Originally posted by @Jacob D Adamczak:
@Frank S. There is no way payback in Chicago is 20 years! Its a 5-7yr payback in Buffalo, a similar climate with less days of sunshine. The only way the payback is that low is if you have a lot of shade or the company is charging wayyy too much.
Like everything, it depends...
It's been a few years since I ran the numbers.
You mentioned Buffalo, the City of Light! Does Niagara Falls helps defer your electric costs?
Do you use electric heat or gas heat? Do you use electric water heaters or natural gas? Do you use electric stove or gas?
I think that area uses electric based appliances because it's cheaper than natural gas.
Your electric bill may be lower than Illinois, we are natural gas based.
How big is the house? How much do you consume? Are there tax breaks available?
Now, a 10Kw is about $25,000 easy without uncle Sam kicking in. Then, you may need a new roof to place them, add another $10K / $12K if you do.
At $25K payback is about 20 years. At $35K, you are doing it to feel good about the planet, which is fine! Then, consider the expected useful life of the equipment, I'm going to eyeball it at 25 / 30 years or so.
As a environmentally friendly engineer, I support green incentives, absolutely. Even without payback, it's worth doing it. If you get a payback, well, there is no choice to make than to be green.
Frank