On Sun, 7 Jul 2013 10:56:36 -0700 (PDT),
wrote:

You see a lot of 3 wire transmission lines across the countryside. The
lines are spaced about a meter apart and are supported by relatively
close-to-the-ground wooden poles which aren't dissimilar to telegraph
poles in appearance.

Most of those are the 11 kV local distribution. Some maybe 33 kV
feeds to local area substations. Look at the insulators, around here
the 11 Kv ones are small, brown with one flange. The 33 kV ones are
larger glass and have two flanges.

The fires grew rapidly and within one minute at the most there was the
most *enormous* flash and ***BANG*** and everything then fell earily
silent. It was one of the most spectacular things I've ever witnessed.

Yes there is *a lot* of energy available on an 11 kV line. Wouldn't
be surprised if the potential short circuit current is measured in
the low kA, so with 11 kV driving it you have 10's of megawatts
available. Put it all in a small space and you get a very big bang...

Plenty of videos of substation fires, arc overs etc on YouTube.

--
Cheers
Dave.