Best size <span class="highlight">solar</span> <span class="highlight">panel</span> for a 100 amp 2014 outback

Just all the standard gear in them, lights etc.what is it best to run the fridge off? Gas or the battery?

Jason, when you are stationary and camped, you would be better to run your fridge off gas.

If you are new to the game, there are a few things you need to understand and learn about DC power and it's a little more complicated than simply buying a panel and hooking it up (not too much but it would be clever to know what your needs are in the power consumption stakes, what type (AGM for example) and size battery you have (100 A/H etc)). Could I recommend that you have a read of this blog. It will be a great start on your path to DC guru-ship.

Electricity for camping

For solar panels have a look at Bitdeals on Ebay. Good product at reasonable prices.

Cheers

Mick

Awesome , thanks for your help, appreciate it. Will have a look.

What kind of fridge, Jason? Compressor, two or three way (impractical on 12V except when driving), and how cold? IE, are you using it as a fridge or freezer? That affects power consumption hugely.

It is a 3 way fridge, 94L. The problem is I haven't got the van yet I don't pick it up till next Friday.
It has the small freezer in it as well I believe, it is like a bar fridge set up I believe.
LED lighting in the van. I saw on another reply I need to do a total on amps going to be used with lights, fridge, chargers, Ipods etc.
It has a 12 pin set up as well, so I am getting my car sorted for that. it has the 100amp deep cycle battery in it.

Jason,

A three way fridge that runs on 12V, 240V or gas, right? If so forget about running it on 12V while camped - it draws too much current and there is no practical solar setup that will keep up. Run it on gas.

The 12V side, properly set up, can be used while driving. The fridge probably draws about 15 amps on 12V, so it need good cabling from the power source (start battery), back through an Anderson plug to the fridge itself. The cabling must be big enough to cause only a minimal voltage drop under the 15 amp load.

You need at least 12 full volts under load AT THE FRIDGE.

When I did mine I used 6 B&S all the way and I'd recommend that for you. Some people suggest 8B&S (smaller) cable, but IMO that is marginal, especially on a long cable run in a big van.

That leaves the rest of your van electrics to be accounted for. As other replies and follow-ups have suggested, work out your power consumption and from there we and you can work out how much solar is advisable.

Cheers

Jason,

"It has a 12 pin set up as well, so I am getting my car sorted for that. it has the 100amp deep cycle battery in it."

What is your car? IE, does it have a steady 14 point something volt alternator output, or is it one of the newer ones with a low voltage charging system, down to as low as 12 point something.

If the latter IMO you will need a dc-dc charger in the van, which will boost the low voltage from the car up to a suitable level to charge you van battery. In fact, I would do that anyway because you get a charge tailored to suit your deep cycle van battery. I'm sure you will read contrary opinions here, so I'm just saying what I would do.

The average retail sparky will run undersized wire to the 12V auxiliary pin(s) on the socket. Ditto the van manufacturer will likely provide undersized wiring from the 12 pin plug to the van battery.

To run a 12V charging system in your van I would use minimum 8B&S from vehicle battery to 12 pin socket and from the van's plug back to its battery or dc-dc charger.

Also the 12 pin flat connector won't take the big cable you need for the fridge. That's why I mentioned the Anderson - it needs to be on a separate circuit, IMO.

If you haven't already done so, you should consider an isolator so that Auxiliary power to the two sockets (12 pin and Anderson) is switched off when you switch the key off. Without it, if you park your car and van and go shopping the fridge and the dc-dc charger will continue to be powered from your car battery and you'll likely return to a flat battery.

Cheers

I have a Kia Sorento 2013 model, yeah my parents told me to get an isolator as they got stuck with that exact situation. I am getting the socket put in next Friday so I will make sure I get the 8B&S, so I should get the Anderson plug to then to run the Fridge while driving?

I had a Sorento some years ago - a great little vehicle and quite under-rated by the 4WD cognoscenti. I towed a CT with it on some pretty awesome tracks. I set it up just as I have posted above.

Power from Battery to isolator. From the output side of the isolator, two runs of cable, one being 8B&S to the aux pin(s) of the 12 pin flat. The other, 6B&S to the Anderson. The negative of the Anderson should go to a good chassis earth. The chassis earth should be bolted, not just a terminal screwed with a self-tapper to some sheet metal. And polish the metal before connecting, then when you're finished cover the connection with anti-rust gunk.

"so I should get the Anderson plug to then to run the Fridge while driving?"

Yes, exactly. If you follow this plan you will have to run 6B&S on the van to where you can access the 12V supply to the fridge and join up there. Same thing with the van's negative - 6B&S from the Anderson to a bolted chassis connection and sprayed with gunk.

The 12 pin flat on the van should have matching 8B&S from the aux pin to the battery or dc-dc charger. I THINK your Sorento has a fairly high alternator output (you'll have to check), so you MIGHT get away with no dc-dc charger, but I prefer to put one in. If you choose the right brand it can double up as a solar regulator, which you will need when you get your solar requirements worked out.

Cheers

Jason,

Sorry to be doing this in bits and pieces, but Swampy made a good point in his reply...

If you run 6B&S from an Anderson back into the caravan for the fridge you can branch the battery charging off that and you won't need to run the 8B&S from the 12 pin flat plug.

So is that as simple as looking at the fridge & it giving you the amps usage or do I need to power test it while it is running?

It has a 100amp deep cycle battery in it at the moment.

Pretty much yes. The labels on the gear will give you the info you need. The fridge label may tell you it draws say something like 4 amps or 48 watts but thats only when the compressor kicks in so is worst case.

Once you know your max power consumption, you need to allow extra capacity for future gear, panel inefficiency plus weather. Clouds etc will drop the generating ability of the panel significantly.
Its all about what you can afford but I allow 50%-100% extra in the panel. If your wattage comes out at say 100 watts then try for a 200 watt panel. 200 is a very common size and due to the demand, pricing is pretty good.

You then need to get that power into the battery.
Most decent panels have a built in MMPT controller. You cab google these but essentially its a smart controller and optimises the panel output so as to provide the best charge to the battery. Its a 'must have' so make sure one is one the panel otherwise you will have to buy one.

The whole 12v battery / solar thing is going to screw with your brain a bit as you learn all this stuff :)
Not all batteries are created equal. Just because you have a 100A deep cycle does not mean you will pull that current for long. Some batteries (Optima Yellow Top for example) will let you flatten the battery a whole lot more before losing output. Depending on how you want to use the vehicle determines the quality level of the battery. ie spending 3 weeks in the middle of the Simpson dictates an Optima whereas a weekend away will likely only need a cheap Chinese thing.

Ok, so far you built yourself a solar charging system for your camper battery.
Now to complicate things even further, what about charging when you are driving. Have you thought about getting your trucks alternator to charge the camper battery?
Everything mentioned above still applies and your camper should remain a 'stand alone' system but you can add other gear to connect this to the truck power as funds permit.
This will start off a bleep contest with makes & models but you'll need to do your own research to cut away owner emotion from reality.
What I have is a big fat (6BA at least, bigger the better) cable running from the truck battery (the Aux one if you have two) to the tow bar where you terminate it into an Anderson (see Ebay) connector. The camper plugs into this and that cable runs back to your battery(s).
There will be a voltage drop down all that cable which will prevent the alternator ever charging the camper battery correctly (the bigger the cable the less drop). You need a DC-DC converter / smart charger to boost that voltage and charge the battery correctly.
Also, depending on your hardware choice, the DC-DC charger should be able to take the output of the solar panel and automatically switch between them as conditions permit. For this I use a Ctek D250s-Dual. Its an awesome piece of kit but you will be bombarded with opinions on other gear as well. If you use the Ctek, it has its own MMPT controller built in so if your solar panel has one, you'll have to bypass it (dead easy).

So now you have a system that can charge the camper whilst you drive and a stand alone camper that charges via solar.

Hope that helps a bit :)

Good post swampy. Covers all the bases.

Hi Jason, I am in the same boat as you so this is an interesting post .
I have a camper with a 90 AH battery that is fairly old, it powers a series of LEDS inside, a waterpump and a led strip light for the annexe . This setup came with the camper and works well for what it is . I don't have a fridge in the camper and never will so it will be fine.for a week or so as long as we take it easy on it .
Here is what I don't understand, Here is the crunch question for those recommending a big amp charger for 240 volt home top up ? I have been monitoring it while in use and while sitting at home with no load with a multimeter and only thru leaving a light on inside for 3 days straight by mistake it hit 12 volts ( only had it a month at that point so was checking regularly ).. In this time I have only used a Ctek 4 amp to recharge only cause I had one sitting here. Seems to work fine gets it up to around 13.8 volts on bulk and when finished in 12 or so hours goes to float mode .
Went away last weekend 2 nights and came home with 12.59 volts .
Prior to this I purchased a Arkpak and 120 AH battery which is sitting in the shed from a specialist 12 volt shop, in the course of the conversation I asked whether my puissant 4 amp charger was a suitable tool for recharging an AGM battery. You will have to buy a big dollar you beaut 300-400 dollar one was the answer .
I may be stuffing my battery up by doing this but being a unknown quantity to begin with I thought I would try it out anyway !
I have also purchased a Aldi 120 watt panel with a basic regulator and have not taken it away yet .
Testing at home on said battery has revealed it works ok but the jury is out still.
Having said all this we don't venture all that far from civilisation but like to stay in national parks which only last up to a week or two. If I was relying on a 12 volt system to keep the beer cold in far flung areas I would invest a heap more I suppose .
My point ? Do you really need to outlay all that dosh when you have gas on tap for stationery use ?
P.s the advice about hard wiring is spot on, that area is never a place to skimp on .

A mate at work got the German made 160W solar panels from Bitdeals & rates them highly, has the MPPT built in & guarantee waterproof, has the fold out legs, he said the bag they came in is quite protected, so was going to check them out & do a bit of research on them. Know of anyone that has had any issues with them? If you look at items sold they are way above everyone else with items sold.

Jason,

It is better to have the regulator close to the battery with short leads to the battery. You can then have long and smaller gauge leads from the regulator to the panels.

Panels that have the regulator built into the back are convenient, but the long lead length to the battery is a real compromise unless you decide on heavy gauge (like 6B&S) which is bulky and heavy.

Additionally, with a separate reg you have a wider choice of REAL MPPT (swampy alludes to false marketing by cheap Chinese products), you can permanently install it in your van so weather proofness is not an issue.

My recommendation is to shop around/seek advice for quality panels with no inbuilt reg and do the same re a separate MPPT regulator.

And just a reminder - I said in another reply or follow-up here that if you choose to use a dc-dc charger, (which I think you should) then consider one that has inbuilt MPPT as well.Redarc make a good one. You can get these much cheaper on eBay. Ctek has one, but a number of people have reported poor solar performance with them.

The Redarc will have sufficient capacity to address your needs and also allow for expansion if you choose more battery capacity and more solar at a later date.

Cheers

hi Jason f71
Bit deals on special 180watt trifold $260 same as 160watt double fold wow
Check out Sunyee also.

The only issues I have read on the net ,catches not working ,zips in bags not working ,cable lucky to be 6mm sq. in size .Warranty claims from bit deals seemed an easy process .
If u run large long cable to panels have a connector at each end [disconnect completely] so u can roll it up like a domestic cord. Cable should be around the length of camper 6-8mtrs .
These are the panels i would have if they would have delivered to the far north.
I have 1x 195 portable with a pwm controller that can be used or bypassed
1x 195 soon to be fixed to roof
both panels connect at drawbar
wired to mppt [e tracer 30 amp ]charge controller mount in the front boot of camper

swampy