<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 12 (filtered medium)"><!--[if !mso]><style>v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style><![endif]--><style><!--
/* Font Definitions */
@font-face
{font-family:Helvetica;
panose-1:2 11 6 4 2 2 2 2 2 4;}
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:Consolas;
panose-1:2 11 6 9 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";
color:black;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p
{mso-style-priority:99;
mso-margin-top-alt:auto;
margin-right:0in;
mso-margin-bottom-alt:auto;
margin-left:0in;
font-size:12.0pt;
font-family:"Times New Roman","serif";
color:black;}
pre
{mso-style-priority:99;
mso-style-link:"HTML Preformatted Char";
margin:0in;
margin-bottom:.0001pt;
font-size:10.0pt;
font-family:"Courier New";
color:black;}
span.HTMLPreformattedChar
{mso-style-name:"HTML Preformatted Char";
mso-style-priority:99;
mso-style-link:"HTML Preformatted";
font-family:Consolas;
color:black;}
span.EmailStyle20
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>boB,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>There is a chart in that white paper that graphs the losses on each module in the string. No significant losses seem to occur until you get to 5 in series<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I can send the whole paper to you, or anyone, off list if you are interested<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Brian Teitelbaum<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>AEE Solar<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>bteitelbaum@aeesolar.com<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'> re-wrenches-bounces@lists.re-wrenches.org [mailto:re-wrenches-bounces@lists.re-wrenches.org] <b>On Behalf Of </b>boB Gudgel<br><b>Sent:</b> Saturday, November 20, 2010 5:14 PM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> Re: [RE-wrenches] Positive-ground question re Sunpower<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>On 11/20/2010 4:36 PM, Mark Frye wrote: <o:p></o:p></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";color:blue'>From the 2006 white paper:</span><o:p></o:p></p><p><b><span style='font-size:7.5pt'>"Polarization</span><o:p></o:p></b></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>Incorrect grounding of SunPower modules can induce a surface charge which would lower the energy production. Previously SunPower has announced the</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>discovery of the "surface polarization" effect which creates</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>a non-destructive and reversible accumulation of static</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>charge on the surface of high-efficiency solar cells such as</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>SunPower's A-300 cells [9]. When the cells have a high</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>positive voltage with respect to ground,</span><o:p></o:p></p><p class=MsoNormal><br>How high though ?? I would think that there might be some<br>curve that might show how high of V produces how much degradation ?<br><br>I assume that the lower voltage modules in the string work better ??<br><br>Maybe it's the other way around and the high voltage modules work better<br>when in a positive grounded system ?<br><br><br><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>a negative static</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>charge is built up on the surface of the cell due to current</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>leakage through the glass and the highly insulating front</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>surface anti-reflection coating of the cell. </span><o:p></o:p></p><p class=MsoNormal><br>I bet (or hope) that they fix this some day by changing the composition of<br>the glass, slightly, maybe.<br><br>Nobody seems to talk about this except for this one paper that we see.<br><br>boB<br><br><br><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>This negative</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>static charge causes increased surface recombination and</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>the performance of the module is reduced. If the polarity</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>is reversed and the cells are highly negative with respect</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>to ground, the negative static charge is replaced by a</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>positive static charge which restores the module</span><o:p></o:p></p><p><span style='font-size:7.5pt;font-family:"Helvetica","sans-serif"'>performance."</span><o:p></o:p></p><p><br><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Mark Frye</span> <br><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Berkeley Solar Electric Systems</span> <br><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>303 Redbud Way</span> <br><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Nevada City, CA 95959</span> <br><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>(530) 401-8024</span> <br><a href="http://www.berkeleysolar.com/"><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'>www.berkeleysolar.com</span></a><span style='font-size:10.0pt;font-family:"Arial","sans-serif"'> </span> <o:p></o:p></p><div><p class=MsoNormal> <o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div class=MsoNormal align=center style='text-align:center'><hr size=2 width="100%" align=center></div><p class=MsoNormal style='margin-bottom:12.0pt'><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> <a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">re-wrenches-bounces@lists.re-wrenches.org</a> [<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org">mailto:re-wrenches-bounces@lists.re-wrenches.org</a>] <b>On Behalf Of </b>jay peltz<br><b>Sent:</b> Saturday, November 20, 2010 4:30 PM<br><b>To:</b> <a href="mailto:Allan@positiveenergysolar.com">Allan@positiveenergysolar.com</a>; RE-wrenches<br><b>Subject:</b> Re: [RE-wrenches] Positive-ground question re Sunpower</span><o:p></o:p></p><p class=MsoNormal>Hi Allan, <o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I have seen the white paper from Sunpower, ( but don't have a copy) that shows the losses as the voltage rises if using neg ground.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>But from memory, if using at low voltages such as two in series there should be minimal if any "loss" of watts.<o:p></o:p></p></div><div><p class=MsoNormal>If you could use them as singles, for say a 12v system then there is no loss.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Jay<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Peltz power<o:p></o:p></p></div><pre><o:p> </o:p></pre><pre><o:p> </o:p></pre><pre>_______________________________________________<o:p></o:p></pre><pre>List sponsored by Home Power magazine<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Options & settings:<o:p></o:p></pre><pre><a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a><o:p></o:p></pre><pre><o:p> </o:p></pre><pre>List-Archive: <a href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a><o:p></o:p></pre><pre><o:p> </o:p></pre><pre>List rules & etiquette:<o:p></o:p></pre><pre><a href="http://www.re-wrenches.org/etiquette.htm">www.re-wrenches.org/etiquette.htm</a><o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Check out participant bios:<o:p></o:p></pre><pre><a href="http://www.members.re-wrenches.org">www.members.re-wrenches.org</a><o:p></o:p></pre><pre><o:p> </o:p></pre><p class=MsoNormal><o:p> </o:p></p></div></body></html>