Thursday, 12 May 2016

Network Stability Problem: A case of jargon overload

Emily Gallichan ‏@EmilyGallichan  May 9

Jersey was liberated from power temporarily today! Wonder what caused it? #liberationdayunplugged #jsypowercut

Ryan Morrison ‏@upyourego  May 9
Taking re-enactment to a whole new level by doing it without power #LiberationDay #jsypowercut

Jersey Garrison ‏@JerseyGarrison  May 9

Sorry to anyone affected by #jsypowercut we were testing a new weapon which required more power than we expected.

Jersey Electricity apologises to islanders after a power cut disrupted yesterday's liberation Day celebrations. Chief Executive Chris Ambler said: ‘The Normandie 2 undersea cable was at the time out of service for planned maintenance by grid operator RTE in France so Jersey and Guernsey were being supplied from the Normandie 3 cable. Unfortunately, a network stability problem led to a complete loss of electricity supply from Normandie 3 at I 1.06am leading to an Island-wide power cut in Jersey and widespread power cuts in Guernsey.

Constable of St Helier, Simon Crowcroft, sounded rather annoyed on the radio yesterday when he described the apology above as inadequate and wondered if we could be told the real reason rather than making use of spin exemplified in the mysterious phrase “network stability problem”.

What is so striking about that phrase is that if you Google for the phrase “network stability problem” and the phrase “power cut”, you get exactly three results, all of which refer to the power cut on Liberation day, and are quoting Mr Ambler.

It is not exactly a Googlewhack, but it is remarkable and suggests that the term was coined by Mr Ambler at a moment’s notice to cover the cracks in what went wrong.

We now have a rather more detailed explanation:

Chris Ambler  told the BBC the Normandie 2 cable was out of service due to planned maintenance leaving the Normandie 3 cable to supply both Jersey and Guernsey.

"The system was stable, but demand was increasing pretty steadily and more strongly than we'd anticipated." Normandie 3 then "tripped out" to prevent an overload, he said.

I had just turned off a light upstairs, and come downstairs, and just as I turned on the kettle, the power went off. At first I thought it was an internal fuse, but then I realised it was a power cut. Was my kettle the straw that broke the camel’s back and caused Normandie 3 to “trip out”?

But on a more serious note, does this mean that Normandie 3 on its own is insufficient to meet peak demand on electricity? After all, the maintenance was, as Mr Ambler pointed out,  not carried out at night (when lighting and cooking can cause spikes in demand) or in winter when demand is higher.

Are we now dependent on having both cables live to cope with peaks in demand? And as a supplementary, have we enough generating capacity locally to manage if, for some reason, we lost both connections if there were problems (as has happened) with the French grid?

Chief executive Alan Bates in Guernsey made it clear that Guernsey cannot rely on just one cable for its demand: "We used only Normandie 3 to import electricity from France; and supplemented that supply with some on-island generation."

The external supply of power from France means that we can grow the population beyond the capacity of local power generation, but it comes with a price, and that price is the occasional outage of the system if those power conducting umbilical cords are cut, either on the sea bed or at the French end.

Mr Ambler said: “"We need to now review this, to look in detail at what went wrong." 

"It is not yet clear what caused the fault, aside from the fact that it originated from the CIEG cable network and was not related to the works taking place in France.”

New Dictionary Definitions:

Network stability problem: power cut caused by unknown factors.

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