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Gas Cooled Reactors Shut Down In UK
mdsolar writes EDF Energy, the British subsidiary of the French state-controlled utility, said on Monday that it was shutting down three nuclear reactors and that a reactor with a fault that has been shut down since June would remain so. The facilities, which are being investigated as a precaution, generate nearly a quarter of nuclear capacity in Britain. The British Office for Nuclear Regulation said that there had been no release of radioactive material and no injuries. Industry experts did not anticipate much effect on electricity supplies or prices in the short term. EDF said that over the next few days it would idle a second reactor at the facility, Heysham 1, in northwest England. The company said it would also shut down two other reactors of similar design at Hartlepool in northeast England to investigate whether they had the same flaws.
UK gets about 18% of its power from nuclear (before this shutdown). Four new plants are planned at two sites that EDF energy owns, ground broken for those
Taking that many GW-hrs of production offline for that length of time is a serious outage.
Greater modularity would allow for a quicker ID of the scope of the problem, even if the total time to repair or replace would be greater.
Pain is merely failure leaving the body
The reactor, in fact, doesn't have a fault. There was a potential issue identified in the heat exchanger at one unit, found during a routine check, and the others have been shut down early to allow the heat exchangers at those to also be checked earlier than scheduled.
As much as mdsolar wishes it was, this is in fact a non-issue. The system and safety protocols are working precisely as they were designed.
I once designed a huge display clock for the reception area of Heysham nuclear power station. The clock had a sweep second hand that traced out a ring of LEDs once per minute, and a counter that showed the number of days since the last industrial accident. The specification called for this counter to have just three digits, which frankly didn't inspire much confidence.
There is no present, perfect way to deliver the electricity those of us on the grid have come to appreciate. When you're talking about the mainstays of the grid's backbone (coal, crude, gas, hydroelectric, nuclear), none are generated without environmental consequence.
Continue to develop the renewables, but for fuck's sake, don't take nuclear off the table based on the performance of aging plants.
Happiness in intelligent people is the rarest thing I know.
Ernest Hemingway
These are just boiler cracks - sorry the apocalypse is not going to happen. Power draw is low at this time of year so there is no real affect on national electricity resources.
Phil
http://www.antipope.org/charli...
> How does having a larger number of small reactors
He didn't say that. He said modular. As in, each turbine module should be separable from each reactor module. Within the reactor itself, you'd have separate modules that you could inspect or replace, rather than bringing the whole facility down for eight weeks. If you're looking at cooling issue, you take one cooling module down at a time rather than taking apart the whole facility.
Often, larger things are more modular, while smaller versions are built in one piece, so "more modular" certainly does not mean "smaller" or "a larger quanity of".
You're right, mdsolar seems to have submitted something that isn't outright propaganda. It IS about precautions regarding a potential flaw with the UK's reactor design, so in that sense it is "anti-nuke" and by extension "pro (md)solar", but it's largely objective and factual.
you can build and operate the hamster wheels right at home; maybe a giant one in front of Parliament or Buckhingham for Her Majesty's pleasure.
I though London already had a giant hamster wheel on the South Bank - the EDF Energy Hamster Wheel?
Socialism: a lie told by totalitarians and believed by fools.
"The reactor problems highlight that most of Britain’s nuclear installations, which generate about 20 percent of the country’s electricity, are approaching the end of their lives. The four EDF reactors under investigation were commissioned in 1983 and are officially scheduled to be removed from service in 2019. EDF Energy had been expected to seek extensions to the lives of the plants, but if the problems turn out to be too expensive to be worth fixing, then they might end up being permanently closed sooner than expected. “If this fault is as a result of the aging of the unit, this has potential implications for the operational life of these four units and, potentially, others as well,” said Antony Froggatt, a nuclear analyst at Chatham House, a London research organization."
$27 billion for Hinkley Point....
It's things like this that are the answer to the "just build a standard reactor everywhere and have an economy of scale" folks. The other answer is that since nuclear power, more than all other alternative energies, is still in a process of improvement so it makes little sense to have a fifteen year plan to build a lot of identical reactors when there could be a vast improvement in ten years.
Would be nice at the sub-unit level but take a look at a thermal power station to get some idea that the scale makes it impractical once you have enough steam to spin a turbine. Big turbines with lots of high pressure steam get the job done far better than little ones. Of course you could have something like a lot of little pebble bed reactors making steam in parallel on the boiler side making it possible to just shut down one reactor, but after the stuff is boiled it's pretty well the whole unit goes down for just about anything.
Notice that I used the word "unit". A thermal power station can be made up, for example, of eight units, with eight turbine rotors, eight boilers (nukes would include reactors at that bit) and each unit using half a cooling tower each. You can take 1/8 of the plant down without impacting on the rest and that's what's done with scheduled maintanance.
However it looks like this situation is like grounding all of a type of aircraft when a fault is found, so it's thought of being serious enough to check out all the reactors of that type at once and being worth shutting down every unit of that type. So modularity is not going to save you so long as at least one part subject to the "recall" is required by each unit.
The French had this a few times and had to shut down all of their commercial nuclear power plants at once on occasion but it's not a nuclear thing, it's the drawback of a monoculture.
Although the story link in your summary seems factually correct, the slashdot summary is qute wrong.
EDF Energy as a whole supplies 25% of the UK's energy needs (57.5 GW peak in 2012) with 16 nuclear reactors (about 9.9 GW of capicity) and 7 conventional coal and gas turbines (3,4 GW of capacity) and various renewable energy sources with about 1,5GW of capacity. Of the 16 reactors, 1 is a pressurised water reactor (PWR) and 15 are avanced gas reactors (AGR) and four of these AGRs are of the same design as Dungeness B with the faulty boiler pump. There are only 4 of those reactors offline and only 3 of which are offline for unscheduled maintenance and the other twelve are still running. Just because EDf Energy has 15 AGRs it doesn't mean that all 15 have the same boiler pumps as Dungeness B. Dungeness B has been shut down since june due to a pump failure and two other reactors were shutdown for an inspection of similar pumps. The fourth reactor currently shutdown (Heysham 1) is in a scheduled outage and Hartepool 1 pumps will be inspected in a schedue outage later this month.
You can see the current status of EDF Energies AGR reactors
http://www.edfenergy.com/energy/power-station/daily-statuses
or
http://www.edfenergy.com/energy
So the real impact of this problem is in fact only three reactors offline that should have been functional with a capicity of about 1,6 GW. As ratio of EDF energies total production capicity of 14,8 GW this is 12% of their capacity of 3% of the UKs total energy production capacity. As its summer the energy needs of the UK are in fact reduced and most scheduled outages of nuclear reactors in Europe and performed in this period are this reason, so a 3% loss of capacity in summer is frankly nothing.
D.
The plants which have been shut down are Heysham 1 and Hartlepool, which share a design. The power station at Torness is a slightly more modern design which is shared with the Heysham 2 plant.
> Big turbines with lots of high pressure steam get the job done far better than little ones. Of course you could have something like a lot of little pebble bed reactors
Modular
noun
something, as a house or piece of furniture, built or organized in self-contained units or sections.
http://dictionary.reference.co...
Modularity has nothing to do with big versus small. Think of a modular home for example, it's not made up of lots of little homes. Modular means steam from one reactor core piped to different turbines, for example, because the turbine attaches to the reactor core only at defined interface points, otherwise they are separate modules. Which means you can do maintenance on a turbine module without touching the reactor core.
I am really surprised that Britain continued to use graphite moderators in their power reactors. the Wigner effect of neutron poisoning in the moderator was very well known going into the 50s, making those reactors somewhat unpredictable. after Windscale, they should have known better.
if this is supposed to be a new economy, how come they still want my old fashioned money?
You could say the Brits have a BONR for nuclear power. Why, oh why couldn't it have been Nuclear Energy Regulation?
It's simple - consider when a type of aircraft is grounded and checjed as an example. Now apply that to a specific type of reactor or for a not necessarily nuclear example a specific model of turbine. A monoculture increases the impact of such a situation.
I suggest you read what I've written above instead of just skim until you hit a key word to get some idea why instead of getting all condescending about an issue outside of your area of awareness. I tried to clarify things without sounding like I was dumbing it down too much and being condescending so I would appreciate it if you would do the same and avoid being condescending even if your misunderstanding makes you think I don't know what your post was about. This dictionary shit is getting old.
Such levels of complexity are seen as accidents waiting to happen with MPa of steam even with enormous valves to isolate each boiler unit.
Since everything runs at around full rated capacity that means you need a spare of every portion of the process to be able to do such a thing - so an entire spare unit. Does that make sense yet? If you've got an entire spare unit then you have the capacity to shut down the one with problems anyway instead of a bit at a time.
That's why the mulitple inputs make little sense, if something's at 100% what do you do with the extra steam? You can't use it unless there's an idle turbine somewhere in your complex network.
Also your modular idea doesn't help in situations like this where everything in the plant that can make steam is being taken offline due to a potential fault in all reactors.
Is that clear enough yet?
A couple of words went missing from my post, such the sentence you quoted didn't end up meaning what I intended to say
> steam from one reactor core piped to different turbines
I did NOT intend to say that steam from one reactor should be piped to multiple turbines. As you indicate, that could well create additional, unnecessary complexity.
What I intended to say is that you should be able to replace or service the turbine module without digging into the reactor cite module, because they are connected only at limited points. If you've worked on cars much, you may have spent 30 minutes replacing a water pump on an old truck, and six hours replacing a water pump on a newer car. That's what I was talking about, but missing words garbled my message. Clear lines of separation between different modules, with well-defined connections between them, should make maintenance simpler and faster.
Sorry about the dictionary shit, but you still kept on about "lots of little reactors" being a bad idea after I stated plainly that I wasn't suggesting such a thing.