Researchers develop super-thin coating that could help keep buildings cool during the summer

[Shawn Knight]

Keeping a large building cool during hot summer months is no easy task. In addition to soaking up warmth from outside, building dwellers also have to contend with heat generated from within. It’s a combination that often forces air conditioning units to work overtime.

Researchers from Stanford University have come up with a new solution to help keep occupants from roasting during the summer – an extremely thin coating that works by reflecting up to 97 percent of sunlight while simultaneously radiating heat from inside the building.

It’s a technique that the researchers have dubbed photonic radiative cooling.

The material they created consists of eight layers and is collectively just 1.8 micros thick (that’s thinner than the thinnest sheet of aluminum foil). Specifically, it’s made of seven layers of silicon dioxide and hafnium oxide on top of a thin layer of silver.

The technology certainly sounds promising although it doesn’t appear to be close to commercial use just yet.

The first problem is figuring out how to transfer a building’s internal heat to the exterior coating. Once it gets there, the material can expel it but getting it there is the first hurdle. 

The researchers’ second issue is scaling. Their existing prototype is the size of a personal pizza – or in other words, nowhere near as large as it needs to be to do its job efficiently in a real-world application. The good news here is that existing production facilities are capable of scaling it up to desired sizes.

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https://www.techspot.com/news/59008-researchers-develop-super-thin-coating-could-help-keep.html

 

[Uncle Al]

Sounds promising but we have seen similar products in the past (remember the old solar reflecting insulation sheets from the 80's). How it will be applied will also be a determining factor in it's viability. Now, if you could somehow combine this technology with the newer thin film solar panels that are next generation, you could have a remarkable product. A 95% efficiency in that kind of panel would make it highly attractive for even the most modest homeowner to install.

 

[Misagt]

I work in the construction field there are a number of products like this on the market currently. Not quite as efficient but still do a good job of reflecting Infrared and reducing heat transfer. Also I would have a concern about ending up with another giant magnifying glass. Like that building in London that torched the street very noon.

 

[risc32]

Sounds promising but we have seen similar products in the past (remember the old solar reflecting insulation sheets from the 80's). How it will be applied will also be a determining factor in it's viability. Now, if you could somehow combine this technology with the newer thin film solar panels that are next generation, you could have a remarkable product. A 95% efficiency in that kind of panel would make it highly attractive for even the most modest homeowner to install.

they still use that produc(alum faced foamboard/or what is basically giant alum foil as a radiant heat reflector)t. it's good, it just needs to understood. I'm in the building industry and most builders don't care to get there heads around it. I don't blame them, the industry is always promising breakthru products and they almost always fail to outperform the old tried and true stuff. Anyway, this thing here claims to go a step further and have the ability to radiant a buildings indoor heat outward. well, cool, but that's just going to need a total rethink of some major building parts. the building industry isn't yet 100% or what to do with things like humidity, so this won't be figured out overnight.
as for this coating on solar panels, I guess you mean as a way to reduce their solar heat gain and thus lower their temp. I hear that those high temps aren't good for them or their efficient operation. plus it would be installed at the factory in ideal conditions so that might be a good.