I Made The World's First Self-Cooling Clothes

追加: 2026-06-07

[00:00:00]This is the world's coldest paint. It has the ability to keep an object cooler than the shade even when it's in direct sunlight without using any energy in the process. So, let's measure the shade under this plant. [music] Okay, we get about 85°. But, now let's see our panel that I painted with the cryo paint in direct sunlight.

[00:00:19]And we get like 83°.

[00:00:21]So, sitting out in the blazing sun is cooler than the shade.

[00:00:25]But, a similarly colored white panel is 117° and a black panel is 175°.

[00:00:32][music] But, how is this possible?

[00:00:34]Where's the heat going? Well, in this video, I'm going to teach you how to use the sky as a giant heat sink and then even apply it to clothing to see if I can make the world's coolest clothes, literally.

[00:00:47]I'm hot and my chickens are hot, too.

[00:00:49]But, what if I told you there's something in the middle of a 100° summer day that's well below freezing that can be used to cool you down for free? Yes, that's right. High above us, the upper atmosphere is literally freezing cold.

[00:01:02]In fact, you can see how warm the clouds are in comparison.

[00:01:06]Clouds are like a nice warm blanket over everything.

[00:01:09]So, if we want to radiate the maximum amount of heat, we don't want clouds. We want the open blue sky that we can use as a giant cold heat sink. Remember that there are three ways in which something can exchange heat with its environment.

[00:01:22]The first way is through touch. If something is physically connected to something else, the heat energy is going to spread out from the hot thing to the colder thing. This is called conduction.

[00:01:32]Now, the close cousin of conduction is called convection. This is basically conduction, but you keep refreshing the thing that the object is touching. And there's also a third mechanism of heat transfer that sometimes gets overlooked, and this is radiation.

[00:01:46]For me, radiation is the most magical of the heat transfer mechanisms. The reason is because you can't stop it from happening. Even if your objects are miles away or even in the vacuum of space, you will always be losing or gaining heat through radiation.

[00:02:01]Radiation is the heat you feel from a fire that's instant and travels at the speed of light. So, every object, including you, is constantly emitting radiation. And since emitting radiation means losing energy, that means that everything is constantly cooling down, just throwing its energy out everywhere around it at the speed of light. But, there's this rule called Kirchhoff's law that says an object emits radiation just as well as it absorbs radiation at that same wavelength. So, a good emitter is also a good absorber. So, you can't just make an object that's really good at emitting radiation without making it really good at absorbing it, as well.

[00:02:37]But, there's a way to kind of cheat the system. If you just have your object be a good emitter in a frequency range where there's very little incoming radiation, then you can have a one-way valve that emits radiation, but there's nothing to absorb. And that's what makes this paint so special. It's designed to only emit and absorb radiation in the range of wavelengths called the atmospheric window. This is the range where the sky produces almost no radiation. So, the paint can just send its radiation out into the sky and almost nothing returns. Okay, so let's look at these on the IR camera.

[00:03:11]We can see there's a huge difference.

[00:03:13]The black panel is extremely hot, around 170° F. While the white-colored one is still hot, as well, it's near about 120° F.

[00:03:25]But, our cryo-painted panel is only about 85°.

[00:03:29]That's insane.

[00:03:31]That's way cooler than I would have expected. I can tell just by touching it the difference. I literally get burned trying to move the black panel, but with the cryo-painted one, it's almost cool to the touch. Now, it's clear that the panels themselves stay much cooler with this paint. But, I want to see how much of a difference it makes as a a panel.

[00:03:51]So, in order to test this, I built a small insulated room where I can use these panels on the roof and see if I can tell a difference. Okay, let's try the black one first. So, the difference in the actual roof temperature when we're inside, just measuring the air, I'm 92° for the thermal couple that's up here, and 87° for the thermal couple that's a little bit lower, kind of chest level.

[00:04:17]But, I don't think these thermal couples are doing well at conveying the actual temperature I feel. Cuz it feels very hot under here, just from the radiation from the ceiling panel. So, even though the air isn't heating up that much, I'm heating up standing under it due to its hotter temperature radiating to my skin.

[00:04:34]Now, let's try the cryo painted panel.

[00:04:37]>> [music] >> So, this one definitely feels different.

[00:04:39]The air temperature is only slightly different. It's lower by like 5°. But, as far as how it feels, it feels much cooler because I don't have this radiator heater above me radiating heat to my skin. [music] So, it does make a difference. It's not as extreme of a difference compared to the surface temperature of the panels in the sun, but it is a noticeable difference. So, if my chickens produce enough eggs, they can save up for more cryo paint for their roof. But, now the important question, what about me? Well, I know the paint works for the panels, but could it work for clothing as well?

[00:05:12]Well, let's see about that. I'm going to paint it on my clothes and see if it actually keeps me noticeably cooler with the cryo paint. Okay, I think this actually does make a difference. So, this actually works way better than I thought it was going to. It's about 90° out here, and I don't feel hot at all, like in the slightest amount. It would seem like if I have my hood on and everything that it's going to be really hot in this jacket, but I really don't feel hot at all. It's kind of crazy. So, why has nobody turned this into a product yet? Because this is awesome.

[00:05:43]Look at the infrared view. You can see how much cooler my clothing is compared to the background objects in the sun.

[00:05:49]So, me and my chickens are going to stay cool this summer. And thanks for watching another episode of The Action Lab. I hope you learned something. If you haven't subscribed to my channel yet, remember to hit that subscribe button and we'll see you next time.