Thanks everyone for the feedback!
If i don't catch anything after an hour i give up
Don't I know the feeling!
I should have clarified though, this is trolling along a beautiful Greek island coastline, sipping cool drinks, and relaxing, so quite prepared to suffer in silence for a bit longer!
Now, the problem occurs when you spent more than a few days there, since you are not really operating the main engine for any period of time sufficient to recharge. Add to this a downrigger and the problem is complicated further.
I do take the points though. Probably a Solar panel with a MPPT black box is the way to go.