solar and batteries

Hi
For long battery life the 100ah bat should not be discharged below 30% of its capacity[max ] ie70ahs usable capacity.
Depending on conditions of use[ as in other post ], the fridge could easily "RUN "for 12+HRS PER DAY[ ie actually use 42+ahs per day.]
Without make up input from solar the bat will be @ its max recommended discharge limit in 34 hrs.
Solar on a good day gives max ouput for about 6hrs if in a flat position, this can be improved if the can be regular repositioned to face square to the sun.
A 80w solar will give about 27 ahs input on a good day, so allowing for losses you would need min 2x80watt panels [I would suggest 2x100w as a safer margin to make up charge used over night ] to keep the bats near full charged ready for that /those cloudy .rainy days.
I would also suggest you get a low voltage cut out [ battery
discharge protector] to prevent you accidently over discharging
the bat & thus shortening it's life.

thanks motherhen isnt it easy to be confused from 160w maybe not enough t o 80 w running well great to hear from you because you were out there using something simular to what i have and the newer engels are even more efficent

Yes, i don't get into the technicalities, and leave that to some of the members here who are in the trade and willingly share their knowledge.

Our panel works for our old style Engels which may not be as efficient as the newer models. The Engel in the caravan was different, being a traditional style upright caravan fridge so wouldn't have the same efficiency as the car fridge style. It would depend on climate and region you will frequent.

We'll see how it handles two batteries. If not - easy to disconnect and go back to one. We generally tour with the Bushtracker, which is set up with four panels. We are getting four new Full River batteries from Challenge Batteries (as mentioned above) tomorrow to replace the three which are insufficient for four 130 w panels. Two of the previous have graduated to the F250. We generally only camp away from the caravan for short periods.

Mh

Hi all
I have a simple thought for most 12V fridges starting with small chest type.
If you travel every day allow 60W of panel and then add 10W for every day you stay stopped until you have between 120W and 160W to run off solar.
Then consider your use and upsize further to cover the size of fridge and efficiency knowledge gleaned form actual use.
This was told to me by an old bush fridgy with a lot of experience and I believe it works well.
So for what its worth consider it.
Regards
Ian

thanks brian i went to abr site looks like a good panel what size battery are you using thanks again

Yes we have the same - 100w bi-fold panel - also bought from ABR. More than ample - we use it in the same manner as you have described.

sorry mainly sounds like another expert said a lot told me nothing what i want is quality panel ? w agm battery ? ah perfect weather in north queensland sun not a problem 1 fridge nothing else shouldnt be hard for an expert using built in regulator portable panels

How good as in "how much quality" can you afford? and no, I don't expect you to put a $$ value here at all !!
but the thought 'buy the best you can afford' is relevant.

Look at what their advertising states and does NOT state !!
That's a very good clue to start with !!

I swear by the brand, "type" and "model" of panel & Solar regulator I use, because I had a choice I selected the panel I believed worked better when laying flat and working in very low light conditions too as you don't get perfect sun conditions every day or in shady areas either.
I choose the Solar regulator that is fully optioned and worked with my system showing me what's happening to my batteries and charging system instantly.

With batteries, get an AGM DC that has the connections that 'don't' look like normal car batteries, because you don't want a normal battery, you want a specifically set-up and designed AGM Deep Cycle battery to store and then release power efficiently.
My batteries look 'different' because they are different, but if you connect them with cheaper, thinner cables you will loose all the benefits you have paid for, so don't go down that road.

The tech stuff & pics with their individual explanations on my 'profile' tells it as it is for me, so no requirement to repost here, as it's many pages long :-))

BUT.. you may want more or less battery power, larger or smaller capacity solar system, just because it is specified for my use does NOT mean it will suit your use, it is only there as a general purpose guide.

Mainey . . .

Victorwindus,
You say “expert say a lot tell you nothing”
So some very direct questions for you
If your not prepared to answer them
I’m sorry I can’t assist you further !!

(1) "how much quality" can you actually afford ??
YES, if you need detailed information, I need a $$$ number !!

(2) How much roof or storage space do you have? (for storage of Solar panels)

(3) How much space do you have for storage of AGM batteries ?

(4) What is your post code ??

Mainey . .

Hi Mainey
I don't know about postcode but it seems Victor is in NTH QLD.
Better ask is he is going summer or winter camping , some big differances in frig run time possible, especially if lots of warm/hot beer going in.
It does get overcast & RAINS for days on end EVEN IN QLD
Also if he intends to camp for<10days without any charge for batts other than solar what is he going to do if overcast weather sets in after a few days+ answers to all the other factors that we still do not have in order to access a possible min requirement of solar & bats
.
As you & I & some others have said LOTS of factors to consider.
But the simple answer may be get as much bat cap & solar cap as he can fit & afford, but that is obviously not the answer he wants.

Hi John
NOW that's what I mean when I said detailed info.
I don't need to tell you that you need lots more bat & solar capacity if you intend to use it camped for a period of time.
Hopefully with the info posted you can get some idea of what you need.

Yes I need to find Lasseters cave.
Its the only thing that`ll save me from $ ruin.
John

John,
another problem you have is the wetcell battery, whatever the brand (is not relevant to this advise so it's definitely not brand bashing) will take much longer to recharge than an AGM battery, this stops it getting fully charged in the same period an AGM would have fully charged, due to the much lower internal resistance of AGM batteries.

This is a reason large Solar grid systems use AGM batteries and not wetcell batteries.

Mainey . . .

hi oldtrack123 personal decisions cost money thats why we ask for advice you used the word expert with inverted commas ''experts'' the inverted commas highlight the word to knowall the true expert the one with real personal experience are the greatest asset any forum can have

Hi Victor
Read reply 9 to post 8. [15yrs practical experience with this one & many previous set ups]& yes an expert ,tecnically qualified.
Making such a decision on other's advise [ even if it is their personel experience ] can also be very expensive unless your conditions of use are identical,& you nor many of the other posters have clearly & FULLY detailed their CONDITIONS OF USE, Just as you have not clearly & fully stated your intended conditions of use. [ie how many beers a day do you wish to chill ,is it only to maintain fridge temp 3<4c etc]
Nothing worse than warm beer or all the food going off, due to an incorrect decision based on insufficient detail.
If you want the simplest answer to your question buy a BATTERY CHARGING GENNY,then you can run it when ever your batt falls to the 30% charge level. probably ok in most bush camps, but use may be heavily restricted elsewherelIE nat parks & where others are camped]

oldtrack conditions may not be identical but somewhere there must be a happy medium as for my conditions of use fridge in caravan normally under big tree on bank of river between ravenshoe and normanton between may and september need solar for fridge only nothing else no kids opening fridge my wife and i dont drink always perfect weather other wise go home want to rely entirely on solar been whinging about noise generators for years dont tell me there quite now and and as many panels and batterys as i can afford and carry is not what i want to hear i want portable panel fridge has low battery cutout on it i dont know how much more detail you expect

oldtrack conditions may not be identical but somewhere there must be a happy medium as for my conditions of use fridge in caravan normally under big tree on bank of river between ravenshoe and normanton between may and september need solar for fridge only nothing else no kids opening fridge my wife and i dont drink always perfect weather other wise go home want to rely entirely on solar been whinging about noise generators for years dont tell me there quite now and and as many panels and batterys as i can afford and carry is not what i want to hear i want portable panel fridge has low battery cutout on it i dont know how much more detail you expect

"dont tell me..... how many panels and batterys as i can afford and carry is not what i want to hear i want portable panel fridge has low battery cutout on it i dont know how much more detail you expect"

victorwindus, You have a gr8 time on the river bank !!

Obviously I can't assist you in any way :-((

victorwindus,

Up higher in the thread I asked for your "post code"

I did this ONLY because I probably will know a company or have a contact specialising in Solar systems & 12v batteries, in your own local area that will/could assist you direct @ mates rates, but never mind I will say bye and hope your travels are safe.

Mainey . . .

I would be really interested to see a real and factual report from the
main fridge companys , in relation to #10 .
I read all the great..... it only uses **per day @20` odd statements,
but real usage in Oz bush outside of a southern winter from these
companys would be good , if not even a little honest...
I have seen a few mag reports , but not what I call informative.
No wonder a lot of folk have gens rattling in the bush , not just to
feel as if they have company/neighbours,its to keep the ice cream
going runny at any cost.Solar ice cream must be about $22 a cone
at a quick guess.Have to go back to only cool beer and cans of
spammmmm.

John

Hi Victor
But now you have given a little more detail.
Camping in dry season, [COOLER ], little likely hood of clouds.
Fridge apparently mainly for food storage @ 3<4 c[ don't know if you may be catching fish to freeze ,that would put a heavy load on bat so will ignore THAT as a requirment.
Also don't know where you have or wish to have aux bat fitted.
Also if weather does change prepared to pack up.

A 80w panel will only just supply enough power to run fridge for about 12hrs per day based on fridge motor actually running 50% of the time,the other 12hrs will be drawn from your battery,which needs to be recharged during the day.to do this with a small margin of safety I believe you would need 2x80w panels in parrallel [1x120w may manage IF you wnted to try that out ]. You could get a 40W later if you found you did not have enough.

Now with anything more than a 40w panel connected to a battery you SHOULD have a regulator to prevent the batt being overcharged &/or high voltages in excess of 15v being feed to the fridge possibly causing serious damage.
The cable from the panels to the bat SHOULD be as short as possibble as it intoduces loss [ ordinary heavy extension lead up to 10m max would not be too much of a problem]
The solar reg SHOULD be fitted as near as possible to the bats but not in same compartment.[damage from fumes]. AS I pointed out in my early post constant repositioning to track the sun from dawn to dusk is definately worthwhile if you are using min solar panels.Also adjusting the thermo to get everything as cold as possible [without freezing the lettuce etc] during the day & turning it back to a warmer setting overnight [to reduce demand on bats o/n] will also best utulise the available power. While AGM bats may be superior in some respects I think that since you are looking for low cost & simplicity I would use deep cycle wet lead acid bats.
Get a hrdrometer , to check their state of charge & carry some distilled water to top them up.
Hope this helps you, it may not be the perfect answer, you will just have to see how it goes under your condition ofs use

HI Victor
one other point , the low voltage cut out on the engel could be @too low a setting to protect your bat[ nomally set for about 11.6v ] I would keep a check on bat spec gravity to just make sure you don't take the bat below 30% remaining charge, if you want reasonably long bat life

oldtrack123 ,you know,I watched tv an afternoon some while back,
SBS I think,and there was this doco on Italian ice cream makers,
and how for some 2 or more hundred years managed to get snow
or ice in the winter from some source, kept adding salt-mixing,more salt ,a little cold water , more salt..etc and it seemed to work
a treat. So in the simpson , one may be able to set up an ice cream
shop for passing folk , whom fridges have not..........,and flog em ice cream and cold beer.just frost up a freezer tub-scape it out ,add
lake eyre(or even WA wheatbelt ) salt (or any salted paddock)
and presto
Waeco and engel look out
John

oldtrack123 thanks for the positive feedback id like to pick your brain a little further regards battery it will sit on caravan drawbar i was thinking sealed wet cell acid deep cell battery are there any advantages in the sealed type? i shall take your advice and have a low voltage cut off fitted regards panels whats your feelings on the fold up panels with regulator fitted some one told me i should buy 2 panels and make them foldable myself or some sellers make them up for you than use a better quality regulator and battery i was thinking 120ah do you think that would be sufficient we do fish and catch redclaw but only for the days needs love beef gotta keep that cold thanks

Hi Victor
Many differant views on best bat type but sealed / low maitenance deep cycle bats personally dont appeal to me.I have h found wet cell that you can check with a hydrometer & add distilledwater if required are more reliable& easier to check for faults. AGM & gel bats are superior in charge & discharge capabilty but you pay for it, they also should not be mixed with wet lead acids on same charging circuit [ have different requirments].
You would need to look at the weight of 2x80w folded panels & if you can store & handle them ok.I have not looked @ market available folded panels so on that I can only suggestyou have a good look @ what is avaiiable.
Fold up panels with the reg fitted @ the panels WILL get a false indication of bat state of charge[especially if used with an extension lead] will think bat is fully charged before it realy is.[ see what I isaid about having reg as near as possible to bat].
If you are a handy man no real reason why you could not make up a folding set , again suggest you try to have a look at some panels to see what is involved.
Bat size ?? O'DEAR now I want to become an "expert" again but I wont
I would just say that 120 a/h would be the mininum I would consider even that could give the bat a bad time[ bat life is based on depth of discharge x number of cycles the deeper you discharge it & the more often the shorter its life]

"love beef gotta keep that cold'" REMEMBER THE FREEZER IS A REAL POWER CHEWER,see John's post 10 of 10 for his experience.
I would suggest you get your beef cycro vac packed in meal size portions these can be stored in the fridge section for much longer periods than unpacked , check with your butcher.
Bat on tow bar protected but vented to let hydrogen gas escape .A few hole @ bottom & topof case would be ok.
Do you entend to run fridge while travelling? solar will not be charging so you need to feed fridge from car bat with heavy cable to avoid voltage drop [ could cause under voltage to function]Note also that van bat will not get fully charged & in fact could be heavily discharged if frig is connected to it.& that will start another whole line of comments!! /

oldtrack123 great feedback things are starting to add up i know i will have to do some adjustments along the way but youve been a great help glad you didnt put your expert hat on because that would have been over my head you gave me enough for me to make sense of thank a lot