The install includes updating the feed in to 3 phase, who knows a Tesla in the driveway?
For now though, the power company is also the water company. The excess power generated gives us a credit that goes towards the water bill. The in and out tariffs are the same, so at the moment I'm expecting to pay no utility bills for the next 25years.
Or more accurately, I've prepaid our utility bills for the next 25 years.
The install should pay for itself in about 3 years.