Which solar panel...?

[apcomark]

H....ineed some advice from u lovely peeps.... am looking for a solar panel that will allow me to become pretty much off grid .... all i really run well on trips in the van is a laptop 17" to watch movies in the evenings ..... just want a panel that will replace the power used by the laptop running....maybe 3-4 hours a night ...

i have a 110 amp leisure battery... run laptop off cigarette attachment... also have inverter for charging camera battery not used very often ....
any of the following anygood....? or what do you recomend ....

20 watt panel.. http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... K:MEWAX:IT

or 30 watt http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... K:MEWAX:IT

or 60 watt http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... K:MEWAX:IT

these are monocrystyalline are they any good i hear there are differing types of photovallatic panels .... and am confused the choices seem endless...just want something to suit my needs on a tight as budget as possible... is there a formula for workin out power consumption.....in laymans terms that is ....?

[R0B]

some handy info here

[Malky132]

Is the leisure battery charged from the engine, or is the solar panel going to be the only power source? If the former, you probably only need a top-up charge anyway, if the latter, I suppose it depends on how heavily you're going to use it.

I've just fitted this solar panel:

http://www.maplin.co.uk/Module.aspx?ModuleNo=115194" onclick="window.open(this.href);return false;

sucker mounted on the inside of my rear window - I swithered about a bigger, more powerful panel, but I decided I would lose too much window and, having a Devon pop-top, this fits the area in front of the water tank and is pretty neat from outside and hardly noticeable from the inside. It trickle charges my secondary leisure battery (under the rock & roll bed) and I run an inverter from it from which I charge/power my laptop or charge my phone/MP3 player or whatever. Every so often (panning out to be 4 to 6 months) I give the battery a boost, but to date I've not had problems with it going flat. But then, I'm only using it to watch the occasional movie.

[apcomark]

cheers for the info

yeah i have a relay that charges leisure battery from the alternator..... just need a smallish panel for topping up .... still wondering what size to go for looks like about 30w might be sufficient....?

[jamesc76]

I've got 48w panel on my roof works great any smaller and not really gonna put much charge into the battery, thos 4.8 ones are only any good for a van parked up for long periods with no drain on the battery over a weekend it wont even put a gnats chuff into the battery!


Edited for Ian

[Ian Hulley]

it wont even put a natts chuff into the battery!

Gnat's spelled with a 'G'

Ian

[The Octave Doctor]

I have a 60W solar panel on my hardtop roof wired thro charge controller to Elecsol 100aH leisure battery. Also a split charger system for when on the move. I run a Waeco compressor fridge, few LED lights and phone charging. I have had it for over a year and the panel is good enough with leisure battery to run fridge for at least a week - its never failed me yet. I do only go out and about in summer when you get max benefit of our long sunny days.. My only advice is to get as large a panel as possible - agree the smaller ones really only good to top up battery when laid up over winter. Oh - and also if you do attach it to the hardtop make sure you leave a small gap between the panel and the roof.

[kentishvanman]

Hi,
Some useful information on www.midsummerenergy.co.uk
Different types of panels, size calculator etc
Don

[The Octave Doctor]

Hi,
Some useful information on www.midsummerenergy.co.uk
Different types of panels, size calculator etc
Don

That is a great site..I like the look of those flexible panels

[kentishvanman]

..I like the look of those flexible panels

So do I. Just needs me to work out what size I need. Planning to stick it on the front of the hi top.
Don

[BARNYBG]

I know this dates back to June,but for any new members looking through..
I would go for as big as you can afford or fit,with a relay/charger thingy,also make sure you get another battery the same as you have,or buy two new ones,and wire them in tandum to each other,this is as the OP has asked ,for going off -grid ,for any length of time.
I have a 100 w solar panel,glued onto the roof via two alloy strips which bolt to the solar panel aluminium edges,on flat on the roof gives a better sun trap and is out of the way from scrotes etc,wire runs from there to the relay/charger which automatically charges or not,depending on batteries,so not to overcharge them,the wire goes from there to the leasure/ lorry battery/ies,these are independant of the starter battery and alternator,i have had this set up fitted to camper for almost a year now,with no problems,a little expensive maybe at just under £400 for whole kit(inc special glue) but to be free of electric etc is worth it.Try to use 12v with as much equipment as possible,but otherwise use an inverter big enough for your needs but not too big,as these use power theirselves !
I can have a tele,laptop,how water or shower with mine,and have been away up to 3 weeks so far without problems.
If you sell the van,either point out how great it is and charge the buyer the extra cost or take off,and use on the next camper etc.