solar battery charger

[longreach]

:eek2:just need some advice on a solar battery charger.
I own a 1994 defender,I am running a waeco fridge 40,and one led fluoro camping light,(I have duel fuel lanterns)thats all the power I,ll be using,when I,am camping.......what I would like to now is,what size solar battery charger would need ,20watt,40watt, or80watt ???? I dont want to over charge the battery,(I dont have two batteries)...any advice.......regards keith

[waynep]

hi ..this has been discussed a fair bit on this forum.. .try searching the posts.....

However in general I think you'll find the advice would be to get the highest rated output solar panels you can afford and easily transport/handle. You won't overcharge your batteries if you use them with a regulator.

[weeds]

However in general I think you'll find the advice would be to get the highest rated output solar panels you can afford and easily transport/handle. You won't overcharge your batteries if you use them with a regulator.

yep that pretty much covers it, the biggest your can afford

i have one fitted '65w' as a wind break on my defender, you would need at least 65w as a minimum so you would be looking at $600 +

running one battery with a fridge is risky for extended stop overs, overnight you can get away with

i would first fit an aux battery cause the last thing you need when you want to leave first up in the morning is your battery is too low to start the car, you would than have to wait X amount of time for the solar panel to charge your battery and if you are in a real rush you will need to turn your fridge off to speed this process up

if you decide to only run one battery you might want to fit a low voltage cut out so that you alway have enough power to start your car

one solar panel covered in dust
https://www.aulro.com/afvb/images/imported/2007/09/447.jpg

[Bushwanderer]

yep that pretty much covers it, the biggest your can afford

i have one fitted '65w' as a wind break on my defender, you would need at least 65w as a minimum so you would be looking at $600 +

running one battery with a fridge is risky for extended stop overs, overnight you can get away with

i would first fit an aux battery cause the last thing you need when you want to leave first up in the morning is your battery is too low to start the car, you would than have to wait X amount of time for the solar panel to charge your battery and if you are in a real rush you will need to turn your fridge off to speed this process up

if you decide to only run one battery you might want to fit a low voltage cut out so that you alway have enough power to start your car

one solar panel covered in dust
https://www.aulro.com/afvb/images/imported/2007/09/447.jpg


Hi Weeds,
Do you drop the panel while travelling?

[jik22]

i have one fitted '65w' as a wind break on my defender, you would need at least 65w as a minimum so you would be looking at $600 +


Do solar panels stand up to being bounced around like that then?

[weeds]

Bushwander - the panel sits in that position all the time and its fixed to the top rail of the roof rack. I have two latches so if I need to pivot it up early or late in the day to catch that last bit of sun I can however I haven't really popped it up mainly cause I normally forget and drive off like I did at birdsville with a footy propping it up

Jik22 - my solar panel has been sitting up there for two years without a problem, its been to lawn hill NP and across the simpson. A mate of mine has a BP 80W on his cruise much the same as mine with no issues

[jik22]

Jik22 - my solar panel has been sitting up there for two years without a problem, its been to lawn hill NP and across the simpson. A mate of mine has a BP 80W on his cruise much the same as mine with no issues

Good to know - I thought this would be an ideal mounting position, using a yet to be purchased light bar at the front running back to the roof tent at the rear - but was too scared to go buy a $700 panel and do that to it. :)

[BradM]

What a great idea especially if you are towing a van behind as well.

[Bushwanderer]

Bushwander - the panel sits in that position all the time and its fixed to the top rail of the roof rack. I have two latches so if I need to pivot it up early or late in the day to catch that last bit of sun I can however I haven't really popped it up mainly cause I normally forget and drive off like I did at birdsville with a footy propping it up

Jik22 - my solar panel has been sitting up there for two years without a problem, its been to lawn hill NP and across the simpson. A mate of mine has a BP 80W on his cruise much the same as mine with no issues

Interesting!

I don't have solar panels myself, but a mate has some and when travelling, he drops the panels down and shields them with plywood.

[Dinty]

G'day All, I have 75W solar panel mounted similar to Weeds, it has been mounted like that for the past 16 years with no issues (maybe I've been lucky( cheers Dennis:wasntme:

[weeds]

was camping on the weekend and thought i would take a pic of the solat panel up catching the early morning rays

https://www.aulro.com/afvb/images/imported/2009/08/1272.jpg

[googe]

I wouldnt think a panel would be needed running a 40lt its not a big fridge i run a trogan in my hilux 2x4 for camping with a 80ltr weco u dont need to turn wecos up to high they run better on 2 or 3 lights.
Greg

[longreach]

kelvin,what did that setup cost you ??looks the part:eek:

[weeds]

sorry longreach

i got my solar panel for nicks, i got two secondhand/damaged stock

i'm not sure of the costs now as it was a few years ago

Solar Panel - i got mine for nicks, i think a solar panel around the 80W mark would be around $800

Regulator - there are two type of regulators, a small one that sit in the junction box on the solar panel (i should have got this one) or a bigger external one that i have mounted in my console about $70 i think ( i brought it because it had flashing led's indicating what mod of charging it was in) + plus you need the diode thats stops the battery from discharging at night which was under $10 i think. the best part about the first regulator is if i ever decide to remove the panel from the defender it would have a reg already fitted instead of having to buy another one, i have only looked at the led's a handfull of time in the first month. you can get more advance regulator that record amps in and amps out but all these things use power and are soon forgotten about

Cable - probably spent $10-$20 dollars

Board Rack - i think that cost me around $160, i bit of a shock but i only fitted all this just before heading out to the simpson desert, would liked to have had time to shop around

you would probably need to allow around $1000

[weeds]

just looking at the pic and the solar panel brother is in the back ground chaging the batteries in the caravan

[longreach]

:cool: thanks kelvin,for that information........just trying to work out how to charge my batterys,when I go away over xmas:banana::banana:

[streaky]

What about the anomorphic type solar panel chargers? I picked up a few 13 watt ones recently. They are designed as solar battery chargers and are much much cheaper.

13 watts translates to 1 amp but thats okay for trickle charging a battery system or topping up the batteries when you are stationary.
I also hear that they work well in reduced lighting conditions too.

I've not tried mine yet, but I bought two types. One is a fold up portable type like a breif case. The other is a perminant flat type for hard mounting.
Cost was 55 UK quid each and the regulator was 11 quid. They have the built in diode to stop drainage etc.

Thoughts?

[JDNSW]

What about the anomorphic type solar panel chargers? I picked up a few 13 watt ones recently. They are designed as solar battery chargers and are much much cheaper.

13 watts translates to 1 amp but thats okay for trickle charging a battery system or topping up the batteries when you are stationary.
I also hear that they work well in reduced lighting conditions too.

I've not tried mine yet, but I bought two types. One is a fold up portable type like a breif case. The other is a perminant flat type for hard mounting.
Cost was 55 UK quid each and the regulator was 11 quid. They have the built in diode to stop drainage etc.

Thoughts?

One point you want to watch is that while the power is quoted at 13w this will only be achieved at one specified battery voltage (and "standard" amount of sunlight). At any other voltage the power output will be less, and in most cases the actual charge rate will be a lot less than expected by dividing the rated power by the nominal voltage. For example, with panels mounted on a tracker, I typically get an actual power output of around 45w from panels rated at 80w. Although, depending on battery voltage, the current should be between about 5.7A and 6.6A from the rated power, the current is rarely above 3.5A.

Inspection of the curves for the panels shows the rated power for these particular panels is only achieved at 18v - which should never be reached in normal operation. So why are they designed to give this high a voltage? So that they give a usable charge in less than ideal sunlight levels. But the point is, don't expect to get the rated power in real life.

On the other hand, I have heard of cases where panels have given over 50% above the rated power (with disastrous results for the regulator), but this requires high altitude to give a combination of high UV and low temperature (output decreases as the panel heats up with increasing current) plus snow to give a lot of reflected light. In your locality, you should be aware that high temperatures will reduce the output compared to "standard" conditions.

John

[Jezzaol]

Do solar panels stand up to being bounced around like that then?

I have a 80w Solar pannel fitted to my roof permantly and it maintains a 50lt Waeco Running continuisly, never stops only drive about 1hr every day.
I have done comp work, knocked it on trees, in fact don't look after it at all ! really are strong !

[streaky]

In your locality, you should be aware that high temperatures will reduce the output compared to "standard" conditions.

John

Many thanks for that explanation John. You've obviously done more homework on the subject than me.
Another quick tug at the grey stuff whilst I have your attention........

With regards to temperature abuse. What's considered too much exposure to bright sunshine for the anomorphic panels? A few hours or the entire day? a few days consequetive?
I only want to use them for trickle charging whilst I'm parked up or camping. The main power drain is my 40lt Engal. I know the panels won't have enough output to totally charge my Optima battery but I was hoping it would just help top it up a bit.

Thoughts?

Thanks again.

Regards.

S.

[handy]

I have used the Uni-Solar brand panels, because of a few benefits they have over the competition, or at least had a couple of years ago:

They are advertised as bullet proof, (light gauge I'm sure) but it does bode well if you are caught in a hale storm.

Unlike all of their competition, as the temperature rises they work better.

If they are partly shaded, only slightly more than the shaded area of the panel stops working.

The 64 watter is equivalent in both size & output to their oppositions 80 watt panels.

Uni-Solar cost a little more, but personally I wouldn't use anything else.