Lets run the numbers on a 5000 btuh a/c.
I looked at a few and I think we can figure on a load of 5 amps at 120V. Figure on running 8 hours a day and the energy demands would be 600 watts*8 hrs =4800 watt-hrs. According to PV Watts, to harvest this much energy in a day in south Georgia you would need:
4800 watt-hrs/5.5 hours (peak sunshine hours in Georgie)= 872watts. Throw in a deration factor for conversion losses of .77 and the array size would be 1133. Let's round up to 1200 watts. This is for a fixed, non-tilting array and doesn't include any other loads. It also doesn't account for cloudy days.
You could minimize the battery bank size to only support starting of the A/C but you'd need to be careful to turn the A/C off as soon as the sun went down. Otherwise your batteries would be dead in an hour or so.
I would start looking around for panels and I would stay away from the cheaper type if you plan on using the panels long term. NAWS is a good source for PV stuff:
250 watt solar panel5 of these would work.
Larger panels are cheaper per watt but are usually at a higher voltage than a 12V charging panels. You'll need an MPPT controller to charge the battery and I like Morningstar
Morningstar Tristar MPPTWe can look at battery voltage, bank size and inverters next if you aren't scared off by the numbers so far.
If you want to shoot for the moon, here's grid tie, battery backup inverter that does everything. That way you could sell your power back to the utility if your not running the A/C and still have complete battery backup.
Outback GTFX SeriesBruce
P.S. That reminds me, I've got 560 watts total on my trailer now, maybe I'll try running my A/C from the array sometime...