What’s the advantage of DC? You presumably still need to step down from high voltage or you end up with expensive thick wiring to avoid resistive losses.
This way DC -> DC fast charging could be a thing, also my DC -> DC oven could pull a lot more Amps and pre-heat very quickly.
Inputs:
- Solar Panels -> Battery Bank
- Grid <-Inverter-> Battery Bank
Outputs:
- Battery Bank -> Washing Machine
- Battery Bank -> Lights
- Battery Bank -> Induction Stove
- Battery Bank -> USC-C to charge devices (my devices could charge so fast!)
A lot of the things you are talking about will require conversion. LEDs will still need conversion from line voltage. Any incandescent lights will need AC conversion. The USB-C adapter will still exist, and there would no effect on charging speeds.
You can get most of the benefit by having DC power cables between the battery, solar panels, and inverter.
Most certainly DC to DC is faster. It is only limited by the local infrastructure. i.e. want to charge faster? own a bigger / better battery bank, with bigger charging cables and a better car.
DC -> DC (with some PWM / battery management) can also be slowed down (or use reduced amps) to best suit the moment. So if versatility is better, then DC to DC is again "better".
Batteries need DC to charge and putting the transformer in the external fast charger means the one in the car itself only needs to be sized for lower power domestic charging.
Resistance is inverse to the cross sectional area of the wire so to compensate you need thicker wire, 10x the diameter (100x the area) for 1/10th the voltage x 10x the current. That’s why the wire that connects to your car battery is so much thicker than the mains wire in your home.
You could have high voltage DC in your home but then you still need the transformer so I’m not sure it really buys you anything.
If you're prefer you can think of it as: each room gets its own Tesla powerwall, and therefore the battery to wall socket resistive losses are negligible.
Latest standards seem to max out at 90W. https://www.analog.com/en/technical-articles/ltpoe-extends-p...
Over the 100M max cable length voltage will drop 25% from 56V input to 48V output. http://poe-world.com/Calculator/
For the same power draw, losses are 4x as high as at 110V, and 16x as high as at 220V. DC/DC power adapters are more efficient at low power (a few watts), so PoE might conceivably be marginal efficiency win for powering a bunch of low power VoIP phones. But as soon as you want to do something like power a laptop or even fast charge a mobile phone, you’re going to be better off plugging it into the mains with a modern AC/DC adapter that can be 95% efficient.
It’s not that AC is better than DC, it’s that higher voltages are far more efficient than lower voltages as soon as you need even moderate amounts of power over moderate distances.
e.g. cordless vacuums / lawn equipment with swappable batteries.
e.g. water proof electric shavers, toothbrushes, blow dryers.
Likely soon induction stoves, air fryers (for instant pre-heat), heat pumps (including the fridge / freezer), blenders, etc. If it can run on USB-C, off the wall cool. If it can't add a battery.
AC arcs self extinguish every 100 or 120 Hz.
Caveat: Unsubstantiated statements follow. There would be some EMF around the wires. While 60 Hz is probably less detrimental, the harmonics (of higher frequencies) are. The effects are subtle and possibly not obvious for healthy people, but can make a difference with autoimmune issues.
Note most of his experiments correspond to radio waves ( WiFi, AM FM etc). But I see no reason to not extend the concept to 50/60Hz and resulting harmonics.