Solar panel charger

[Davey-T]

Been having problems with condensation on the mount / scopes overnight, when I take the cover off in the morning it's dripping wet at times even when not having been used the night before so I've got a 12 volt pet heater pad and a 22ah golf cart battery and thought I'd get a small solar panel to keep it charged rather than have to make sure I kept it charged up and possibly have to buy another battery to swop them round.

So after all that preamble who knows how big a solar panel I need to keep a 22ah battery topped up bearing in mind this is the UK we're talking about.

I have a small cheap one £10 from Maplin that proved useless for keeping my camper van battery topped up.

Dave

[richyrich_one]

Check these out...

http://www.sunstore.co.uk/shop/

[Davey-T]

Doesn't seem to be any difference in the winter output 1ah between 10 / 20 / 30 watt panels ?

Dave

[RayD]

Depends if you are using a charge controller Dave.  If not then you are limited by the maximum charge rate of your battery, which is typically 10% of the rating (2.2A).  This means you would need to get a 30W panel.  If using a charge controller you can use a bigger panel but the controller will limit the output.  Whilst this won't supply any more power as this still shouldn't exceed 2.2A, the bigger panel makes charging more efficient in cloudier conditions.  You can use smaller, it just means it will take longer to charge the battery and, if not fully charging, possibly damaging it.

These are my panels in Spain (6Kw off grid system), you can rent some space from me if you like 

 

[Davey-T]

 

 

1 hour ago, RayD said:

Depends if you are using a charge controller Dave.  If not then you are limited by the maximum charge rate of your battery, which is typically 10% of the rating (2.2A).  This means you would need to get a 30W panel.  If using a charge controller you can use a bigger panel but the controller will limit the output.  Whilst this won't supply any more power as this still shouldn't exceed 2.2A, the bigger panel makes charging more efficient in cloudier conditions.  You can use smaller, it just means it will take longer to charge the battery and, if not fully charging, possibly damaging it.

These are my panels in Spain (6Kw off grid system), you can rent some space from me if you like 

 

Thanks Ray, I can get a 30W that comes with a controller so that should do, be portable enough to take camping

Dave

[RayD]

13 minutes ago, Davey-T said:

Thanks Ray, I can get a 30W that comes with a controller so that should do, be portable enough to take camping

Dave

That'll work perfectly Dave