I have a residential solar installation, and the inverter makes some noise when the relays are switching between import and export. I'm not complaining - although it was indeed surprising

Yeah they claimed the associated hardware for it was noisy. I don’t want to link to the actual comments because that’s kind of mean spirited, I’m just pointing out that I’ve heard people complain about the noise from solar and it’s pretty wild to me. I’ve been in close proximity to pretty large arrays and in plenty of homes with them on rooftops. You don’t notice them at all. They also don’t make the air around them unbreathable