OT: Heathrow substation final report

Hanlon's Razor applies again! Unless, of course, it was Russian moisture... :-)

I blame climate change, Donald Trump , or cyclists or maybe the SNP.

The BBC made a moger of explaining what a bushing was, but I see they've removed that bit.

Brian

From the BBC:

"So when they identified those moisture levels back in 2018, what should have happened is that the transformer should have been taken out of service for a short period of time and that fault effectively repaired," he said.

"That was missed. The moisture got worse over time and ultimately that's what caused the fire to happen. The story of our report really is probably one of missed opportunities."</quote>

I hope customers and the suppliers learn that they need to have some understanding of each others roles instead of going for what I call "sub system optimisation", which loosely translated means "optimising our profits".

It's extremely strange. Whenever I have reported a network fault they are out there like a shot usually.

My experience is that my electricity supplier is very good at short-term fixes but not so good at long-term fixes and checks for recurring problems.

We went through a phase of getting brief (*) 2-second power breaks every summer, especially after it had been windy. Sometimes they would happen there or four in the minute, then there would be a gap and then another flurry of them. I diagnosed the problem almost immediately - overhanging tree branches blowing in the wind, touching the high-voltage 11 kV or 33 kV lines and tripping a circuit breaker which either reconnected or else triggered a switch over to a different HV feed.

The electricity company always acted surprised, as if they would never have expected this in a million years. One year the response was "well, we cut back those trees last year. They've *grown* again." As if the concept of trees growing was new to them. Another year they blamed it on cattle using a wooden pole as a scratching post - plausible until the farmer who owned the field replied on the village Facebook group that there hadn't been animals in that field for the whole year.

Strongly-worded letters to CEOs seemed to do the trick. The only power cuts we've had since then have been planned ones that we've been notified about in advance, and a long one after a violent storm that affected a wide area. Those are understandable and forgivable, but brief repetitive faults are down to poor maintenance and not cutting back branches *before* they get anywhere near causing shorts to earth.

(*) Just long enough that all computer equipment needed to reboot, and causing non-recoverable problems with our mesh wifi network which sometimes locks-out some nodes if they are all turned back on simultaneously - they need to be turned on in a special sequence otherwise they stall as they try to auto-negotiate free 2.4 GHz wifi channels. I was considering buying UPSes - plural, because each node in a different part of the house would need its own. That would need four of them: three for "child" nodes and one for the "parent" node and the router.

Round here they do exactly that.

Well yes. Its a tossup as to whether my CH system comes up clean or not. House Server obviously does not and I leave it down until the power is definitely up

That has the whiff of "different budgets", with the longer term one being bleed dry for the shareholders. (See also: water).

Indeed. When I got my supply undergrounded so I could build a second storey where the wires had run, I had to stump up part of the bill, but not all. There was 'some budget for undergrounding'.

They cost of maintaining 11kV and 33kv above ground makes sense of putting it underground wherever possible, but the capital budget to do that doesn't exist.