A lot of the sales pitch is in the flavor of "green". How many tons of CO2 you're saving etc. This part of the pitch comes across like Charlie Brown's teacher "Waugh, wa wau, wa-waugh". IMHO the entire green movement is simply an excuse to convince and/or coerce people into changing the way they live, even if it only make sense in the Gaia religion.
We are doing it because it makes financial sense.
We live in the desert and have sunshine a plenty!. Particularly in the summer months when we need more power to run the air conditioning. The panels will also shade a portion of the roof reducing that heat load on the house. The financial calculation does not include that contribution. It makes financial sense because our total cost is about $11K. We expect the system to pay for itself in a decade and save us another $10k over the next 10 years. That's based on the assumption that electric rates stay the same and I just don't see that happening. Thus the pay off will be quicker and ROI larger.
Also, they maintain and monitor the system and the contract includes a performance guarantee where they will pay us if the system does not hit production targets.
The benefit of the system is partially built into the utility rates. Our rates have three tiers. The first 700KWh are at at price X, the next 1300 cost X+ a little, and over 2000 are priced at X+ a little more. So this system removes KWh off the expensive end of that equation.
I searched for complaints against Solar City. The one argument against suggested that it's not a good deal because if you let them finance you, you will pay more than the benefit to you. Could be. But we are paying up front and I don't see that scenario playing out. Also they note you never actually own the equipment. Roger that, but I expect with the rate this technology is evolving, in 20 years what is installed will be old hat and they won't want to take it back.
Future installments will look at different aspects of the decision to pull the trigger. Feel free to post question in the comments.