Eco-Worthy 12v solar panels, Now drifting to... mono vs poly
When I search here, the only Ecoworthy results I get are for their controllers. Does anyone have any experience with their 12v panels?
Forum Discussion
jrnymn7 wrote:
That's what I thought, BFL, so going with either the 130w or 100w would be well under the controllers limit. And if I was looking to go series, I wouldn't even consider maxing out the Voc on that Eco-W mppt.
At 21.92 Voc, and a .38%/C rise; at 0C, Voc would only be 22v, correct?
My Sharp 130w panel was 21.9Voc and V coefficient of -0.36/C, so dropping 25C would make the Voc go up by 25 x 0.36 = 0.9v to 22.8v
However in the sun, panel temp goes up quite a bit, so I am not sure how the ambient temp matters so much. That's what they say in their blurbs though , to allow for ambient cold.
Eg at 16C ambient my 230w panel (at the back of it) was 44C and Voc was 34 instead of rated 36.8. At 25C panel was 51C and Voc was lower.
The solar blurbs say to expect a 10% loss in output with panel at 50C instead of 25C and that is why I was getting 13.5 amps instead of 15.5 amps more or less with the MPPT which is voltage dependent.
PWM could care less about voltage and you get Isc no matter what. That's why I like the Solar30 and a pair of 12s in the summer instead of a big 24 and MPPT (if the money works out right)
