waltraud wrote:I have used a very small maplin 13w briefcase panel for years. I know this id not much with my 85a leisure battery but ALL my interior lights are led, sterio on occssionally, small dvd player sometimes used evenings. Fridge on gas. Works for several days but then I suppose not much draw. Just put a 50w on the roof cos I fancied playing.
The 13 Watt panel is fine for topping up (e.g. when not in use), but based on some calculations:-
13 Watts x 6 hours of good bright sunlight per day = 78 Watt hours
78 Watt hours/12 volts = 6.5 Ah per day
85Ah/6.5 Ah = 13 days to charge your leisure battery from flat assuming 100% efficiency (which it never will be)
So in a cloudless heatwave, you might be lucky to charge it in just over a couple of weeks from flat, so it really does depend on how much you are drawing from it
I have heard lots of willy waving, folks saying their panel still produces X amps even on a cloudy day, but I have yet to see any proof.
I'm telling you the truth, the same truth T'onion and others have told you .... I can't give you ampages to 12 decimal places 
and if you choose not to believe us then that's fine BUT ask yourself this ... What do I have to gain by lying to you and the other nice members here ?
), sometimes a 19" TV, sometimes a laptop, etc etc, so even with my good as new 110Ah battery, this does require a fair amount of amps from the panel to put it back to 100%. I find that on an overcast day, this often doesn't work.
