My secondhand van came already fitted with a solar panel on the roof. The habitation battery is, I think, not in the best of condition - the battery is discharging such that every couple of weeks I need to hook the van up to the mains, before it discharges completely, despite the solar panel putting charge in every day. The only draw on the habitation battery is a small digital clock.
On a day like today - cold, overcast & cloudy, van parked between buildings but not in shade - I've typically been getting 0.3A going from the solar panel into the battery, according to the control unit. The panel has no indication of wattage on it, but as it's 650 x 1450mm, looking at websites selling panels I'm guessing it's a 120w unit. Does 0.3A in these conditions sounds about right?
I'm hoping that once the habitation battery is changed, the panel will in winter provide enough input to keep both the habitation and vehicle batteries charged - stop the alarm flattening the vehicle battery. They are linked with a Sterling battery maintainer, but at the moment that's not really doing much as the voltage in the habitation battery drops too low for it to switch on.
On a day like today - cold, overcast & cloudy, van parked between buildings but not in shade - I've typically been getting 0.3A going from the solar panel into the battery, according to the control unit. The panel has no indication of wattage on it, but as it's 650 x 1450mm, looking at websites selling panels I'm guessing it's a 120w unit. Does 0.3A in these conditions sounds about right?
I'm hoping that once the habitation battery is changed, the panel will in winter provide enough input to keep both the habitation and vehicle batteries charged - stop the alarm flattening the vehicle battery. They are linked with a Sterling battery maintainer, but at the moment that's not really doing much as the voltage in the habitation battery drops too low for it to switch on.