48v is what most home battery/solar systems run off. Also coincidentally POE, IMO it makes a much more sensible candidate as it is still 'safe' while carrying 4x as much power for a given cable gauge. Consider laptops are 19 or 20v so you would essentially /need/ a minimum of 24v.
reply> I think it's highly unlikely we'll see mass scale retrofits, but if enough momentum builds up, I can see it as a great bonus feature for new builds.
replyI imagine rooftop solar could also source DC for the house directly (or via a battery), before hitting the inverter... ?
The main problem I see is educating consumers. Maybe that starts with a standard for DC outlets and plugs that can't be confused with AC... ?
(Now I'm imagining desktop computers with much simpler power supplies; but you'd presumably have to wire for dozens of amps incoming...)