In Japan Reactor Failings, Danger Signs for the U.S. By HIROKO TABUCHI, KEITH BRADSHER and MATTHEW L. WALD TOKYO - Emergency vents that American officials have said would prevent devastating hydrogen explosions at nuclear plants in the United States were put to the test in Japan - and failed to work, according to experts and officials with the company that operates the crippled Fukushima Daiichi plant.
The failure of the vents calls into question the safety of similar nuclear power plants in the United States and Japan. After the venting failed at the Fukushima plant, the hydrogen gas fueled explosions that spewed radioactive materials into the atmosphere, reaching levels about 10 percent of estimated emissions at Chernobyl, according to Japan's nuclear regulatory agency.
Venting was critical to relieving pressure that was building up inside several reactors after the March 11 tsunami knocked out the plant's crucial cooling systems. Without flowing water to cool the reactors' cores, they had begun to dangerously overheat.
American officials had said early on that reactors in the United States would be safe from such disasters because they were equipped with new, stronger venting systems. But Tokyo Electric Power Company, which runs the plant, now says that Fukushima Daiichi had installed the same vents years ago.
Nonsense. Nuclear reactors are the kindest, bravest, safest, most wonderful sources of power in the world, and every nuclear reactor in the world is operated by the United States Navy.
Actually, there's a third choice: A nice shiny new reactor built incorrectly. Read below. Then, amuse me by attempting to excuse Westinghouse for employing incompetent engineers.
Regulators Find Design Flaws in New Reactors By MATTHEW L. WALD WASHINGTON ? In a setback for the only model of nuclear reactor for which ground has been broken in the United States, government regulators have found additional problems with the design of its shield building, a crucial component, the chairman of the Nuclear Regulatory Commission said on Friday.
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The chairman, Gregory B. Jaczko, said that computations submitted by Westinghouse, the manufacturer of the new AP1000 reactor, about the building?s design appeared to be wrong and ?had led to more questions.? He said the company had not used a range of possible temperatures for calculating potential seismic stresses on the shield building in the event of an earthquake, for example.
Mr. Jaczko said the commission was asking Westinghouse not only to fix its calculations but also to explain why it submitted flawed information in the first place. Earlier this year the commission staff said it needed additional calculations from Westinghouse to confirm the strength of the AP1000?s shield building. The building has not been built; the analysis of its strength and safety is all computer based.
The announcement comes as the commission and the American nuclear industry are facing increased scrutiny as a result of the calamity that began after an earthquake and tsunami damaged the Fukushima Daiichi nuclear plant in Japan in March, leading to releases of radioactive material. Various critics have asked the commission to suspend licensing of new plants, the relicensing of old ones and various other activities until the implications of the Fukushima accident are clearer.
While the commission has said it will evaluate the Japanese accident methodically, it had previously said it did not anticipate that this would cause a delay in approving the AP1000. Now, however, it appears far warier that it will finish this summer.
Westinghouse countered in a statement that the ?confirmatory items? that the commission was asking for were not ?safety significant.? It noted, and the commission agreed, that the company had been the first to identify some of the problems itself. Still, the commission seems to have taken a slightly darker view.
The Southern Company has already dug the foundations and done other preliminary work for two of the AP1000 reactors adjacent to its existing reactors at Plant Vogtle near Augusta, Ga. The Energy Department has promised loan guarantees for that project provided that the Nuclear Regulatory Commission approves the design.
South Carolina Electric and Gas has broken ground for another two, 20 miles northwest of Columbia.
The commission had previously said it expected to approve the AP1000 design this summer. But on Friday a spokesman for the commission, Scott Burnell, said the decision would be delayed for a period of time that he could not specify until Westinghouse submitted a third round of revised calculations.
?They need to be doing the work correctly and completely, and we need to have confidence that that?s what they?re doing,? said one commission official, who said he was not authorized to be quoted by name. ?They have additional work they need to do, and a short time to complete it if it?s not going to have a significant impact on their schedule.?
Southern had been expecting to receive a license to construct and operate the new plant by the end of this year and to have the first reactor on line by mid-2016. On Friday, the company said it still planned to proceed. ?We have confidence the AP1000 technology,? a company spokesman, Todd Terrell, said.
In addition to the plants in Georgia and South Carolina, ground has also been broken on four AP1000 reactors in China, two at Sanmen and two at Haiyang. Westinghouse, which is owned by Toshiba, is making parts for the Chinese units in factories in the Pittsburgh area.
The AP1000 was in principle designed so it would be faster to build and safer to run than previous models. The letters stand for ?advanced passive,? with many of its safety features depending on natural forces like gravity and convective cooling rather than pumps and valves, which could be knocked out by electrical failures or floods as they were at Fukushima.
But the design involves a radical departure from those of existing nuclear plants. One change is to put a massive tank of emergency water on the roof so that no pumping is required to deliver it to an overheated reactor. Another is to build a free-standing steel shell around the reactor so that heat can travel through the metal and be passed off to surrounding air.
Existing Westinghouse reactors have a thick concrete dome with a steel liner that forms the reactor?s containment shell. In the new design, there is an air gap between the shell and the outer shield building, which is made of steel-reinforced concrete.
The commission has faced some internal dissent about the shield building, and outsiders have complained about the inner shell.
In its statement, Westinghouse said Friday that its reactor was ?one of the most studied, reviewed and analyzed nuclear power plant designs in the history of the commercial nuclear power industry.? And it said that the value of its passive features was being recognized now ?in light of recent events,? a reference to Fukushima.
Three other reactor designs are under consideration by the commission, but none of them has any prospect of being built soon. Under a reformed licensing system adopted in the 1990s, the commission is to approve a completed design before substantial work begins on reactor structures.
Beyond the AP1000, opponents of nuclear power are hoping the commission will slow down on other fronts.
?I commend Chairman Jaczko for exercising caution in light of the safety concerns that have been raised about the Westinghouse AP1000 design, and for announcing plans to fully examine outstanding issues regarding structural integrity and resiliency before approving the design,? said Representative Edward J. Markey, Democrat of Massachusetts and a longtime Congressional critic of the industry.
He added, ?In the wake of the Fukushima meltdown, the N.R.C. also should suspend all of its licensing decisions on new designs, new reactors or relicense applications until it incorporates the lessons of the Japanese catastrophe.?
They need more power at YOUR HOUSE, should they build a nuke plant, or a coal-fired plant? (Assume for the sake of simplicity, more for your sake than mine, that they can actually build a plant right...)
They need more power at MY HOUSE, and I don't care that it is nuke or coal, I only care that they haven't built it because of environmental whackos that think a rat will pack up and leave, so they can't build one or the other.
But the defective design can be fixed. Environmental concerns cannot. No matter which type of plant is built, there are environmental concerns. If we can't build one, then we select another that somebody else does not like. I can name environmental reasons for ANY kind of power plant that somebody might want to build.
Wind farms -- the blades kill birds that migrate through the fields. Solar farms -- tortoise populations will be forced to live in the shade. Coal -- smoke. Nukes -- what to do with the waste. They are looking at wave generation that the complaint is that the fish will be bothered. Of these examples, ONLY nukes and coal plants actually work on a footprint that does not take space equal to the size of Rhode Island to produce enough energy to support the homes that fit on the same space, not to mention the industrial needs that will still need to be supported.
You have to make up your mind that you want one kind of plant or the other, then set about to design the best that can be designed. So, I ask AGAIN, what scheme is most acceptable to YOU? Do you prefer coal-fired or nuke plants?
I live within 30 miles of San Onofre, a nuke plant that has been in operation for 40 years -- almost 50 years. I can't count the number or earthquakes that have happened during the last half century around here.
The approach I want to nuclear plant construction is one where the designers are held strictly accountable for flaws BEFORE they begin construction. Once construction begins, the design's been bought and paid for, and I mean that in the criminal sense. The NRC has been a puppet of the industry it's supposed to regulate for way too long.
Exactly, as long as they're built to withstand problems which nobody could predict 6 months ago. I'm sure you agree that things have suddenly changed, not in insurmountable ways, but in ways which absolutely must be managed honestly.
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