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</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:14.0pt;color:#1F497D'>I suspect that SunPower gets their advertised high performance, not from having better technology, but by being more selective in matching higher power cells than just randomly divvying up cells off a common factory run. The module you’ve found Marco may just be a slipup in sorting (nothing is 100%) and may not indicate a change in that module but just what that module would have shown from the beginning. Those you’ve tested, boB, might just be from a manufacturer with wider selection range and also was there from the factory line. A change would be more worrysome.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#1F497D'>Bill Dorsett<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;color:#1F497D'>Manhattan, KS<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt;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 [mailto:re-wrenches-bounces@lists.re-wrenches.org] <b>On Behalf Of </b>boB@midnitesolar.com<br><b>Sent:</b> Saturday, November 21, 2015 11:49 PM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> Re: [RE-wrenches] module hot spots<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><br>I have looked at several modules (not SunPower though) and I see this much temperature<br>variation between cells BUT I have not seen anything like your picture, with only one cell<br>hotter. What I have seen is hotter and cooler cells more or less spread out<br>semi-randomly. Not sure if your example is normal or not for Sun Power ?<br><br>Here is one example from my library of FLIR pix.<br>A thermal imaging camera sure sheds light<br>on many different things !<br>boB<br><br><img width=320 height=240 id="_x0000_i1025" src="cid:image001.jpg@01D12503.1F7AB4C0"><br><br><br><br>On 11/21/2015 9:31 PM, Marco Mangelsdorf wrote:<o:p></o:p></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'>Hello all,</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'>I’m seeing hot spots on some of the SunPower modules we installed circa 2007-2010. (I’ve been a SunPower dealer since 2005.)</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'>Sometimes theses cells are 20-30 degrees C hotter than the surrounding cells and it’s especially striking while using a Flir IR camera. Check out the two images below.</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'><img width=339 height=254 id="Picture_x0020_1" src="cid:image002.png@01D12503.1F7AB4C0" alt="cid:image001.png@01D12070.CBCC60D0"><img width=339 height=254 id="Picture_x0020_2" src="cid:image003.png@01D12503.1F7AB4C0" alt="cid:image002.png@01D12070.CBCC60D0"></span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'>Do many of you come across hot spotted mods? Anyone know of any papers out there on hot spots and the hit on performance and reliability?</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'>Mahalo,</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman , serif","serif"'>marco</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><br><br><br><o:p></o:p></span></p><pre>________<o:p></o:p></pre></blockquote><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'><o:p> </o:p></span></p></div></body></html>