Air Conditioning isn't free... but we're close.

Today we show you how to construct a liquid panel with custom specialty paint that when placed outside, cools down to a lower temperature than the ambient temperature.

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[Nighthawkinlight]

Yes! Great to see you working on this also. Your test setup is pretty much what I came up with for a future video, but you did a much better job of it. I've been working on a variety of coating methods for comparison. In recent experiments I found that barium sulfate and calcium carbonate pigments have near equal performance if used in the snow scattering acrylic base from my earlier video, with barium only slightly pulling ahead. I hit about 4C below ambient with the coatings facing directly toward the sun. I hope my experiments past and future help you develop this into a practical diy solution for everyone.

[joshuagibson]

You're a good dude. As well as your son. I appreciate the quality of the presentation as well as the topic itself. A 20 minute video takes many hours to put together. I appreciate the effort.

[kvnivn]

I’m fascinated by the potential of this. I live in a desert and during the summer months, our electricity bills skyrocket; if we could make passive cooling work for residential housing, it would be revolutionary. I’ll be studying this further, thank you so much for sharing your process and discoveries!

[gtmunch]

Your specialized coating is not the only cooling technology in this video. That Members Only jacket instantly makes you cool.

[ThisIsNotWhatItLooksLik]

No wasted words in explanations, straight to the point. As if my brain woke up from all the fluff trash I have been watching.

[santoshr]

This is ONE OF THE BEST channel I have ever seen for CORE TECH content. I dont know what is your day job, but someone giving away such info is just amazing.
I live in 38 - 48 degree area with 60-90% humidity 8 months of the year. I have been looking for passive cooling for so long. Never found such deep tech content.
What a time to be alive.

[skateerdud]

It is so insanely refreshing to see a video from someone on YouTube that not only knows what they're talking about, but can explain it in detail and doesn't shy from difficult topics. Finally a YouTuber that doesn't make me feel pandered to with no content that feels dumbed down. Overall very fantastic, this is currently my favorite channel!

[ChannelSho]

I'm not even 5 minutes in and I learned a ton. This guy really knows how to explain things in a clear and concise manner.

[joeflosion]

Hey again Mr Ingredients. I've made this comment before but I feel its important so I want to say again, it is so cool that you do these projects with your son and how you nearly always say "we" instead of "I" when explaining the processes. My parents live 1100 miles away from me now, and I really miss doing projects and experiments with my dad. Keep these awesome videos coming!

[singalongwrudy]

Planted trees ALL around my house in '87. Now I have shade ALL day.

[jacobbaumgardner]

My grandfather built their house with passive solar in mind. A 4ft deep space sits under the house, with river stone as its bed. The entire front face of the house has a sun space going up over 2 stories. This allows for airflow from underneath the house to pull heat from the rest of the house forward.

It’s pretty effective, though you have to work to ensure that cool nights flow into the house and then seal it up during the day, at least in heatwaves like the one we’re in now. It does have its limits, as the 100+ F temperatures we’re experiencing now mean the upper floors get quite warm, but we have been able to keep the downstairs between 68-74F throughout the day.

With such a house design, even small AC input would make a large difference, minimizing energy consumption.

[Jay_TheCat]

I am so glad that you are back and doing videos after the accident, i find all of your videos very interesting! I hope you are fully recovered and keep up the good work!

[R.A.M_]

Man, the content you guys produce here is just grade A (as in awesome) stuff. Your methods of implementation are always explained in such a pristine way.

[shutton]

You are an excellent lecturer. It is so easy to follow along with your lesson. It is the cadence and the tempo and the tone of voice that you use that carries so well.

[thromboid]

I've been playing with infrared thermometers and thermal imaging cameras lately, so it's great to have your explanations of some of these phenomena. In particular I've noted:
- the coldness of the sky (which often measures -40 to -60 degC)
- the opacity of glass to IR
- the transparency of certain plastics to IR
- the high reflectivity of certain rocks and ceramics
- the way a dull (e.g. galvanised or brushed) metal surface acts as a much clearer mirror in the infrared (presumably the longer wavelengths in IR are less affected by the surface roughness)
- the way splashes of water stand out as colder than their environment, and remain colder as they evaporate, eventually leaving the surface still cooler than the surroundings

[jessejuliano]

Mate, you are truly a diamond on here. Its amazing what you do, and I am consistently blown away at the progress you are making. You are changing the world man.

[machinemaker]

Thank you for sharing this so far. Please remember to do the follow-up video. I very much want to learn about the daytime efficiency and the coating. I'm in Florida, and the summers are brutal here. Any improvements that I can make would be very much appreciated.

[Max_Marz]

"Air is actually a great insulator when it isnt moving, its the air bubbles in the foam that do the insulation not the foam itself"

You unlocked a pretty deep intuition with that one in me, thank sir, may I have another.

[anomuumit]

The Royal Institution had a surprisingly interesting lecture here on Youtube on the subject of air conditioning. The lecture can be found under the name "The Physics of Hot Air - with Shaun Fitzgerald". It really opened my eyes to how complicated it is to design a building with good natural air flow and how much power savings there could be had if the air would naturally flow through the structure instead of forcing it through with machinery.

[HeyChickens]

I love passive cooling experiments! Thanks for bringing this to the fore! I know you weren't able to mention every single detail, but nevertheless it should be noted that on the vast majority of nights when cooling is most needed there will also be high humidity, which means condensation. Any condensation that forms on this special coating will temporarily nullify its special properties, since the water droplets will become the new radiating surface. Therefore it is crucial to eliminate the potential for condensation to form on the coating. This can be done by completely sealing off the area between the plastic wrap and the coating, and only allowing outside air to equalize any pressure difference after entering that area through a port containing a reservoir of a strong desiccant material. The desiccant would obviously have to be maintained by periodic regeneration. All very doable things. I imagine that the special coating would be a material that has a very narrow emissivity band exactly coinciding with the transparency window of the atmosphere. I just recently read a paper about some extensive research and experimenting that was done to accomplish this. They were able to consistently achieve (when clouds were not a major issue) much colder than ambient temperatures, I want to say somewhere around 20 degrees C colder or more. In fact, they found that this passive cooling actually works best during the day (obviously due to the higher temperature difference between earth and sky during the day). Now the caveat is that these very large temperature differences below ambient can only be maintained when as much heat load as possible is eliminated from the radiator. So if you actually want to tap into that potential and use it to cool something, that sub-ambient difference will be significantly less. So there would be a sweet spot where you would achieve maximum benefit from this setup. If you radiate at near ambient temperatures, your heat dissipating capacity will be the highest because of Plank's law. But your cooling fluid would only be cooled to ambient temperatures, which would be almost useless. If you try to achieve max temperature differential, your radiator will be super chilled, meaning you will be removing very little heat. One way to ensure max efficiency of this setup would be to do it in stages. The first stage of sub-cooling could be perhaps a much larger panel set up all around the super-chill panel in the middle, and this pre-chill panel would not need tall aluminum blinders on the sides to cut out the incoming radiation from trees and buildings and such. It would take advantage of a greater percentage of the open sky, thereby dissipating more total heat, but would only go a little bit below ambient. Then the fluid would enter the center panel setup (the super-chiller) which has taller aluminum blinders, where it would do the limbo and see just how low it can go.