fromport
Solar Addict
Because i am in southern cali, temps are easily why higher that STC rating and thus I see less power.What about summer?
But that is why I said in spring, goof sunny sky but not high temp yet, almost mimicking STC conditions I see/measure 140+ watts out of a 158 watt rated panel that is 20+ years old. Pretty good imo.
Nice, I assume the high altitude lowers your ambient tempconsiderably?My 3 yr old Talesun 330W panels rarely perform to STC spec because STC spec rarely happens in the real world. I get closer to 90%. My panels are at 6500 ft, in the AZ high desert, so they actually get more than 1000W/m^2, and they experience more mild ambient temperatures than Phoenix, but 90's are pretty common.
My best performance is in the colder months where panel tilt is not as favorable, but the notable cold boosts Vmp. I've seen 110% in those conditions.
No matter what kind of panels you buy, you will only get 80% of the rated wattage IRL.Thankyou for taking the time to explain this.
185w kinda sucks lol I may just spend the money with santan solar on some of their used panels. They seem to be more reputable. Or maybe I’ll bite the bullet on new panels. I just don’t know where I can purchase 5-6 opposed to a pallet
That is because when there is a lot of sun the ambient temperature gets warmer than 25C/77F.
A new solar panels de-rates the most in the first few years, after that it slows down and becomes a steady percentage of like 0.1%/year.
If you don't need the higher watts/sq surface (not on roof van/rv), I would definitely advise to go with used solar panels.
They will last a lot longer than you think. Can't beat the bang for the buck. Some models of sharp panels had de-laminating problems with the film at the back but that was mostly with 160-180 watt panels. $70 each for 230 watt is $0.30/watt. You should try and get that down to $0.20 so I would offer him $45 per panel.