when I was talking to the "solar guys" they said that they do not recommend "going of grid" because of the battery expense (this may not apply to the homemade thing-a-ma-jigs).

They said that when you are producing extra Kw hours (daytime), it makes your meter run backwards. For each Kw you produce in the day, you get to use it at night, or whenever your Solar power can't keep up. So it really is a 1:1 ratio of Kw hour to Kw hour. That way if you need to pull some heavy amps (dryer, microwave..ect) you are still attached to the grid. From what he said is that at the end of the year, if the energy company owes you they will write you a check. Don't get excited, they pay you pennies on the dollar. So don't think you can get rich doing this. Though it has crossed my mind.