I purchased 30 used Sunpower E-Series Commercial Solar Panels E20-435-COM from ebay and they are advertisted to be working at 98% of out of the box capacity. However, when I tested several of them today in clear, direct sunlight, I'm only getting 80-85% of the rated 435w output. Did I get ripped off?
At first, I was shocked and very disappointed at such a low output. I paid up for these panel compared to other offerings on eBay and considering the wording of the ad, I thought was expecting more. Now to be fair, on a percentage basis, they did do slightly better than my existing 265w panels, but I was really expecting over 400 watt in direct sunlight...especially since it was so cold here today (near freezing).
So am I expecting too much from these panels or was I straight up deceived by the seller? Please chime in...
The pictures below show the readings from the charge controller and the position of the sun at the start of the testing. The result got worse the more I tested so that is likely related to the sun moving farther west. I guess I really can't complain since they are outperforming my existing panels. But I was hoping for that 98% claim. Maybe when the sun is higher.
At first, I was shocked and very disappointed at such a low output. I paid up for these panel compared to other offerings on eBay and considering the wording of the ad, I thought was expecting more. Now to be fair, on a percentage basis, they did do slightly better than my existing 265w panels, but I was really expecting over 400 watt in direct sunlight...especially since it was so cold here today (near freezing).
So am I expecting too much from these panels or was I straight up deceived by the seller? Please chime in...
The pictures below show the readings from the charge controller and the position of the sun at the start of the testing. The result got worse the more I tested so that is likely related to the sun moving farther west. I guess I really can't complain since they are outperforming my existing panels. But I was hoping for that 98% claim. Maybe when the sun is higher.