Running a 240 volt fridge via an inverter.

Hi Folks, I haven't been on here in ages, but recently bought an old Cabana Caravan to take the grandchildren camping. Anyway, I thought I'd share this

Running a 240 volt bar fridge from a 12 volt battery via an inverter when off grid. Firstly whilst I don't claim to be Collyn Rivers, I've been around 12 volt camping stuff for years, own a related business and used to fit dual battery systems. Given I had the gear kicking around I put it to the test.

I have an old Varta 100 amp AGM that is a bit tired but not too sick (it will hold 12.75 volts wheras a new fit one will hold 13.0). I ran the fridge (an old 90 litre NEC cheapie that came with the van) on 240 yesterday filled with cold stuff. At 8pm I plugged the fridge into the inverter and ran it overnight. At 8am today the battery (standing voltage) was at 12.2.

I then plugged in the 300 watt solar panel setup and continued running all day via the inverter on a miserable Melbourne day. The sky as you see it in the photo was pretty much how it was all day with regular rain. I shut it all down at 6pm and let the battery settle, it showed 12.42. In effect on a very solar unfriendly day, the solar had run the fridge and inverter, and had "banked" about 20 amps.

Running a 240 volt fridge from 12 volt through an inverter is highly inefficient compared to running a proper 12 volt compressor fridge. However if you have sufficient solar it can be done. Certainly on a day with as little as two hours sun and the rest of the day overcast, with this setup it will work.

Note, the inverter is a Giandel 1000 (2000 surge) watt pure sine wave unit which are only a bit over $100 these days. The 300 watt solar gear was $175 from Ebay. I added 15 meters of 6mm wire (about $40) as it is essential to be able to chase the sun to get best solar results. A big change from 2004 when I paid $750 for a 64 watt solar set up.