J. C. Mc Laughlin wrote:
Dear Rob: Of course I know what a three phase system is. In North
America, most high voltage (HV) is distributed using three phase. In a
residential area, a transformer's primary is connected to one of the phases
(with secondary producing what you call a 2-phase, 120VAC - 240VAC system).
At the next house, or group of houses, down the road another transformer is
connected to a different phase - and so on. Because the net power factor of
a residential area is inductive, periodically one will see a platform on a
pole holding three sets of capacitors each connected to a phase.

Like in the UK, we don't have low and medium voltage power distribution
on poles.
All local distribution is underground. Only high voltage is distrubuted
(between cities) on overhead cables.

It is most interesting to learn that in the Netherlands it is common to
deliver three phase to a residence. That is a surprise.

It is common, but not everyone has it. However, it is the normal situation
to distribute 3-phase power to every residence and then connect only a
single phase to a meter, picking another phase at each residence. On
request, the connection can be upgraded to 3-phase by exchanging the
meter and adding two more fuses to the already present 3-fuse box.