I disagree on the pay for itself. It will, eventually. It just depends on how much you sunk into the project that will determine how long it'll take to pay back. Even if you have cheap local power, that just means it will take longer to pay back.
For Pete, he's running fairly balanced atm, if I remember correctly. His costs saved vs costs output is about a stale mate. This is partially because he still grid connected and partially because he still doesn't have a large enough system to fully go off grid for his needs.
For me, I have one of the cheapest power in the US @ $0.13/kWh (including taxes and fees). I use about 26kWh/day, which equates to 9.9MWh per year. This costs me about $1300 in power per year. If I built a system that would take me fully off grid, it would probably take 2 - 3 years to fully repay back.
Again, this is my setup and my ROI is fairly short. Others will be different, and Pete's is definitely much longer than time than mine.