The two nuclear plants
The Brunsbüttel (771 MW netto) and Krümmel (1345 MW netto) plants are two of the three nuclear plants operating near Hamburg, since 2000 Swedish energy giant Vattenfall owns the first and has a 50% share in the second. Both are single-block boiling water reactors (BWR), active since 1977 resp. 1984, tabled for decommissioning in 2009 resp. 2016. Krümmel is the world's most powerful BWR since an upgrade in 2005-6 -- but only nominally, the extra heat in the cooling water release was too much for the river Elbe, so it often runs at 80% power.
Already in the nineties, both plants have featured strongly in criticisms of the German nuclear industry, especially for information politics.
Brunsbüttel's operation was plagued by many accidents and faulty subsystems from the start, it even had a three-year shut-down. But the accident that drew most attention was a hydrogen explosion in 2001.
The explosion was in a pipe on top of the reactor's pressurized tank, led to a cooling water loss, worse could only be averted by closing a still intact valve. What really got critics going however was that the details only came to light thanks to leaks to the media, while the operator classified it as a non-reportable "spontaneous leakage"(!) in a non-critical part(!), and continued operation without an investigation. They chose to act so despite automatic monitoring of the systems by the government authority, who forced an investigation two months after the fact. The investigation revealed not only the cause and the seriousness (potential for meltdown), but that the collection of hydrogen gas was missing from the safety evaluations.
Krümmel is at the centre of a leukemia cluster (50 times above background level) that emerged in 1989, leading to an on-going long controversy. There is material evidence: radioactive material found on the rivershore, but its source is debated, it may also be from a nearby nuclear research facility. Krümmel had many problems with the fuel rod handling system, pumps, and a leak of the primary circle was discovered only after years.
The last minor scandal was after the accident in Forsmark nuclear plant in Sweden (also see askod's update). In that accident, an electrical failure also shut down two emergency generators that are supposed to keep cooling water circulating during power-off.
Operators in Germany, including Vattenfall, claimed that accidents of the Forsmark type aren't possible in their plants due to different technology. However, after a week, they have been forced to admit that indeed that type of accident is possible in multiple plants, and Brunsbüttel's system is even worse than Forsmark's was. Still, at first Vattenfall claimed it's no problem, only to announce later the addition of extra/replacement emergency generators.
The current failures
On 28 June 2007, both plants were shut down due to major accidents. Information about both accidents was handled scandalously.
In the Brunsbüttel plant, after repairs, a switcher short-circuited for still unknown reasons, forcing a power-down. Then during power-up two days later, the water purifying system blocked; according to Vattenfall, due to improper operation by staff. The new accidents don't seem to have been serious, however, when the oversight authority asked about what happened (these incidents were of the kind whose reporting is obligatory), the operator first denied everything, admission came only with five days delay on 6 July. The oversight authority says that hydrogen collected in the reactor water level measuring system (remember what happened in 2001).
In the Krümmel plant, one hour forty minutes after the Brunsbüttel emergency shutdown, a transformer caught fire, a fire that couldn't be estinguished for three days. The reactor was affected, too: smoke intruded the operation room and people had to work in gas masks, two safety valves opened and one pump shut down, which was enough to cause a rapid fall of water level and pressure in the core, only stopped by the activation of a second safety system.
But for the public, the operator and the oversight authority first only told that the fire didn't reach the reactor core. The authority was forced to detail the less direct consequences days later. Vattenfall manager Bruno Thomauske had the audacity to claim that they only failed to inform the public because they "misjudged the level of public interest" in the case, after "lack of media attention" for a 2005 shutdown...
According to the preliminary investigation of the Krümmel incident, presented by Thomauske also on 6 July, the Krümmel transformer fire was probably caused by the Brunsbüttel shutdown. A series of human errors during the shutdown process were also admitted, and also the loss of important data in the control computers (hmmm khm). The plant remains shut down during the summer.
The top overseeing official, Schleswig-Holstein state social minister Gitta Trauernicht (SPD), was on one hand under pressure in the Krümmel case, on the other hand, outraged when learning of Vattenfall's stonewalling in the Brunsbüttel case, which got her on Sunday to publicly threaten the withdrawal of Vattenfall's operating permit.
It is no wonder that according to the latest poll by Forsa, made before 6 July, 31% want to accelerate the nuclear phaseout (24% want to continue it as planned, 18% want to slow it down, just 22% want to turn the decision around).
Intermission: electricity generation and flows in Germany
Take a close look at the changes in five years (based on the electricity supply & use and production according to generating modes tables of the German Ministry of Economics):
Note: (a) use of oil-fired power plants is usually for balancing and fluctuates, (2) the figures for photovoltaic are surplus electricity fed into the grid, i.e. excluding unmetered own use from roof-mounted solar cells.
- First observation: the combined growth in the four renewables listed adds up exactly to the growth in consuption.
- Second observation: growth in gas, the only of the four big traditional modes to grow, is almost as much as growth in net exports.
It is also useful to show the exports/imports in detail:
It is a common spin to concentrate only on the flows across the Franco-German border, and claim Germany needs cheap French nuclear energy import. In truth, that big inflow only transits Germany en route to the Netherlands and (via Austria & Switzerland) Italy, while Germany had moderate net export most years in the nineties -- and then that grew significantly in this decade.
Power generation in (West) Germany used to be the job of large private companies with regional monopoly, and to a large extent they still rule the market the same way post-liberalisation. The most significant breach on their power was the feed-in law, which obligates grid owners to purchase from renewable producers at fixed above-market prices. These renewables are distributed power, which also means distributed ownership, thus a loss of market share would be inevitable for the majors. But, notwithstanting some naive views of market mechanisms on the pro-renewables side, the majors of course try to keep power (in both senses). So it comes that the practical result is that instead of closing older power plants, they run them for export.
In (West and later unified) Germany, for historical reasons, there are marked political connections according to generating mode. The big picture is: SPD (Social Democrats) for coal, CDU (Christian Democrats) for nuclear, Greens for renewables. The detailed picture is more complex, with pro-gas and pro-wind regional leaders of SPD, and pro-brown-coal regional CDU leaders (there was a big tussle over brown vs. black coal recently).
I note that current chancellor Angela Merkel is also close to nuclear power. She used to be a physicist, first came into Helmut Kohl's conservative government to oversee R&D, and was then environment minister. It was during the latter time that the big scandal of nuclear waste transport containers (named Castor) blew, e.g. that contamination was found on their outside with radiation levels that were orders of magnitude above the limit (up to 3000 times). In the run-up to the scandal, Merkel rejected all doubts. once it blew big, she made a stand against the companies, acting all outraged. A cunning and cynical move foreshadowing a great tactician: wasn't it her ministry, as oversight authority, that should have caught this at home, or pressed the French authorities for better information flow?
So back to the present, there are some cynical games played in the current Grand Coalition federal government.
Environment minister Sigmar Gabriel, SPD, wants to allow the construction of dozens of new-generation coal plants, ostly black coal, claiming both the 'need' to replace old units and the 'need' to replace nuclear, and arguing that their higher efficiency can result in no overall growth of emissions.
Economy minister Michael Glos, of the Bavarian CSU, and some CDU leaders have repeatedly called for either an extension of running times or an end to the end of nuclear power altogether, arguing with climate change.
Both choices would fix the market for 40 years (long amortisation times).
The latest overture in this game were claims that planned greenhouse gas cuts can't be achieved without nuclear, based on a government-sponsored study. Jérôme reported it in Will the next German election be a referendum on nuclear energy?, via Germany to stay nuclear in Merkel U-turn | International News | News | Telegraph:
Mrs Merkel's dramatic change of heart surfaced at an energy summit attended by government and industry heads in Berlin last week...
A government-commissioned study unveiled at the summit showed that Mrs Merkel's targets were not feasible without nuclear power.
...Under Germany's recent European Presidency, Mrs Merkel set the target of a 20 per cent reduction of CO2 emissions within the EU by 2020. For Germany, she has set a 40 per cent target.
The new study showed that Germany would need to maintain its use of nuclear power if it was to hit those targets.
Spin, spin, spin, and sloppy journalism.
Actually, this study said something else completely, it was released already in May, and the energy summit ended without any changes to policy (though Merkel said that the feasibility of reaching the goals shall be reviewed with the industry annually from 2010). With the row over Krümmel and Brunsbüttel (and now the latest scandalous taboo-breaking by an interior minister demanding targeted assassinations), discussion of the study went completely under, but I will talk about it.
The study was prepared by the Prognos Institute and Cologne University's Energy Economy Institute (Germany shorthand: ewi). They calculated CO2 emissions and costs in 2020 for three scenarios. What the study actually claimed was that replacing nuclear and reducing CO2 40%, by using renewables and increased efficiency, is possible, but keeping the existing nuclear plants would be cheaper (by 4.5 billion) and get a bit further (current policies: 39% reduction, extra renewables push: 41% reduction, keeping the 17 nuclear plants: 45% reduction).
If that's not enough, when that study was released early in early May, it was instantly criticised for being behind the times in its assumptions, for example calculating with constant gas prices and crude oil price stabilising at $65/barrel. One also wonders how the nuclear cost estimate holds up if aging plants are run like Brunsbüttel.
I stress again that the ability of renewables do deliver the needed capacity wasn't really called into doubt. In fact on the energy summit, the naysayers focused their ire on energy efficiency goals.
To bolster the case for renewables potential, I add that according to another study from last October, prepared by renewable energy experts under the leadership of Dr. Hermann Scheer (president of EUROSOLAR, EARE and WCRE) and the participation of Prof. Klaus Traube (who used to work on the design of the German fast-breeder prototype but 'changed sides'), a renewables growth that exceeds the needed replacement of nuclear generating capacity is possible even without a further push to increase the installation rate. Here is their projection of un-boosted growth in renewables production, overlaid on nuclear production according to the planned phaseout:
Some general words
On the narrower issue of the safety of nuclear reactors, I note again that a lot of failures are of types the safety evaluators haven't thought of, making risk calculations of questionable value. In a system as complex and integrated as a nuclear plant, such failures can become cascading failures, and part of these cascades was again not foreseen by the safety evaluators.
A new angle to human error discussed in the German media concerns aged plants: currently the second generation of operators are taking over, people who don't know the nifty details and special troubles of the plants.
Beyond health safety, there is also supply security, and the quick shutdown of two gigawatts is a major thing, demanding significant short-order balancing capacity.
Regarding secrecy and stonewalling accident investigations, what I have to wonder about is how exactly Germany is special: are there really more accidents and fudge, or are companies more stupid in their media relations, or are companies under more vigorous public scrunity?