On 18/12/2020 13:25, newshound wrote:
I don't think winds normally cause too much problem on 11kV.

Then you are wrong. Especially near trees. Mind you in the last 20 years
they have cut nearly all the trees back near thenm round here, which has
helped, but gales still cause brownouts


Trouble is,
they don't produce enough corona discharge to keep birds clear.

Neither do teh 275Kv ones, Ive seen birds on those.

On national transmission lines the current they can carry is limited by
sag caused by thermal expansion, so they can carry more power at low
temperatures. A rare example of Sod getting it wrong.

I don't think that is correct either. There isn't much sag before
melting on a hot wire.

In reality losses get too great at high currents - I²R etc etc.




--
A lie can travel halfway around the world while the truth is putting on
its shoes.