Comment by lm28469 | Hacker News Reader

Comment by lm28469 | Hacker News Reader

Parent Full thread

> 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 made of exactly ? Is it going to leak in the environment ? How much energy/resources are needed to make/transport it ? What impacts does it have on a multi storey building ?

Time will tell but I bet it's going to end up in the same bin as the "massive lithium battery breakthrough" news. /reminder 10 years

They've been talking about this since at least 2005 by the way. Good old hype cycle in effect:

https://www.osti.gov/servlets/purl/10172670

https://www.bbc.com/news/10333304

http://archive.iwlearn.net/unep.org/paint4planet/default.htm

https://www.theguardian.com/environment/2009/jan/16/white-pa...

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.

Presumably most buildings are painted. My house for example. If painting it white saves %10 of my energy costs in the summer, how is that anything but a net positive? BTW, I’m in the market for a new roof. I’m going white painted metal.

Are double pane windows, solar panels, and insulation also gadgetry hype?

Reply on news.ycombinator.com