I've heard of quite a few people successfully doing this. Generally, during those times that their home produces more electricity than it consumes, they merely feed it back into the grid, and their power meter runs backwards. Usually, though, over the billing cycle (i.e. month) they still consume more power than they generate, so in effect they just have a much-lower bill than before.
In a few cases, some people who've done this have managed to consume less power than they generate, and in these instances, the power-company owes them money. The power company usually checks *very* carefully to see that their meter is working correctly, but once satisfied, they do get checks for the going rate for electricity at that time.
Contact
Dr. Alan Zelicoff - he's done massive amounts of research into this. He's even written an
outstanding small book about photovoltaics, saving energy, alternative (and efficient) HVAC systems based on water, etc.