True, but its too easy to get lost in financial modeling. There were two high order bits in my decision, first was that the money was spent either way; Either I would be paying PG&E month to month, or I'd be paying off the system. And there was a good shot that the panels would generate as much or more energy for that investment. The second was that I felt it was the right thing to do, not a lot of people were in a position at the time to pay those sorts of costs and I really believe that finding better ways to power the world was a noble cause, by investing in a solar system, even if it was a 'bad' investment, it was jumpstarting the market for solar. That helped with the chicken/egg problem of people investing in new solar tech to meet a market that was (by the action of early adopters) clearly emerging.

So every time I find myself having this discussion in a group, there are folks who want to argue the financial model to "show" something (generally negative) about solar power. Either it's not a good investment, or it's just coal power used to make the stuff that now is generating not even as much power was was used to manufacture it, or it's causing more pollution by forcing utilities to turn plants on and off, etc etc.

I was fortunate that I could finance it without risking things like my kid's college fund, I live in an area where there is a lot of sun and mild weather so my house's "demand" is quite manageable, and as an engineer I get to live my belief that we can engineer solutions to the worlds problems like energy interdependence and climate change.

I am grateful that today, the systems costs have gotten so low that it's possible for more people to make that choice.