The other side of just having SOLAR PANELs is if you want to charge your batteries in a quick three hour recharge time the solar panels may not produce enough initial DC Amps to do this. There is rules for charging deep cycle batteries which wants you to start out with 14.4VDC@17-20AMPS DC Current for each battery you want to be charging. A 120WATT SOLAR PANELS may only produce around 5-6AMPS usable DC CURRENT.
This is the same reason as in one of your other comments "why can't I just use the Battery Charging cable that come with the generator to charge my battery." There is usually only unregulated 12VDC on this cable and only has the capacity of around 6-8AMPS DC Current. This will work but will take many many hours to charge your battery. To charge a battery in a quick three hour time period battery science as stated by PROGRESSIVE DYNAMICS says you need to have around 14.4VDC with the capacity of 17-20AMPS for each battery being charged.
What works for me is having a battery bank that runs all of the things I want to run using an Inverter and direct connected to my battery bank terminals. I can use my battery bank to run these items until it reaches it 50% charge state which is indicated by reading around 12.0VDC at the battery terminals. Then I will want to re-charge the batteries by connecting my smart mode converter/charger or a portable smart mode battery charger to the 120VAC Receptacle of the generator which will start charging my batteries. This will take three hours to get from 50% to 90% charge state.
Bottom line is I need 14.4VDC@17-20DC-AMPS capacity for each battery being charged in the battery bank and will also need my generator capacity to be able to operate the converter/charger or the portable battery charger.
Not many ways around these requirements.
If you want to use the solar panels then unless you can get 14.4VDC@17-20AMPS of usable DC power from them it will still charge your batteries but will take much longer time. The problem will be you will run out of HIGH SUN before you get them back up to their 90% charge state. You can only get almost full performance out of your battery bank when you start out with a 90% charge state. Of course 100% charge state is best to have but that will take a good 11-12 hours of charging using 14.4VDC@17-20AMPS DC current available. This is battery charging science again at play here.
I would want to use the generator method as primary and fall back to SOLAR when you have high sun available. Actually only running the generator for the initial high current stage of charging and then switch to solar power for the remaining sealing time might be a good solution to not have to run the generator as much.
Just my thoughts
Roy Ken
My Posts are IMHO based on my experiences - Words in CAPS does not mean I am shouting
Roy - Carolyn
RETIRED DOAF/DON/DOD/CONTR RADIO TECH (42yrs)
K9PHT (Since 1957) 146.52M
2010 F150, 5.4,3:73 Gears,SCab
2008 Starcraft 14RT EU2000i GEN
2005 Flagstaff 8528RESS