It is more or less the shortest day of the year (ie probably least insolation)
and yet I've still not needed mains electricity for lighting in my office
since July, and right at this moment (13:04 GMT) my Internet-facing server
is running off-grid on surplus power from my PV system.
I also charge my mobile phone from this PV system, almost exclusively.
I'd say that this pilot is a success on those terms!
Of course, grid power is cheap, so I'm not "saving money".
But I have taught myself a huge amount about the value of energy which has helped me radically cut my own consumption, and probably be happier for it too, strangely.
And I do have a tiny bit of independence should we have a power cut (for lighting and keeping a mobile phone live for emergencies) though cuts are very rare here in urban London...
Rgds
Damon