You may not be have been aware of it until now, but The Automatic Earth has an in-house full-blown nuclear safety expert.
The subject of Stoneleigh's master thesis at the law faculty of Warwick University in Coventry, England, where she studied International Law in Development, was nuclear safety research.
After graduating in 1997, she became a Research Fellow at the Oxford Institute for Energy Studies, where her research field was power systems, with a specific focus on nuclear safety in Eastern Europe.
The monograph she wrote sets the nuclear safety debate in the political and economic context of the collapse of the Soviet Union. It looks at the technical aspects of nuclear safety, safety upgrade programs, safety culture and the human factor, regulation at all levels and bargaining over reactor closures.
It was published in 1999 under the title Nuclear Safety and International Governance: Russia and Eastern Europe, and it remains available online here at Oxford Institute for Energy Studies. Here's her analysis of the situation in Japan.
- Ilarg, Automatic Earth
The Japanese earthquake is a tragedy of epic proportions in so many ways. The situation continues to evolve, and the full scope of the disaster will not be understood for a long time.
One critical aspect is the effect on Japan's nuclear industry, which provides over 30% of the country's electricity from 54 reactors. Some of the largest nuclear plants in the world (Fukushima Dai-ichi and Fukushima Dai-ni, 4696 MW and 4400 MW, respectively) are located close to the epicentre, and on the coast, directly in the path of the resulting tsunami:
A state of emergency has been declared for five reactors, with the worst affected reactors being the forty year old Boiling Water Reactors (BWRs) at Fukushima Dai-ichi, 240 km north of Tokyo. These reactors shut down, as the control rods were automatically inserted to dampen the nuclear reaction (SCRAM). At least two reactors experienced a station blackout, which prevented the cooling system from functioning (a loss of coolant, or LOCA accident).
Without the ability to cool the core, the risk is a meltdown, with the potential for explosions resulting from steam or hydrogen. Even after the cessation of a nuclear chain reaction, heat from radioactive decay continues to be produced, and this heat needs to be dispersed in order to avoid a meltdown of the components of the core. Workers have been desperately trying to cool the reactor cores at units 1 and 3, but there has already been an explosion at Fukushima 1. Footage of the plant shows only the skeleton of the building remains. An evacuation zone has been expanded from 10km to 20km, and close to 200.000 people have been evacuated from the area.
Reactors are equipped with multiple cooling systems as part of the defence in depth design principle. The idea is that there should be redundant systems with no components in common, and therefore (theoretically) no possibility for common mode failures. Each system should be capable of independently preventing a design-basis accident.
Japan is a sophisticated country with a long history of nuclear power, and also a long history of seismic activity. One could argue that this is Japan's Hurricane Katrina moment, in that a predictable scenario was not adequately prepared for in advance despite the potential for very severe consequences.
Company documents show that Tokyo Electric tested the Fukushima plant to withstand a maximum seismic jolt lower than Friday's 8.9 earthquake. Tepco's last safety test of nuclear power plant Number 1—one that is currently in danger of meltdown—was done at a seismic magnitude the company considered the highest possible, but in fact turned out to be lower than Friday's quake. The information comes from the company's "Fukushima No. 1 and No. 2 Updated Safety Measures" documents written in Japanese in 2010 and 2009.
The documents were reviewed by Dow Jones. The company said in the documents that 7.9 was the highest magnitude for which they tested the safety for their No. 1 and No. 2 nuclear power plants in Fukushima. Simultaneous seismic activity along the three tectonic plates in the sea east of the plants—the epicenter of Friday's quake—wouldn't surpass 7.9, according to the company's presentation. The company based its models partly on previous seismic activity in the area, including a 7.0 earthquake in May 1938 and two simultaneous earthquakes of 7.3 and 7.5 on November 5 of the same year.
The Fukushima 1 plant was equipped with 13 diesel back-up generators to power the Emergency Core Cooling System (ECCS), but all of these failed. Battery back-ups are available, but these function only for a few hours. Without the ability to cool the reactor, the outcome is a meltdown, which can occur rapidly after the failure of cooling:
... There seems to be considerable evidence that we are closer to the beginning of this disaster than to the end, and already it is almost unprecedented in scope.
"If this accident stops right now it will already be one of the three worst accidents we have ever had at a nuclear power plant in the history of nuclear power," said Joseph Cirincione, an expert on nuclear materials and president of the U.S.-based Ploughshares Fund, a firm involved in security and peace funding.
Comparisons are being made with the accident at Chernobyl, but there are a number of very important differences, notably in terms of reactor design, and therefore accident implications. Nuclear safety in the former Soviet Union was once my research field (see Nuclear Safety and International Governance: Russia and Eastern Europe), and the specifics of the accident at Chernobyl could not be replicated in Japan. The risk in Japan is primarily meltdown, not a Chernobyl-style run-away nuclear reaction.
... Non-technical comparisons between Fukushima and Chernobyl are more apt, specifically in terms of governance in the nuclear industry and complacency as to risk. Nuclear insiders in many jurisdictions are notorious for being an unaccountable power unto themselves, and failing to release critical information publicly.
The Soviet nuclear bureaucracy ignored obvious risks and concealed accidents wherever possible. While nothing remotely like so serious has occurred previously in Japan, Fukushima 1 has been at the centre of transparency problems in the Japanese nuclear industry before. In 2002, the president and four executives of Tokyo Electric Power Corporation (TEPCO) were forced to resign over the falsification of repair records.
The company was suspected of 29 cases involving falsified repair records at nuclear reactors. It had to stop operations at five reactors, including the two damaged in the latest tremor, for safety inspections. A few years later it ran into trouble again over accusations of falsifying data.
In late 2006, the government ordered TEPCO to check past data after it reported that it had found falsification of coolant water temperatures at its Fukushima Daiichi plant in 1985 and 1988, and that the tweaked data was used in mandatory inspections at the plant, which were completed in October 2005.
In addition, the Japanese government had been repeatedly warned about seismic risks:
[..] the real embarrassment for the Japanese government is not so much the nature of the accident but the fact it was warned long ago about the risks it faced in building nuclear plants in areas of intense seismic activity. Several years ago, the seismologist Ishibashi Katsuhiko stated, specifically, that such an accident was highly likely to occur. Nuclear power plants in Japan have a "fundamental vulnerability" to major earthquakes, Katsuhiko said in 2007. The government, the power industry and the academic community had seriously underestimated the potential risks posed by major quakes.
... Many countries are currently looking to nuclear power to carry the load as energy production from conventional fossil fuels declines. Japan has previously unveiled very ambitious plans to expand nuclear capacity:
The Japan Atomic Energy Agency has modelled a 54 percent reduction in CO2 emissions from 2000 levels by 2050, leading on to a 90 percent reduction by 2100. This would lead to nuclear energy contributing about 60 percent of primary energy in 2100 (compared with 10 percent now), 10 percent from renewables (now 5 percent) and 30 percent fossil fuels (now 85 percent).
... Proponents argue that the energy returned on energy invested (EROEI) for nuclear power is sufficient to power our societies, that nuclear power can be scaled up quickly enough as fossil fuel supplies decline, that there will be sufficient uranium reserves for a massive expansion of capacity, that nuclear is the only option for reducing carbon dioxide emissions, and that nuclear power can be operated with no safety concerns through probabilistic safety assessment (PSA).
I disagree with all these assertions. Looking at the full life-cycle energy inputs for nuclear power, it seems to be barely above the minimum EROEI for maintaining society, and the costs (in both money and energy terms) are front-loaded.
Scaling up nuclear capacity takes extraordinary amounts of both money and time. While construction can be speeded up, where this has been done (as it was in Russia), the deleterious effect on construction standards was significant. Uranium reserves, especially the high-grade ores, are depleting rapidly. The reduction in carbon dioxide emissions over the full life-cycle do not impress me. In addition, nuclear authorities make risk decisions without informing the public. They have consistently made risk calculations that have grossly underestimated the potential for accidents of the kind that can have generational impacts.
In my view, nuclear power represents an unjustified faith in the power of human societies to control extremely complex technologies over the very long term. Any activity requiring a great deal of complex and cooperative control will do badly in difficult economic times.
Also, no human society has ever lasted for as long as nuclear waste must be looked after. It needs to be held in pools on site for perhaps a hundred years in order to cool down enough for permanent disposal, assuming a form of permanent disposal could be conceived of, approved and developed. During this period, the knowledge as to how this must be done will need to be maintained, and this may be more difficult than is currently supposed.
We need to evaluate the potential for a nuclear future in light of the disaster in Japan. This was not unpredictable, and should have been accounted for in any realistic assessment of nuclear potential. It cannot realistically be described as a black swan event.
Japan has few energy alternatives, as it lacks indigenous energy reserves and must import 80% of its energy requirements. It was therefore prepared to make Faustian bargains despite what should have been obvious risks. The impact of the loss of so much capacity, much of it probably permanently, on available electric power following the accident is very likely to impede Japan's ability to recover from this disaster, potentially strengthening the parallels with America's Hurricane Katrina.
We need to assess the risks inherent in using nuclear power in other locations, whether or not the risk they face is seismic (see Metsamor in Armenia, for instance, or Diablo Canyon in California). There are risks in many areas, most of which are grounded in human behaviour, either at the design stage or the operational phase. Human behaviour can easily turn what should be a one in one hundred thousand reactor-year event in to something all too likely within a human lifespan. Nuclear power may allow us to cushion the coming decline in fossil fuel availability, but only at a potentially very high price