"Jaffna Dog" wrote in message
...
On Sunday, 27 July 2014 20:12:35 UTC+1, David Paste wrote:

My question is that if we were to have a brand new electrical system,

common to all areas, what would, or could, it be? Still AC? 300 volts?

Different frequency?





David Paste.

All other things being equal, the only reason for not having widespread
electricity distribution in 2014 would be if the filament lamp had never
been invented, which was the original 'killer app' to make public
electricity supply a viable business. The problem before that was
"sub-dividing the electric light", as in the 19th century, before filament
lamps were invented, only arc lamps were available, and these were only
practical for large outputs, so tended to be used with local generators at
about 100v DC, 70v being needed to maintain an arc in air, the rest for the
regulating resistance to limit the current.

Eventually discharge lamps (mercury, sodium, etc) would be developed, but
not in domestic sizes, these are more efficient on AC supplies, allowing the
use of transformer ballasts, so things would have panned out at 440v 50Hz
three-phase, for induction motors in industry, stepping down to 110v
single-phase for power tools and discharge lighting, supplied by local
generation from natural gas or diesel engines.

In the UK and other countries with natural gas supplies, domestic lighting
would be by gas mantles, with no general distribution of electricity,
instead household thermo-electric generators could be used for powering
electronic equipment at 50v DC, so avoiding the need for shock protection
measures, and gas for everything else, with LPG cartridges for portable
appliances such as irons, places that did not have gas supplies could use
kerosene or LPG cylinders.


What drivel.

In the UK three hundred years ago the rich used beeswax candles
The poor used "dips", animal fat with rush wicks. Whale and seal oil was
also used.
Coal gas was invented here and became unversal for lighting. There were
initially no mantles, the gas was so impure, the flame was luminous.
Heating was by wood and then coal and coke, mostly open fires.
Gas fires were uncommon.
Most houses only had one room heated.

Electricity when it came was local, sometimes from local mines and
factories.
The national grid was first started in the 1920s.
There was AC, DC and a wide range of voltages.
Even in the 1960s light switches were DC capable and the voltages had only
just been made standard 240v.

Natural gas was only discovered in the 1960s and took some years to be
widely available.