This is quite alarming, but as Dr. Leif Svalgaard explained in his email tip to me, “…in this case, probably justified”.
Here’s the story from the Independent:
Officials in Britain and the United States are preparing to make controlled power cuts to their national electricity supplies in response to a warning of a possible powerful solar storm hitting the Earth. In an interview with The Independent, Thomas Bogdan, director of the US Space Weather Prediction Centre, said that controlled power “outages” will protect the National Electricity Grids against damage which could take months or even years to repair should a large solar storm collide with the Earth without any precautions being taken.
…
The aim of the joint US-UK collaboration is to improve solar weather forecasting to a point where it is possible to warn power companies of an imminent storm. There is a feeling that if a “category 5” solar storm – the biggest of the five categories – were to be predicted, then taking the grid off-line before it is due to hit Earth and letting the storm pass would be better than trying to keep things running, he said.
Read the full story at the Independent here, they say they Met Office will be involved.
Of course, so far, the sun has been a bit of a limp noodle, but even a weak head-on CME aimed at Earth can wreak havoc with the dainty micro-electronics we use these days. Even though the overall solar activity has been low, we have witnessed impressive flares, such as this one on June 7th and this one on Feb 14th: Sunspot group 1158 produces an X class solar flare.
For some people the world would end if their computers or personal telecommunications were solar deep fried, so this is probably a good idea. Of course, with the Met Office track record for terrestrial forecasting, I worry they’ll forecast a “BBQ solar event”, nothing will happen, and then nobody will pay attention when it really counts the next time. Let’s hope it doesn’t become the boy who cried Wolf numbers.
“The problem can be remedied by temporarily increase the earthing impedance at the neutral earthing point or even temporarily disconnect the neutral if possible. Large serial capacitor banks in the transmission line is the best remedy for GIC.”
It would need to be a very large capacitor to withstand the potentially large DC potential. You would not want to be near it if the DC breakdown voltage was exceeded allowing the total charge to be explosively released.
Another possibility would be to insert large (L) chokes across the transformer. Either approach would be very expensive.
They can happen any time.
I agree. Softening us up for future outages caused by “alternative energy” failures.
Never mind the solar flare problem. The National Grid in the UK have today stated that wind power is so erratic that they cannot cope with rapid inputs so turn the turbines off. This puts more reliance on Fossil Fuel producers, which is as it should be.
To dave 1264
There are such capacitor banks already in use to reduce the effects of the GIC and also in order to enhance the power angle of long transmission lines and thus increase the transmission capacity, expensive, yes, but the payback time is short.
http://www.nokiancapacitors.com/documents/03%20-%20products/systems/EN-CS02-10_2006-series_capacitors_(short).pdf
Hans
OH6MY
sibeen said at June 14, 2011 at 1:24 am:
“Massimo, it is a DC current that is induced into the grid. Transformers really don’t like DC being injected into them and have a tendency to overheat, explode, melt down. Not what you really want to happen when getting a replacement may take months.”
If the grid has the 4th ground conductor as most of the Italian grid has, I don’t believe there is any DC current in the transformers at all. I write that, because the surge induction is the same on every conductor, so the resulting current for the network is zero. The problem arises if the grid doesn’t have any ground conductor, because the Earth ground behaves very differently than the grid conductors and when the induction wave floods that electric network a potential could come up at the two ends of the grid. This could be a big problem for the transformers because in that situation an high current surely flows through them.
I fully agree with the explanation of Hans Åström about what happen in the transformers, but instead of insulate the earthed neutral I believe it should be better the 4th ground conductor which ties the two grounds at the grid ends to the same potential. Anyways I’ve to admit that this is not my specific field, so I don’t know how much it must be sized that 4th conductor to work that way.
By the way Hans, if OH6MY is your callsign, here is IK1IZA.
73
John Marshall – could you point me to that Windfarm/National Grid story please.
Thanks
This is no news. In an era of hysteria, when there is an administration whose middle name is hysteria, any theoretical possibility of harm will be played to the maximum. It is the Precautionary Principle at work. In addition, when the administration has strong socialistic tendencies, the remedy chosen will maximize federal government control over all private resources. It was inevitable. As are many other things coming down the pike.
If the administration did not seize each such opportunity, the feeling of regret would be so great that some of its members would go into terminal depression. The Precautionary Principle again.
What do the met office know about the sun’s activities?
They can’t even manage to accurately grasp the immediate local & regional weather here on earth, let alone mid-long term climate change trends, let alone sun flares!
It is clearly a funding grab where you may as well instead pay some old hobo £1bn to guess & speculate instead of paying this bloated public sector funded organisation to do the same!
to Massimo
Yes OH6MY is my callsign although I’m not very “radioactive” these days.
The problem is that the fourth (neutral) conductor carries GIC the same way and in the same direction as the phases because it runs he same path as the phase conductors and is subjected to the same changes in the magnetic field of the earth.
The return path is the earth itself. I think you do not have those problems in Italy because you hardly encounter Aurora down there. Here in Finland we have those GIC problems but there is introduced capacitor banks in our 400 kV system.
We even simulated the influence of GIC by running DC into the neutral of a large transformer using a DC-arc welder and the transformer started moaning at very low neutral DC currents!
Hans
OH6MY
GaryP says:
June 13, 2011 at 6:03 pm
Gary’s right. Solar storms don’t fry personal electronics. They fry transformers with many miles of electrical lines connected to them where the induced DC current on the lines saturates the core of the transformer and makes it overheat. The big transformers at power sub-stations are typically made on demand and have manufacturing lead times of several months. Protecting them is simply a matter of opening a circuit breaker so the DC loop is broken. I’m not sure why these transformers don’t have built-in protection against excessive DC current in the core but evidently they do not. In any case as others have mentioned there is no significant inventory of large transformers sitting on the shelf nor any excess in manufacturing capacity so in the case of a huge spike in demand because tens or hundreds of thousands got fried all at once in a big solar storm it would take years to replace them all. Just restoring critical power for hospitals and personal medical equipment, refrigeration, water pumps, sewer pumps, and pumping fuel out of underground tanks at gas stations would take weeks. Massive electrical outage across half a continent lasting for weeks would be the biggest disaster in recorded history with a death toll of many many millions.
For a planet filled with people of nations wanting to go green a class five event that would take down national grids should be viewed as a good thing; so why worry? Many of those leaving messages say these events can not happen yet so many await the 2012 predictions of the Mayans or even of the semi-lucid so claimed prophets who claim the end is near.We should be talking about when not if for mush more than the Internet will be gone. There is a chance that solar flare could cause an event so heinous as to destroy life on the side facing the sun. This would entail horrendous consequences for those who survive. perhaps we should work harder at being our brothers keeper and preparing for what ifs and maybe to insure we all maintain a good quality of life.
Well then, it seems there may be a problem. Let me ask the knowledgeable posters: If the problem is that large DC currents will overheat transformer cores, then why wouldn’t the circuit breakers trip, just as they do for a ground fault?
Hans Åström said at June 14, 2011 at 6:16 am:
“The problem is that the fourth (neutral) conductor carries GIC the same way and in the same direction as the phases because it runs he same path as the phase conductors and is subjected to the same changes in the magnetic field of the earth.”
Hi Hans.
I repeat myself, I’m not an expert in the field, I work more with microprocessors and medium power industrial devices such as IGBTs and SCRs. What I was suggesting is because as you say the earthed ground conductor is subjected to the same magnetic field changes of the other conductors. If its impedance was enough low to handle the induced current, it should be a good way to keep the two neutrals at the same level of the three phases and avoid the very low frequency current into the transformers.
The problem maybe the “if” I used because I know the very low ground impedance at that frequencies.
Anyways I’m not very “radioactive” too, just some little VHF and UHF chats by night 🙂
Info on Wind Turbines and UK National Grid, seems the network upgrades have not been keeping pace with the increase in Wind Turbine farms
http://www.windbyte.co.uk/
and
http://www.reuters.com/article/2011/06/13/us-britain-transmission-natgrid-idUSTRE75C2PY20110613
The more we learn about the universe the more we realise how small we are in comparison to all the huge natural forces that could crush us in an instant. The ignorant peasant can complacently assume that his small world is the centre of the universe. The citizen of a modern technological society is anxious because he or she recognises how vulnerable we are. But if ignorance is bliss, knowledge is the opportunity to prepare.
Thanks for the info, les frances!
I nominate ROSS’ comment near the very top for about the FUNNiest thing I’ve read, all week. Outstanding.
A quick search of this thread did not yield up the key word “islanding” … the proper term for segmenting the ‘grid’ into smaller, manageable parts sans the ‘tie lines’ that are normally used to transfer power to or through at the transmission level …
Prior writings on the subj (with reference to power distribution company internal training material):
Largest space weather storm in at least four years
Posted on February 18, 2011 by Anthony Watts
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Dave, are ya justs plain impervious to the input from others?
This post was to you back on: February 19, 2011 at 4:44 am
I am beginning to think there is ‘thick’ and then a category after that called ‘Dave thick’ .. just sayin y’all …
.
This is not a case for speculation, but more on examining the damage that has been done in the past when planning to handle such events was not undertaken … witness the damage pictures within this training document here:
http://www.pjm.com/training/~/media/training/core-curriculum/ip-ops-101/ops101-weatheremer.ashx
Slide #14 is particularly gruesome (transformer damage).
Note also other slides address the physics of what takes place.
.
I know it’s difficult, but we have to try to educate those desperately needing it.
Dave Springer: “The big transformers at power sub-stations are typically made on demand and have manufacturing lead times of several months.”
No, the lead time is about two years. There are NO manufacturers in North America any more. The last new large transformers built and installed were on Hydro-Quebec’s DC system, imported from Europe. In Canada alone there were three manufacturers of large power transformers at the turn of the 1990s, but there’s been no significant transmission construction in the past 20 years.
One account (from 2005) I could find showed a documented ‘dip’ in signal strength of maximally 3 dB; this is not a significant amount. The travel of GPS birds from horizon can show this much change, some owing to the receive antenna’s inherent pattern anomalies, and others owing to temporary obstruction such as due to an aircraft’s tail and/or rear stabilizer structure:
Note: In most GPS applications 20 to 30 dB (factors of times 100 and times 1000 respectively) fade margin is budgeted for as shown in this GPS Link Budget Analysis, so 3 dB is well within the limits of coping.
Also be advised the present architecture of GPS is not the end of the road; from the
FAA.goc website:
.
Quoting Colin:
“I know it’s difficult, but we have to try to educate those desperately needing it.
Dave Springer: “The big transformers at power sub-stations are typically made on demand and have manufacturing lead times of several months.”
No, the lead time is about two years. There are NO manufacturers in North America any more. The last new large transformers built and installed were on Hydro-Quebec’s DC system, imported from Europe. In Canada alone there were three manufacturers of large power transformers at the turn of the 1990s, but there’s been no significant transmission construction in the past 20 years.”
The situation is not that bad.
Typical lead-times for large power transformers up to 63 MVA are 5 – 7 months, 63 – 100 MVA 6 – 8 months, 100 – 250 MVA 7-12 months. Very large generator transformers 250 – 1000 MVA 12+ months.
There are some substantial transformer producers still in NA, ABB in St Louis and Waukesha in Wisconsin and North Carolina. ABB also operates a factory in Varennes, Quebec Canada and a transformer service and repair shop in Guelph, Ontario Canada.
There are although only some few manufacturers of transformers for HVDC application and the most substantial of them are located in Europe, ABB Transformers in Ludvika, Sweden might be considered as the most “Hi-Tech” of them all.
Hans
OH6MY
I used to distribute McGraw Edison products here , mainly auto re-closers but some transformers.
Are they out of the transformer business now?
_Jim said June 14, 2011 at 8:16 pm
“This is not a case for speculation, but more on examining the damage that has been done in the past when planning to handle such events was not undertaken … witness the damage pictures within this training document here…”
Thank you Jim for the nice and useful link.
As you can see in slide 7, it demonstrates that me and Hans were right about the transformers problem.
The damaging currents flow through the grounded neutrals. As Hans suggested a capacitor in series to those grounding could help reduce damaging because it increase the ground impedance at those very low frequencies the induced currents flow (someone call them DC currents, but I agree with Hans, they can’t be DC currents because a steady magnetic field can’t induce a DC current ).
What I was arguing is that in case you connect a 4th conductor which connects together the neutrals of the two transformers at the ends of the grid, it could help reduce the very low frequency current flow into the transformer coils. That because it should have a lower impedance than the coils which will be paralleled to it.
Massimo
If we are only talking about primary distribution system transformers, it might be practicable to provide a complete set of backup units in cold standby, funded over the average time between events or failures. Replacing all the endpoint pole transformers would be another issue altogether.
I do not think modern society could tolerate a one to five-year power blackout.