Usefulness Of MPPT Technology
This isn't a trick question. I wish to take a "Short Course" in the reality versus hype of MPPT control... Users who have MPPT and can report real-life experience... Let's say I get a pair of panel...
Forum Discussion
JiminDenver wrote:
BFL
I ran your formula for my 230w panel and got 14.5a even though it's rated for half that. I do see 13 to 14a in PWM absorb mode at altitude and 16a in MPPT.
Yes two 115w 12v panels with PWM should get 14.5a and one 230w "24v" should get at least that plus your MPPT premium of 10%, so that would be 14.5 + 1.5 =16.
I gather the "PWM absorb mode" is with the Eco-Worthy. I find this description peculiar because supposedly with PWM you can't get more than Isc (about 8.3a) of the 230w panel. Yet the controller is getting 13-14a, so it must be still bucking the input (in MPPT) but calling it PWM. Or else, I have to un-learn something! (wouldn't be the first time)
EDIT--They say that when it is mostly sunny, there isn't much if any advantage in going MPPT. Also in high temps (panel temps) MPPT suffers whereas PWM does not (MPPT sees the voltage drop with heat and loses amps from that while PWM uses Isc which goes up with heat)
Looks like Mex might be better off with PWM controllers, but that means using several 12v panels, can't use the big '24v' ones. The big panels are cheaper but the MPPT controllers cost more. Can't win!
