Flexible Solar Panels

I have a 32W flexible solar panel, had it for about 8 years and its exclusively used on my sailboat on salt water.
No problems whatsoever so far, still works well.
You can roll it up (about 300mm diameter), walk on it (smooth soles only).
Mine is a 12V panel, You did not say how your 4x6V batteries are connected.

Sharon,
Why are you looking at flexible panels ??

The 40Lt Engle up there in the heat, the inverter and various other things you nominate will probably use ~2ah so that is what you need to replace.

You need to replace more current than one or two flexible panels can supply, however you will get enough power from one large quality Monocrystalline panel, which can be on an extension lead or attached to the roof.

Maîneÿ . . .

Knowing the capacity of the battery bank, the rate of charging you can achieve from whatever source, and knowing your (estimated) power consumption are pretty important bits to have an awareness of - plus knowing how long you will only be charging via solar - i.e. how many days you expect ot or want to be static camping before driving off and charging the battery bank from the vehicle. Also, the available budget is really important.
I would suggest that you probably need to have capability to charge at 5 or more Amps per hour via solar. Remember that you use power at night when you can't charge via solar and also when you are charging from panels you are still using power so you need to pump in more than you use to make up for the previous night use and the daytime power use.
fridge / laptop / invertor / shower / lights - possibly at a guess ??? 4 to 5 amps per hour when bits are running around the same time (fridge would be 1A to 2A); so would consider at very least 80W of solar panel(s) - with controller (MPPT ones are a little better than the older PWN technology) - but would encourage you to look at 100W, or 120W, or even 150W of panels. Without knowing your power usage per day it is difficult to narrow it down but....as indicated you probably need 80W at a bare bones minimum.
If it was me, I would get the biggest bang for the available $$ dollars - buy the most W of panels that you can afford and allow for increase in panels later on when more $$ become available.
Storage is always a big consideration - and this could determine whether you go for a flexible one; or folding briefcase style multiple panels.
Link below shows 80W (produces 5.2A) and 125W (produces 7.8A) flexible panels that fold up quite neatly but are on the costly side - and include controller. Must also remember that you don't always produce the max or rated Amps.
Site Link
There are now some relatively 'cheap' solar panels out there along with the 'name' brand ones (which you will pay more for). Link is for a mob who do some fairly cheap ones.
Site Link
Also there is Steve at Mandrake's Solar who has a member in ExplorOz Site Link
who also has some good prices - I've purchased from Steve.
http://www.solarsteve1950.com/panels.html

I have 200W of panels (4 x 50W BP panels) which can produce in actuality around 10.5A to 11.A on good solar charging days - and I have way more power usage that you would have - and the solar panel setup still does not quite keep up with my power usage so the genset comes out every so often. I link my panels with some wire strop and padlock to a relatively immovable object - i.e. a-frame.
Hope the above helps a little bit.

Graham

Hi Sharon,

I have bi-fold panels (80 watts in total capacity) that I just prop on the ground.
It is secured by a multi-strand stainless cable which also passes through the portable battery box and fridge, then secured to the camper chassis by a padlock.
This will deter the "opportunist thief" at the least.
The advantage of this arrangement is that you can easily follow the sun as it tracks across the sky. You can't always place your camper in the best position to get the most sunlight.

Bill.

We choose a more efficent option for flexible solar panels , because those type have a low output per unit area.

THis is to use a normal panel which comes without the frame work and is just the cells on an aluminium plate ,covered with plastic membrane, this gives it enough flexibility so that it can be glued to roof of car etc and becomes almost invisible.

E.G. If you look at another current post 78368 , the car has a 60w panel on roof above drivers window , but you can't see it.

Advertized on ebay and built to size - think my 60w was around $300.

Sharon,

As already suggested, you need to get an idea of the amount of electricity you need to meet your daily requirements. Suggest have a look at our blog Electricity for Camping where this, and lots of other stuff, is discussed.

From what you've said, I think you may be consuming 50 or more amphours per day. To replace that with solar panels will call for 150 to 200 watts of solar capacity (and of course, reliable sunlight!) It may be possible to trim your requirements down a bit - try to avoid an inverter by running everything (including the laptop) off 12V.

If my guess of 150 -200 watts of solar capacity is about right, you'll need over one square metre of conventional panels, or a much bigger area of flexible panels since they are far less efficient. A big advantage of the conventional panels too is the ability to set them up facing directly at the sun.

Hope that helps

Cheers

John

My biassed suggestion -

2 X 80 watt solar kit with MPPT reg - anchored to the C/T as suggested above by a bike cable lock ( better than nothing . )

"My profile " will be of assistance .

Cheers

Steve

Sharon,
some relevant information re the "power" supplied in good conditions.

Largest "flexible" panel; 143cm x 42cm, 32 Watts = 1.9 Amps = ~3.1 Amp per sq mt

Sharp ND-L3EJE panel; 149cm x 67cm, 123 Watt = 7.2 Amp = ~7.2 Amp per sq mt

As for the opportunist thief, it would be much easier to roll up a flexible panel than it is to carry away a 14 Kilo solid 1.5 mt long panel :)

For comparison purposes, my fridge draws 2.8ah, yours is possibly even less than half of that, the lights I use are about the same as yours, the inverter, if PSW and an efficient model, yes it will ‘loose’ a few % as it powers the laptop and FAN etc, not enough to worry about and IMO is not worth the worry people give it, I often wonder if they just use a low priced elcrappo one if they even have one anyway?

The FAN can’t be powered by anything other than an inverter, because it’s a 240v fan.

I use ~200 Watts of solar power and have never had my battery system showing <12v (50% discharged) so that is the absolute maximum you will need.

The really big thing you need to remember is *BATTERY BANK CAPACITY*

Having 4 x 6v batteries is ok if the batteries are large capacity DC batteries, this is the important part I don’t believe you’ve mentioned, I believe your batteries are wired in series giving 12v and the ah will then be double what’s stated on a battery.
Eg, 4 x 100ah 6v batteries is 200 Amp Hour.

Maîneÿ . . .

old girl

here's a panel that very versatile, it's a concertina type

http://www.eco-camper.com/component/virtuemart/category/42/flexible-solar-panels.html

This is the battery storage system used by Old Girl (QLD)


Image Could Not Be Found

No, I didn't sell it, suppy it or install it but I believe credit must be given when due and this storage sytem is good

Maîneÿ . . .