Author Topic: Home Solar Array? How much? Worth it?  (Read 6325 times)


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Re: Home Solar Array? How much? Worth it?
« Reply #100 on: February 26, 2020, 09:22:45 AM »
My panels are rated for 385W. Is this normal? I just got access to the monitoring software like 30 minutes ago, so I don't know what I'm doing, but some of my panels are performing close to 600W (according to the online dashboard). Is that typical? Rated for 385 but give me 600? Seems unlikely and crazy...

385w is the nameplate output of your panels - what they will do under some very narrow testing conditions (e.g. temperature, irradiance, resistance).  385W is the middle of the range of newly manufactured PVs - you can pay (a lot) more for 400w or now even 425w panels ó but, if you have the space itís cheaper to just add a few more panels than go from 385w to 425w nameplate PVs

Itís also common for panels to produce more than their nameplate ratings under very good conditions (temperatures < 70ļF, bright sunny day).  585w on a 385w panel does seem suspiciously high to me... but itís possible?  Iíd check with the installer and read your white papers on panel performance.  Itís possible that theyíve optimized newer designs so they can take advantage of optimal conditions more. 

In my previous home we had older 270w panels, but it wasnít uncommon for them to output 350wats on cold clear days.  Contrary to my expectations, sometimes partly cloudy days briefly produced the highest output, as the edges of clouds could act as a Ďlensí focusing light, and the clouds kept the panels cooler.