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'Whitest ever' paint reflects 98% of sunlight

bbc.com

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Re: 'Whitest ever' paint reflects 98% of sunlight

#191

Post by adrian_b »

lm28469 wrote: post #162
abootstrapper wrote: post #146

Earlier quoted context omitted.

I don’t agree with your cynicism. This is a very practical, potentially accessible, inexpensive solution to save literally tons of power. It’s an easy win. Let’s take it and move on to the next area we can make gains in the fight against climate change.

> practical, potentially accessible, inexpensive Painting 1% of the world in white paint is everything but that. It's a cool gadget that will be experimented in a few niche places and quickly and quietly abandoned when real life kicks in. How often will it need to be cleaned ? repainted ? How much will it cost to paint your building's roof, is you building roof even paintable in the first place ? What is the paint ma…

You raise some valid concerns, but this cooling paint has far more chances of being applied in reality than any of the "breakthroughs" you are alluding to.

There are really no disadvantages of using this as a white paint.

Barium sulfate is abundant and the cost of a paint based on this pigment should be very similar to the cost of the current titanium white based paints, once the pigment is produced at industrial scale using the process developed by this team.

There are no environmental concerns, because barium sulfate is as inert as titanium dioxide. Actually there are various living beings which use barium sulfate as a bio-mineral, instead of the more frequently used calcium salts, like in our bones.

So both in cost and environmental properties and also in maintenance properties the proposed white paint should match the currently used titanium white paints, with the difference that it can ensure that any painted surface exposed to solar light is cooled instead of being heated.

Only this will certainly not be enough to save the world, but it will certainly be a useful product.

Re: 'Whitest ever' paint reflects 98% of sunlight

#192

Post by macspoofing »

swsieber wrote: post #165
macspoofing wrote: post #151

Earlier quoted context omitted.

>The reason I want this is because we seem to be swimming in innovation, but nobody to aggregate and make sense of it all, and `join-the-dots` of all this tech so we can make even bigger leaps with it. There is. It's called "the market". Each one of those innovative ideas gets tested by their inventors and backers against real world use-cases. Nothing validates an idea or innovation more than someone writing a check…

> Each one of those innovative ideas On their own though, right? That's not what was being asked. They wanted someway to track things that would work really well together and bring bigger benefits than things could on their own.

>On their own though, right?

Yeah. When I ran a startup, you look for customers, but you also look at partnerships all the time to complement whatever you're doing. Sometimes the partnership finds you, and sometimes you find the partnership. You attend tradeshows and conferences. Sometimes your customers will point you at another company you should work with. That's all part of the market. People behind innovative technologies (inventors, and investors) are constantly looking to find ways for their tech to gain traction.

>They wanted someway to track things that would work really well together and bring bigger benefits than things could on their own.

OP is advocating for a top-down system where they can get a list of innovative technologies and just put them together like lego. It doesn't work that way. It's why a top-down command economy with a central authority doesn't work. There's a lot of trial and error (and failure) that happens at the bottom level and from the top, you just don't know what ultimately is worth expanding effort on and what is a waste of time. Any decision you make about what should go with what is going to be wrong. That's why the market is so powerful for innovation.

Re: 'Whitest ever' paint reflects 98% of sunlight

#194

Post by eatingCake »

mealkh wrote: post #193
tediousdemise wrote: post #79

I bet this would look fantastic mixed with some vantablack, for the greyest grey achievable.

Or the most extreme zebra.

The most jarring Dazzle camouflage[1] imaginable.

1: https://en.wikipedia.org/wiki/Dazzle_camouflage

Re: 'Whitest ever' paint reflects 98% of sunlight

#196

Post by godelski »

eatingCake wrote: post #194
mealkh wrote: post #193

Earlier quoted context omitted.

Or the most extreme zebra.

The most jarring Dazzle camouflage[1] imaginable. 1: https://en.wikipedia.org/wiki/Dazzle_camouflage

Honestly I want to see this. Would your head hurt seeing it in person? Or would your eyes balance it out

Re: 'Whitest ever' paint reflects 98% of sunlight

#197

Post by adrian_b »

coding123 wrote: post #126
malloryerik wrote: post #62

Earlier quoted context omitted.

Your point clearly has merit in many cases, but paint seems almost the epitome of practicality. Assuming that it could be mass producible at a price similar to premium house paints I can't see the problem in bringing this to market. And from the article: > In the US, New York has recently coated more than 10 million sq ft of rooftops white. The state of California has already updated building codes to promote cool ro…

Actually that last bit there seems to be more important to me than the actual tech here. So without this tech people are painting rooftops white. And I'm guessing that's already like a 90% reflectivity? -- So there's really nothing to wait for if you want to cool your house. Just buy... exterior white paint. If you wanted to wait for this specific product, that's fine, but that's almost like waiting for 26% efficient…

The whole point of the discussed paper and of their patent applications is that normal white paint is not good enough to cool something exposed to solar light.

The white-painted object will heat less than when painted in another color, but it will heat anyway.

The white paints described in the paper and in the patent applications, which use either barium sulfate or calcium carbonate instead of the normal titanium white pigment, actually cool the painted object, even in strong solar light.

Re: 'Whitest ever' paint reflects 98% of sunlight

#198

Post by godelski »

layer8 wrote: post #114
tediousdemise wrote: post #79

I bet this would look fantastic mixed with some vantablack, for the greyest grey achievable.

The next step is using the combination in e-ink fashion, so that you can smoothly regulate the thermal profile as needed.

You could probably more easily do this with just a flat surface that you can rotate. Smaller the squares the better uniform distribution you can get but if you don't have those strict requirements then why go super small (e-ink)?
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