Engel 40 litre, aproximate amps used a day

Submitted: Friday, Jan 30, 2009 at 23:45
ThreadID: 65553 Views:17613 Replies:6 FollowUps:16
This Thread has been Archived
Trying to do some calculations. Is 60 amp hours per 24 hours a realistic estimate for 2 engel 40 litre fridges located in shade working at 4 degrees in ambient temps of around 30 degrees

I am thinking solar mainly to be a considerate neighbour I have a honda powered 80 amp alternator ( yes I know the noise) and one 100 amp agm battery It all worked fine last year but it did need two 45 min charges a day.
I am undecided as to whether to get two 90 amp lorentz panels or one panel and another 100 amp battery which could reduce the run time to 40 mins a day done in the morning as it will charge two batteries as quick as one or is even 40 mins unacceptable to most people

Even with two panels there will be a defecit I think. The batteries are secure in the vehicle and panel or panels not so secure and looking infinetly more attractive.So whatis your experience or opinion should I be thinking two panels or one and another battery or abandon the charger ( it was home made cost about $550 ) and go the quiet invertor / generator and three stage charger. Of course the extra battery, yamaha genny and two solar panels would be the ideal set up but $$
Back Expand Un-Read 0 Moderator

Reply By: RV Powerstream P/L - Saturday, Jan 31, 2009 at 04:50

Saturday, Jan 31, 2009 at 04:50
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.

AnswerID: 346821

Follow Up By: RV Powerstream P/L - Saturday, Jan 31, 2009 at 04:55

Saturday, Jan 31, 2009 at 04:55
The last paragraph would be better read
"not all AGM are capable of that aspect."
FollowupID: 614879

Follow Up By: kwk56pt - Saturday, Jan 31, 2009 at 12:25

Saturday, Jan 31, 2009 at 12:25
hi, the run time for the 80 amp unit to charge one 100amp agm battery is about 1 hour. With two batteries it will still take one hour. I was thinking this could be done once a day instead of twice which would halve the run time.
If I didnt buy a battery but used one 90 amp panel this should meet the needs of the fridges during the day and I would need to run the charger in the morning for about one hour although it would probably be better with two batteries.
I thought the one battery and one panel and oine fridge would then be fine for my other touring camping holidays. I have to admitt I am not as enthusiastic as I probably need to be at throwing money at this. Not retired so its use is limited.
The battery life will be shorter as it is discharged deeper than with two but then again I at the moment need only replace one.

Would one panel and another battery be a better choice than two 90 amp panels if you were working on a budget ?
FollowupID: 614918

Follow Up By: kwk56pt - Saturday, Jan 31, 2009 at 12:31

Saturday, Jan 31, 2009 at 12:31
Hi, should have mentioned I normally travel with one fridge but as we are camped for four weeks at Ningaloo again this year will take two fridges
FollowupID: 614920

Reply By: robertbruce - Saturday, Jan 31, 2009 at 09:52

Saturday, Jan 31, 2009 at 09:52
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...
AnswerID: 346843

Reply By: ABR - SIDEWINDER - Saturday, Jan 31, 2009 at 09:56

Saturday, Jan 31, 2009 at 09:56

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.


Derek from ABR
AnswerID: 346844

Follow Up By: kwk56pt - Saturday, Jan 31, 2009 at 11:58

Saturday, Jan 31, 2009 at 11:58
Thanks Derek for your reply. Normally travel with the one Engel but this trip we plan to be camped at Ningaloo for four weeks and as it is reasonably remote I take the two fridges. The 80 amp honda was cobbled together with the 100 amp agm battery as a relatively inexpensive way of providing power as I was not sure how much of this type of camping we would do. Last trip I would charge the battery in the evening and again in the morning but it probably would be better with two batteries.
FollowupID: 614915

Follow Up By: ABR - SIDEWINDER - Saturday, Jan 31, 2009 at 12:06

Saturday, Jan 31, 2009 at 12:06
Yes your best and cheapest option for this trip would be to simply purchase a 2nd battery to match the one you have, join them with heavy cable and they will charge quickly off the 80A Honda.

I would say 2 - 3 hours a day would bring them back up.
FollowupID: 614917

Reply By: Member - Norm C (QLD) - Saturday, Jan 31, 2009 at 09:59

Saturday, Jan 31, 2009 at 09:59
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

AnswerID: 346845

Follow Up By: robertbruce - Saturday, Jan 31, 2009 at 13:18

Saturday, Jan 31, 2009 at 13:18
Norm, can I ask if you have had to replace/upgrade much of the componetry since it was ramped up for you?
FollowupID: 614930

Follow Up By: Member - Norm C (QLD) - Saturday, Jan 31, 2009 at 13:23

Saturday, Jan 31, 2009 at 13:23
Sorry, but I'm not sure which components you are talking about. Do you mean the suspension upgrade?
Norm C
FollowupID: 614935

Follow Up By: robertbruce - Saturday, Jan 31, 2009 at 13:31

Saturday, Jan 31, 2009 at 13:31
OMG, I forgoten allll about that one...I8)
FollowupID: 614938

Reply By: Shaker - Saturday, Jan 31, 2009 at 12:05

Saturday, Jan 31, 2009 at 12:05
They did a comprehensive test some time ago & the Engel 40 litre averaged 1.6 amps per hour.
AnswerID: 346862

Follow Up By: robertbruce - Saturday, Jan 31, 2009 at 13:40

Saturday, Jan 31, 2009 at 13:40
those tests used constant supply 80amp powersupplys run off 240 Volts to power the test subjects continusly...to me this seems hardly like being out in the bush with a real-world budget
FollowupID: 614940

Follow Up By: Shaker - Saturday, Jan 31, 2009 at 15:03

Saturday, Jan 31, 2009 at 15:03
They also varied the ambient temperatures quite considerably.
FollowupID: 614964

Reply By: Member - bungarra (WA) - Saturday, Jan 31, 2009 at 14:37

Saturday, Jan 31, 2009 at 14:37

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

Life is a journey, it is not how we fall down, it is how we get up.
VKS 1341

My Profile  My Position  Send Message

AnswerID: 346880

Follow Up By: kwk56pt - Saturday, Jan 31, 2009 at 16:05

Saturday, Jan 31, 2009 at 16:05
Thanks for the reply, so when you spend time out walking away from camp you just leave your panels out sunbathing themselves. I am not confident I can leave my garden hose out the front of the house but some how it seems people can leave the odd thousand or two worth of solar panels out. Cars are broken into every day for nothing more than change in the glovebox or a sat nav unit.
I think thats why I have been reluctant to get the solar. So do you secure them in anyway. I have read on this forum of people leaving them out while away from camp, why they dont go missing is a mystery to me.
If you only had one panel wouldnt just facing it north catch the bulk of the sun or do you think moving it around would make that much difference ?
FollowupID: 614992

Follow Up By: Cram - Saturday, Jan 31, 2009 at 16:12

Saturday, Jan 31, 2009 at 16:12
It's a big relief to have plenty of power and options. After struggling in recent times I purchased a 100w bifold panel from ABR.

I now have 2 x 110amp hr batteries totally devoted to running the 60litre engel and a 100amp hr to run the fluros etc.

All of these batteries are able to charge via the vehicle.

In good conditions this month I have been able to stay put in the bush for 5 days. My battery has stayed topped up and the fridge has run no problems.

I have a large wire cable to secure the solar panel when we are away from the camping site.

My next option is to buy a smal gene so I know I have all bases covered in all weather conditions.
FollowupID: 614993

Follow Up By: Member - bungarra (WA) - Saturday, Jan 31, 2009 at 16:42

Saturday, Jan 31, 2009 at 16:42

Yes mate I leave them out "sunbaking all by themselves".........in the first few years we were concerned about security but then it interfered with being out the bush enjoying ourseleves and not game to stray too far from camp!...so we gave up and trust to the basic fact that people out bush are as honest as us.........

we work on the theory that firstly they are quite cumbersome and so a spur of the moment decision to pinch them will cause some headaches where to stow them.......as for premeditated theft you will simply never defeat that......... secure cables, padlocks etc they will be prepared for all of that...........

in answer to your question of facing the sun............you do need to manage your panels...........it is not as simple as one set up and forget......the sun travels around and your panels do need to be turned and following several times a day if you wish to maxmise them effectively......dont be mislead into thinking there is 8 hours of effective sunlight and therefore 8 hours effective charging....simply does noit work like that....moving them to keep facing the sun is the difference between charging and not charging...simple as that

Life is a journey, it is not how we fall down, it is how we get up.
VKS 1341

My Profile  My Position  Send Message

FollowupID: 615000

Follow Up By: kwk56pt - Saturday, Jan 31, 2009 at 17:20

Saturday, Jan 31, 2009 at 17:20
Ok, didnt realise that more effort than I thought is required to maximise the use of the Solar Panels. Yes you must be right in that most people in the bush are honest. Nice looking body on your Toyota, is that a Bosston canopy and is there anything you wish you had done differently It looks like a two door, maybe you regret not getting a 3 door. Your tray looks like the standard 2400 X 1800 , I mean you didnt have it made any narrower ? I think the trayback and box canopy is a good combination and plan to get one myself.......Cheers Peter
FollowupID: 615010

Follow Up By: robertbruce - Saturday, Jan 31, 2009 at 19:37

Saturday, Jan 31, 2009 at 19:37
try to use one of those fancy unsymetrical chains to tie down all your stuff, they are hard work for bolt cutters ... even chain stuff up in the car.... usually thiefs cant afford bolt-cutters or they are in the hockshop. If a thief can afford bolt cutters your going to loose everything anyway ... at any rate, consumables are more likely to go missing, like beer... I have a booby-trapped steel lockbox for them, most precious's'...

in my last two years of travelling there have been
...two unsuccesfull attempts on genny, both city areas..
...one successfull attemp on my tarp bag, total loss was $40, that was in canberra CBD
FollowupID: 615041

Follow Up By: Member - bungarra (WA) - Sunday, Feb 01, 2009 at 16:20

Sunday, Feb 01, 2009 at 16:20

Yes it is a Bosston but it is also a 3 door. It is on a 2400 x 1800 size tray........but nothing is standard

The steel tray was constructed to my specifications as far as strength and quality goes......not satisified with the run of the mill light weight things that are common

As for the canopy I had Bosston construct it specificaly to my purposes....long radius........3 doors but the side doors are a little longer than normal (probably why you thought it was 2 doors).......as after many years of making do in other tray top set ups we knew exactly what we wanted to fit and where inside........in other words the canopy was designed to house a pre determned "floor plan" down to the last cm.......likewise the rear door a place for everything and everything in its place....so when we got the empty canopy back home I spent a few weeks fitting it all out.........much fun and satisfaction

I am pleased to say that I would not change anything at all on the design


Life is a journey, it is not how we fall down, it is how we get up.
VKS 1341

My Profile  My Position  Send Message

FollowupID: 615220

Sponsored Links

Popular Products (13)