Solar Panel Battery Recharge

[molongmick]

Hi Everyone,
Just wanting to pick your brains.

I was talking to a mate of mine about using a solar panel to recharge/trickle charge the 100amp battery my camping caravan.

The next day he gave me a new 20w mono crystalline solar panel.

I have bought a charge controller from Jaycar which drops the voltage to 12v, as the output on the panel is 17.6v.

Will this set up be enough to trickle charge the battery in the van? The only items running off the battery will be lights, soon to be converted to led, small water pump for the sink and the occasional charge of portable lighting.

The battery is set up to charge while driving, so the battery should be fully charged upon arriving at camp site.

What do you think, will this be enough or do I need more?

[Bigrig]

Hi Everyone,
Just wanting to pick your brains.

I was talking to a mate of mine about using a solar panel to recharge/trickle charge the 100amp battery my camping caravan.

The next day he gave me a new 20w mono crystalline solar panel.

I have bought a charge controller from Jaycar which drops the voltage to 12v, as the output on the panel is 17.6v.

Will this set up be enough to trickle charge the battery in the van? The only items running off the battery will be lights, soon to be converted to led, small water pump for the sink and the occasional charge of portable lighting.

The battery is set up to charge while driving, so the battery should be fully charged upon arriving at camp site.

What do you think, will this be enough or do I need more?

Hey mate - dad has just installed a solar panel for his caravan/battery setup. I can ask him how it's performing for you today and let you know. I'll find out what model etc also to make sure it's a similar setup.

[BillsGU]

It really depends on two things: usage and sunlight. If you start out with a fully charged 100 AH battery and you only use it spareingly, then it should last you for days without any worry. The 20W panel will assist in prolonging the charge in the battery - but at best you are only getting about 1.5 amps out of it. The main problem with solar is that people put their vans in a shed between trips and start out with a less than full battery. Not only does this stuff the battery - but you are always playing catch up to charge it. It is a good idea to buy a 240V smart charger to connect to your battery when it is at home so you ALWAYS have a full battery.

I have a panel on my van and it is great to be independant with power. I can even run the caravan frige on 12V during the day as we are travelling without worrying about a charging system from the car. My panel is 120W though. Panel prices are going down all the time now. It works so well that I haven't used my generator in over two years.

[Bigrig]

It really depends on two things: usage and sunlight. If you start out with a fully charged 100 AH battery and you only use it spareingly, then it should last you for days without any worry. The 20W panel will assist in prolonging the charge in the battery - but at best you are only getting about 1.5 amps out of it. The main problem with solar is that people put their vans in a shed between trips and start out with a less than full battery. Not only does this stuff the battery - but you are always playing catch up to charge it. It is a good idea to buy a 240V smart charger to connect to your battery when it is at home so you ALWAYS have a full battery.

I have a panel on my van and it is great to be independant with power. I can even run the caravan frige on 12V during the day as we are travelling without worrying about a charging system from the car. My panel is 120W though. Panel prices are going down all the time now. It works so well that I haven't used my generator in over two years.

Hey mate - can you throw up some snaps if you get the chance? I will eventually be getting the fridge, and after seeing tuf42's setup, and hearing about yours, I am thinking this is the go.

[molongmick]

It is a good idea to buy a 240V smart charger to connect to your battery when it is at home so you ALWAYS have a full battery.

I can even run the caravan frige on 12V during the day as we are travelling without worrying about a charging system from the car.

Thanks, the van has a smart charger built in, and yes I charge it before we head off. Our fridge in the van is three way and runs off gas while camping, so no need for a great input of power into the battery. I will use a cable and place the panel in a good sunny spot. You are right, the amperage of the panel is 1.26/1.14 amp.

As I said I only want to ensure that the battery is topped up. I am sure I can get another two or three panels for next to nothing off my mate, which would make it 40 to 60 w.

*edit typed battery instead of panel*

[BillsGU]

Hi BigRig,
Haven't got any photos handy - but if you can imagine two roof bars on top of the van - the solar panel fits between them using two lengths of ally angle. The installation was simple - the only trick is getting the cable through the roof without water getting in. I used a gland nut and sealed everything with GoldSeal. I started off with a portable panel - but it was a pain in the end. Now this one just sits there and does its thing.

I did make sure that my solar charger (from Jaycar) and the wiring could handle double the current. If 120W is not enough I can put a third bar on the roof and put another panel bewteen the centre bar and it. So far 120W seems to be plenty.

[Bigrig]

Hi BigRig,
Haven't got any photos handy - but if you can imagine two roof bars on top of the van - the solar panel fits between them using two lengths of ally angle. The installation was simple - the only trick is getting the cable through the roof without water getting in. I used a gland nut and sealed everything with GoldSeal. I started off with a portable panel - but it was a pain in the end. Now this one just sits there and does its thing.

I did make sure that my solar charger (from Jaycar) and the wiring could handle double the current. If 120W is not enough I can put a third bar on the roof and put another panel bewteen the centre bar and it. So far 120W seems to be plenty.

Champion! Thanks for the response mate.

[the evil twin]

That combination will put about 8 maybe 10 Amp Hours a day back into the Battery on a nice summer day. If you are using lighting only and the pump for camping then that will prob keep the Battery up BUT you will need to park the Van in pretty much full Sun all day... 1/2 a day of Sun (say mid morning to mid arvo) will put in about 5 Amp/Hours as the Panel and Angle of the Sun will be at optimum efficiency.

[Finly Owner]

http://www.batterytraders.com.au/solar-product-cat.asp
try link for all brissie boys and tell Lorna, Tim from Kennards sent you.

[BillsGU]

Hi E.T.

Even with and average of 4 amps per hour on a day of say only 6 hours of sunlight, you are still putting 24 A/H per day back into the battery. Mine is usually a LOT more than that.