Mixing panels - will this work?

[wolfandy]

Hi all

I am looking at changing my current panel configuration and adding more panels (use 4 existing ones and add 2 additional ones). My problem is, that the panels that I currently have are not easily available anymore. My installer has offered me used ones (21 month in usage) at what I deem an unacceptable price. I therefore would appreciate your guys' view on if I can mix my current panels together with new alternative ones:

My installer wants R 200 more for the used panels than I can get the new panels for. I understand that I will have slight efficiency losses by taking the new alternative ones - but the question is whether this will actually be noticeable (this string is less than 1/3rd of my total PV)

I am leaning to the new alternative ones. What would you recommend?

[JaseZA]

If connecting in series with old panels, you'll lose 0.01A in the string - 2.4W of 2260W... I would go for new panels. Your current panels have probably lost way more than that with age already.