Roof Paint Blocks 97% of Sunlight and Pulls Water From the Air

Posted2 months agoActive2 months ago

01-_-

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5 comments

newatlas.comResearchstory

calmpositive

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Sustainable TechnologyWater HarvestingCooling Solutions

Key topics

Sustainable Technology

Water Harvesting

Cooling Solutions

A new nano-engineered polymer coating can reflect 97% of sunlight and collect water from the air, with potential applications in cooling buildings and addressing water scarcity. Commenters discuss the technology's potential and explore possible DIY alternatives.

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01Story posted
Nov 3, 2025 at 3:48 PM EST
2 months ago
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Nov 3, 2025 at 4:01 PM EST
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Nov 3, 2025 at 4:52 PM EST
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Discussion (5 comments)

Showing 5 comments

bell-cot

2 months ago

2 replies

> Researchers at the University of Sydney and commercial start-up Dewpoint Innovations have created a nano-engineered polymer coating that not only reflects up to 97% of the sun's rays, but also passively collects water. In tests, it was able to keep indoors up to 6 °C (~11 °F) cooler than the air outside.

So "blocks" is a poor word choice - tarpaper will block 97%+ of light.

I see nothing about the cost / durability / toxicity of the new paint-ish coating. Hopefully that's "low" / "very" / "non-".

allears

2 months ago

1 reply

They did say that the material didn't degrade over the course of their testing, but of course that's only a year or so.

bell-cot

2 months ago

> the coating withstood the challenging test of the harsh Australian sun, and showed no signs of degradation over the six months.

Real-world optimal would be 25+ years - in environments with acid rain, bat/bird droppings, hailstones, heavy smog, ice dams, 65° C summers, and several other sorts of hazards.

(Yes, that's a ridiculously big ask. OTOH, the planet we're stuck on is starting to char. And workable Planet B's are looking extremely scarce):

tocs3

2 months ago

As far as the "non-" you might look at

From https://en.wikipedia.org/wiki/Polyvinylidene_fluoride#Safety...

"PVDF is widely considered safe and ubiquitous used for water treatment,[24] the food industry, and biocompatible devices like hernia meshes or internal devices.">

tocs3

2 months ago

I do not have any polyvinylidene fluoride-co-hexafluoropropene (PVDF-HFP) but I wonder if there is a similar DIY option. It sounds like it uses little bubbles in the paint to reflect the sunlight. I would really like something like this here in Texas. It is getting dryer and I worry about our well.

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ID: 45804244Type: storyLast synced: 11/17/2025, 7:50:56 AM

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