Usefulness Of MPPT Technology

MrWizard wrote:
@ PT

Doesn't take long before panel AC becomes attractive. I have a Trace 4024 inverter and 1,650 amp hours @ 24V worth of batteries. And some 19.0 voc Kyocera panels. I'll keep the Kyoceras for 12 volt LED illumination for emergency lighting.

@BFL
430w for A/C ,lets calculate 10% conversion loss
483w used at 24v...20amps at 24v into trace inverter per hr of usage

4hr = 80ahr AKA 4hr*483w = 1932wHrs

daily return needs to exceed 2KW hrs aka exceed 80AmpHrs at 28v charge

Mexi
360w / 28v = 12.85 amps that NEEDS at least 7 hrs of solid Full power SUN, to return/power the A/C

I would go with 540w or even 720w and a 30amp or larger mppt controller
you can avoid mppt IF your panels are in the 30v peak range, just wire all in parallel and use a 24v system pwm controller

i think 360w would be the minimum system for A/C use, and would limit your hours
you have more than enough battery bank, but might be operating at a deficient if you use over 2-3hrs of A/C per day

i'm not up on the efficiency ratings of the different mppt controllers
but with the major brands blue sky, rouge , outback
i don't think there is more than a few percent difference between them

the blue sky 2000e can be set 24v system and use 30v panels, but its limited to 25 amp output, it can accept panels that will produce more, but it will limit the output
i have 505 watts, "rated", but i have never gotten that much from them
345-350w (25.1 amps at 13.8v) is around the Max i have seen but my panels are flat mounted
but 25 amps at 28v would be 700w, and be right in the ballpark for your needs

you can extrapolate from there
1000w 35+ amps
1400w about 50amps

24v 235 w solar panel from solar Blvd Vmpp at 29.8V, like $.67 per watt two or three should do you. see the PWM charge controller link on ebay above for options... single 30 amp one or 3 10 amp ones, one per panel. Reduncancy for if one fails, the others keep on working?

Are you going to need 14.8v x 2 or 29.6V to fully charge 100% these banks of 24v batteries? Just thinking out loud, with your 24v system, the margin of over voltage is thinner, although, so are the losses. Panels that track the sun stay far more efficient, than ones un aimed, although where you are at lattitude wise, is that a non issue with fla panels?