That would be cool. I’m already running Artsolar arrays. I’m sure matching fencing would look great.
Just not so sure if that fence will keep the thieves from stealing your solar panels ! 
Sorry to resurrect this thread but I have a question in the same vein - as far as I can tell this would also apply to mixing Mono and Poly Panels in the same string?
Currently have 6x340W Poly Panels - VMP=37.74V and IMP=9.01A
Want to add 3x370W Mono Panels - VMP=39.6V and IMP=9.35A
Estimating the output of the 340W panels stays the same and the 370W Mono will produce 39.6Vx9.01A=356W.
The Poly panels are like hen’s teeth, very hard to find! And the Mono Panels are almost the exact same size as the old Poly and at a reasonable price. Artsolar say they are producing more 340W poly panels but haven’t given me an exact date yet or a price. And I wouldn’t mind a few extra Watts of power as these are the last three panels I can fit on my roof!
Hi JaseZA,
You are both correct and wrong on the Watt out. You have to take the MPPT into account, once you start putting different panel together the MPPT might even end up being less optimal on the original panels! But ultimately, you will not have less power that original installation!.
On that note, I am installing Module Level Optimisers on my system, this would effectively eliminate the mismatch. Will most likely post my findings on this forum a bit later (once they are in and tests have been run).
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They sometimes interfere with an MPPTs ability to find a good power point, because they tend to flatten things. I’ll wait for your results… 
Thanks @Rautenk - plans have actually since changed and I’m hopefully receiving Canadian Solar 365W Poly Panels at the end of the week. These are 39.8V @ 9.18A Poly panels so a little bit closer to my original spec. Will definitely post some results of how it all performs together once they’re installed - hopefully the MPPT behaves! I’m hoping for 39.8V x 9.01A = 358W output, or an relative increase of 52.5% for my string. Time will tell…
The not so long wait is over!
My first draft analysis on module optimisers for residential can be found on this link:
Last 7 days of solar - you can see where I added the new panels! They’re performing great, max in clear weather is up 1.65x (Calculated should have been 1.525 times more!)
Noticed an interesting glitch in the MPPT of my Voltronic VMiii MPPT - seems now with the mixed panels it figures out a better voltage point a bit later in the morning and suddenly produces a bit more power. Example below of my original panels being quite consistent and then the new mixed panels. Might just be the higher voltage as apposed to the mix.
Don’t think there is much I can do but thought it was interesting enough to report.
Is the MPPT’s volts sitting at 350V!? Did you put the new panels in series with the old ones or in parallel? Are you running a Victron MPPT or something else? Victron’s MPPTs are designed only to run up to 100/150/250 (or the new one 450) volts. If you don’t have the new one, I’m not sure how it is getting up to 350V… without blowing up.
New Voltronic VMiii - 500V max Voc so no issues running in series. My theoretical Voc is 420V.
Indeed. Depending on shading and other factors, the P/V curve could have multiple peaks, and if the MPPT does a rescan (which most periodically do), it may find the other peak. The change from the one to the other may also be a clearly visible event, since it is triggered by a rescan.
In applied math we called this a “local maximum”. It’s like when you climb a mountain, and you finally get over the edge just to see that there is more mountain to climb. Now imagine you couldn’t see very far, and then you know what an MPPT has to do. Sometimes it gets stuck on a small hill for half an hour, then it stops, takes a sip of water, puts on its glasses… and then it moves higher up
Thanks plonkster, makes sense. I imagine it must be fun trying to figure out the best optimization in terms of how often to scan, how far to scan and not losing too much output while scanning!
Interestingly, I measure at 5 second intervals and I see no drop in PV power during the change or before it - not sure how the MPPT manages to test the best V/I position without dropping any power? Unless it’s quick enough that I don’t measure it in between the 5 seconds.
