hi all, any of you use solar panels to charge leisure battery, i am looking at some 20w ones and also a charge controller with usb connections,also recommendations on leisure batteries please, we have a trailer tent, will be using a cd player (car stereo) and a couple of led lights thanks in advance
Look at the power drain from the car stereo, add the wattage of the lights and divide by 12 to get the current drain.
1A of current used for an hour = 1AH
The capacity of leisure battery to go for depends on your drain, offset against your charging system (i.e. Solar panel). A 20w solar panel is only going to give you just over an amp of charging per hour, so you're going to need a high capacity battery if you want it to last more than a night!
A 200W solar panel will give you about 60AH charge over a day, from memory.
My advice is do the maths to see how much you need then double it. There are so many variables we are just about managing here in Spain with what I thought was an oversized 150w panel.
I'm guessing if you're just using car stereo and USB chargers you'd be ok with a 40w panel, so go for an 80w free standing panel and a Varta LFD90 leisure battery. Oh don't forget the mppt controller, a Votronic duo 165 will serve you well.
Best way to work out the car stereo drain is to look at the fuses (Even if these are worst-case). USB chargers are either 1.2A or 3.1A.
Also, the solar panels quote their maximum output - this will be in bright light at the correct angle and direction - mounting them flat will decrease the efficiency to some extent.
Perhaps a charge controller which will accept two panels? Even if you only buy one to begin with, it means less messing around if you find you need more?
USB chargers are usually about half an amp at the 12v side, even with a tablet plugged in it's no more.
Tom's looking at the 5v output amperage rating which will be more, but is of no consequence here.
Having looked at this in the past i can honestly say it not worth the outlay.
you can get some really good quality led lights nowadays that are rechargeable via 12v or just run on batteries themselves and would easily get 4/5 days out of them. i have a couple ufo style ones for the awning and then a bulb style one for inside. and plenty of solar powered fairy lights!!
with regards to stereo (often a major annoyance on campsites...) i simply take a bluetooth speaker and bounce either radio or music from my phone. easily charged of the car, and i get a good 3 days from a charge (although diminished by a few hours music) perhaps a cheapy mp3 player would work better.
my outlay was about 30£ i have a few options for battery driven lights, you could splash out on something like the kampa sabre.
100 ish quid for a 200w solar panel? 85£ for a deep cycle battery (these batteries only like to be drained halfway, otherwise their lifespan is greatly affected) plus controller bits...
depends exactly one how often and for how long you tend to use it for, i can almost see a justification for extended periods of off-grid camping but certainly not worth it for saving 5-10 on a weekends EHU charge and unlikely to generate enough oomph for more than a week...
I have a leisure battery and charge controller in a plastic crate with a top panel with various sockets and connectors.
We just use it for charging technology and lighting - but with two teenage daughters in the family we have four smartphones, three tablets, two cameras, one GPS, and some bits and pieces using rechargeable AAs.
We use a 60W panel, an Exide 40Ah leisure battery, and a EPSolar LS1024 charge controller (which is a 10A PWM controller that's waterproof) and a remote meter display. This keeps us going in a UK summer, but I don't know how much more drain it would keep up with.
For this size installation it's not worth buying MPPT in my opinion - suppose I used MPPT instead, it would be maybe 30% more efficient, so instead of a 60W panel I might get away with a 45W panel, so that would save me maybe £15 on the panel, while costing me £50 more on the controller.
Gubbins (like USB power supply & battery charger) live in the slot to the left. Solar panel cable plugs in bottom left. Solar controller is obvious - it was dark when I took the photo, so the panel's only showing 1V and 0A.
The toggle switch allows all the outputs to be switched off (in which case the battery is completely isolated), or connected direct to the battery bypassing the solar controller (suppose I wanted to draw more current than the controller output stage will handle).
All our lighting cables end in standard DC barrel plugs which go into the sockets at top right. I have cables for our various battery chargers that go in them too. There are two cigarette-lighter-type sockets (bottom right) for things that you'd normally plug into a similar socket in a car - like the USB power supply we use. The red & black rectangular things are anderson powerpole connectors (the solar connection uses them too) which are excellent high current low voltage connectors but I don't have anything that draws enough current to be worth putting on them.
Bottom centre is a LED that blinks with colour according to battery state - it's faster to glance at that than use the control panel, and it's permanently connected even when the controller is off. In practice it rarely drops off green.
The round red and black things are binding posts / banana sockets - I think the only time I use them is to stick a multimeter on to check voltages. In principle I could put an external battery charger on, but in practice I have the solar panel on a flat roof with the cable through a hole in the wall into a storage cupboard and the whole system is hooked up all winter doing nothing but keeping the battery topped up.
It's all fused with car mini blades.
The panel rests on stand-offs directly on the battery. It's laser-cut acrylic (from razorlab.co.uk).
That's epic! I want one. Even though I have no use for it whatsoever
I once looked at buying some acrylic, it was to put in the motorhome skylight with some computer fans in for a bit of night time cooling. The robbing buggers wanted something like £38 for it. I ended up using plywood and it looks crap
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.
Topic: solar panel and leisure battery
