Power failure in central London, May 12th 2025

[wanderingriver]

At the time of posting, London Underground and the Elizabeth Line are experiencing a power failure. Fully suspending the Bakerloo Line and part suspending other lines.

Image description: Screenshot of the TfL Status webpage on an iPhone. The text on screen says, "Bakerloo, Suspended, Entire Line", "Elizabeth Line, Part Suspended Paddington to Abbey Wood", "Jubilee, Severe Delays Entire Line, Part Suspended London Bridge to Finchley Road", Northern, Part Suspended Euston to Kennington, Stockwell to Morden".

 

[Horizon22]

Yep several lines are going down, all for the same reason. I would suggest more are currently impacted, but LUCC are currently unable to deal with the volume of service status requests and inward calls.

All very surprising considering these are often differing power supply systems, especially where the Elizabeth line is impacted opposed to certain Underground lines. Or there is more connectivity than it appears. Mostly south of the river impacted.

 

[Watershed]

The reference to a power outage in south-west London makes me wonder whether it's related to a HV connection at the erstwile Lots Road power station?

Looks like TfL's status webpage is currently down, though the API used by TfL Go and other apps is still working.

 

[DavyCrocket]

I hope that the LUCC is ok and it’s dissappointing that they are failing to meet demand. Will lessons be learned?

 

[brad465]

I'm guessing that backup power station London Underground have in Greenwich can't help here (or if it can takes a while to fire up).

 

[Mojo]

I hope that the LUCC is ok and it’s dissappointing that they are failing to meet demand. Will lessons be learned?

Who is failing to meet demand?

 

[Horizon22]

I hope that the LUCC is ok and it’s dissappointing that they are failing to meet demand. Will lessons be learned?

I don’t think they are after all. It is only the lines first advertised actually disrupted and then a few more on top. Even then, if you suddenly have X number of internal calls within a few minutes there isn’t infinite people to answer them & calls stack. Such occasions are very rare.

 

[aaronspence]

The number of potential trains stuck in tunnels simultaniously.. they can't deal with it all at once, Maybe some lines were shut down even with power just incase?

 

[Dstock7080]

The reference to a power outage in south-west London makes me wonder whether it's related to a HV connection at the erstwile Lots Road power station?

Lots Road closed some years ago.
Back-up comes in limited form from Greenwich

 

[Mojo]

I'm guessing that backup power station London Underground have in Greenwich can't help here (or if it can takes a while to fire up).

That isn't the purpose of Greenwich Power Station. As per BBC News there is no loss of power

It is understood to have been caused by a power outage in south-west London which happened at about 14:30 BST. Power has since been restored, but delays and line suspensions are still ongoing.

 

[BruceTee]

Just traveled through Embankment on the District Line at 3PM. Lights on platform all working. We were advised at Temple that Embankment was closed.

 

[LLivery]

The BBC is reporting that LO West Anglia was suspended because of it. Realtime doesn't seem to confirm that, though

 

[Thirteen]

Odd the SSL weren't suspended aside from Embankment being closed nor the Central or Victoria Lines, maybe different power systems in place.

 

[Horizon22]

The number of potential trains stuck in tunnels simultaniously.. they can't deal with it all at once, Maybe some lines were shut down even with power just incase?

There was a power surge reported which caused a number of assets across TfL to fail. This has all mostly restored although Bakerloo is still suspended. Some lines will remain “suspended” until a steady flow of service (even if limited) can be confirmed.

 

[philosopher]

Early this afternoon, there was an approx. 1 second power cut at my office in Soho, Central London. I suspect this could be related to the power supply issues on the tube and Elizabeth Line this afternoon.

 

[didcot_watcher]

National Grid Transmission say they had a very brief fault that may have caused voltage suppression on the DNO networks.

 

[BJames]

The BBC is reporting that LO West Anglia was suspended because of it. Realtime doesn't seem to confirm that, though

This was reportedly due to a lineside fire between Clapton and Tottenham Hale:

All lines have now reopened following an earlier line-side fire between Clapton and Tottenham Hale. Trains running to / from London Liverpool Street, and between Stratford and Tottenham Hale may continue to be cancelled, severely delayed by up to 45 minutes, revised or diverted via Seven Sisters.

Incident: LondonLiverpoolStreet | National Rail

Lines reopened: disruption to / from London Liverpool Street until the end of the day. Find details of all current incidents on National Rail Enquiries.

www.nationalrail.co.uk

Having just travelled on the line I was pleased that these lines had reopened, saving me a diversion!

 

[LLivery]

This was reportedly due to a lineside fire between Clapton and Tottenham Hale:

Incident: LondonLiverpoolStreet | National Rail

Lines reopened: disruption to / from London Liverpool Street until the end of the day. Find details of all current incidents on National Rail Enquiries.

www.nationalrail.co.uk

Having just travelled on the line I was pleased that these lines had reopened, saving me a diversion!

Right, that makes far more sense!

 

[Gerald Fiennes]

So, what happened? A power cut that wasn't a power cut, according to NGT, but presumably enough of a frequency/voltage event to trip some of the modern signalling/ATO systems? (Similar to the 2019 Thameslink failure, when c.40% of the C700s failed in traffic once frequency dipped below 49.5Hz rather than holding out to 49Hz (which was thought to be be spec...))???

 

[GFE]

Note the Bakerloo is old signalling (& trains with no ATO) but has some life expired Electronic/computer based kit with associated vulnerabilities of designs of that era.

 

[bluegoblin7]

The issues differed from line to line - some were signalling, some were traction power, some were other assets meaning it wasn’t safe to keep running trains.

As ever, even a momentary blip can have wider reaching results due to the failure safe and safety critical nature of the tasks. The more trains involved also means an incident becomes more protracted.

I’m actually impressed at how quickly services started moving again on some lines.

 

[didcot_watcher]

I would expect they need to look at how it could ride through such a blip.
Signaling look at which centers had an issue.
Traction supplies, I suspect some of the rectifer sets may have had damage.

 

[bluegoblin7]

Most modern signalling systems have uninterruptible power supplies which mitigates the impacts. London Underground’s power supply feeding arrangements are also incredibly robust and can cater for most blips.

There’s only so much that can be done feasibly, especially when the issues originate from a third party.

As I find myself saying a lot recently: would you be happy for the inevitable fare increase to ensure zero downtime? I wouldn’t.