasn’t too bad as it had been worn in for 15 years or so. My brand-new Nissan Juke was FREEZING in the morning though. Heated seats took way too long to compensate. Cloth all the way for me.
Rich Corinthian Leather is the best…especially The Autopian membership level ha ha
Growing up we had a black Mercedes, my job in summer was to get in it and roll the windows down, this was done by using a crank made of the finest German chromed steel capable of transferring heat to your hand very efficiently. This job was in addition to digging trenches under houses to be able to lift them to level them out.
Cool rental cars.
A white car can be a nice thing as long as we’re not stuck with a black interior.
(and black faux-windows, black roof, black body trim, etc)
Because that would defeat the purpose.
Cool. All the Leaf needs now is NACS, or at the minimum a built in 120v extention cord for charging.
Can it reflect light/heat onto cars around it? …say perhaps this Mitsubishi-shaped hole in space? https://www.theverge.com/tldr/2021/1/16/22233381/vantablack-car-paint-hyper-shift-stars-musou-black
Having now owned a Schwartz 2 (black) BMW 535xi wagon for 7 years, I would absolutely love this. The wagon has so much surface area it gets scorching inside. The gray leather isn’t as hot as black, but still gets hot as hell.
To keep it cool, on any hot day I keep the sunroof and all the windows cracked, and I have a reflective windshield cover/sunshade which keeps the black dash from cooking at a zillion degrees. I haven’t measured the difference over leaving it all closed up, but it is very noticeable.
I would have loved a white one, but when you find a unicorn (manual transmission) you can’t be picky.
What I like about Nissans : The Paint
What I don’t like about (current) Nissans: Everything inside the paint.
I like it, but only if it can make significant improvements to non-white cars. The last thing I need to see is more white cars.
Exactly; if they can’t make this technology work for colors between silver and black on the color wheel, it’s irrelevant.
Fantastic!
How many hours in the sun until the white paint turns yellow? Of course, it will be a different yellow on the bumpers than the steel panels.
This past July, we had a record number of days over 100°, a record number of days over 105°, and a record average high temperature, so a cooler car sounds like a very good thing. Not enough to get me to buy a white one, though.
Is the same thing they use on railroad tracks? (You had an article on the painted tracks recently)
And here I thought the white itself was enough to keep the heat away
Ever since I read that article, I look at railroad tracks when I drive by and shake my head when they aren’t painted white.
Hahah, I’m glad you’re a believer!
I assume they’re just using a regular white paint for that as that’s a big enough leap above black/dark metal.
Awesome job Nissan, now fix your transmissions.
If any company knows about making cars not hot, it’s definitely Nissan.
If the paint keeps the car cool, we don’t have to install radiators anymore!
-Some Nissan executive
I wonder how this paint compares to turning your car into a shiny
mirror.
https://i.ytimg.com/vi/Mn93FkVimuE/maxresdefault.jpg
Have something similar on my tin roof. It really works well.
In a sort of related note: in the wake of what seems to be a run of children left to die in hot cars, those “Baby on Board” suction cup signs have been reappearing here and there. I thought I saw one the other day until I read it it a second time. The message was “Baby on Broil.” I thought it was funny.
My new car reminds me to check the backseat for kids.
I have none, so if that little turd broke in I’d like that warning while I’m still moving so I can boot him out.
I don’t want a white car, but this paint could change my mind.