Disinformation & the Heathrow Shutdown
The substation fire and the Heathrow shutdown showcase everything that's wrong with today's Britain.
1. Introduction
As regular readers will know, I am not a full-time blogger or citizen journalist - I do not comment on every breaking news story. Instead, I write occasional long-form, fully researched pieces in areas where I have specific expertise, which I think might contribute to better understanding of the truth by key influencers and the interested general public.
So, when I heard about the Heathrow shutdown, “caused by a transformer fire at North Hyde substation”, I refrained from significant comment other than a few necessarily cryptic TwiX posts. Necessarily cryptic because of the TwiX character limits and my own lack of detailed current knowledge of the Heathrow internal and external electricity supply arrangements.
I did not intend to write this note - I did not think it would be necessary and I have many other urgent demands on my time at the moment. But the prevalence of such utter nonsense spewed out by our media and political classes has goaded me into action.
Much has changed since the mid-eighties when I was a young network engineer with Southern Electric (now part of Scottish and Sothern Energy, SSE), with detailed knowledge of the supply arrangements for Heathrow - universally acknowledged internally as our most important customer. Much else, though, has not changed.
In this article I will cover both, as well as a commentary on the fake news story as it has unfolded in the past 24 hours or so, and provide my own brief “arms-length” assessment of the fiasco.
2. How the story has unfolded in the media
As is typical in all such situations in recent years, we have been treated to such a feast of disinformation from politicians, journalists and talking-head “experts”, that it is difficult to know where to begin:
“North Hyde substation represents a single point of failure”
“All three transformers failed”
“The fire also took out the backup generators” (the genius Ed Miliband)
“Heathrow replaced backup diesel generators with biomass” (the genius Richard Tice)
“There is no on-site backup at Heathrow”
“There is no grid redundancy in supplies to Heathrow”
“The UK’s inadequate critical infrastructure provisions make us vulnerable to foreign threats”
As yet, “we” (including me) do not actually know the detailed truth of what happened, or why. But I can confidently report that the vast majority of the political and media narrative is utter nonsense.
Some of the confusion arises naturally, because - for obvious reasons of security - the supply arrangements for such a critical site such as Heathrow are not widely publicised. But that really is no excuse for the woeful, and ongoing, inadequacies in the media coverage.
3. Electricity supply to Heathrow - what has not changed
In the mid-eighties (and before) Heathrow had three on-site intake substations supplied from the local distribution network (not directly from National Grid).
Today, the airport still has three on-site intake substations supplied from the local distribution network. North Hyde - the site of the transformer fire - is not one of those intake substations: One of the intake substations is supplied at 22,000 Volts (22kV) from North Hyde. The other two were, and are, supplied separately - i.e. not from North Hyde. The intent - unsurprisingly - was and is to provide redundancy via alternative supply arrangements sourced from the national grid and local distribution networks. There is no “single point of failure” in this arrangement.
The 22 kV network which supplies the relevant Heathrow intake substation is supplied from the 66 kV substation at North Hyde, which is in turn supplied from the National Grid substation containing the affected 275/66kV transformers. North Hyde is actually three separate substation “compounds” with voltage transformations at different levels (Source: https://www.ssen.co.uk/globalassets/about-us/dso/current-consultations/north-hyde-grid-supply-point---strategic-development-plan---for-consultation.pdf)
Networks operating at the non-standard voltages of 66kV and 22kV were obsolescent in the UK in the 1980’s, so they are certainly at least obsolescent today! Whether this has any bearing on the fire at North Hyde remains to be seen, but there are a couple of points worth brief expansion.
Replacing non-standard/obsolescent/obsolete equipment at substations, while expensive, is relatively straightforward logistically. Replacing miles of underground cables in a significant area of West London less so. While many/most of the substation assets will have been replaced with standardised equipment over the years - e.g. with 132kV or 33kV switchgear operating at 66kV or 22kV - the only choice to “standardise” legacy cables would be to down-rate them to operate at 33kV or 11kV respectively - thus significantly reducing their load-carrying capacity - until an incremental upgrade of the entire underground network is complete.
Alert readers will note the obvious implication that any equipment still rated at legacy non-standard voltages is likely to be at least 50 years old, and possibly significantly older. Whether this includes the failed transformer/s again remains to be seen, but there are good reasons to suspect that it might.
4. What has changed
In addition to the three intake substations supplied from the public network, Heathrow now also has an internal combined heat and power (CHP) “energy centre” powered by biomass, to virtue-signal it’s “green” credentials - and likely (more importantly) save a significant amount of money. Note, however, that this CHP plant does not constitute reserve “backup” power in any traditional sense - it is part of the normal baseload operation of the airport. What it does mean, though, is that the backup represented by the redundancy of external connections is reduced, in principle, in terms of the power shortfall to be supplied via the remaining intake substations.
This all depends of course on everything operating according to plan - assuming the Heathrow authorities actually have any failover plan worthy of the name. More on that below.
The airport also now has new terminals and carries significantly more traffic than it did in the eighties. Whether the internal CHP plant is sufficient to offset the load growth seen at the airport over the last few decades remains - like so much else - to be seen.
The area of West London around Heathrow has also seen significant load growth in recent years - including, reportedly, new energy-hungry data centres with demands comparable to Heathrow itself. Again, whether this has reduced the available capacity to any or all of the three intake substations at the airport remains to be seen. However, in media interviews yesterday, the Heathrow CEO claimed that the two intake substations which were unaffected by the incident at North Hyde remain sufficient to power the entire airport operation - minus, presumably the output of the biomass CHP plant.
5. Arms-length assessment
I do not have up-to-date insider knowledge of the detailed internal and external electricity supply provisions at Heathrow. However, from information that is publicly available, it appears that the basic design is unchanged from the 1980’s.
Whether the age of certain equipment, or the increased risk of “sweating assets” to meet increased electrical demand in the area, contributed to the initial fire at North Hyde is unknown at this point from an outsider perspective. However, these factors will certainly be well understood internally, by the network planners and control engineers at both National Grid and SSEN (Scottish and Southern Energy Networks - the owners and operators of the local 66kV and 22kV network). Everything at these substations is telemetered and logged - real-time loads, oil temperature alarms, switchgear operations and so on.
It should be a matter of mere hours before senior management at both organisations are presented with the full story - so that they can then obfuscate and deflect, as is their self-satisfied perception of their jobs, in subsequent public announcements.
In my opinion, the likelihood that the fire was caused by terrorism, vandalism, or interference from a foreign state is minimal. This is likely to have been an extremely rare catastrophic failure of a massive transformer forming a key part of the support infrastructure for a site of critical national importance.
However, this failure - even with the reported loss of an adjacent “redundant” transformer in the fire, and the apparent deliberate shutdown of a third (second redundant) transformer, should not have caused the closure of Heathrow Airport.
The electricity supply to Heathrow is designed such that it can operate with the loss of a single intake substation. However, that is dependent on the professional competence of those responsible for the internal power distribution arrangements at the airport.
The performance of Thomas Woldbye, the Heathrow CEO, has been woeful in that regard. Interviewed by the media on Friday, he claimed that everything worked as planned, and on Saturday, he boasts that he is “proud” of the airport’s response to this major incident.
The truth of the matter is that the loss of a single intake substation, from three, should have caused no more than a temporary interruption to some non-critical airport systems. All critical systems should be supported with uninterruptible power supplies, comprising short-term battery installations supported by longer-term fast-response on-site backup generators capable of relieving the batteries within a few minutes at most.
Pre-planned switching schedules should then have ensured the seamless transfer of load from the lost substation to the two remaining intakes at the airport, thus in turn relieving the backup generators. The idea, propounded by some, that the airport should be able to run on internal backup generation alone for extend periods of up to 24 hours, is almost certainly unnecessary - and a red herring as far as any root cause analysis is concerned.
Ideally, these switching schedules should be automated, but it is possible that some manual intervention/verification/authorisation be required from an on-duty control engineer.
Airport passengers should have barely been aware of the incident, the general public not at all, and it should certainly not have become the major global embarrassment that it did.
6 Conclusion
At the time of publishing this article, I believe it is unlikely that this incident was triggered by malicious actors. Nor do I believe that there is any direct connection to the Net Zero lunacy.
It is very likely though that there are multiple indirect links. Aside from the additional complexity for planners and control engineers of dealing with non-standard 66kV and 22kV network design - technical factors like fault levels and protection settings will be different, but should not cause a problem for properly competent engineers planning and operating the system - the increasing prevalence of wind and solar “renewables” embedded within the network bring several challenges of their own. I would not be surprised at all to hear of a protection discrimination failure, or some such, in any eventual official report.
I am certain however that there is a connection to the wider Long March “Woke” madness that has totally gripped the UK. The DEI, don’t-rock-the-boat, virtue-signalling culture that has captured our professional classes in all industries, means that people like me - who “ruffle feathers” in the complacent centres of group-think that our major public and corporate bodies have become - are persona non grata in today’s world.
If it transpires that short-term backup arrangements within the airport were indeed inadequate, or that pre-prepared switching plans for load transfer were not fit for purpose, then it is also very likely that cost-saving “efficiencies” will have played a significant part - and heads should roll.
The end result of all this is incidents such as the Heathrow farce, and the root cause is the same as that of all our national woes: Uncontrolled immigration, the insane dash for Net Zero, the crazed response to Covid, the failure of HS2, the dysfunction of our NHS, and so much more.
We can therefore look forward to many more of these catastrophic failures in the coming years - not least, an increasing prevalence of far more widespread blackouts, as the impacts of our descent into Woke madness increasingly hit home.
Until and unless we finally get some sane grown-ups back into the mix of politics, and senior public sector and business management, we are lost.
Let this ridiculous, entirely avoidable, incident finally be the wake up call that Britain needs.
I’m retired now from NG transmission and this never was my patch, I think the closest I got was some protection equipment work at Iver maybe 25 ish years ago so the only insight I have is what’s been in the press and access to the published transmission system maps which for some reason omit North Hyde completely. In fact I’m really struggling to find any other omissions elsewhere.
I can’t believe the bollocks sprouted by the media and ‘experts’ about this incident although it’s only to be expected!
The total lack of fire separation barriers surprised me, after the massive supergrid transformer fire at either Rochdale or Padiham in Lancashire in the late 1980’s lots of barriers were installed together with increased height bund walls, & fire suppression systems. As far as the North Hyde site is concerned, In the footage and on Google earth, for the one that caught fire you can see rigid busbars from the transformer bushings crossing over the internal access road and around the relay rooms into the lower voltage compound. The western and immediately closest circuit to the one that caught fire looks to cross the road into the compound on a catenary strung from an overhead gantry, and the eastern, most right hand one with large separation from the other two is possibly terminated in a cable sealing end, destination unknown, it could be another DNO substation, or the far side of the North Hyde 66kV/22kV site.
The 275kV busbar sections would in normal circumstances be run split so you’d have two 275kV/66kV transformers effectively on one 275kV feeder, and the remaining 275kV transformer on the other feeder. The 66kV sub with at least two sections and possibly more would then, in normal circumstances, require a double circuit failure of the HV side to cause a total loss of supply (a double circuit feeder fault) At the far end of the 275kV feeders at Iver they’d be on separate busbar sections and so the likelihood of loss of both supplies is quite low but not impossible.
The windings of the transformer are enclosed in oil, circulated and cooled by external coolers (radiators) If there was a transformer fault it might be preceded by the detection of gas being produced within the oil as it decomposes. If this is gradual then in the first instance generate an alarm, normally resulting in a site visit and an oil sample being taken for lab analysis. A rapid production of gas by a failure resulting in an internal arc would result in lots of gas being produced, in those circumstances the transformer would be automatically disconnected from the HV (275kV) supply using a circuit breaker (a device that can break load and fault current) and then automatically disconnected from the LV (66kV) load using a disconnector (a device that isn’t intended to break load and fault current) Hopefully this occurs rapidly without disruption of the transformer tank and cooler bank. But a large overpressure would be relieved by burst discs and oil would end up hopefully within the oil containment bund.
So following the transformer failure, and assuming there is no collateral damage it would still leave the entire 66kV/22kV sub still serviceable, possibly with some loss of supply from bars fed by the failed transformer. At this point reconfiguration to maintain essential supply to Heathrow could be relatively easy.
But if a catastrophic failure of the transformer or cooler bank happened with oil spraying or misting onto live conductors it could ignite.
That’s a holding situation but as the fire progresses the closely sited transformer would at some point either trip on fault maybe with bushing contamination from the combustion products or with winding temperature, or when the extent of the incident became visible it would be manually switched out of service.
One thing to note is all circuits at 66kV and below leave via cable regardless
There are still 66kV networks around elsewhere, off the top of my head, in the North East (Hawthorn Pit, Hartmoor, Lackenby, West Bolton & Norton) and in South Yorkshire (Thurcroft, West Melton & Thorpe Marsh, plus a handful more). All were associated historically with coal mining
Plus the North East has quite a bit of 20kV (yes 20 not 22) lines such as in and around the Hexham area (there was even a new 275kV/20kV sub built on the cross Pennine west of Newcastle route from Stella West to Harker about 25 years ago, named Fourstones)
As an aside, on the previous Friday, the 14th March at 0851 three units near simultaneously tripped at Drax, one on its own and then five secs later two more 1887MW loss of generation. Virtually nothing said anywhere. No lightning activity. No press releases from NESO or Drax plc. Now it could be someone messing up preparing for testing and there is an internal enquiry ongoing but losing generation spread over at least two and possibly three busbar sections is very strange. The frequency dropped to 49.667Hz. Data is visible on elexon. I do have screen caps.
I know very little about electricity supplies so this has been illuminating & fascinating to read. Thanks. The unfortunate facts about old kit not lasting for ever are well known.
The ever increasing demand on all the UK infrastructure & a plan to address this - water, land, roads, power, housing - is rarely acknowledged publicly. At least not in a mature rational discussion. I have so little confidence in those in power to enable this without media meltdown I end up & shrug my shoulders & hope someone skilled & competent who genuinely know what they are doing will sort it out. I wasn’t going in or out of Heathrow at the time - so I’m OK Jack.
I guess we have more of these sorts of catastrophic failures to come.