'Whitest ever' paint reflects 98% of sunlight

[Judi Lynn]

By Victoria Gill
Science correspondent, BBC News

Published1 day ago

Scientists in the US have developed a paint significantly "whiter than the whitest paint currently available".

Tests carried out by researchers at Purdue University on their "ultra-white" paint showed it reflected more than 98% of sunlight.

That suggests, the scientists say, that it could help save energy and fight climate change.

Painting "cool roofs" white is an energy-saving approach already being rolled out in some major cities.

Commercially available white paints reflect between 80% and 90% of sunlight, according to lead researcher Prof Xiulin Ruan from Purdue, in West Lafayette, Indiana. "It's a big deal, because every 1% of reflectance you get translates to 10 watts per metre squared less heat from the Sun," he explained.

More:
https://www.bbc.com/news/science-environment-56749105

[calimary]

1. Most interesting! Every little bit.

Every little bit.

[markbark]

2. Whitest white ever?

Minnesota police departments are gonna LOVE it

[Woodwizard]

3. Solar panels cool the roof too.

I have a 20x40' area of solar panels on my shop roof, 9KW worth the airspace between the mounting and roof makes a significant drop in roof temperature. And generates 70 to 80 percent of our power for the shop and house. If I was not using the shop we would generate more power than we use at the house annually.

[lark]

7. I don't think solar panels on rooftops work when you have big trees around the house.

Otherwise we'd install them here. We live in an old growth oak forest and have 5 huge oak trees whose canopy to a more or less degree overhangs the house. We also live in NE FL, so get some strong summer storms (almost always get at least a tropical storm) so parts of those limbs do come down. We get the trees trimmed when big branches start coming over the house, but there are still tons of smaller branches higher up that do come down in a storm. Sadly, we are not in an area where solar panels make sense and I'm not having 5 huge 20-30 ft tall oak trees cut down for that.

[Woodwizard]

10. You are correct.

My shop has really good sun exposure from mid morning until an hour before sunset, when I built it I had solar in mind. It faces south on the long side. I use large home built solar flat plat hot water collector on the south wall to heat the concrete floor in the winter. And a modified pellet stove to burn waste sawdust. No fossil fuel is used to heat the shop at all along with most of the power being from the sun.

[lark]

11. Good planning good results.

Sounds like you have both. Congrats!

[csziggy]

13. Yes, I was told solar panels wouldn't be worth it for my house

I have big live oaks to the southwest, southeast, directly east, northeast, and northwest of the house. To the west there are loblolly pines.

All the live oaks are over fifty years old and several are protected by county ordinance. I planted the loblollys as bare root seedlings just over forty years ago and they are just now getting to their full growth. We did have to cut down some loblollys and a post oak to extend the carport, but there is another stand about fifty feet farther away.

When we originally built the house, solar panels were extremely expensive and not as efficient as now so we built an insulated concrete form (ICF) house which has a tight envelope. With five inches of insulation, it can be days before we realize that our air handler is out. The cost of that was a third of what solar panels would have cost and we didn't have to cut down any trees for it.

[cstanleytech]

15. Trees need water though which is lacking in a number of places.

Of course imo a better option rather than painting a house white would be building a well designed underground home as it can both keep it cool during the summer and warmer when the temperature dips down in the winter and or at night.

[CCExile]

4. Oh, please. Do not tar all cops with the same brush!

[central scrutinizer]

5. If you don't apply it correctly,

It demands to speak with the manager.

[mitch96]

6. I painted my dark roof white and my Florida summer A/C bill dropped a good bit.. nt

[lark]

8. Hmm, good to know.

Did you paint regular roofing shingles and how often do you think it would need to be reapplied? I live in FL too.

[mitch96]

9. Applied to barrel tile reoof. No Idea on repaint time. The only problem was it getting dirty. nt

[csziggy]

14. I put a metal roof on our new house

It is now (with the addition) 3400 sq. ft. and uses less energy than the 1680 sq. ft. house we moved out of. That had a painted metal roof. The new house has a galvanized metal roof so it is silver color and very shiny.

The other things that help are the insulated concrete form (ICF) walls, double glazed windows, and high SEER air handler with a zoned system.

[jeffreyi]

12. Rooftop solar.

Don't f*** up our beautiful deserts.

[GaYellowDawg]

16. How long until Dump has Lard-a-Mango painted in this color?

Jokes aside, cool development.