Steve - thanks for starting this thread. It has been five years since the last update on this thread - so there should be a much larger set of solar PV audiophile users by now?
My SunPower system with Enphase micro-inverters was installed two years ago on a detached garage with a metal roof. All of the solar control panels attach to an electric subpanel in the garage. I'm uncertain about the connection to the grid - I have a buried line that runs from the transformer and meter on the utility pole. I assume it connects to the main 200 amp panel in the house, with another buried line connection to the subpanel and solar in the garage. I assume it is all original wiring from when the house was built in 1980. I'm the last house on the power line in a very rural area - not sure it that is good or bad.
I have twenty-eight 410 watt panels, rated at 11.48 kW maximum power and estimated annual generation of 17.5 kW hours. Like Steve, my actual power generation has been about 7% higher than the estimate, probably because of more sunny days than used in the weather model for the estimate. I really like the system monitoring tools that SunPower provides. I am worried about their recent bankruptcy and how that might affect my system monitoring tools and warranty in the future. I wanted the REC Alpha panels but there was a supply problem in 2022, so I ended up with SunPower.
Neither SunPower nor my installer noticed that one panel sometimes stops producing power due to high line voltage, so I need to monitor the system myself for any issues. When I asked SunPower to check on this they said: "the system encounters high voltages ranging from 250-262V from time to time", and the panel with the most sensitive micro-inverter shuts down, which apparently decreases the line voltage enough that the other panels continue to operate. I also asked my utility company to check on this and they said "the only times the voltage gets above 250 is when the solar is producing. Otherwise, the voltage is in a normal range of 246 to 249".
Solar PV in the US is 3x more expensive compared to Australia where installation is a much simpler process. We really need to improve the US permitting and grid connection/infrastructure process to reduce the installation cost.
I'm not using any power conditioning or filters, and this is the next issue I want to investigate in my system. For "critical" listening, I can power down everything in the house except for the router/wifi. I've compared the system on wall power versus battery power using EcoFlow and GrowWatt pure sine wave solar generators and did not notice any difference in the sound quality. Maybe I have really good line power, or maybe my line power and the AC inverters in my solar generators are equally noisy.
Or my amplifiers are not sensitive to pwer noise (Boulder 866, AGD Duets, Pass INT-25, dartZeel 108 with darTZeel preamp running on battery).
Generating clean power seems like such a complicated process, and I'm not really sure where to start. I'm thinking about trying a PS Audio power plant as a first step. Or maybe I should replace my main panel. Or maybe I should just chillax and enjoy the music.