Drake, I measured and published a paper in 1992 on the after 10 year performance of solar modules, my study concluded these modules degraded approximately 1% per year. The purpose of the study was the effect on utility demand. I have heard there are some very good studies with similar results. Thank you--Darryl
--- On Fri, 4/9/10, Drake Chamberlin <[email protected]> wrote: From: Drake Chamberlin <[email protected]> Subject: Re: [RE-wrenches] Voltage degradation To: "RE-wrenches" <[email protected]> Date: Friday, April 9, 2010, 12:24 AM What is the documentation for 10% module voltage degradation? I have heard different ideas on what will degrade over how much time. For direct grid tie, I shoot for a voltage drop 1% maximum on the DC side. Thanks, Drake At 11:08 AM 4/8/2010, you wrote: I usually keep in mind that the modules will degrade by 10% However, if you are one of those wrenches promoting 3% DC Voltage Drops, maybe you should add some more. Nick Soleil Project Manager Advanced Alternative Energy Solutions, LLC PO Box 657 Petaluma, CA 94953 Cell: 707-321-2937 Office: 707-789-9537 Fax: 707-769-9037 From: Drake Chamberlin <[email protected]> To: [email protected] Sent: Tue, April 6, 2010 1:58:56 AM Subject: [RE-wrenches] Voltage degradation Esteemed Wrenches, How much voltage overhead should we have available on our arrays to allow for inverters not to fall out of their DC voltage operating range? Since the module power degradation is 20% over the warranty period, I usually shoot for a module voltage that can drop 20% and still be within the MPPT range of the inverter under the average high temperatures, since most of the degradation is in voltage. Am I being too conservative with this number? It always pushes the number of modules to the top of what is allowable on the string for the extreme low. Thanks, Drake Chamberlin Athens Electric OH License 44810 CO License 3773 NABCEP TM Certified PV Installer Office - 740-448-7328 Mobile - 740-856-9648 _______________________________________________ List sponsored by Home Power magazine List Address: [email protected] 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 Drake Chamberlin Athens Electric OH License 44810 CO License 3773 NABCEP TM Certified PV Installer Office - 740-448-7328 Mobile - 740-856-9648 -----Inline Attachment Follows----- _______________________________________________ List sponsored by Home Power magazine List Address: [email protected] 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
_______________________________________________ List sponsored by Home Power magazine List Address: [email protected] 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
