It's not uncommon for me to lose power a few days a year due to weather related events. While this is not usually a big problem, I was considering a solar panel and battery system just to run my refrigerator, so at least my food would not spoil during those outages. I was thinking the simplest solution would be to just run the refrigerator from the battery full time, rather than needing some system to switch between the grid and battery. Assuming the average requirement for a refrigerator is 150 watts, isn't that 1800 watt / hours per day? Assuming battery to provide that 24 hours per day would need to make be a 150 amp hours available per day. Assuming a 100 panel provides 300 watt hours per day, it would take 6 100 watt panels to run that refrigerator 24 hours per day. Of course, this is not considering efficiency loss or compensating for overcast days, but just taking these number, there must be something very wrong, because I have seen many RV channels powering a refrigerator and more with much less solar capability. These numbers come from a quick google search but can someone tell me where the error is and a realistic way to calculate those needs?