White Washed: Could a Coat of Paint Fight Global Warming?

[bananas]

http://blogs.wsj.com/environmentalcapital/2008/09/10/white-washed-could-a-coat-of-paint-fight-global-warming/

September 10, 2008, 1:00 pm
White Washed: Could a Coat of Paint Fight Global Warming?
Posted by Keith Johnson

There’s a good reason the famous “White Towns” of Andalusia, in southern Spain, are all white-washed. The sun is hot in Andalusia, and white paint reflects the heat, keeping interiors cool.

Could that age-old Mediterranean remedy help fight global warming? Increasingly, a lot of scientists think it could, if big chunks of the earth’s urban rooftops and paved surfaces were covered with light colors that reflected—rather than absorbed—the sun’s rays.

Researchers at the Lawrence Berkely National Laboratory in California just presented new work showing that the heat savings from having reflective roofs and pavements could offset huge amounts of greenhouse-gas emissions. In addition to cutting air-conditioning bills, that could help buy time for the rest of the economy to retool to cleaner forms of energy. From the L.A. Times:

Globally, roofs account for 25% of the surface of most cities, and pavement accounts for about 35%. If all were switched to reflective material in 100 major urban areas, it would offset 44 metric gigatons of greenhouse gases, which have been trapping heat in the atmosphere and altering the climate on a potentially dangerous scale. That is more than all the countries on Earth emit in a single year. And, with global climate negotiators focused on limiting a rapid increase in emissions, installing cool roofs and pavements would offset more than 10 years of emissions growth, even without slashing industrial pollution.

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[kristopher]

1. I don't buy it; here's what I wrote earlier on GD.

The average area of the Arctic ice in summer is about 2.5 million square miles, and during the winter about 6 million square miles. We soon expect the summer ice to disappear. This is of great concern to climatologists because it changes the reflectivity (albedo) of the Earth.

There are 83 million residential buildings in the US. Using an average of 1000 square feet per unit (it is actually more) that makes 83 billion square feet of RESIDENTIAL roofing.

So if we read this article, it sounds like we might be onto something to mitigate the loss of Arctic ice, right?

Not so fast.

83,000,000,000 square feet only equals about 3,000 square miles.

Now the homes are much further south than the arctic ice so there would be a large difference in how much energy is reflected per square mile, but it isn't going to even come close to equating the amount of energy reflected by the ice.

I replaced my shingle roof with light (beige) colored steel roofing and it makes a great deal of difference in the summer; I highly recommend using a light colored roof. As far as GW goes it probably will help, however, don't fool yourself into thinking that is going to be a significant offset to the change in albedo due to loss of Arctic ice.

[Merlot]

2. So now the gov't gonna tell me what color my roof has to be?

Brilliant solution. And I can just hear the stupid deniers wailing.

[The Croquist]

3. As a stupid denier

I put white shingles on my roof 15 years ago.

[Javaman]

5. You deny that global warming is happening or man made? nt

[The Croquist]

13. I think the earth has warmed in the last 100 years but I don't

think that man has contributed a significant amount.

[kristopher]

15. Are you aware of the well documented disinformation campaign executed by Exxon? nt

[kristopher]

4. Why not.

You're required to have a flushing toilet, electricity, etc.

Why should dealing with an urgent environmental crisis be less important that proper disposal of waste?

Screw the deniers; they're Darwin award material.

[LiberalEsto]

6. Here's some roof paint info

http://hytechsales.com/roofcoatings.html


I'm using their ceramic-based paint additive to see if it reduces heating costs. So far I've done two bedroom walls and am about to start on the exterior foundation of our house. I would love to try their roof coating but can't do the job myself because I'm afraid of heights.

[phantom power]

7. I'd be interested in a followup on the ceramic paint additive...

I recall somebody posting about that a couple years ago here. About a month after we painted our house, naturally. I'd use it exterior, here in the desert.

[LiberalEsto]

9. I'll post when the heating season starts

So far I've noticed:

1) The ceramic stuff is incredibly easy to mix into regular paint and apply.

2) It gives the walls a "sueded" texture which is nice.

3) It's cut down on sound from the outside. Apparently it can also be used in apartments to muffle noise from adjoining apartments.


So far I've done my two interior bedroom walls that have exterior walls behind them.

[phantom power]

10. Interesting that a thin layer gives a measurable sound reduction.

That's probably also a good omen for heat insulation.

[LiberalEsto]

14. NASA developed these tiny ceramic balls

and Hy-Tech is marketing them commercially as a paint additive. Did you check the link to their website?

This is from another website:
http://www.sti.nasa.gov/tto/spinoff2003/er_4.html

"As a manufacturer and marketer of thermal solutions for residential, commercial, and industrial applications, Hy-Tech Thermal Solutions attributes its success to the high performance insulating ceramic microsphere originally developed from NASA thermal research at Ames Research Center. Shaped like a hollow ball so small that it looks as if it is a single grain of flour to the naked eye (slightly thicker than a human hair), the microsphere is noncombustible and fairly chemical-resistant, and has a wall thickness about 1/10 of the sphere diameter, a compressive strength of about 4,000 pounds per square inch, and a softening point of about 1,800 ºC.

Hy-Tech Thermal Solutions improved upon these properties by removing all of the gas inside and creating a vacuum. In effect, a “mini thermos bottle” is produced, acting as a barrier to heat by reflecting it away from the protected surface. When these microspheres are combined with other materials, they enhance the thermal resistance of those materials."

[meow mix]

8. but how does this reduce carbon emissions?

just wondering..

[kristopher]

11. Actually it is mostly CO2e

That small e stands for equivalent. It doesn't reduce CO2, it negates some of the warming by increasing the reflectivity of the planet. These types of inputs to the balance equation have been quantified and are scaled on a CO2e scale.

[XemaSab]

12. For one, it probably cuts down on air conditioning costs in cities

but I think it has more to do with the amount of heat reradiated to the atmosphere. :shrug: