Great Western Coffee Shop

From Motherboard (http://motherboard.vice.com/en_uk/read/europe-is-prepping-their-railways-for-extreme-space-weather?)

In short no !
Electric railways are inherently very vulnerable to solar storms since they unavoidably involve long insulated electrical conductors.

Diesel or steam worked railways would be less vulnerable as regards motive power, but would still be severely affected by induced currents interfering with signalling equipment, and possibly destroying the modern electronics on which todays signalling relies.

Even heritage lines could suffer some damage, voltage induced in the rails could be dangerous to touch and might start fires.

Other infrastructure is also vulnerable to damaging currents induced in long conductors, the national grid would probably suffer severe damage, but long telephone lines, long metallic pipelines, and even long fences of metallic wire would also be at risk.

There has never been a truly severe solar storm in the modern era. The last one was at the very beginning of the railway age and little if any damage was caused, except to telegraph equipment, railway related or not.
Reliable reports referred to telegraph instruments catching fire, to operators receiving severe electric shocks, and messages being sent and received despite disconnecting the batteries.

Presumably only long metallic telephone lines - I assume fibre-optics would be OK. 

Yes, most * fibre optic telephone or data cables would be unaffected by severe solar storms, as would be "line of sight" radio/microwave links.
Both modes of communication would of course be vulnerable to a general loss of power due to national grid damage.

*The exceptions would be firstly any fibre optic cables with metallic covering or armouring that is continuous over some miles, induced currents in this armouring might produce enough heat to damage the optical fibre.
Secondly, fibre optics run in close proximity to power cables would be damaged by any fires started by induced currents in such cables.

You are assuming we have any electricity with which to power all the surviving equipment! Our already heavily burdened National Grid would collapse under the surge, and would take quite a few days to reset, if not longer. On the plus side, many wind-powered subsidy generators would die. Luckily, there is CCGT back-up power for all those, so we wouldn't really notice them missing. If we haven't demolished all the coal-fired power stations by the time it happens, we could start those up again within a couple of weeks, even if it means using the railways for coal only for a short while.

It will be a mess if it happens, but we will get over it soon enough. The cost of trying to proof everything important for what is a very rare event would be astronomic, and may not even come close to doing a lot of good. At the moment, we can't even afford cheap, so it isn't going to happen.

If wind generators are knocked out I am not clear why CCGT & even Coal Stations would be unaffected (unless they were not connected to the grid at the time.


Proofing everything might be, but there are some critical functions that need to happen.  Hospitals, water supply and sewerage (increasingly reliant on pumping rather than gravity) just for a start.

There is no reason to suspect that wind turbines would be more vulnerable than fuel burning plant. Being erected in exposed locations, wind turbines are very well protected against surges caused by lightning, this would give some protection against surges from other sources.

Anyway, the main risk is not to power production facilities but to the long transmission lines of the national grid, and the transformers and switchgear connected thereto. Power plants, whether wind powered or fuel burning are easily protected by simply disconnecting from the grid and shutting down. The switchgear used for this disconnection may be destroyed, but the power station should be safe.

Replacing significant numbers of transformers and related switchgear could take years, remembering that only very limited spares are held and production is a lengthy process. And that presumes that the factory has power, other utilities, and raw materials, and that the workforce are available and able to get to work.

Vital facilities such as hospitals should be OK in the short term as they are equipped with diesel generators. In the longer term it depends on the reliability of the generators and on a continual supply of diesel fuel which is likely to be problematic.

I don't profess to being an electrical engineer, or indeed an astrophysicist but I have been told that solar flares can also have a detrimental effect on electricity sub stations. Is this possible or should I be disabused of a pub fact?

I wonder. When I read about something like this, my first reaction is to ask for actual numbers so I can do an order-of-magnitude calculation. In this case there is a glaring absence of such numbers.

Looking around, it seems that the geomagnetic effect is a change of less than 10% of the Earth's field, which is itself not a lot in electrical engineering terms. Plugging in a few numbers such the height of a power line and its resistance per km, it is possible to estimate the worst case current that could ever flow (depending on the earthing of the line). Or almost - you really need the field change rate, or the time taken for the change of field. Well, with that nominal maximum field (less than 2000 nT), if it changed that much in 1 second (really it takes hours), my first stab at an answer is over 100 times too small to cause damage.

So I'm not convinced. The last big one - 1989 - famously led to a power cut across Quebec province. But that was because it tripped all the protection relays, so the grid lost sync and it took several hours to bring the generators back on line one by one. Nothing was damaged.

So maybe standard designs for overhead cables (of all kinds) now allow for induced voltages, and the problem's just gone away ... and nobody told the jounalists.

Thanks stuving. My reading of that is, although not an impossibility, I'd be better of excercising myself with other matters a tad more! A bit like the doomsday "black hole" Large Hadron Collider stories of old... or should I take out black hole insurance?  :)

I don't think we should be too worried or too complacent either.  The most likely damage would be to satellites which include the GPS system. Over reliance on GPS for critical functions would not be good if it comes to a coronal mass ejection.

However, in the USA NASA (https://www.nasa.gov/mission_pages/sunearth/news/flare-impacts.html) do not seem to be unduly worried about power grids.

Thankyou ellendune. I have seen Beeb documentaries highlighting this. Bad planning many years back.
Would not have happened if Brians on Tracey Island was left in charge!

Or Brains for that matter!
 :)

The degree of likely damage is largely related to the length of electric conductors affected. I would expect no significant affect on low voltage (230/400 volt) local distribution to homes etc. The 11KV network might suffer problems but would probably largely survive.
The real risk is severe damage to the high voltage grid network that supplies power in bulk for more local transformation and distribution.
Minor solar flares occur regularly, the risk comes from a severe solar storm.

..........since the railways seem unable to cope with annual seasonal temperature variations or virtually anything other than benign weather conditions, wind, leaves, ice, sunshine etc without disruption I would suggest that "massive solar events" should be someway down the list of things to worry about just for now?  ::)

According to the government's global warming advice unit (sometimes otherwise known as the BBC), it's all academic anyway as the rising tides will get us first:


http://www.bbc.co.uk/news/uk-england-devon-35146033

I have an open fire, a wind-up torch, a barbecue, and a well at my Devon home, which is over 500 feet above sea level. Don't worry about me.

This raises the possibility of India becoming the world's most "developed" country, as not only every hospital, but every office, shop and many private homes there have their own generators. In fact, in India we'd now be discussing the merits of inline vs online DGs!

My understanding is that the more important public (and private) buildings and sites all have emegency diesel driven alternators, sometimes as an UPS. They have both general and protected circuits separately wired. They have been required to do risk assessments for years, resulting in this provision. That's why I could never understand modern railway signalling centres  going down through "power failures".

Presumably the immunisation of S&T cables from nearby 25kV lines should also help with any other pulses, whether from the sun or the bomb.

The more immediate risk seems to me to be in low lying assets such as waterside substations (e.g. South Reading or Gloucester). Though Elysian in Summer, they could cause great grief in the wet through the simple lack of  c2m concrete plinths for sensitive plant. Another accountancy triumph.

OTC

Yes, most important facilities do have diesel generators and often a UPS also, presuming that such equipment actually works as intended then all should be well in the short term.
Grid power might be out for months though and I have little faith in generators working for that time, and even if the generator does work, obtaining sufficient diesel fuel could be a serious problem.

One might expect that vital signalling control equipment would have back up power supplies, yet major disruptions have resulted from entirely foreseeable local power failures.

Whenever there is solar activity over Cornwall the mechanical signalbox indicators and bells (which consist of magnetic induced needles) go absolutely haywire.  The signallers used to get very confused and started to panic when the block bells started to ring by themselves and 'line clear' got pegged on the block instruments without them touching them.......... :D ::) :P

Could that lead to right side failures in a mechanical signalbox?

Let's face it, anything that causes widespread disruption to the national grid is going to cause widespread disruption to the national everything else.

Diesel will run out quickly. The government has placed contracts for diesel generators to back up renewable energy sources, and they will probably have first dibs. We saw when there were blockades of refineries how small the stocks of fuel are in this country. (I had a LPG powered car then, so was smugly exempt from the ensuing chaos). A tanker discharges crude at the refinery, and within a fortnight it is in someone's tank - it is often fresher than your milk. As well as the limited stored supplies, and the long periods of time needed to get additional supplies from the oil fields of the middle east etc, there is the problem of ordering. There is no current method of telling the supplier that you need fuel that does not rely upon electricity somewhere along the chain. The refinery itself needs electricity to function, although some produce their own. Fuel on railways will be reserved for essential goods transport first, then passengers.

Hospitals will have an obvious priority. I understand that the Bristol Royal Infirmary has a bank of batteries to take the slack for the few seconds it takes for the back-up generators to kick in. Private vehicles will be at the bottom of the heap. Railways will have a higher priority, but not a very high one so far as pax are concerned. What is the point of travelling to your very important job in the City if you can't do it when you get there?

London will be shining bright very quickly. Cornwall less so. I'll be fine as, although I am a bit rusty, I was once reasonably good at bush-tucker, can shoot reasonably well, and know people with shotguns. The wild garlic and wild strawberry seasons re particularly exciting to me. (Other things excite me also, my business not yours. Wholesome and, so far as I am aware, legal).

Truth is, if it happens we will find out how we cope with it. If we do, which I reckon I will if nobody else does, we will learn how to deal with the next event. Even if I can't post in the GWR Coffee Shop until the fan has been cleaned.

We have a server in London, a backup in Karlsrhure and a third system we call fall back on in Fremont.   I figure if all three of those are out, people won't want our IT training nor be travelling very much by train.

Of course, there may be areas where it's kinda-hard to connect in from, and we haven't actually run any practical fail-ver tests  :-\

Yes, any severe solar storm would have a most serious effect not just on railways but on modern life in general.
A general long term lack of mains electricity would result in shortages of food, fuel, water and other supplies and cause a substantial loss of life.

I would suggest that everyone should consider keeping a reserve of food, fuel, drinking water and other supplies in case of any emergency. A severe solar storm is not IMHO a likely disaster, but consider also the risks of extreme weather, industrial disputes, riots or protests, or war in oil producing areas.

Yes. And it was quite fun (::)) being on call at the time...........

...and for those who don't know a 'Right Side Failure' is one that goes to the safe side and the signalling equipment becomes locked rather than free.

Portishead.  :P