11mo ago

Nissan develops paint that keeps cars cool in summer heat

www.asahi.com

Nissan develops paint that keeps cars cool in summer heat | The Asahi Shimbun: Breaking News, Japan News and Analysis

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.

170 comments

Nissan also detects you having sex in the car and phones the info home.
- What ahaha.
  
  Their privacy policy includes a provision that they can use the cameras and GPS to infer things such as sexual orientation, so yeah.
- My wife's going to be pissed when she gets that call...
- I’m curious where that’s from? News, or you made up from privacy policy?
  
  Mozilla's analysis if the policies, see my other comment in the thread.
- What kind of garbage article doesn’t include the units!?
  What for? Almost no country uses Fahrenheit.
  
  If that's how scientists did science, we'd have mountains of confusion. "Eh, most people will get it. Good enough."
  Information like this is global. It's a single "C" for clarity. That's not an unreasonable ask.
- Or 53.6 degrees Fahrenheit if you believe whoever wrote the page for Nissan lmao. I guess they just typed it into a converter with no context, and the converter spat out an answer amounting to "if your thermometer says it's 12 degrees C, that would be 53.6 degrees F"... but without that context.
  
  There probably wasn't even anyone who actually wrote it. Fed it into some LLM to generate the page and no one actually edited it to make sure everything made sense
  
  How would you know it’s wrong if you don’t know fahrenheit
- I will not stand for this! Rankine will be the standard! It will confuse and infuriate everyone equally. Truly the fairest of outcomes.
  
  Kelvin and Celsius are the same scale with a different zero point anyway.
- Why would it be anything else?
  It's clearly too low a number to be °K. And since the only two valid units of measurement for temperature are Kelvin and Celsius, it must be °C.
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.
- trick is to paint the windows
  
  Also this is problematic:
  12 degrees cooler
  But by what scale? If it's Flaffenfeit, it's just half an ounce!!!
- 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?
  
  Is ceramic tint different from ordinary tint?
- Could you link one of these? All the ones that I can find say there's quite a bit of a difference
  
  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.)
  
  This is the t-shirt one I remember.
  From
  https://mainichi.jp/english/articles/20230726/p2a/00m/0sc/014000c
  
  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.
- They should install automated blinds like some high end luxury cars have except make them out of that silvery windscreen sunshade stuff.
Nissan invents white paint
- If it's like this stuff then it's more than just white paint.
- Nasa have developed a paint for spacecraft that can be any color including black and still have the properties of white paint. It's only colored in the visible part of the spectrum but allows IR to pass right through.
  Although you do need to paint the vehicle white initially as an undercoat.
I just love how humans will do anything other than actually focus on fixing the problem. Love it.
- I would argue that the new paint could help alleviate the issue, since it would incentivise people to decrease use of the AC. My concern then would be how polluting is the production of the new paint compared to the current version.
  
  My immediate thought was to wonder if this would help give kids who get left in a car by mistake have more of a fighting chance
- So... You want to turn off the sun? This has nothing to do with climate change, the sun hasn't changed intensity in a few 100 years, so sun makes things warm
  
  Lol
- Like reducing the number of cars.
  Ohh too much traffic! 🤔 Let's expand the freeways until you need a freeway to cross other freeways.
  
  Just one more lane will fix traffic bro
- Uhh, what? The problem of things getting hot in the sun?
  
  Blow up the sun. Easy.
  
  Lol
- You're right, running AC more off of internal combustion engines is a better path to the solution.
  
  Lol
They're currently working hard for a way to make it subscription.
Forget Nissan but I'll take the paint.
- Yeah but 350Z tho
  
  I mean, if you're a middle age bro with a retail supervisor job compensating to show off to teen girls, I guess.
  
  There's a very long list of two door sports cars I'd buy instead of one of those bloated excuses.
  
  I had a 370Z. Basically the same chassis with a bigger engine.
  Feels like sitting in a bathtub. It's got a heavy ass flywheel that makes the V6 feel as smooth as a V8, but with predictable effects on responsiveness. You can cut the fly weight in half and it's still perfectly good to run on the street without issues.
  I traded it in for an Miata NC and never looked back. Sure, the Z has more power, but it doesn't make good use of it the way a Miata does.
  
  Yeah but fuck Nissan
Twelve degrees what? A degree Celsius is more than twice a degree in Fahrenheit.
State your units, FFS.
- I will assume celsius since the IR image shows around 45 and 35 degrees in direct sunlight.
- 1kg is more than twice 1lb (2.2lbs) but 1C is only 1.8F
  
  And 1m is only 12 crayons.
- The scientific consensus is that unless otherwise stated it's Celsius.
  In scientific papers you just write 14° you don't need to specify the unit.
  So I'm just going to use that rule and assume Celsius.
Can they develop a paint that reduces the amount of cars? That would be more helpful.
- This might match your criteria:
  
  (Jokes aside, I do agree with your sentiment)
  
  I don't understand, why did you post a random picture of some pavement ?
- 🙄
12 degree °C or °F???
- °C, which is not bad. Official press release (I think): https://global.nissannews.com/en/releases/nissan-trialing-cool-paint-technology
  
  Neat.
Might be the most interesting thing Nissan has developed in two decades.
- They found a very interesting way of selling their hybrid cars as full on EVs where I live. Their e-power stuff are small ICEs working as generators for electric motors that then drive the wheels. Apparently the fact that the wheels get all their power from an electric motor makes it definitely not a hybrid no sir, despite the fact the cars have tiny ass batteries and the single source of power for the whole system is the ICE. Also they somehow have worse fuel efficiency than many contemporary ICEs that cost quite a bit less. I don't understand Nissan.
  
  A few car companies seem to be doing that. Toyota(?) here are advertising their hybrid vehicles as "self-charging electric vehicles" instead of a hybrid, even though there's no way to plug them in and not have them self charge.
  
  Where is this?
diy cooling paint
- That typo reverses the meaning by being one letter off.
  (It had said "diy cooking paint")
  
  Lol
wouldn't this also work on buildings? pavement?
- No, only Nissans. It says right there.
- Probably yes, but it may not actually be doable. Not just because of how much there is to paint, but because the energy doesn't just evaporate. It's got to go somewhere. In this case I'm assuming it's reflected, even if diffused. If everything does this, things that don't (people, cars, pets, etc) will get all that extra energy.
  Wouldn't want to end up in a situation like this: https://www.businessinsider.com/death-ray-skyscraper-is-wreaking-havoc-on-london-for-a-few-totally-insane-reasons-2015-7
  
  It can reflect it out to space. It is possible to make paint the keeps things below ambient. Obviously you're correct, but only for things not facing upward. Upward facing things will bounce the energy back away from Earth.
  https://youtu.be/N3bJnKmeNJY?si=drxjIM8U_MAcQLQH
  
  The amount of folks who have melted their shitty low quality thermoplastic patio furniture with their sliding glass windows will always amuse me, but overall I don't consider IR radiation to be a big problem. Using a bunch of VOCs to paint everything and pollute a city would be though.
  
  Ok, so don't paint it on any concave surfaces. Most buildings have flat or convex surfaces.
- https://youtu.be/N3bJnKmeNJY?si=drxjIM8U_MAcQLQH
  
  great video. Its wild that it is functioning as an IR emitter and just beaming things into space.
- Is metal paint and concrete paint the same thing? I'm not a painter
  
  Ultimately, they can be, but there's lots of differences between them once they reach the bucket you buy. They have different adhesion qualities, but that could be addressed with an appropriate primer. They have different final finish surface requirements, which could be an issue for how the paint works. I remember seeing dragonfly-wing-style paint that was white when viewed perfectly straight buy blue when viewed at any off angle due to a microscopic vertical grid of blue walls. There may also be a required clearcoat component that may not be compatible between the two surfaces. Metal paint is also designed to handle the flex of metal where as concrete paint would barely be concerned about that but possible address crumbling instead.
  Edit: and after reading the article, it's a radiative-cooling paint rather than a reflecting coating. Concrete has a much lower thermal conductivity so this may not be effective in transferring heat out of the concrete.
As someone living in Wisconsin with salty road winters, I'll say that Nissan's reputation is mostly trash here based specifically on their paint
- As someone who used to live there, I'll say that Wisconsin's reputation is mostly trash based specifically on their winters
  
  Also being the Alabama of the North.
Windshield screens are the low-tech but far more effective method of keeping a car's interior cooler, typically by at least 20F when it's really hot out. Slightly inconvenient but unlike this paint, a windshield screen will actually make a difference.
- Mythbusters did an experiment with a black car and a white car hitting in the sun. The black car was 12 degrees Celsius hotter. Claiming that the paint makes no difference is such a weird take. I thought this was common knowledge as well as many people I've met avoid darker colours in summer and such.
  
  Summer was hard on me in my teenage goth years.
  Can't really get many light shades of black.
  
  What's the cost (financial and environmental) of repainting a car vs using a windshield visor that's at least twice as effective at reducing heat? Painting a car with this stuff would cost thousands of dollars compare to $20 for a visor.
  
  Speaking of huge and inconvenient, if you're a cheapskate, just get a car cover. Always helped my motorcycle.
- Wanna know how you're right? Look at the FLIR photo above and note where the heat is at its highest
- I don't care about your cage's interior temperature. Until we can ban cars from cities I'd welcome such paint, because all those shit heaps of cages standing on public space still end up heating up the places around them, further inconveniencing everyone else even more.
  
  Do they? I mean yes, because the ICE engines just constantly dump a ton of heat out, but does a parked car? Is there data on that?
  
  You realize the emissions saved from reduced AC usage would also reduce the heat island effect, right? Sun visors like this are good for public spaces.
  Also, it's more environmentally friendly to have people use visors than repaint their whole car.
  
  Grow up
Why don’t they just make the whole ~~plane~~ planet out of the ~~black box~~ paint.
Anything to not add a cooling system to the ev batteries.
Neat. Now paint the inside.
- so it radiates heat into the vehicle?
  
  How else are you going to entice passengers to take off all their clothes?
can i paint my house with that?
- Nanoparticle roof shingles are a thing and they really work well
- I have a similar coating on my deck in the back yard. I can stand on it barefoot comfortably in the summer which is not possible without the coating.
- There's already a 98% paint, not that cheap last I checked though.
Got in my car after work yesterday and it was 102F inside. It was awful
- Lucky! I've seen 150 here in Louisiana.
  And even higher when I lived in the Mojave desert. Like, if you didn't leave a window cracked there's a real chance your windshield cracks.
  
  Must have had you wishing for a nuclear winter.
  
  I live in Pa, so our weather isn't crazy hot like the south. I can't imagine the weather where you've lived. 85F is my upper limit. Anything over makes me feel like I'm going to die.
Also great for city climate since heated up cars are acting like a heat battery making it significantly slower for a city to cool down once the sun goes away
Ideally there would be no openly parked cars but I guess this is the next best thing
12 degrees? I guess that's cool but still well within egg frying temperature around here.
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How big is the difference between black and silver, metallic and non-metallic paint?
I'm sure those 28% loans will just tack on another 6k in paint. NBD.

170 comments