<html><body><span style="font-family:Verdana; color:#000000; font-size:10pt;"><div>I was once told that the best collector used black chrome plated on bright nickel. </div>
<div>This combination absorbs heat well, with the advantage of not letting the heat back out. </div>
<div>Sort of a thermal "diode" of sorts.</div>
<div>I have no data, but I believe "good" collectors radiate less than they collect.</div>
<div> </div>
<div>Mark</div>
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<div >-------- Original Message --------<BR>Subject: Re: [RE-wrenches] solar hot water nighttime recirc<BR>From: "Carl Emerson" <freepower@freepower.co.nz><BR>Date: Fri, December 18, 2009 10:04 pm<BR>To: "'RE-wrenches'" <re-wrenches@lists.re-wrenches.org><BR><BR>
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<div><FONT face=Arial color=blue size=3><SPAN style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: Arial">Hi there gang,</SPAN></FONT></div>
<div><FONT face=Arial color=blue size=3><SPAN style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: Arial"> </SPAN></FONT></div>
<div><FONT face=Arial color=blue size=3><SPAN style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: Arial">Just to say that IMHO solar thermal panels will radiate quite a bit less than they collect, someone must have some data on this ??</SPAN></FONT></div>
<div><FONT face=Arial color=blue size=3><SPAN style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: Arial"> </SPAN></FONT></div>
<div><FONT face=Arial color=blue size=3><SPAN style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: Arial">Have a great Christmas.</SPAN></FONT></div>
<div><FONT face=Arial color=blue size=3><SPAN style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: Arial"> </SPAN></FONT></div>
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<div><FONT face=Arial color=blue size=3><SPAN lang=EN-NZ style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: Arial">Carl Emerson</SPAN></FONT></div>
<div><FONT face=Arial color=blue size=3><SPAN lang=EN-NZ style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: Arial">Free Power Ltd.</SPAN></FONT></div>
<div><FONT face=Arial color=blue size=3><SPAN lang=EN-NZ style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: Arial">Web www.freepower.co.nz</SPAN></FONT></div></DIV>
<div><FONT face=Arial color=blue size=3><SPAN style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: Arial"> </SPAN></FONT></div>
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<div><B><FONT face=Tahoma size=2><SPAN lang=EN-US style="FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">From:</SPAN></FONT></B><FONT face=Tahoma size=2><SPAN lang=EN-US style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">re-wrenches-bounces@lists.re-wrenches.org [<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" target=_blank>mailto:re-wrenches-bounces@lists.re-wrenches.org</a>] <B><SPAN style="FONT-WEIGHT: bold">On Behalf Of </SPAN></B>Conrad Geyser<BR><B><SPAN style="FONT-WEIGHT: bold">Sent:</SPAN></B> 18 December 2009 5:42 p.m.<BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> nponzio@buildingenergyus.com; 'RE-wrenches'<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> Re: [RE-wrenches] solar hot water nighttime recirc</SPAN></FONT></div></DIV>
<div><FONT face="Times New Roman" size=3><SPAN style="FONT-SIZE: 12pt"> </SPAN></FONT></div>
<div><FONT face=Arial color=navy size=2><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">Nicholas,</SPAN></FONT></div>
<div><FONT face=Arial color=navy size=2><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"> </SPAN></FONT></div>
<div><FONT face=Arial color=navy size=2><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">You can certainly do that. Most newer controllers have a “vacation” function that will provide this. Another method is to put in a bypass to the check valve that you can open and the system will naturally reverse thermo siphon at night. Not much in the way of calculations other than the collectors reradiate as effectively as they collect.</SPAN></FONT></div>
<div><FONT face=Arial color=navy size=2><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"> </SPAN></FONT></div>
<div><FONT face=Arial color=navy size=2><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">Conrad</SPAN></FONT></div>
<div><FONT face=Arial color=navy size=2><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">Cotuit Solar</SPAN></FONT></div>
<div><FONT face=Arial color=navy size=2><SPAN lang=EN-US style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"> </SPAN></FONT></div>
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<div><B><FONT face=Tahoma size=2><SPAN lang=EN-US style="FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">From:</SPAN></FONT></B><FONT face=Tahoma size=2><SPAN lang=EN-US style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">re-wrenches-bounces@lists.re-wrenches.org [<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" target=_blank>mailto:re-wrenches-bounces@lists.re-wrenches.org</a>] <B><SPAN style="FONT-WEIGHT: bold">On Behalf Of </SPAN></B>Nicholas Ponzio<BR><B><SPAN style="FONT-WEIGHT: bold">Sent:</SPAN></B> Wednesday, December 16, 2009 10:54 PM<BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> RE-wrenches<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> [RE-wrenches] solar hot water nighttime recirc</SPAN></FONT></div></DIV>
<div><FONT face="Times New Roman" size=3><SPAN lang=EN-US style="FONT-SIZE: 12pt"> </SPAN></FONT></div>
<div><FONT face=Arial size=2><SPAN lang=EN-US style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Apologies if this has already been discussed here.<BR><BR>One heat diversion method I hear suggested often is recirculating through the collectors (flatplate) at night. Are there any data, calculations or anecdotal evidence on the effectiveness of this approach? That is, can I really radiate as much energy back to a dark sky as I collect during the day?<BR><BR>Thanks for any feedback.</SPAN></FONT></div>
<div><FONT face="Times New Roman" size=3><SPAN lang=EN-US style="FONT-SIZE: 12pt"><BR><BR>__________ NOD32 4697 (20091217) Information __________<BR><BR>This message was checked by NOD32 antivirus system.<BR><a href="http://www.eset.com/" target=_blank>http://www.eset.com</a></SPAN></FONT></div></DIV>
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