It was somewhere outside Barstow when Eradicate Sampson
Post-war copper shortage, together with a housing shortage owing to
wartime bombing and rapid post-war breeding. Everyone wanted houses,
with electrics, and with reduced amounts of copper to wire them.
Some countries, including America, switched to aluminium wire.
Aluminium was cheap at the time, owing to huge numbers of scrap
aircraft. Britain OTOH, just invented the Land Rover as a way of
making exportable vehicles that used aluminium instead of steel.
The British solution to house wiring was the "ring" system. The
previous "radial" system, as still used in most countries, places a
small number of sockets onto separate circuits and fuses each circuit
in a central fusebox. Lots of wire, one to each circuit, lots of
fuses, and poor safety for over-current faults as the multiple sockets
require each circuit to have a relatively large fuse.
Thr ring system still uses copper, but it places all the sockets in a
large area (usually one floor of a house) onto one circuit and one
fusebox fuse. It uses a single loop of medium-heavy cable, which is a
very efficient way of using the scarce material - delivered power for
a given copper area is something like 4-6 times that of the US system,
depending on whether it's a small flat or larger house. Voltage drop
problems are avoided by using a loop, not a radial. The great
advantage of the system comes from its better use of "diversity" -
it's good to provide many socket outlets, but many of them are little
used, and rarely do they carry substantial loads. The radial system
has to wire everything up for the worst case, and do it individually.
The downside is a more complex plug on each appliance, requiring a
fuse. However this also allows fuses to be related to the real
appliance load, not the location. Most of my appliance are fused for
just 1A, but I can safely plug a 3kW welder or compressor into the
same socket, anywhere in the house.
If you look at the fire statistics for UK domestic fires, by far the
biggest problem comes from damage somewhere along a cable (chafing,
rodents, or perished rubber). Relatively speaking we get very little
trouble from connectors or panels.