for comparison, I pay a flat rate od Au $0.23 /kWh (US$0.18) and use an average of 12.5 kWh per day . Grid service connection fee is Au$0.76 per day. My annual bill is currently approx Au$1700, but this month all kWh rates have been increased by ~20%...so next year i would expect to be paying Au$2000 + unless i do something !!
We dont get a parity deal on power fed back to the grid, but the rates have also increased for next year to Au$0.10 - 0.15 kWh,...so the payback figures do work quite well i think.
those system prices are fully installed ( standard on roof set up), by certified companies , with 10 yr warranty.
Infact i was just quoted Au$3400 for a 6.5kWh system !
i figure with 6.5 kW i can easily cover my daytime usage and likely feed 25+ kW back to the grid which would effectively pay for the evening /night/morning usage.
I am seeing a < 2yr cost recovery, and as you say, an ongoing earner !
Two minor problems though..
roofspace....probably less than enough for 3kW even ! ....without some creative/expensive/ugly framework !
Tree shade..on that part of the roof that is useable, its partially shaded for 30% fo sunlight hours ( morning and evening) ..so the efficiency would be way down on even that 3 kW system !
..Not my trees either,. public parks.
..and no space for ground/pole mount without similar issues...this is a small city lot.
So i either have to start looking for a more suitable property
..or rethink somehow. ???