Solar Panel Efficiency Calculations
I am going to buy a 13w portable solar panel to trickle charge my 100ampere leisure battery whilst in storage with no 240watt power available. I have established the caravan uses a total of 0.14 amperes for the alarm when switched on, and fridge and radio
(even when switched off). I have no intention of buying a large panel due to cost,fitting etc. On site in the main I will use a hook up.
So are these calculations somewhere near to reality?
A 13watt panel gives maximum of 1.08amperes per hour. Assuming average daylight of 8 hours this would relate to an average of 0.36amperes. Also assuming diminished light levels in winter say to 50% this would give 0.18amperes. On that basis the battery should
replace the discharge caused by the accessories, discounting general loss.