I'm a new Citizenre "ecopreneur" in California, and I can't pretend to know all the details, only that I'm working my butt off to educate myself on the issues. I do know that I've waited for 30 years for PV power to become affordable, but it hasn't seemed to be headed that way so far.
One detail that does occur to me is that we are given a figure of 2.1% as an average annual cost increase for electricity from the utility companies. And, that 2.1% annual increase assumes that the cost of coal and petroleum will only increase at the same levels they have historically, which is by no means certain.
Obviously, that can change, but given that figure, a homeowner investing only a $500 security deposit and then paying the same electric rate for the next 25 years could conceivably invest that 2.1% amount on their own and put the interest in their own pocket, rather than allowing it to accrue to the local utility company.
Conversely, a homeowner who takes out a $20,000 loan to purchase a solar PV system and pays it back at 5% over the term of a 30-year mortgage is going to be paying a huge amount of interest to do so, in addition to being responsible for maintenance and repair of the system.
In other words, they would end up paying almost twice the original cost of the system, and they would have to become far more technically sophisticated than the usual person in order to keep repair costs down. And they'd still have to pay for replacement equipment when necessary.
Contrast that with locking in your electricity rate for the next 25 years, NOT financing that equipment cost, risking only $500, and having the option of investing that 2.1% increase for yourself, and this seems like an idea that's worth approaching.
Again, I'm not an expert, but I'm intrigued enough with the possibilities to take a chance on it.