[RE-wrenches] CEC module rating testing

[Jerry Caldwell]

Gents, thanks for the responses.  

Joel's spreadsheet indicates that the CEC at least was at one time simply using the NOCT &  temperature coefficient of power to determine PTC rating.

Dave, if your attachment is anything different from what Joel sent I welcome you to send it my way.

My brother who works for a manufacturer sent me the following response:


"We send our modules out for
testing at ASU's Photovoltaic test lab (now TUV-PTL)  I just looked at a
report.  Seems data is taken from 3 different test conditions:  STC
(1kw/m2 & 25C cell temperature), NOCT (800W/m2, 20C ambient temperature),
Low irradiance (200W/m2, 25C cell temperature).  This data is used to
establish the temperature corrections to report data for the PTC conditions
(1kW/m2, 20C ambient).
The report says that the NOCT data was taken outdoors.  The other tests
require that the cell temperature be 25C, and I think for that they must do
indoor testing."But as Anthony pointed out, if STC is the basis for PTC then it all hinges on the manufacturer's +/- tolerance.  This makes it difficult to accurately estimate and compare system performance of different modules, which is becoming increasingly important for large systems and PPA's.

Best,
Jerry Caldwell



________________________________
From: David Katz <dkatz at aeesolar.com>
To: RE-wrenches <re-wrenches at lists.re-wrenches.org>; solarcowboy at yahoo.com
Sent: Monday, December 1, 2008 6:48:16 PM
Subject: Re: [RE-wrenches] CEC module rating testing

Jerry,
The CEC formula for PTC uses the NOCT of the module, the STC rating,
the power temperature coefficient and the aperature area of the
module.  
The data is supplied by the manufacturer but must make sense.  Starting
July 1, 2009, this will have to be certified by an acredited testing
lab.
Let me know if you want the exact formula and i will send it to you.  i
can't attach anything to this email
David


Microsoft Outlook Signature  
David
Katz
President
AEE Solar
1155 Redway Drive
P.O. Box
339
Redway, CA 
95560
Tel
(707) 825-1200
Fax
(707) 825-1202
david at aeesolar.com
www.aeesolar.com
 
DISCLAIMER: 
This communication, along with any documents, files or attachments, is
intended
for the use of only the addressee and contains privileged and
confidential
information. If you are not the intended recipient, you are hereby
notified that any dissemination, distribution or copying of any
information
contained in or attached to this communication is strictly prohibited. 
If
you have received this message in error, please notify the sender
immediately
by e-mail reply and destroy the original communication and its
attachments
without reading, printing or saving in any manner.
P Pleaseconsider
the environment before printing this e-mail.

Jerry Caldwell wrote: 
Wrenches,

Can anyone tell how PTC ratings are determined for modules on the CEC
list of eligible modules?  I seem to recall having heard that the
manufacturers provide this data on the honor system.  Can anyone verify
this?

The test is obviously more involved than flash testing at STC.  Even
though PTC is supposed to simulate more real-world conditions, it must
still require a controlled environment.  How exactly is this done, and
how long does it take?

Best,
Jerry Caldwell
Recurrent Energy



________________________________

_______________________________________________
List sponsored by Home Power magazine

List Address: RE-wrenches at lists.re-wrenches.org

Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org

List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org

List rules & etiquette:
www.re-wrenches.org/etiquette.htm

Check out participant bios:
www.members.re-wrenches.org 


      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20081202/e5632ca3/attachment-0003.html>