Back in 200o when I was a member of the Scottish Parliamentary Renewable Energy Forum, I did a lot of research into wind and in that research I read that in Denmark it was considered that anything more than about 16-19% wind would destabalise the grid. The reason for this was explained to me by the top Scottish Civil servant (Wilson was his name) who showed me an operating graph of a wind farm and how the power was usually either very low or very high. Contrary to my expectations, wind power doesn’t slowly increase with wind speed. Instead, it behaves like a car with a sticky accelerator – ticking over or full on.
Paradoxically the reason he raised this was because we had been discussing the need for backup storage in order to cope with all the wind. As far as I know, nothing has been done to cope with the variation in electricity from wind, and so it was inevitable that sooner or later we would start to see blackouts.
Then on the 16th April during a very windy evening at 8:30pm as many as 200,000 homes were affected by a power outage. Many immediately suspected that this was due to the high level of wind and the criminally negligent attitude of the Scottish government who have pushed through wind in a wholly reckless way.
Today that suspicion has been confirmed on the Bishop Hill Blog
Readers may recall the story I posted about a major power cut in the North of Scotland last month and the speculation that the underlying cause was windfarms. This has officially been put down to a faulty relay, but today Euan Mearns notes a letter by an electrical engineer in a local newspaper which tells another story:
SIR, I was amazed to learn that a Scottish Hydro Electric transmission spokeswoman said “repairs are being carried out on the faulty relay” that allegedly caused the power cut on April 16 (“works to fend off blackouts”, P&J, May 10).
I have been an electrical engineer for over 40 years and have never heard of anyone “repairing” a hermetically sealed relay switch.
The relay switch operated perfectly on the windy night of April 16 when it detected a sudden surge of voltage and frequency that fell outside acceptable parameters.
A relay switch has two states: on and off. All of these relay switches operated perfectly on the night, independent of the relay switch at Knocknagael Substation which is, itself fed by at least two windfarms, Farr and Moy.
This was what is known as a “rolling blackout”. It is ludicrous to suggest that all lights went out all over the north at 8.30pm exactly. My area went out at 8.43pm when the blast of wind reached Novar windfarm and toggled the relay switch to off to protect its local circuit and so on up the coast.
Grid operators can switch windfarms on and off remotely – if there is a risk of too much wind generating too much “wrong time” low-grade electricity with what is known in the industry as “flicker”. The grid cannot handle more than 10% of flicker contaminated electricity at any given nanosecond and this limit was exceeded on the night.
The operators were caught on the hop. With no electricity, all the windfarms had to be isolated manually.
The spokeswoman goes on to say that they will be making changes to how the protective equipment operates. This is code for shutting down windfarms even earlier in windy conditions so that the operators get more and more constraint payments for not generating when the wind speed is just right.
Andrew H Mackay, Tain
The key here is the phrase: “The relay switch operated perfectly on the windy night of April 16 when it detected a sudden surge of voltage and frequency that fell outside acceptable parameters.”
It is therefore certain (given the letter) that a variation on the grid caused the outage and not a faulty relay as was wrongly stated by John Swinney. So John Swinney clearly misled parliament.
The next question is this: “what did cause the initial power fluctuation?” There are two scenarios – the first is that the cause can be identified and the second is that it was a combination of many factors contributing to it.
We can rule the first, because if a cause were known (which was not wind), then undoubtedly this would have been offered as an explanation and not the false statement about a faulty relay. This leaves us either with another lie about wind a the sole cause, or that the cause was “a combination of factors” of which the high winds on that night must have played a very considerable part. Therefore given the high winds that night, the lack of government honesty and no other plausible explanation, unless & until a full explanation is given identifying a fault (which seems highly unlikely at this late stage), I am prepared to say that this was very likely the first confirmed outage due to the government wind policy.
Finally, it is also very likely that wind contributed heavily to the extent of the rolling blackout as well as the length of that blackout. However whilst the letter suggests this occurred, and it is likely it will occur as we see more and more of these blackouts, there is not enough detail to say to what extent wind played a part or indeed, whether this actually happened in this case