When dealing with solar panels there are additional efficiency questions that need to be taken into account: maximum power point tracking. You're going to lose lots of efficiency without a MPPT controller.
Docedison:
This whole endeavor is too time consuming for the occaisonal thank you.
I'm sure I'm not the only one watching your responses and not chiming in a "thank you" just to keep the signal to noise ratio high. Not to be a brown noser but I've always given your posts special attention.