Quote:
Originally Posted by davidmiller
Hi ecorenovators!
I am facing a tough challenge. I need to choose between brand new and used solar panels for my 7kW PV system. I'm more inclined toward brand new panels simply because of higher efficiency and warranty. But on the other hand the second hand panels are so much cheaper...I would save few thousands with used panels. I did some research on efficiency and I'm sort of convinced that new panels are a better option...but a good friend of mine told me that panel efficiency is not important when it comes to ROI.
I kindly ask anyone here to write their opinion on this, maybe someone that bought used panels. I wonder that's the conversion ratio from sunlight to electricity on used panels...theoretically should be much lower right? but how much? |
I can only show you the efficiency of my panels over 14 years of use.
My website is in Dutch, but the graph speaks for itself: vertical=efficiency (based on panel area, not cell area) and horizontal=years
Degradatie en vervuiling van de panelen - geen energierekening meer:energie+ woonhuis van de fam. Kriegsman in Ootmarsum
The increase in 2011 was because a small ventilation pipe was removed from the roof. So a little shading of one of the six rows of panels had a significant effect.