Unbelievably I can't see a discussion thread on this already.
Anyone actually believing that a single transformer/substation fire shuts fully down one of the largest airports in the world?
Mod edit: including a link for context
Unbelievably I can't see a discussion thread on this already.
Anyone actually believing that a single transformer/substation fire shuts fully down one of the largest airports in the world?
Mod edit: including a link for context
Hello Sergio:-
There has to be an independent auditing organization that has the power (without being interfered with by the government) that has the power to force the necessary controlling organization to do the required maintenance work.
If they do their job correctly, they become the most hated organization in the country!
Peter Brooks
An elevated moisture reading in one of SGT3 bushings. I wonder how many others are in the same condition that
NG (National Grid) / NESO (National Energy System Operator) are ignoring or have not dealt with yet? Maybe there needs to be a FOI (freedom of information) request to ascertain this information? Ofgen and the others need to become pro-active on matters
To provide a little balance to this discussion -it doesn't make much difference if the asset is owned by a private company or the public/government- no one likes to do maintenance.
On the public side think of all the health problems caused by mold in social housing.
On a more personal side, who likes to go to the dentist for maintenance work?
Peter Brooks
There's also a LinkedIn comment at https://www.linkedin.com/posts/simoncgallagher_heathrow-neso-powercut-activity-7346083051480707073-KKrU (I've stripped the tracking codes) highlighting that Heathrow should also be taking much of the blame.
[It was their battle to lose, as much by their inability to utilise the multiplicity of supply points]
This is what happens when major national infrastructure is run by for-profit companies. Shareholder dividends come before maintenance.
The same could probably be said about the power outage that happened in Spain recently. Takes Thames water as an example on the verge of bankruptcy and Thames Water paid out £18 million in bonuses to 21 senior managers, with the first payment of 50% of their base salary being made on April 30, 2025
Regulators need to crack the whip and maybe even consider fines to the directors not the company for bad performance
The latest news https://www.bbc.co.uk/news/articles/cly22eelnxjo suggests that National Grid knew there was a problem with water getting into the substation electrics back in 2018, but somehow never got round to doing anything about it. They were going to fix it in 2022, but didn't.
This is what happens when major national infrastructure is run by for-profit companies. Shareholder dividends come before maintenance.
Still does not explain why Heathrow internal network relied on manual switching to re-configure their network.Most
large hospitals have automatic reconfiguration of their own network in event of a fault.
And sufficient on site generation to run the whole hospital.
Surely Heathrow should have the same on their site??
If you mean the airport, with three infeeds, I'd say by the read of it they could (and did within 6-7 hours from memory) but it required manual intervention. Probably this was in part due to SSEN enforcing open points to ensure that their feeders aren't paralleled through the customer's network (usually this means transferrable key interlocks etc).
If you mean the Hyde 66kV SS, the first SGT tripped and the substation did indeed recover using the third SGT which was provided as a running reserve. But the fire caused the second SGT to trip a little bit later either due to fire damage to its control kiosk or exploding bushings, and the third SGT was taken out automatically by the control scheme as it wasn't designed to operate solo.
"Using forensic analysis from both National Grid Electricity Transmission and London Fire
Brigade, this review has seen evidence that a catastrophic failure on one of SGT3’s high
voltage bushings caused a fire to ignite on the supergrid transformer. This was most likely
caused by moisture entering the bushing causing a short circuit. The electricity likely then
‘arced’ (causing sparks) which combined with air and heat to ignite the oil, resulting in a fire.
2.4 An elevated moisture reading in one of SGT3’s bushings had been detected in oil samples
taken in July 2018. According to National Grid Electricity Transmission’s relevant guidance, such
readings indicate ‘an imminent fault and that the bushing should be replaced’. While the
reading was recorded in National Grid Electricity Transmission’s online system, the mitigations
appropriate to its severity were not actioned."
So that is the nature of the network fault, but, and it is quite a big but, why, given Heathrow has 3 in-feeds, could they not switch over to the other 2 and keep going - clearly that is what National Grid expected would happen as they did not consider the transformer bushing a priority - and presumably would have had to power some kit off to change it anyway.
Mike
Thanks Chris.
An interesting read (with some lessons in the detail) although sadly at the highest level does sound like the common "opportunities were missed" maintenance failure.
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