Solar Panel Voc-MPPT?
Wondering if there is any relationship between measured Voc and MPPT performance with a 24v panel. My 12v panel has a Voc rating of 21.9 and Isc of 8.2, but I often see 8.2ish when Voc is only 20....
Forum Discussion
red31 wrote:BFL13 wrote:
“Annual income twenty pounds, annual expenditure nineteen six, result happiness. Annual income twenty pounds, annual expenditure twenty pound ought and six, result misery.” Dickens.
How about an over/under pool? pic a voltage and amp, same location, same time of year, solar noon, clear blue sky ...
If the over/under is 16A @13.5, put me down for under
230w with 12v and PWM would get me 14.5a until low 13s. By 13.5 I would notice a slight drop due to the IV curve. Happiness would be to get more than 14.5 with MPPT -- at least another 1.5a for 16a.
So under 16 is misery! However, there is also the claim that MPPT does better on daily AH haul by doing better in the shoulder hours or in poor light, even if it does little better an actual amps at noon.
Seems kind of lame in comparison with just seeing way better amps on the Trimetric.
That would be harder to notice and measure too. Have to repeat those tests from a couple years ago. Be a desperation last ditch attempt to prove I didn't waste my money if I only get 15a instead of 14.5
I knew that going in though, which is why I only did it when I was going to have to get a new PWM controller anyway so the diff in price in moving "up" to the Eco-Worthy at $108 was "worth a try." Maybe the thing only works at 10,000 ft and you need a Sherpa to carry it up there for you like JiminDenver does. :)
