I don't feel like too much research atm, but I will just say that the cost to the utilities of rooftop solar is controversial. It saves them money as well. The bulk of solar energy comes during the highest demand periods where it is the most difficult (expensive) for the utilities to supply power.
Obviously at some point, the loss of revenue from the sale of energy to solar customers will be more than any benefits.
If the market/technology/prices ever get to the point where lots of people are going off grid, that's going to make things even harder for the utilities.
I've just skimmed this atm, but this is a paper on the cost and benefit to utilities of customers going solar. I read something like this a few years ago and it was pretty clear that solar was benefiting the utilities. Otoh, recently, it seems like Hawaii may have had an issue with too many customers not buying power from the utilities. I'm sure Florida is a long way from that being an issue. Florida is 20th in terms of solar per capita atm.
http://www.environmentamerica.org/si...ards_print.pdf