So I had the nice sales guy from 'Solar City' - Elon Musk's home photovoltaic rollup - come by and pitch me on taking my house solar. I'm interested, and had the feeling that it was close to actually making sense.
Here are the rough numbers:
For a 3KW installation (about 275 sf of cells), the total cost to me would be approximately $18K. My electric utility uses tiered pricing, we're typically just nosing into the highest tier, with power use of about 800KwH/month (we need to look at that...). 3KW would get me comfortably into the lowest tier and would do things like run the fridge and some lights if we had an outage (which we've never had).
So here's how I'm seeing the economics.
We'd shed about $80/month from our bill. So assume a cost of funds of 9% and am amortization period of 15 years, and we can support about $8,800. Add to that a $2K federal tax credit (the state credits are already discounted into the price) and we're at, call it $11K.
So there's a $7K 'feel good' cost.
But out of that, we can offset two more numbers - increase in electricity prices over the life of the system, and an increase in the value of the house (per the salesman, underwriters will move the electricity monthly savings into capitalized value).
It's interesting - if the number was smaller, I'd certainly do it. If it was bigger, I wouldn't. I'm right on the cusp.
Meanwhile, we'll get a detailed proposal next week.
I'll also get a proposal on solar DHW, which certainly has better economics. But hey, we have a big roof...