12 volt fridges and boondocking?

2manytoyz wrote:


The temperature of the RV, and how often the fridge door is opened, will play a big part in how often the compressor runs. Looks like the 8 cu ft fridge draws ~5A/HR.

Just a wild guess, a 50% duty cycle of 5A/HR, is 2.5A/HR x 24 hours = 60 Amps x 12V = 720 Watt Hours per day. 600W of solar, with a derating factor of 25% = 450W of actual production. During peak sunlight, you'll replenish all the energy used by your fridge in 1.6 hours.

I have made a lot of measurements for my 12v Nova Kool compressor refrigerator. The run time is highly dependent on ambient temperature. In the 65-70 degree range, my unit runs roughly 1/4-1/3 of the time. I do a lot of summer camping and day temps are often well in the 80's. That 10-15 degrees has a huge impact. Run time increases to about 75% of the time. A few degrees more and the unit will run almost continuously and does not cycle again until temps drop in the evening. Those are measurements without using the refrigerator. When opening and closing the door numerous times a day or trying to cool down some water or other drinks, the unit can easily run continuously with temps barely above 80 degrees.

A unit that pulls 5 amps is likely to use roughly 100 AH/day for moderately warm Summertime camping.

I use the following calculator to estimate maximum solar output:

http://www.where-rv-now.com/Notes/Solar/index.php#Calculator

For my latitude at this time of year, 600 watts of solar is barely enough to output 100 AH/day with full open sun and no clouds. Mid Summer peak would be roughly 300 AH/day, enough to run the refrigerator for at least 3 days on warm days without any additional solar. Certainly the OP should be able to do well with this combination of use and solar.