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Have been looking at 12v compressor fridges for around £450, but having spoke to someone today, they have a 240v tabletop fridge (£80) that uses 68watts of power used with an inverter and have said that they used it for 3 days with no problems (with a 190ah battery)
Any reason why this would not be a good idea ?
 

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Have been looking at 12v compressor fridges for around £450, but having spoke to someone today, they have a 240v tabletop fridge (£80) that uses 68watts of power used with an inverter and have said that they used it for 3 days with no problems (with a 190ah battery)
Any reason why this would not be a good idea ?
Yup. An inverter is a very power hungry & inefficient device. The other individual is using a very large battery. I have a 110ah in my van & it is bigger than my starter battery.
I think it goes something like this:
Wattage required:
68w/12v = 5.6666 amps per hour.

Depending on the inverter, you need to power that as well, so if it uses 100w to run it (most inverter manufacturers don't tell you the amount of power it takes to run it, just the amount it takes to be on standby - my sterling 600w inverter uses 0.5amps on standby):

100w/12v = 8.3333 amps per hour.

Total that up & you get 14amps draw per hour.
Now take your 190amp hour battery & divide it up by 14 = 13.57 hours. It's a bit short of 3 days! Now if the fridge is cycling on & off you may get more time out of it, but due to the inefficencies of the inverter & the fact that the fridge will be in an enclosed space where the rear element s won't work as well as in a house, I would say you would be lucky to get 24 hours out of it. I have just found a website selling a battery that large. It is over £150! See http://www.kernowrat.co.uk/page12.html The dimensions for that battery is 513mm x 223mm x 223mm & weighs a whopping 48kg! The time it takes to charge a monster like that will be quite a while...

I have a compressor fridge, working off of a 110ah battery. Best I got from that is about 2 1/2 days. Worst (very warm day) was 1 day. They are very good on battery power.

Just to let you know. I did consider going down this route as well. I decided against it for the reasons above. If you have to cart around massive batteries, that eat into valuable space inside the van & take forever to charge, just so that you can skimp on the fridge itself, seemed daft to me. Yes it was a painful realisation that I had to spend £400 on a small fridge, just when my sister had spent £300 on a huge brick of a fridge for her house, but I don't regret buying it.
Oh & also for the record, I have been using my van now as a camper for over a year & have yet to use my inverter. I try whereever possible to to use native 12v appliances. It is just more efficient, so you get more out of your battery.
Hope this helps (& I'm off to bed zzzzzzzz):D
 

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Very useful reply as I was thinking about doing this as well A: I will continue to use my 12v cool box me thinks.
Would you agree therefore it would be more battery efficient to keep it plugged into the 12v socket in the bus than to plug it into my 230v inverter via its mains adapter? I can never decide.
Pete. :confused:
 
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