Effect of Solar Storms on the Grid and Nuke Plants?

[Norman]

Those transformers pictured do not look small or easy to replace. I would like to know where these sorts of transformers are manufactured - especially to know if they are made domestically or would have to be ordered from abroad?

Respectfully submitted,
Steve

At the 2011 Space Weather Workshop last April a review talk was given on the power grid and it was stated in the talk that there are typically 4 transformers per station (don't know if station is the correct term here, but let's go with it). Only 3 of the transformers are required, this allows for one of them to be worked on or replaced without the 'station' going down.

But, more to your question, the speaker said that each of these huge transformers was a custom piece of equipment that took a year or longer to design and build. This lead to an estimate that a Carrington-like event would lead to portions of the US power grid to be down for 10 or more years. This was quite startling to me and my colleagues (we are involved in space weather and have zero knowledge of EE or power engineering). I will try and find the references when I find a few minutes later this evening.

EDIT: I did not even click on the link that agapemom posted, but those were some of the slides I saw in 2011. The talk was not given by Bill Murtagh, though. I believe it was given by Tom Bogden (current director of SWPC)

 

[jim hardy]

when DC passes through a transformer winding it can cause something called "saturation" which will let the current depart from a sinewave and have very sharp peaks that overheat the conductors.. it'll also cause the magnetic field to not all stay inside the transformer's iron core and that'll heat the internal structure.

a real low frequency induced current would have similar effect.

those photos showed both kinds of damage.

those conditions should be detectable.
protection schemes could be changed to detect and disconnect..
power grid would still crash but system recovery would be more graceful, days instead of years..

thanks again

 

[nikkkom]

I imagine the simplest solution is to shut down most of the grid when ultra-powerful solar flare is detected. Carrington event had ~6 hours gap between the flare and the onset of geomagnetic storm.

 

[al2207]

yes but grid operator will be reluctant to do that because of all impacts on customer and on grid . If it is planned or announce before people /industry can take necessary measure needed ; but people in general are not informed enough to understand . Keep in mind a global blackout through any country will take days upon to restoration of grid .

 

[jim hardy]

you should hear the outcry when weather bureau misses a hurricane forecast and businesses lose revenue !

first false alarm there'd be armies of tort lawyers on the utility companies.

 

[al2207]

you can foreseen what will be immense disaster from grid destruction , most running tap water is produce by treatment station , quantity of NPP will goes as Fukushima , most of cities population will be dying , we are so much dependent of electricity , it will take years to restore power and replace transformer

 

[RealWing]

Nuclear plants are designed to shutdown when they lose connection to the grid. The decay heat is not sufficient to provide the turbine-generator with appropriate power to generate electricity. Instead, plants have backup or emergency diesel generators. Some NPPs may have fossil units nearby.

Some Canadian Nucs have been uniquely designed to have the capability to continue to operate after a grid disconnection/upset. At the moment of loss of grid, they immediately "step back" to ~ 75%FP . The tubine/generator continues to supply internal power and the remaining steam energy is dumped directly into the condenser. After the 2003 blackout, 4 CANDU reactors stayed operational and were a big factor in helping get the Ontario grid back in operation.

 

[al2207]

were they located at Bruce power ?

 

[RealWing]

were they located at Bruce power ?

Three units at Bruce and one at Darlington survived the grid upset and stabilized at ~ 60% FP awaiting approval to resync with the grid.

 

[al2207]

i do not know if this was tried at point lepreau or gentilly they are Candu as well
at Gentilly GE had build back-up power with 2 or 3 jet turbine to supply NPP if needed

 

[RealWing]

i do not know if this was tried at point lepreau or gentilly they are Candu as well
at Gentilly GE had build back-up power with 2 or 3 jet turbine to supply NPP if needed

Pt Lepreau and Gentilly II both have this capability of high power condenser dump. They are a "CANDU 6" design and the same design is used in the export reactors in China, Romania, South Korea and Argentina.
Gentilly is somewhat unique in that there is a 382 MW gas turbine plant built beside it that is used for grid peaking as well as a backup power source for G2. There are 4, 82Mwe GE gas turbines there.

 

[al2207]

i had gone to both place in regard with motor control centers (Klockner Moeller )

 

[matthewdb]

Three units at Bruce and one at Darlington survived the grid upset and stabilized at ~ 60% FP awaiting approval to resync with the grid.

The CANDU design can stay in operation after a grid disconnect. They stay at high power at first to avoid problems with Xenon instability. The generator is only making enough power to meet the needs of the auxiliaries and the rest of the thermal energy is dumped into the condenser by steam bypass valves. If left disconnected for long enough they would eventually make it to 5% reactor power as the Xenon levels in the fuel dropped.

All current US plants trip the reactor on a loss of grid. The GE BWR plants could very easily be made to operate like the CANDU units but it would require extensive regulatory changes. At PWR plants there would have to be some level of modifications to the plants to let it happen.

The new plants being built in the US can continue to operate after a loss of grid (Westinghouse AP1000).

 

[jim hardy]

""All current US plants trip the reactor on a loss of grid. ""

a true enough statement in practice, though by design some of them could island.

something called "degraded grid protection" might automatically cause a plant to trip on loss of grid if not implemented thoughtfully.
or if it relies on grid for its internal power...

if the plant is supplying its own power and the control system handles the transient as described for the Candu, there's no reason my old plant couldn't "island".
Internal power was tapped right off main generator, before it went out to grid, for that reason.

 

[Caniche]

I imagine the simplest solution is to shut down most of the grid when ultra-powerful solar flare is detected. Carrington event had ~6 hours gap between the flare and the onset of geomagnetic storm.

But that would hit profits and bonuses and dividends ,risky.

 

[al2207]

yes there will be some impacts but what is consequence to do nothing ?

 

[al2207]

large CME from sun today , expected disturbance by Saturday

 

[Dotini]

It's only an M class. Here's a chart of ground current detected at Norway.
http://spaceweather.com/submissions/large_image_popup.php?image_name=Rob-Stammes-CME-jan.22-2012-b_1327226723.jpg

 

[al2207]

second punch , one more solar flare cat M8 effect S3 supposed to touch us tomorrow Jan 24

 

[Dotini]

second punch , one more solar flare cat M8 effect S3 supposed to touch us tomorrow Jan 24

Often these CME's take 2-3 days to reach us. This one has apparently accelerated to Earth in under 32 hours, a little slower than expected. The magnetosphere was compressed and satellites briefly exposed to solar wind plasma.

Respectfully submitted,
Steve

 

[al2207]

solar flare will be most destructive forces in future years
look at: ed dames predictions