Keeping the frig alive in storage

[SternHappens]

So we have a 2015 Georgetown 364TS with the big Frigidaire residential frig. We usually go out every other weekend but are not suppose to leave our unit in the driveway per homeowners restrictions, so we normally keep it in a gravel lot a couple of miles down the street, but it has no power hookupstitally emptying that frig is a major hassle for only a week and we would basically an extra frig close to the same size for the stuff since our house frig won't accommodate it, not to mention remembering to empty 2 ice makers.
I found a covered storage place that let's you plug into 20amp service the power cycles and you only get 2 hours of juice per 24 hours.

So my question is this: is 2 hours of electricity per day enough to keep the battery bank sufficiently charged to power only the frig? And if there is a negative drain how long would the batteries last before dead? How do I make these calculations? My thinking is even if 2 hours is enough for a full charge, starting with fully charged batteries, if I had to run over once a week and fire up the unit or generator for an hour to give the batteries a better charge, would that be enough to keep the frig going? Thanks for any assistance.

[23dks]

Here is a simplified calculation to determine your fridge run time on batteries. You will need the electrical specs for your fridge, battery, and inverter. The Frigidaire website shows the FPSC2277RF 22.6 Cu. Ft. side-by-side pulls 8.5 amps at 120 vac. The Trojan Battery website shows the 24TMX has a capacity of 36 minutes @75 amps. I chose 90% as the inverter efficiency.

First multiply your fridge’s running amps and the ac supply voltage to get watts:
8.5 x 120 = 1020 watts from the ac supply

Multiply ac watts by 1.1 to account for inverter efficiency of 90%:
1020 x 1.1 = 1122 watts from the dc supply

Divide dc watts by 12vdc to get required dc amps:
1122 / 12 = 93.5 amps from the battery

If you are using the Trojan 24TMX battery, your fridge will run about 30 minutes before the battery is discharged.

You will need to determine how long your fridge operates on each cycle to determine how long the battery will last but I don’t think you will get more than 2-3 hours out of the example battery. You will need quite a bit more battery storage than one Trojan 24TMX to run your fridge for a day.

To recharge the battery you will need to put back in it the same amount of energy you took out of it. Looking at the 24TMX specs I think you will need to charge the battery at about 30 amps to recharge in your two hours of allotted power.

With a capacity of 121 minutes @75amps, the Trojan J185H-AC will run the example fridge for about 100 minutes. It weighs 123 pounds compared to 47 pounds for the 24TMX and will need significantly more charging current to get recharged in two hours.

Using the batteries in this manner will decrease their life and require more frequent water checks. Battery life is typically given using small and infrequent discharges.