Another power question (as shown by GridWatch)

[whisky-dave]

I've seen a similar thing happen in Brighton with telegraph wires and trainers it's so sad.

[The Other Mike]

Top rated in the UK is capable of 170 deg C continuous, many are 90 deg C with short term 30 minute ratings in the region of 125 deg C.

There are conductors outside the UK rated up to 2.8kA capable of continuous operation at around 210 deg C with short term up to 240 deg C

[The Other Mike]

The high temperature conductors are utilised at transmission system level not distribution. I can't recall seeing birds perched on anything rated above 33kV

[The Other Mike]

Because they are designed and erected with the right amount of sag such that under their maximum permissible current carrying capacity in the highest ambient conditions they will not even come close to infinging the safety distance, which is considerably more than would be needed to initiate an arc.

[newshound]

You can often hear corona discharges, especially in damp weather and at coastal sites (salt deposition leads to tracking across insulators). Vegetation clearance is monitored at least annually, IIRC.

Back in the 1970's, the CEGB was very interested in what were then called Expert Systems, what we now tend to call artificial intelligence software, and a number of prototypes were developed. The only one which was successful was one to predict the best use of herbicide, to prevent encroachment on transmission lines. It sounds mundane, but good management of this is very cost-effective.

[newshound]

You don't see them on supergrid lines, IME. I think we were really talking about 400 and 275 kV lines which can run close to their limits.

[Chris Hogg]

A new slant on the phrase 'district heating'! In lighter moments, I do wonder if all this global warming isn't a consequence, not of the CO2 itself, but of all the energy being released in the generation of that CO2. It all ends up as heat, after all, and as the world has become increasingly industrialised over the decades and centuries, we've been releasing more and more of it; heat, that is.

[charles]

some time ago - could be as long ago as 50 years - someone had the bright ide of breinging grid cable into central London on the be d of the Grand Union Canal. It was found to heat up the water significantly giving rise to an enormous amount of algae.

[Mike Tomlinson]

En el artículo , Martin Brown escribió:

presumably that's why some of them have brightly-coloured marker balls (oo-er missus) attached at intervals.

[Huge]

[17 lines snipped]

A bloke knocked on the front door here over the summer and asked if we'd mind if they cut the hedge under the power lines (I think they're only

240V and supply power solely to my house). Mind? I was bloody overjoyed. He said they do it every 5 years.

Couple of weeks later some tree surgeons turned up and actually cut it.

[Bob Eager]

I was walking the towpath near Regents' Park back in April 1997, and had to abort the walk because they were digging up the towpath for grid cable.

I went up Primrose Hill instead.

[tony sayer]

In article , Mike Tomlinson scribeth thus

There is one near the Burwell maim substation near Newmarket where down a farm track we used to be able to pull sparks some 2 inches long from a rod a well insulated one mind, held around 8 foot high, large ish sparks too in wet weather;!..

[tony sayer]

In fact it's on the NatGrid website clearance distances from 132 and

400 kV lines under varied circumstances one of them wasn't that much IIRC!..

[Mike Tomlinson]

En el artículo , tony sayer escribió:

Holy crap. Rather you than me :)

[Chris Hogg]

Fluorescent tubes held vertically under a HV power line will light up.

[dennis]

I have been in a thunderstorm where the rain drops were bursting with little blue lights as they landed. I moved away fairly quickly.

[dennis]

That's the heat island effect. It probably is the cause of the heating being monitored to a large extent. However they have now corrected for it and still claim there is a lot of warming. There are debates about what the corrections are and whether they are correct.