Is a new electrical ecosystem needed and what could it offer?

Actually, I wouldn't disagree with either @mapj1 or @Simon_Barker's points - the physics of voltage drop are unarguable.  There is no doubt that higher voltages for distribution make sense - not least because better insulation is cheaper than more copper - this may turn out to be the only way we can distribute enough power to charge all the electric vehicles we're going to have.  For a given insulation level, switching from AC to DC gives a 41% power advantage straight away.


What HAS changed is the ease with which voltage can be changed at point-of-load - and DC more easily than AC, so supply voltage stabilization is much less critical than it was.  Buck converters are amazingly small, cheap and efficient - at least for applications that don't require galvanic isolation.  


The other thing that has changed is a growing recognition that the very significant proportion of the 900 million or so world population currently without any form of electricity and who are likely always to be beyond reach of the grid, and the 500 million or so whose electricity is more often off than on, cannot afford self-contained grid-standard solutions.  If the affluent parts of the world take 48VDC seriously, this will help drive the economies of scale for a solution that is more versatile than 12VDC, and more affordable than 230VAC.


Cooking with 48VDC is not a serious option in the Developed World.  However, for the half of the world population that currently cooks with solid fuel, it is good enough to drive a green revolution.


Arcing is certainly an acknowledged concern for LVDC - though arc detection evidently still has some issues.  Some very imaginative ways are emerging for power semiconductors to break the current flow, both in switches and connectors.  This will be very important at higher voltages and currents.


The bottom line in my view is that our capabilities with solid state electronics and the complexities of what we need electricity to do for us justify a re-visiting of the "Battle of the Currents", and a very serious reconsideration of Low Voltage Direct Current as an attractive electrical ecosystem.  48VDC is but one possible point on that journey, and there will need to be others.

Actually, I wouldn't disagree with either @mapj1 or @Simon_Barker's points - the physics of voltage drop are unarguable.  There is no doubt that higher voltages for distribution make sense - not least because better insulation is cheaper than more copper - this may turn out to be the only way we can distribute enough power to charge all the electric vehicles we're going to have.  For a given insulation level, switching from AC to DC gives a 41% power advantage straight away.


What HAS changed is the ease with which voltage can be changed at point-of-load - and DC more easily than AC, so supply voltage stabilization is much less critical than it was.  Buck converters are amazingly small, cheap and efficient - at least for applications that don't require galvanic isolation.  


The other thing that has changed is a growing recognition that the very significant proportion of the 900 million or so world population currently without any form of electricity and who are likely always to be beyond reach of the grid, and the 500 million or so whose electricity is more often off than on, cannot afford self-contained grid-standard solutions.  If the affluent parts of the world take 48VDC seriously, this will help drive the economies of scale for a solution that is more versatile than 12VDC, and more affordable than 230VAC.


Cooking with 48VDC is not a serious option in the Developed World.  However, for the half of the world population that currently cooks with solid fuel, it is good enough to drive a green revolution.


Arcing is certainly an acknowledged concern for LVDC - though arc detection evidently still has some issues.  Some very imaginative ways are emerging for power semiconductors to break the current flow, both in switches and connectors.  This will be very important at higher voltages and currents.


The bottom line in my view is that our capabilities with solid state electronics and the complexities of what we need electricity to do for us justify a re-visiting of the "Battle of the Currents", and a very serious reconsideration of Low Voltage Direct Current as an attractive electrical ecosystem.  48VDC is but one possible point on that journey, and there will need to be others.