Engel 40 litre, aproximate amps used a day

Compressor fridges should cycle 1 to 1 so 12 Hours in 24 and that is at 25oC.

A 39L Engel is supposed to use 2.8A per hour so 12x2.8 =33.6 AH per day.

As the ambient rises the fridge may still draw what it is supposed to but will run longer to get the heat out of the fridge walls and some fridges in high ambient can end up running 24/7.

Travelling dayly and with charging from your vehicle you can start with solar at 60W and for every day you stay camped you can add 10W untill you get to between 120W and 160W to give you 24/7 power from solar depending on how efficient your fridge is.

Charging two batteries in parallel does not necessarily mean you can cut the run time down by half to effectively charge them with the 80A unit and any time gained would depend on the battery type and its resistance.

Two six volt batteries would give you better capacity than two 12V and has the potential to charge better and give a better draw down facility.

DC Smart charging would cut down run time similarly too would high recombination AGM or GEL Batteries and be careful with that aspect as all AGM are not capable of that aspect.
Ian

60 AMPS to run two fridges of dc is about right.... and your exactly right about $$$... imho go solar and babysitting your system will never end, unless you have a small retirement fund of course...

BPsolar is british petro', so i bought the ef1000is. I am sure it will run two engels on 240v in eco mode but i am not so sure it would handle the 2 x 12v invertors.

as to your neibours, they wont notice the sund og the genny if you point it right and they prolly want to get one of the EU10's being advertised on tv anway...

Hi KWK

Most DC fridges have a duty cycle of 30 to 40 % and at an ambient temperature of 30 degrees day time I would expect you to use 25 to 30 amps per fridge per day.

How many days do you stay in one spot ?

Running 2 fridges I would recommend at least 2x 100 a/h batteries and approximately 160W (2x 80W) solar power. This would make you almost self sufficient.

If you used a smaller panel like the 100W Bi-Fold and 2x 100 a/h batteries you would fall short about 10 amps per day and could only stay in one spot for about 10 days before needing to charge via the car or generator.

Hope this helps.

Regards

Derek from ABR

I have two 40 Litre Engel fridges in the back of my 79 Series, so probably a similar set up to what you are planning.

The new 40 Litre Engel is rated at 2.5 Amps. I have checked it with a clamp metre and it is spot on. Assuming 50% compressor run time, that gives exactly 60 AH per day. In my experience, the BIGGEST impact on compressor run time and power consumption is ambient temp. But these figures are reasonable for planning purposes.

You don't say if you use your batteries for anything else (lights, charging phone, camera, etc). My thought is that for the fridges alone, 100AH is a bit low. If you use the batteries for anything else, I would certainly add a bit more storage capacity.

In my vehicle, I have a 90 AH AGM in engine bay and a 120 AH in the back with the fridges, so a total of 210 AH. Perhaps more than necessary in most circumstances, but I transferred the batteries from my previous vehicle. Also, I always have one of the fridges (sometimes both) set on freeze.

For charging, I use a 100 W Bifold panel (purchased from Derek Bester at ABR, an advertiser on this site). This works well, but does not supply quite enough power to replace what I use. I reckon I fall behind at the rate of about 20 to 25 AH per day. This is not a big problem for me, but could be easily solved by adding another panel. I currently solve the problem by:
- minor 'admin' driving of the vehicle every couple of days
- connecting the vehicle to the van, where there are 3 x 130 W panels charging the van batteries.
-occasional running of the generator at a time we might want to use it for other purposes like running washing machine in van (yes I know, over the top, but the van is soon to be our home for a few years).

Long story, so to summarise. One battery and one panel is adequate (just) if camping for just a day or two, but I reckon you need a bit more battery storage. With an extra battery, one panel will keep you going for 2 to 3 days, depending on conditions. If you want longer time without running vehicle or generator, another panel will need to be added.

All just my view, based on my experience. Hope it helps.

Norm C

They did a comprehensive test some time ago & the Engel 40 litre averaged 1.6 amps per hour.

kwk56pt

we are totally dependent on solar and our set up is is follows

60L Engel as Fridge + 40L Engel as freezer.......2 X 100ah AGM....charged by vehicle alternator when travelling....(have a spare 100ah under bonnet but never used it for the fridges)

4 x BP 80 watt panels....we never run out of power! The simple explanation for 4 panels is that I have them in two hinged pairs.

we like to spend time out walking away from camp and so I set one pair up facing the morning sun and one pair up to pick the sun for the afternoon..........that way I dont need to manage the panels by chasing the sum and shifting several times a day if we are in shady areas.......

bottom line is that with my set up 2 panels + the 200ah battery reserve is adequate.........I chose to purchase the extra couple a few years later......definately not essential..and my experience on power usage is along the lines of the majority of the answers you received...........ball park figure work on 40 to 50 ah per day per fridge unit depending on the ambient

cheers