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Old 20th March 2017, 08:26 PM   #2481
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Originally Posted by weltersys View Post
Too bad this "breakthrough" gets rid of 93 watts per square meter, while good old Sol delivers 1000 watts per square meter.

Like Gus Welter said: "The only problem with free energy is it costs so much".

Art
That's certainly true, but note that they said the absorption was 4%, so back of the envelope say that's roughly 40watts of sunlight absorbed. The rest gets reflected.

Now they say "When backed with a silver coating, the metamaterial shows a noontime radiative cooling power of 93 watts per square meter under direct sunshine." I think that's ambiguous and can't tell if that's 93watts net cooling or just 93 watts radiated, but either way you're somewhere between 53 and 93 watts of net cooling effect per square meter. It won't displace your AC unit any time soon, but it's still impressive and potentially very useful.
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Old 20th March 2017, 11:25 PM   #2482
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Quote:
Originally Posted by zettairyouiki View Post
That's certainly true, but note that they said the absorption was 4%, so back of the envelope say that's roughly 40watts of sunlight absorbed. The rest gets reflected.

Now they say "When backed with a silver coating, the metamaterial shows a noontime radiative cooling power of 93 watts per square meter under direct sunshine." I think that's ambiguous and can't tell if that's 93watts net cooling or just 93 watts radiated, but either way you're somewhere between 53 and 93 watts of net cooling effect per square meter. It won't displace your AC unit any time soon, but it's still impressive and potentially very useful.
If true, the silver coated (sterling, or Mylar?) metamaterial could easily replace my 3 ton 12 SEER (36,000 BTU, 3000 watt) AC unit with only 56.6 square meters (24.45 by 24.45 feet) of the unobtanium at 53 watts of net cooling.

That said, at 93 watts per square meter, it is less "bang for the real estate" than solar panels, so we will have to see what the real market price turns out to be, if it really makes it to market.

Art
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Old 21st March 2017, 11:49 PM   #2483
Pabesco is offline Pabesco  Bahamas
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hi guys, i want to build a few tops for my system that will also compliment the th18s i have, any suggestions?
i use my th18s only occasionally but the other parts of the system get used a lot and i only have the jbell tops i built a few years ago to go with my ths.
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Old 21st March 2017, 11:51 PM   #2484
Pabesco is offline Pabesco  Bahamas
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also can someone please remind me how to post pics
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Old 21st March 2017, 11:52 PM   #2485
djk is offline djk
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Old 22nd March 2017, 12:08 AM   #2486
Pabesco is offline Pabesco  Bahamas
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I'm not sure what you mean.
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Old 22nd March 2017, 12:32 AM   #2487
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Originally Posted by Pabesco View Post
I'm not sure what you mean.
You don't need to host them on an external site in order to post images here. When creating a message, simply look under the "Additional Options" section and click on the "Manage Attachments" button. The rest should be self-explanatory.
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Old 22nd March 2017, 12:51 AM   #2488
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Originally Posted by Pabesco View Post
hi guys, i want to build a few tops for my system that will also compliment the th18s i have, any suggestions?
i use my th18s only occasionally but the other parts of the system get used a lot and i only have the jbell tops i built a few years ago to go with my ths.
You should give more information on what kind of tops you want to use. How many people are you covering/how loud do you want to go? What kind of dispersion angles do you want to achieve? How many tops per side do you want to run? How heavy or how large can the cabinet be? What kind of budget for drivers do you have?
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Old 22nd March 2017, 01:01 AM   #2489
Pabesco is offline Pabesco  Bahamas
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Thank you
For the info about posting pics
Also thank you for the info I missed out about the tops. I will put that info in in about an hour. Just have to consider a few of the points you made.
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Old 22nd March 2017, 03:34 AM   #2490
Pabesco is offline Pabesco  Bahamas
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I would be looking to cover about 100 to 200 people at any given time and I would like to be using between two and three per side.
I need them to be really loud and cover a good area. The budget for the drivers is pretty good but nothing too expensive and I need these to be no wider that 24 inches and no deeper that 24 inches.
I hope I answered the questions well enough for you to suggest some options.
Thank you all once again.
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