Tag Archives: LOCA

Superstorm Sandy Shows Nuclear Plants Who’s Boss

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Oyster Creek Nuclear Power Station as seen in drier times. (photo via wikipedia)

Once there was an ocean liner; its builders said it was unsinkable. Nature had other ideas.

On Monday evening, as Hurricane Sandy was becoming Post-Tropical Cyclone Sandy, pushing record amounts of water on to Atlantic shores from the Carolinas to Connecticut, the Nuclear Regulatory Commission issued a statement. Oyster Creek, the nation’s oldest operating nuclear reactor, was under an Alert. . . and under a good deal of water.

An Alert is the second rung on the NRC’s four-point emergency classification scale. It indicates “events are in process or have occurred which involve an actual or potential substantial degradation in the level of safety of the plant.” (By way of reference, the fourth level–a General Emergency–indicates substantial core damage and a potential loss of containment.)

As reported earlier, Oyster Creek’s coolant intake structure was surrounded by floodwaters that arrived with Sandy. Oyster Creek’s 47-year-old design requires massive amounts of external water that must be actively pumped through the plant to keep it cool. Even when the reactor is offline, as was the case on Monday, water must circulate through the spent fuel pools to keep them from overheating, risking fire and airborne radioactive contamination.

With the reactor shut down, the facility is dependant on external power to keep water circulating. But even if the grid holds up, rising waters could trigger a troubling scenario:

The water level was more than six feet above normal. At seven feet, the plant would lose the ability to cool its spent fuel pool in the normal fashion, according to Neil Sheehan, a spokesman for the Nuclear Regulatory Commission.

The plant would probably have to switch to using fire hoses to pump in extra water to make up for evaporation, Mr. Sheehan said, because it could no longer pull water out of Barnegat Bay and circulate it through a heat exchanger, to cool the water in the pool.

If hoses desperately pouring water on endangered spent fuel pools remind you of Fukushima, it should. Oyster Creek is the same model of GE boiling water reactor that failed so catastrophically in Japan.

The NRC press release (PDF) made a point–echoed in most traditional media reports–of noting that Oyster Creek’s reactor was shut down, as if to indicate that this made the situation less urgent. While not having to scram a hot reactor is usually a plus, this fact does little to lessen the potential problem here. As nuclear engineer Arnie Gundersen told Democracy Now! before the Alert was declared:

[Oyster Creek is] in a refueling outage. That means that all the nuclear fuel is not in the nuclear reactor, but it’s over in the spent fuel pool. And in that condition, there’s no backup power for the spent fuel pools. So, if Oyster Creek were to lose its offsite power—and, frankly, that’s really likely—there would be no way cool that nuclear fuel that’s in the fuel pool until they get the power reestablished. Nuclear fuel pools don’t have to be cooled by diesels per the old Nuclear Regulatory Commission regulations.

A site blackout (SBO) or a loss of coolant issue at Oyster Creek puts all of the nuclear fuel and high-level radioactive waste at risk. The plant being offline does not change that, though it does, in this case, increase the risk of an SBO.

But in the statement from the NRC, there was also another point they wanted to underscore (or one could even say “brag on”): “As of 9 p.m. EDT Monday, no plants had to shut down as a result of the storm.”

If only regulators had held on to that release just one more minute. . . .

SCRIBA, NY – On October 29 at 9 p.m., Nine Mile Point Unit 1 experienced an automatic reactor shutdown.

The shutdown was caused by an electrical grid disturbance that caused the unit’s output breakers to open. When the unit’s electrical output breakers open, there is nowhere to “push” or transmit the power and the unit is appropriately designed to shut down under these conditions.

“Our preliminary investigation identified a lighting pole in the Scriba switchyard that had fallen onto an electrical component. This is believed to have caused the grid disturbance. We continue to evaluate conditions in the switchyard,” said Jill Lyon, company spokesperson.

Nine Mile Point Nuclear Station consists of two GE boiling water reactors, one of which would be the oldest operating in the US were it not for Oyster Creek. They are located just outside Oswego, NY, on the shores of Lake Ontario. Just one week ago, Unit 1–the older reactor–declared an “unusual event” as the result of a fire in an electrical panel. Then, on Monday, the reactor scrammed because of a grid disturbance, likely caused by a lighting pole knocked over by Sandy’s high winds.

An hour and forty-five minutes later, and 250 miles southeast, another of the nation’s ancient reactors also scrammed because of an interruption in offsite power. Indian Point, the very old and very contentious nuclear facility less than an hour’s drive north of New York City, shut down because of “external grid issues.” And Superstorm Sandy has given Metropolitan New York’s grid a lot of issues.

While neither of these shutdowns is considered catastrophic, they are not as trivial as the plant operators and federal regulators would have you believe. First, emergency shutdowns–scrams–are not stress-free events, even for the most robust of reactors. As discussed here before, it is akin to slamming the breaks on a speeding locomotive. These scrams cause wear and tear aging reactors can ill afford.

Second, scrams produce pressure that usually leads to the venting of some radioactive vapor. Operators and the NRC will tell you that these releases are well within “permissible” levels–what they can’t tell you is that “permissible” is the same as “safe.”

If these plants were offline, or running at reduced power, the scrams would not have been as hard on the reactors or the environment. Hitting the breaks at 25 mph is easier on a car than slamming them while going 65. But the NRC does not have a policy of ordering shutdowns or reductions in capacity in advance of a massive storm. In fact, the NRC has no blanket protocol for these situations, period. By Monday morning, regulators agreed to dispatch extra inspectors to nuclear plants in harm’s way (and they gave them sat phones, too!), but they left it to private nuclear utility operators to decide what would be done in advance to prepare for the predicted natural disaster.

Operators and the Nuclear Regulatory Commission spokes-folks like to remind all who will listen (or, at least, all who will transcribe) that nuclear reactors are the proverbial house of bricks–a hurricane might huff and puff, but the reinforced concrete that makes up a typical containment building will not blow in. But that’s not the issue, and the NRC, at least, should know it.

Loss of power (SBOs) and loss of coolant accidents (LOCAs) are what nuclear watchdogs were warning about in advance of Sandy, and they are exactly the problems that presented themselves in New York and New Jersey when the storm hit.

The engineers of the Titanic claimed that they had built the unsinkable ship, but human error, corners cut on construction, and a big chunk of ice cast such hubris asunder. Nuclear engineers, regulators and operators love to talk of four-inch thick walls and “defense-in-depth” backup systems, but the planet is literally littered with the fallout of their folly. Nuclear power systems are too complex and too dangerous for the best of times and the best laid plans. How are they supposed to survive the worst of times and no plans at all?

For Nuclear Power This Summer, It’s Too Darn Hot

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You know that expression, “Hotter than July?” Well, this July, July was hotter than July. Depending on what part of the country you live in, it was upwards of three degrees hotter this July than the 20th Century average. Chicago, Denver, Detroit, Indianapolis and St. Louis are each “on a pace to shatter their all-time monthly heat records.” And “when the thermometer goes way up and the weather is sizzling hot,” as the Cole Porter song goes, demand for electricity goes way up, too.

During this peak period, wouldn’t it be great to know that you can depend on the expensive infrastructure your government and, frankly, you as ratepayers and taxpayers have been backstopping all these years? Yeah, that would be great. . . so would an energy source that was truly clean, safe, and too cheap to meter. Alas, to the surprise of no one (at least no one who watches this space), nuclear power, the origin of that catchy if not quite Porter-esque tripartite promise, cannot.

Take, for example, Braidwood, the nuclear facility that supplies much of Chicago with electricity:

It was so hot last week, a twin-unit nuclear plant in northeastern Illinois had to get special permission to continue operating after the temperature of the water in its cooling pond rose to 102 degrees.

It was the second such request from the plant, Braidwood, which opened 26 years ago. When it was new, the plant had permission to run as long as the temperature of its cooling water pond, a 2,500-acre lake in a former strip mine, remained below 98 degrees; in 2000 it got permission to raise the limit to 100 degrees.

The problem, said Craig Nesbit, a spokesman for Exelon, which owns the plant, is not only the hot days, but the hot nights. In normal weather, the water in the lake heats up during the day but cools down at night; lately, nighttime temperatures have been in the 90s, so the water does not cool.

But simply getting permission to suck in hotter water does not make the problem go away. When any thermoelectric plant (that includes nuclear, coal and some gas) has to use water warmer than design parameters, the cooling is less effective, and that loss of cooling potential means that plants need to dial down their output to keep from overheating and damaging core components. Exelon said it needed special dispensation to keep Braidwood running because of the increased demand for electricity during heat waves such as the one seen this July, but missing from the statement is that the very design of Braidwood means that it will run less efficiently and supply less power during hot weather.

Also missing from Exelon’s rationale is that they failed to meet one of the basic criteria for their exception:

At the Union of Concerned Scientists, a group that is generally critical of nuclear power safety, David Lochbaum, a nuclear engineer, said the commission was supposed to grant exemptions from its rules if there was no increase or only a minor increase in risk, and if the situation could not have been foreseen.

The safety argument “is likely solid and justified,’’ he wrote in an e-mail, but “it is tough to argue (rationally) that warming water conditions are unforeseen.’’ That is a predictable consequence of global warming, he said.

Quite. Lochbaum cites two instances from the hot summer of 2010–New Jersey’s Hope Creek nuclear station and Limerick in Pennsylvania each had to reduce output due to intake water that was too warm. In fact, cooling water problems at US thermoelectric generators were widespread along the Mississippi River during the hot, dry summer of 1988.

And the problem is clearly growing. Two months ago, a study published in Nature Climate Change predicted continued warming and spreading drought conditions will significantly reduce thermoelectric output in coming decades:

Higher water temperatures and reduced river flows in Europe and the United States in recent years have resulted in reduced production, or temporary shutdown, of several thermoelectric power plants, resulting in increased electricity prices and raising concerns about future energy security in a changing climate.

. . . .

[The Nature Climate Change study] projects further disruption to supply, with a likely decrease in thermoelectric power generating capacity of between 6-19% in Europe and 4-16% in the United States for the period 2031-2060, due to lack of cooling-water. The likelihood of extreme (>90%) reductions in thermoelectric power generation will, on average, increase by a factor of three.

Compared to other water use sectors (e.g. industry, agriculture, domestic use), the thermoelectric power sector is one of the largest water users in the US (at 40%) and in Europe (43% of total surface water withdrawals). While much of this water is ‘recycled’ the power plants rely on consistent volumes of water, at a particular temperature, to prevent overheating of power plants. Reduced water availability and higher water temperatures – caused by increasing ambient air temperatures associated with climate change – are therefore significant issues for electricity supply.

That study is of course considering all thermoelectric sources, not just nuclear, but the decrease in efficiency applies across the board. And, when it comes to nuclear power, as global temperatures continue to rise and water levels in rivers and lakes continue to drop, an even more disconcerting threat emerges.

When a coal plant is forced to shut down because of a lack of cool intake water, it can, in short order, basically get turned off. With no coal burning, the cooling needs of the facility quickly downgrade to zero.

A nuclear reactor, however, is never really “off.”

When a boiling water reactor or pressurized water reactor (BWR and PWR respectively, the two types that make up the total of the US commercial reactor fleet) is “shutdown” (be it in an orderly fashion or an abrupt “scram”), control rods are inserted amongst the fuel rods inside the reactor. The control rods absorb free neutrons, decreasing the number of heavy atoms getting hit and split in the fuel rods. It is that split, that fission, that provides the energy that heats the water in the reactor and produces the steam that drives the electricity-generating turbines. Generally, the more collisions, the more heat generated. An increase in heat means more steam to spin a turbine; fewer reactions means less heat, less steam and less electrical output. But it doesn’t mean no heat.

The water that drives the turbines also cools the fuel rods. It needs to circulate and somehow get cooled down when it is away from the reactor core. Even with control rods inserted, there are still reactions generating heat, and that heat needs to be extracted from the reactor or all kinds of trouble ensues–from too-high pressure breaching containment to melting the cladding on fuel rods, fires, and hydrogen explosions. This is why the term LOCA–a loss of coolant accident–is a scary one to nuclear watchdogs (and, theoretically, to nuclear regulators, too).

So, even when they are not producing electricity, nuclear reactors still need cooling. They still need a power source to make that cooling happen, and they still need a coolant, which, all across the United States and most of the rest of the world, means water.

Water that is increasingly growing too warm or too scarce. . . at least in the summer. . . you know, when it’s hot. . . and demand for electricity increases.

In fact, Braidwood is not the only US plant that has encountered problems this sultry season:

[A] spokeswoman for the Midwest Independent System Operator, which operates the regional grid, said that another plant had shut down because its water intake pipes were now above the water level of the body from which it draws its cooling water. Another is “partially curtailed.”

That spokeswoman can’t, it seems, tell us which plants she is talking about because that information “is considered competitive.” (Good to know that the Midwest Independent System Operator has its priorities straight. . . . Hey, that sounds like a hint! Anyone in the Midwest notice a nearby power plant curtailing operations?)

So, not isolated. . . and also not a surprise–not to the Nature Climate Change people this year, and not to the industry, itself. . . 17 years ago. The Electric Power Research Institute (EPRI), a non-profit group of scientists and engineers funded by the good folks who generate electricity (a group that has a noticeable overlap with the folks that own nuclear plants), released a study in 1995 that specifically warned of the threat a warming climate posed to electrical generation. The EPRI study predicted that rising levels of atmospheric carbon dioxide would make power production less efficient and more expensive, while at the same time increasing demand.

And climate predictions have only grown more dire since then.

Add to that mix one more complicating factor: when the intake water is warmer, the water expelled by the plant is warmer, too. And there are environmental protections in many areas that limit how hot that “waste” water can be. There have been instances in the past where thermoelectric plants have had to curtail production because their exhaust water exceeded allowable temperatures.

And yet, despite a myriad of potential problems and two decades of climate warnings, it is sobering to note that none of the US reactors were built to account for any of this. . . because all American nuclear reactors predate these revelations. That is not to say nuclear operators haven’t had 20 years (give or take) to plan for these exigencies, but it is to say that, by-and-large, they haven’t. (Beyond, that is, as described above, simply lobbying for higher water temperature limits. That’s a behavior all too recognizable when it comes to nuclear operators and regulators–when nuclear plants can’t meet requirements, don’t upgrade the procedures or equipment, just “upgrade” the requirements.)

But, rather than using all this knowledge to motivate a transition away from nuclear power, rather than using the time to begin decommissioning these dinosaurs, nuclear operators have instead pushed for license extensions–an additional 20 years beyond the original 40-year design. And, to date, the Nuclear Regulatory Commission has yet to reject a single extension request.

And now the nuclear industry–with the full faith and credit of the federal government–is looking to double down on this self-imposed ignorance. The “Advanced Passive” AP1000 reactors approved earlier this year for Georgia’s Plant Vogtle (and on track for South Carolina, too) may be called “advanced,” but they are still PWRs and they still require a large reserve of cool, circulating water to keep them operating and nominally safe.

The government is offering $8.3 billion of financing for the Georgia reactors at rock-bottom rates, and with very little cash up front from the plant owners. There have already been numerous concerns about the safety of the AP1000 design and the economic viability of the venture; factor in the impact of climate change, and the new Vogtle reactors are pretty much the definition of “boondoggle”–a wasteful, pointless project that gives the appearance of value while in reality delivering none. It is practically designed to fail, leaving the government (read: taxpayers and ratepayers) holding the bag.

But as a too-darn-hot July ends, that’s the woo being pitched by the nuclear industry and its government sweethearts. Rather than invest the money in technologies that actually thrive during the long, hot days of summer, rather than invest in improved efficiency and conservation programs that would both create jobs and decrease electrical demand (and carbon emissions), rather than seizing the moment, making, as it were, hay while the sun shines, it seems the US will choose to bury its head in the sand and call it shade.

Nuclear power was already understood to be dirty, dangerous and absurdly expensive, even without the pressures of climate change. Far from being the answer to growing greenhouse gas emissions, the lifecycle of nuclear power–from mining and milling to transport and disposal–has turned out to be a significant contributor to the problem. And now, the global weirding brought on by that problem has made nuclear even more precarious–more perilous and more pricy–and so an even more pernicious bet.

According to the Kinsey Report, every average man you know would prefer to play his favorite sport when the temperature is low. But when the thermometer goes way up and the weather is sizzling hot, a gob for his squab, a marine for his beauty queen, a GI for his cutie-pie–and now it turns out–the hour for nuclear power is not.

‘Cause it’s too darn hot.
It’s too. Darn. Hot.

Fukushima Nuclear Disaster “Man-Made” Reports Japanese Panel; Quake Damaged Plant Before Tsunami

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Aerial view of the Oi Nuclear Power Plant, Fukui Prefecture, Japan. (photo: Japan Ministry of Land, Infrastructure and Transport via Wikipedia)

The massive disaster at the Fukushima Daiichi nuclear facility that began with the March 11, 2011 Tohoku earthquake and tsunami could have been prevented and was likely made worse by the response of government officials and plant owners, so says a lengthy report released today by the Japanese Diet (their parliament).

The official report of The Fukushima Nuclear Accident Independent Investigation Committee [PDF] harshly criticizes the Japanese nuclear industry for avoiding safety upgrades and disaster plans that could have mitigated much of what went wrong after a massive quake struck the northeast of Japan last year. The account also includes direct evidence that Japanese regulatory agencies conspired with TEPCO (Fukushima’s owner-operator) to help them forestall improvements and evade scrutiny:

The TEPCO Fukushima Nuclear Power Plant accident was the result of collusion between the government, the regulators and TEPCO, and the lack of governance by said parties. They effectively betrayed the nation’s right to be safe from nuclear accidents.

. . . .

We found evidence that the regulatory agencies would explicitly ask about the operators’ intentions whenever a new regulation was to be implemented. For example, NISA informed the operators that they did not need to consider a possible station blackout (SBO) because the probability was small and other measures were in place. It then asked the operators to write a report that would give the appropriate rationale for why this consideration was unnecessary.

The report also pointed to Japanese cultural conventions, namely the reluctance to question authority–a common refrain in many post-Fukushima analyses.

But perhaps most damning, and most important to the future of Japan and to the future of nuclear power worldwide, is the Investigation’s finding that parts of the containment and cooling systems at Fukushima Daiichi were almost certainly damaged by the earthquake before the mammoth tsunami caused additional destruction:

We conclude that TEPCO was too quick to cite the tsunami as the cause of the nuclear accident and deny that the earthquake caused any damage.

. . . .

[I]t is impossible to limit the direct cause of the accident to the tsunami without substantive evidence. The Commission believes that this is an attempt to avoid responsibility by putting all the blame on the unexpected (the tsunami), as they wrote in their midterm report, and not on the more foreseeable earthquake.

Through our investigation, we have verified that the people involved were aware of the risk from both earthquakes and tsunami. Further, the damage to Unit 1 was caused not only by the tsunami but also by the earthquake, a conclusion made after considering the facts that: 1) the largest tremor hit after the automatic shutdown (SCRAM); 2) JNES confirmed the possibility of a small-scale LOCA (loss of coolant accident); 3) the Unit 1 operators were concerned about leakage of coolant from the valve, and 4) the safety relief valve (SR) was not operating.

Additionally, there were two causes for the loss of external power, both earthquake-related: there was no diversity or independence in the earthquake-resistant external power systems, and the Shin-Fukushima transformer station was not earthquake resistant.

As has been discussed here many times, the nuclear industry and its boosters in government like to point to the “who could have possibly imagined,” “one-two punch” scenario of quake and tsunami to both vouch for the safety of other nuclear facilities and counter any call for reexamination and upgrades of existing safety systems. Fukushima, however, has always proved the catastrophic case study that actually countered this argument–and now there is an exhaustive study to buttress the point.

First, both the quake and the tsunami were far from unpredictable. The chances of each–as well as the magnitude–were very much part of predictions made by scientists and government bureaucrats. There is documentation that Japanese regulators knew and informed their nuclear industry of these potential disasters, but then looked the other way or actively aided the cause as plant operators consistently avoided improving structures, safety systems and accident protocols.

Second, even if there had not been a tsunami, Fukushima Daiichi would have still been a disaster. While the crisis was no doubt exacerbated by the loss of the diesel generators and the influx of seawater, the evidence continues to mount that reactor containment was breached and cooling systems were damaged by the earthquake first. Further, it was the earthquake that damaged all the electrical systems and backups aside from the diesel generators, and there is no guarantee that all generators would have worked flawlessly for their projected life-spans, that the other external and internal power systems could have been restored quickly, or that enough additional portable power could have been trucked in to the facility in time to prevent further damage. In fact, much points to less than optimal resolution of all of these problems.

To repeat, there was loss of external power, loss of coolant, containment breach, and release of radiation after the quake, but before the tsunami hit the Fukushima nuclear plant.

And now for the bad news. . . .

And yet, as harsh as this new report is (and it is even more critical than was expected, which is actually saying something), on first reading, it still appears to pull a punch.

Though the failure of the nuclear reactors and their safety systems is now even further documented in this report, its focus on industry obstruction and government collusion continues in some ways to perpetuate the “culture of safety” myth. By labeling the Fukushima disaster as “Made in Japan,” “manmade” and “preventable,” the panel–as we are fond of saying here–assumes a can opener. By talking up all that government and industry did wrong in advance of March 11, 2011, by critiquing all the lies and crossed signals after the earthquake and tsunami, and by recommending new protocols and upgrades, the Japanese report fiats a best-case scenario for a technology that has consistently proven that no such perfect plan exists.

The facts were all there before 3/11/11, and all the revelations since just add to the atomic pile. Nuclear fission is a process that has to go flawlessly to consistently provide safe and economical electrical power–but the process is too complex, and relies on too many parts, too many people and too volatile a fuel for that to ever really happen. Add in the costs and hazards of uranium mining, transport, fuel milling, and waste storage, and nuclear again proves itself to be dirty, dangerous, and disgustingly expensive.

* * *

And, as if to put an exclamation point at the end of the Diet’s report (and this column), the Japanese government moved this week to restart the nuclear plant at Oi, bringing the No. 3 reactor online just hours before the release of the new Fukushima findings. The Oi facility rests on a fault line, and seismologists, nuclear experts and activists have warned that this facility is at risk much in the way Fukushima Daiichi proved to be.

Most of Japan’s reactors were taken offline following the Tohoku quake, with the last of them–the Oi plant–shut down earlier this year. In the wake of the disaster, Japan’s then-Prime Minister, Naoto Kan, suggested that it might be time for his country to turn away from nuclear power. Demonstrators across Japan seemed to agree and urged Kansai Electric Power Company and current Prime Minister Yoshihiko Noda to delay the restart of Oi. But the government seemed to be hurrying to get Oi back up, despite many questions and several technical glitches.

Noda insists the rush is because of the need for electricity during the hot summer months, but Japan managed surprisingly well last summer (when more of the country’s infrastructure was still damaged from the quake and tsunami) with better conservation and efficiency measures. Perhaps release of this new report provides a more plausible explanation for the apparent urgency.