Solar Panels

MacClan

Hi I'm looking for some guidance on solar panels and there usage etc?  I was given a solar panel by a colleague at work.  Originally I was thinking about it being used for trickle battery charging whilst the caravan was in storage etc. The solar panel is
3ft long and is a Maplin TPS-102 12W. It has a single wire finishing in the male connector of a 12v cigarette style plug.  Help suggestions
please?  What would you consider to be the best use for this please? All help gratefully received,  thank you