It mentions that this 9.9 kW system dropped to only 20 kWh per day as winter started. That is rather low. Annual average here in Florida is about 5.5 hrs of nameplate production per day. In most of California, I believe it is at least that if not better. At only 20 kWh per day, that's just over 2 hrs. It seems that's rather low to maintain an annual average of 5+. Are these panels less efficient than conventional ones? Or is the inverter they are using very bad during periods of low output?
Also the price.. $62,000? A convention roof is what? $15,000, so that leaves $47,000 for solar. Even if it is getting 5.5 effective hours per day, that's 19,874 hWh per year, or at $0.15 per kWh ( what I pay down here in Florida ), saves you $2,981 a year. At that rate it will take over 15 years to pay for itself, not counting interest on the initial loan. When you factor in interest, it probably won't ever pay for itself. That's... not very good.