Because of the persuasive opinions in this thread (thank you!), I decided to purchase the system instead of a lease or PPA! There were three big factors that changed my mind:
First, the system is ours to do with whatever we want; we'll be able to expand it, move it to a different house, whatever, and that will make selling our home much easier (no contingencies on whether the buyers can assume the existing solar agreement, the panels will simply be a part of the sale).
Second, our total commitment (after incentives) will be in the range of $15,000 (without financing). If we did a lease or PPA, our total commitment was in the range of $27,000. So by buying, we significantly reduced the overall commitment, making it a far less intimidating decision. (I know we'll need to replace our inverter in ~10 years, but I figure by then they'll be smaller and less expensive... and maybe even more efficient.)
Third, the local installation company (that was offering the Sun Power lease) also sells SolarWorld panels. They gave us an excellent price, and I'm happy to be buying high-quality, monocrystalline panels made in America -
and supporting a small, local business at the same time. I anticipate SolarWorld will be around a long time and will be there to honor any warranty issues, and the installer has a good track record as well (they installed my parents' solar pool panels about 15 years ago).
On Monday they're going to install the roof mounting posts, and then we're going to put
GacoRoof silicone sealant on the entire roof. Then they'll be back to install the panels later this month. Hooray!
Thanks again for your info and help - I'm truly grateful.
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Assuming the lease terms in NY are similar to what I saw in CA, the pricing is significantly better than what I was offered here in Santa Monica (NY State incentives?). Solar City was offering me 16.4 cents/kWh on the lease, which would have meant $113/month (plus an annual 2.9% escalation) for a 5.25kW system. Looks like this is a system twice the size for $137/month. (Your estimated production isn't doubled, though -- My 5.25kW system was estimated to produce ~8,000kWh/year. Yay Southern California!) And yes, it was no out-of-pocket; my first bill was just going to be due after they energized the system.
Do be careful of the annual escalators. Plug that in to my spreadsheet and you'll easily be able to tell how much that will be after 20 years.
http://andrewwilder.com/solar_cost_calculator.xls
Also, once you do the credit check they'll give you the full lease agreement to sign. Read it VERY VERY carefully!! There's a lot of language in there that favors Solar City, especially with regards to the power performance guarantee and what your options are when you sell your house.
Hope that helps!