[JKCalhoun]

12V has been standard in auto/marine for quite some time. There are plenty of consumer items that already run on 12V.

Power hogs like refrigerators, window-AC units would no doubt still run on 110/220.

But I already have mixed voltage AC in my home: otherwise 110V but purpose-placed 220V for electric stove/oven (in kitchen) and electric clothes dryer (in garage).

In my perfect future only those high-current outlets would remain — the rest of the house would have 12V plugs and lighting.

[throw0101a]

There is more and more 24V in marine systems to deal with higher loads in recent years. Your 28' (8m) day sailor may not need much more than a starter battery, but once you're at 40' (12m) and above things start changing. E-motors in the marine world generally use 48V (AFAICT).

48V is also being looked at in the auto world as well, at least for "low voltage" stuff:

* https://www.automotiveworld.com/articles/48-volt-likely-to-b...

The IEEE's 802.3bu PoDL can handle sending 12, 24, and 48V, and automotive is one of its deployment spaces:†

* https://blog.siemon.com/standards/ieee-std-802-3bu-2016-powe...

* https://en.wikipedia.org/wiki/Power_over_Ethernet#Standards_...

† 10BASE-T1, 100BASE-T1, 2.5GBASE-T1, 5GBASE-T1, and 10GBASE-T1; .3cz task force is working on 25/50/100 Gb/s.