In my case, because of the incentive we're under, all solar produced power goes to the grid. (We have two meters, one for incoming power being used and one for outgoing power we've generated).
Before solar I tried Red Wine (Vinnie's first company) battery powered integrated amp (7 wpc) and DAC. The amp did a remarkable job at driving my loudspeakers but ultimately was underpowered. The DAC could run off battery or AC. In our then new house (with improvements made for audio) it made no difference.
IMO the advantages of power conditioners are location and time dependent. Older appliances in the home, how power might be shared with the same transformer, older factories that share the same substation, utility distribution systems, even the substation itself can all generate power aberrations (the correct term for dirty power). My previous house was 50 years old, the wiring had been amateurishly redone a number of times, and had older appliances yet a power conditioner had almost no effect. My current place was built in 2005, has it's own transformer, all 20 amp/12 gauge or better circuits/wiring, all then new appliances, and as mentioned a couple of improvement for the audio system. So have no complaints about power.