Martin Brown wrote:
On 18/12/2020 13:34, Dave Plowman (News) wrote:
In article ,
Martin Brown wrote:
On 18/12/2020 13:15, NY wrote:
"Andrew" wrote in message
...
If they were migrating geese then there could be
some free roasted xmas dinners :-).

Perhaps those 11Kv lines are a bit too 'saggy' though ?.
How would they stay apart during high winds, which
are expected in that part of the country ?..

https://www.bbc.co.uk/news/uk-scotla...ntral-55334891

That was my thought: if the starlings landing and taking off stretch and
swing the wires so much that they touch, even in cold weather when the
heat hasn't made them expand, then a gale could do the same. The wires
need to be tightened.

It was a hell of a lot of starlings on each wire. Individually they may
not weigh much but on those numbers and all acting in synchrony they
must be well beyond normal design tolerances.

Our local mains in the village is three phase aluminium core wrapped
around a steel hawser. It proved strong enough to support most of the
weight of a tree. The recoil when the tree was cut free was spectacular!

All the poles in the village are now banana shaped with "do not climb"
warning stickers on them.

Would insulating them to prevent this actually cost a lot?

Not really.

Many of the distribution single phase wires in villages start out with
insulation on them but after a few decades it perishes and hangs down in
strips arcing and sparking in the rain when it touches another phase.
Sometimes it was bad enough to trip out the circuit breaker.

Ours used to be like that before they replaced it with the modern
composite aluminium cable with the internal steel hawser.


I dont know all boards did it but SWEB which covered the area where I grew
had insulation on some
11Kv cables where they crossed roads,maybe 33Kv ones as well but I didnt
pass under any of those
while cycling to school. That would be mid to late 1960s and I can
remember when a new line was installed the plastic insulation stood out
because it was green covered.
Also at that time a lot of the pylons of the original 132kv grid.used to
have a safety net of wires
where the lines crossed a road or railway ,that died out some time ago
possibly some of that network was transferred from the CEGB to the regional
boards, occasionally you still see the brackets for them on and old pylon
like this one .

https://goo.gl/maps/FmTkg6u6y27m1kXe9

GH