SoylentNews is people
SoylentNews
This discussion has been archived.
No new comments can be posted.
'Green' Roofs Slash Energy Use in Summertime Atlanta
|
Log In/Create an Account
| Top
| 8 comments
| Search Discussion
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
(1)
(1)
TAPPING? You POLITICIANS! Don't you realize that the END of the "Wash
Cycle" is a TREASURED MOMENT for most people?!
(Score: -1, Troll) by Ethanol-fueled on Saturday July 14 2018, @08:39PM (3 children)
Perhaps the problem is not only exacerbated by all the concrete, but the color Black, which absorbs more heat.
Yep, Atlanta sure does have a problem with Black, we've all known this since at least Ludacris.
(Score: -1, Troll) by Anonymous Coward on Saturday July 14 2018, @10:17PM
I think the preferred term is afro-American (for adults) and pico-nanos (the metric term for smaller ones).
(Score: 0, Touché) by Anonymous Coward on Sunday July 15 2018, @08:52PM (1 child)
Common misunderstanding. Black doesn't absorb "more heat", it simply absorbs (and radiates!) heat energy at a faster rate than other colors do.
This means that if two objects, one black and one white but otherwise identical, are placed side by side in direct sunlight, the black one will heat up to it's equilibrium temperature (the point at which it is radiating heat as fast as it is absorbing it) much faster than the white one. But here's the kicker: Eventually, the white one will reach the same temperature! And then they'll be sitting there, side by side in the sunlight, both measuring the same by any temperature-measuring device you care to apply other than your hand. Your hand will lie to you, because reasons.
Remove them from the sunlight, and the black one will cool down much faster than the white one. But the white one will cool down eventually, to. And then they'll be the same again.
(Score: 1) by khallow on Monday July 16 2018, @04:50AM
In other words, the near universal counterexample that most of us have experienced to the above fairy tale is ruled out, "because reasons".
In reality, the physics of heat are more complicated than that simple but wrong answer. Sure, a material that absorbs the dominant wavelengths of incoming sunlight (and to our eyes would appear darker) is going to be hotter in sunlight than an identical (that is, all else being equal) material that reflects most of those wavelengths - even in complete vacuum where we can ignore conductive transfer of heat to air. Less energy coming in means a lower temperature (heat radiation increases as temperature increases). It gets more complicated because these surfaces are much lower temperature and thus can have very different radiative properties at the wavelengths at which they radiate most of their energy. Thus, it is possible for a black surface to also be opaque at the temperatures it radiates heat at, meaning less radiation from below the surface of the material while the white colored surface can be transparent at these frequencies, meaning heat is radiated to space from deeper in the object and cooling is faster.
(Score: 4, Informative) by Anonymous Coward on Saturday July 14 2018, @11:48PM (1 child)
France: New Roofs Must be Covered In Plants or Solar Panels [soylentnews.org]
Los Angeles' New Sustainability Plan [soylentnews.org]
-- OriginalOwner_ [soylentnews.org]
(Score: 2) by bzipitidoo on Sunday July 15 2018, @04:18PM
Yeah, the idea of green roofs is not exactly new. Even the present incarnation of fancy, industrial sort of green roofs is at least a decade old.
One issue is the custom of building flat roofs. With a flat roof, takes a lot more support to hold up the soil and foliage. If they used a dome, they could avoid or at least reduce that problem.
(Score: 0) by Anonymous Coward on Sunday July 15 2018, @10:52AM
Came for the sauna, was dissapointed. Way too cold for a sauna.
(Score: 2) by Walzmyn on Wednesday July 18 2018, @04:20PM
That's lovely.
Have they come up with anything for the traffic?