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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.
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
I can assure you it was not for time between nuclear accidents, but don't let that little truth stop you from you from making a slant.
I never claimed it was. I designed the thing; it was pretty clear they meant industrial accident in the normal sense of someone cutting themselves, dropping a hammer on their foot, etc. Nevertheless it struck me as a strange thing to want to put on display, because no matter what value the display showed up to 999, it would either be misinterpreted (e.g. as a nuclear accident) or always look far too low. The only way it would ever be impressive would be if it had a 10-digit display that always showed some very large number (but then that would be dishonest). So what's the point of it? Not for me to question, we were happy to take the customer's money.
> 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.
"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....
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.