The systems you see on the big houses took advantage of a tax incentive to reduce our need for energy.
http://photos.uc.wisc.edu/photos/716...jpg?1286779881
When the power fails on the grid most of these homes go dark. A few spent the extra money and loaded up on a
bank of batteries.
http://powerwaterheat.com/images/ful...o_fullsize.jpg
Now lets be honest - batteries in a basement is not a wise idea with all the gases that vent.
These systems were behind the wall at Circuit City to keep the lights on in the dungeon, of the store I worked at.
http://diysufficient.com/wp-content/...tery-bank2.jpg
So the most important thing to think about is - what do you want to power when the power fails? and for how long? How many days of light vs bad weather do you have? Solar may not be the best thing if you live in Buffalo NY for example. You have to store enough energy to make it thru 5+ days of bad weather. You have to be able to knock the snow off the panels. It's never about fussing around with a toy and trying to make it work for your needs. Once you figure that out ... the rest is easy. And no I am not an expert. I have four years of education of electronics. I have worked with real Hi watt panels, built battery banks that filled a garage, and solar power heated a 4x25 foot above ground pool, well into late fall and early spring.
I still have that 4x20 water heater still in the basement.