<div dir="ltr">I second Jay's request for some numbers, I'm curious about this not having participated directly in any bifacial projects yet. The difference in Voc and Vmp ratios is interesting.<br clear="all"><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><br></div><div>Brian Mehalic <br>NABCEP Certified Solar PV Installation Professional\u2122 R031508-59</div><div>National Electrical CodeŽ CMP-4 Member</div><div>(520) 204-6639<br><div><br></div><div><div><div>Solar Energy International<br><a href="http://www.solarenergy.org" target="_blank">http://www.solarenergy.org</a></div></div></div></div><div><br></div><div>SEI Professional Services</div><div><a href="http://www.seisolarpros.com" target="_blank"><span style="font-size:12.8px">http://www.s</span>eisolarpros.com</a><br></div><div><br></div></div></div></div></div></div></div></div></div></div></div></div><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Nov 2, 2020 at 8:55 AM Jay <<a href="mailto:jay.peltz@gmail.com">jay.peltz@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Hi Jason,<br>
<br>
What are you seeing in terms of measurements?<br>
<br>
Temp air/module <br>
Voc<br>
Irradiance<br>
Etc<br>
<br>
Jay<br>
Peltz power<br>
<br>
<br>
> On Nov 2, 2020, at 8:18 AM, Jason Kechijian <<a href="mailto:solarj@me.com" target="_blank">solarj@me.com</a>> wrote:<br>
> <br>
> \ufeffHey wrenches,<br>
> <br>
> Does anyone have any guidance to which values to use when testing open circuit voltage on bi-facial modules, considering you take the temperature reading from the cell vs. the back sheet? Also, what would be the correct module Voc to use since there are values for both the front and back?<br>
> <br>
> 405W Module: Front/Back<br>
> Pmpp: 405 / 285<br>
> Vmpp: 40.89 / 41.10<br>
> Impp: 9.91 / 6.94<br>
> Voc: 48.42 / 46.99<br>
> Isc: 10.38 / 7.28<br>
> Module efficiency: 19.7% / 13.9% <br>
> Temp coefficient Pmpp: -0.3528%/ēC<br>
> Temp coefficient Isc: +0.0400%/ēC<br>
> Temp coefficient Voc: -0.2769%/ēC<br>
> Nominal: 44+/-2ēC<br>
> <br>
> I was using the front Voc and Voc temp coefficient, but I am getting some results which are not in line with the 5% of expected.<br>
> <br>
> Jason D. Kechijian, LEED AP<br>
> NABCEP Certified PV Installation Professional\u2122<br>
> <br>
> <br>
> <br>
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</blockquote></div>