this post was submitted on 28 Aug 2024
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657
Nissan develops paint that keeps cars cool in summer heat (www.asahi.com)
submitted 2 months ago by [email protected] to c/[email protected]
247 comments fedilink hide all child comments
 

Nissan Motor Co. said it has developed a new type of paint that significantly reduces the temperature inside vehicles parked in direct sunlight.

The surface of a car coated with the innovative material remains up to 12 degrees cooler than that of a vehicle with standard paint, tests showed.

The company said the coating material can help rein in the temperature rise not only on the car's body but also in the vehicle when exposed to direct sunlight.

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[–] [email protected] 33 points 2 months ago (5 children)

I seriously doubt that, tests have been performed comparing black and white painted cars, and the difference was insignificant. The heat buildup in a car is due to the the sunlight entering through the windows.

[–] [email protected] 36 points 2 months ago (1 children)

trick is to paint the windows

[–] [email protected] 14 points 2 months ago* (last edited 2 months ago) (1 children)

Also this is problematic:

12 degrees cooler

But by what scale? If it's Flaffenfeit, it's just half an ounce!!!

[–] [email protected] 7 points 2 months ago (1 children)

And an ounce is nowhere close to a decimeter!

[–] [email protected] 7 points 2 months ago (1 children)

I bet Kelvin couldn't agree more. But to be fair, he started a bit on the negative side. And called everything above that plus.

[–] [email protected] 3 points 2 months ago (2 children)

A bushel of paint should be enough to cover 12 roods.

[–] [email protected] 3 points 2 months ago

Dammit, I needed 5.5 qt paint to cover one parking spot

[–] [email protected] 1 points 2 months ago

Our European friends are going to need you to convert that to kilometers.

[–] [email protected] 30 points 2 months ago (1 children)

To add to your comment, ceramic window tint is a night and day difference. My steering wheel, shifter, and all couldn't be touched after work. I wore driving gloves to get home. With the tint there slightly warm and the AC doesn't take half the drive to catch up, the car is cool by the first stop light.

Maybe they should sell cars with that by default instead?

[–] [email protected] 9 points 2 months ago (1 children)

Is ceramic tint different from ordinary tint?

[–] [email protected] 11 points 2 months ago* (last edited 2 months ago)

Yes. It contains ceramic nano particles that reflect UV without interfering with visibility.

edit: I meant IR. But it reflects both.

[–] [email protected] 8 points 2 months ago (3 children)

Could you link one of these? All the ones that I can find say there's quite a bit of a difference

[–] [email protected] 7 points 2 months ago* (last edited 2 months ago) (1 children)

OK I'll link the danish test, this test is done with 2 cars that are identical, except for the color of the paint:

https://livsstil.tv2.dk/2018-05-24-bliver-en-sort-bil-varmere-i-solen-end-en-hvid-tv-2-har-lavet-testen

Konklusionen er altså, at den sorte bil ikke varmes mærkbart mere op end den hvide.

Translation:
The conclusion is that the black car does not heat up noticeably more in the sun than the white.

So it does a little bit that you can measure, but not enough to really make a difference.

Det skyldes ifølge Christian Bahl, seniorforsker hos DTU Energi, at bilerne opvarmes gennem ruderne.

According to Christian Bahl senior researcher at DTU energy, that is because the cars are heated through the windows.
(DTU is a well recognized institution for scientific research in Denmark.)

[–] [email protected] 3 points 2 months ago

Maybe the fact that the experiment was done when outside were only 20-22 degrees made the difference less noticeable? Otherwise I can't explain why all the other tests I've found said the difference was 5-10+ degrees.

[–] [email protected] 1 points 2 months ago* (last edited 2 months ago) (1 children)

Sorry can't find it, all I can find in english are some where the data isn't clear.
If a white car has brighter interior it will stay slightly cooler, I cannot find a test where everything is the same except the color of the car.
What I can say however, is that the test I saw was performed in Denmark. It's possible countries with hotter climates may observe some difference?

Obviously the main source of heat is what enters through the windows, and how much is reflected out again does have an influence.,

If a white car has white seats and interior, they will obviously not heat as much as black seats and interior.

The white color on the exterior will also reflect more light into the car, except maybe at noon.

Edit PS:
I linked the danish test in a new response.

[–] [email protected] 1 points 2 months ago (1 children)

Obviously the main source of heat is what enters through the windows, and how much is reflected out again does have an influence.,

A lot of things seem obvious but turn out not to be, or not as much as I've first thought. Hence the usefulness of data and studies rather than mere reasoning.

[–] [email protected] 1 points 2 months ago

If you saw my other post, this is absolutely confirmed by data.

[–] [email protected] -2 points 2 months ago

They should install automated blinds like some high end luxury cars have except make them out of that silvery windscreen sunshade stuff.