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Temperatures can fall by up to 4C downwind of farms

Tory MPs write to PM demanding dramatic subsidy cuts

The team from the University of Illinois found that daytime temperatures around wind farms can fall by as much as 4C, while at night temperatures can increase

Editor's Note: This is part of the IEEE Spectrum special report: Fukushima and the Future of Nuclear Power.

This past April, when the Japanese government and Tokyo Electric Power Co. (TEPCO) jointly unveiled their plan to bring the damaged reactors of the Fukushima Dai-ichi nuclear power plant to a cold shutdown and gain control of the release of radioactive materials, they set a tentative completion date for mid-January 2012. And "tentative" had to be the operative word, for the obstacles TEPCO faced—and to some extent still does face—are challenging in the extreme. They include:

Fuel rod meltdowns in reactors 1, 2, and 3 due to loss of cooling systems following the 11 March earthquake and tsunami; Severe damage to the upper levels of reactor buildings 1, 3, and 4 and slight damage to building 2, stemming from hydrogen explosions; High levels of radiation and contaminated rubble, making working conditions hazardous and difficult; Thousands of metric tons of contaminated water accumulating on the site and leaking out of the reactors.

All three damaged reactors at Japan's crippled Fukushima Daiichi nuclear power plant are below the boiling point, paving the way to bring them to a state of cold shutdown by the end of the year, the operator of the complex said on Wednesday. After a devastating earthquake and tsunami in March knocked out cooling systems and caused meltdowns of nuclear fuel rods at three of the plant's six reactors, Tokyo Electric Power (Tepco) has been trying to cool them and bring temperatures below the boiling point.

Temperatures at two of the three reactors had already dropped below 100 degrees Celsius in July and early September, leaving just one reactor above boiling point. But temperatures at the last of the three reactors fell to 99.4 degrees on Wednesday, according to Tepco spokesman Takeo Iwamoto. "The temperature has been moving up and down but it is on a steady decline," Iwamoto told Reuters. "We have cleared the temperature issue and taken a step forward towards achieving cold shutdown by the end of this year."

Plant Status After a 6.2 magnitude earthquake struck offshore from Fukushima in the early hours of July 25, Tokyo Electric Power Co. reported there were no problems with any of the systems used to stabilize the reactors at Fukushima Daiichi and no injuries. TEPCO checked the systems for water and nitrogen injection into reactors 1, 2 and 3, the water treatment facility, and the used fuel pool cooling systems for reactors 2 and 3. The Japan Atomic Industry Forum said temperatures at the bottom of Fukushima Daiichi reactor 1 have remained below 100 degrees Celsius (212 Fahrenheit) for six consecutive days through July 24. TEPCO says it achieved the lowered temperature by raising the amount of water injected into the reactor. The company has begun implementing step 2 of its recovery plan for the reactors, which includes maintaining temperatures at the bottom of reactors 1, 2 and 3 below 100 degrees Celsius. The stable operation of the circulatory water injection system is crucial to achieving that goal. TEPCO said a faulty circuit breaker was the cause of a five-hour loss of electrical power to reactors 3 and 4 July 22. Power for contaminated water treatment and for the reactors’ used fuel pool cooling was eventually restored via an alternate source. TEPCO says there was no major increase in the temperature of the pools

The company is working to improve switching systems among external power supplies. Industry/Regulatory/Political Issues A July 28 public Nuclear Regulatory Commission meeting will focus on the agency’s near-term task force recommendations for safety enhancements at U.S. nuclear energy facilities after the Fukushima accident. International Atomic Energy Agency Director General Yukiya Amano today toured the Fukushima Daiichi site, where he met with TEPCO personnel and gave an interview on location describing his visit. Amano is to meet Japanese Prime Minister Naoto Kan and government ministers to discuss the outcomes of the June IAEA ministerial conference on nuclear safety. The Nuclear and Industrial Safety Agency said it will take months to complete the first of two-stage “stress tests” it has ordered all Japanese nuclear power reactor operators to conduct before shutdown reactors can restart. NISA said it does not anticipate any of the 22 reactors that were halted for regular safety checks to resume operations this summer. The tests involve computer simulations of the reactors’ responses to emergencies such as earthquakes, tsunamis and loss of off-site power.

As TEPCO moves into the second stage of its recovery plan at Fukushima, the joint office it operates with the Japanese government to conduct and review its activities will be restructured. A new radiation and health management team will be established, and two other teams will be incorporated into a “medium-to-long term countermeasures” team. Media Highlights The New York Times editorialized on July 24 on the U.S. response to the Fukushima Daiichi accident. The opinion piece discussed steps taken by the nuclear energy industry and recommendations made by the NRC’s Fukushima-focused task force. Upcoming Events NEI will brief financial analysts in New [...] ...read more

You’ve likely heard this argument before: “The wind doesn’t always blow and the sun doesn’t always shine, so we can’t rely on renewable energy.” However, a series of recent events undermine the false dichotomy that renewable energies are unreliable and that coal, nuclear and natural gas are reliable.

There are too many reasons to list in a single blogpost why depending on fossil and nuclear energies is dangerous, but one emerging trend is that coal, natural gas and even nuclear energy are not as reliable as they are touted to be. Take for instance the nuclear disaster still unfolding in Japan. On March 11, that country experienced a massive earthquake and the resulting tsunami knocked out several nuclear reactors on the coast. Three days later, an operator of a nearby wind farm in Japan restarted its turbines - turbines that were intentionally turned off  immediately after the earthquake. Several countries, including France and Germany, are now considering complete phase-outs of nuclear energy in favor of offshore wind energy in the aftermath of the Japanese disaster. Even China has suspended its nuclear reactor plans while more offshore wind farms are being planned off that country’s coast.

In another example much closer to home, here in the Southeast, some of TVA’s nuclear fleet is operating at lower levels due to extreme temperatures. When the water temperatures in the Tennessee River reach more than 90 degrees, the TVA Browns Ferry nuclear reactors cannot discharge the already-heated power plant water into the river. If water temperatures become too high in a natural body of water, like a river, the ecosystem can be damaged and fish kills may occur. This problem isn’t limited to nuclear power plants either.

Achieving a "cold shutdown" of a nuclear reactor is not difficult as long as the reactor is not broken. A cold shutdown is defined by experts as a situation in which nuclear reactors whose operations are suspended are being stably cooled down and the temperatures in them are kept below 100 degrees Celsius. However, it is no easy task to achieve a cold shutdown at the tsunami-hit Fukushima No. 1 Nuclear Power Plant where fuel has melted and holes have developed in damaged reactors.

Goshi Hosono, state minister for the prevention of nuclear accidents, told the International Atomic Energy Agency (IAEA) annual general meeting under way in Vienna that Tokyo will do its best to achieve a cold shutdown of the stricken reactors at the plant by the end of this year. His remark suggests that the government intends to bring forward its target of achieving a stable cool-down of the troubled reactors and of substantially reducing the amount of radioactive substances released from the plant by January 2012.

The temperature at the bottom of the No. 1 reactor's pressure vessel has been stabilized at less than 100 degrees Celsius, and that of the No. 3 reactor has recently been kept below that level. Hosono appears to have made the remark at the IAEA conference while keeping in mind these positive signs. It is a matter of course for the government to try its utmost to bring the crippled reactors under control as soon as possible, and it is important for it to show its determination to achieve this goal to the international community.

and Yomiuri Shinbun has this extremely hopeful diagram that they came up with to celebrate the occasion. It shows part of the melted fuel inside the shroud of the Reactor Pressure Vessel and part of it at the bottom of the RPV, both cooled below 100 degrees Celsius inside the RPV, supposedly.

TEPCO announced on September 28 that the temperature at the bottom of the reactor of Reactor 2 at Fukushima I Nuclear Power Plant was 99.4 degrees Celsius as of 5PM on September 28. It was the first time since the March 11 accident that the temperature there dropped below 100 degrees Celsius.

Now one of the two conditions for the stable "cold shutdown", "temperature below 100 degrees Celsius", has been achieved.The other condition is to suppress the release of radioactive materials. Then the national government will make a declaration that the Fukushima accident is over, residents will return home, and we can all forget about the accident ever happened.The red dot on the bottom right of the RPV indicates the location where TEPCO has been measuring the temperature.Never mind that the basement of Reactor 2 is flooded with highly contaminated water. Needless to say, the RPV leaks, and the Containment Vessel (drywell) leaks. And we know that the suppression chamber leaks after it exploded in March 15.

This year’s World Energy Outlook report has been published by the International Energy Agency, and says wealthy and industrializing countries are stuck on policies that threaten to lock in “an insecure, inefficient and high-carbon energy system.”You can read worldwide coverage of the report here. Fiona Harvey of the Guardian has a piece on the report that focuses on the inexorable trajectories for carbon dioxide, driven by soaring energy demand in Asia.A variety of graphs and slides can be reviewed here:

According to the report, Russia will long remain the world’s leading producer of natural gas, but exploitation of shale deposits in the United States, and increasingly in China, will greatly boost production in those countries (which will be in second and third place for gas production in 2035).Last month, in an interview with James Kanter of The Times and International Herald Tribune, the new head of the energy agency, Maria van der Hoeven, discussed one point made in the report today — that concerns raised by the damage to the Fukushima Daiichi power plant could continue to dampen expansion of nuclear power and add to the challenge of avoiding a big accumulation of carbon dioxide, saying: “Such a reduction would certainly make it more difficult for the world to meet the goal of stabilizing the rise in temperature to 2 degrees Centigrade.”

Here’s the summary of the main points, released today by the agency: “Growth, prosperity and rising population will inevitably push up energy needs over the coming decades. But we cannot continue to rely on insecure and environmentally unsustainable uses of energy,” said IEA Executive Director Maria van der Hoeven. “Governments need to introduce stronger measures to drive investment in efficient and low-carbon technologies. The Fukushima nuclear accident, the turmoil in parts of the Middle East and North Africa and a sharp rebound in energy demand in 2010 which pushed CO2 emissions to a record high, highlight the urgency and the scale of the challenge.”

For the first time, record-breaking water temperatures in Long Island Sound have forced the shutdown of the Unit 2 nuclear reactor at the Millstone Power Station.

It appears to be the only nuclear power plant in the nation forced to shut down this summer due to high water temperatures, said Neil Sheehan, spokesman for the Nuclear Regulatory Commission. This is the first time Unit 2 has been shut due to high water temperature since it began operations in 1975, according to Ken Holt, spokesman for Millstone owner Dominion.

The temperature in a reactor at the crippled Fukushima No. 1 nuclear plant may have risen to 82 degrees on Feb. 12, a situation that could force the government to revoke the declaration of “an equivalent of cold shutdown.”

TEPCO said that it does not know why the temperature is rising.

High radiation levels in the No. 2 reactor are preventing workers from entering and examining the state of melted nuclear fuel.

Berkeley Lab scientists and their colleagues have discovered a new relation among electric and magnetic fields and differences in temperature, which may lead to more efficient thermoelectric devices that convert heat into electricity or electricity into heat.

An n-type semiconductor on top of a p-type semiconductor creates a vertical electric field (E, green arrow), while diffusion creates a depletion layer near the junction (orange), where the electric field is strongest. Heating one end of the device creates a heat gradient at right angles to the electric field (del T, red arrow). Electrons and holes moving in these fields are forced into loops of current, and a magnetic field is generated “sideways” (B, blue arrow), at right angles to both electric and thermal fields.

"In the search for new sources of energy, thermopower -- the ability to convert temperature differences directly into electricity without wasteful intervening steps -- is tremendously promising," says Junqiao Wu of Berkeley Lab's Materials Sciences Division (MSD), who led the research team. Wu is also a professor of materials science and engineering at the University of California at Berkeley. "But the new effect we've discovered has been overlooked by the thermopower community, and can greatly affect the efficiency of thermopower and other devices."

Here, based simplified, are the chemical reactions in the atmosphere, which explain how the Fukushima disaster impacted the Arctic ozone hole.   The cold winter in 2010-2011 produced dense stratospheric clouds over the Arctic, which due to the presence of water promoted chemical reactions with various gases to produce compounds that deplete ozone over the Arctic Circle.   The Arctic ozone hole, that began expanding due to the clouds, radically widened in March and April, coinciding with the Fukushima disaster.

"Our results show that Arctic ozone holes are possible even with temperatures much milder than those in the Antarctic," it also said.   It is harder for ozone-destroying chlorine monoxide to form in the stratosphere of the Arctic as winter temperatures are higher than in the Antarctic, according to the group.   But the depletion of the ozone layer over the Arctic appears to have progressed greatly this winter to spring because unusually cold temperatures from December through the end of March enhanced ozone-destroying forms of chlorine.   "The 2010-11 Arctic winter-spring was characterized by an anomalously strong stratospheric polar vortex and an atypically long continuously cold period," the team said in the article contributed to Nature.

From the Mainichi newspaper...   Researchers Report Unprecedented Ozone Loss In Arctic   10-3-11   TSUKUBA, Japan (Kyodo) -- The depletion of the Arctic ozone layer reached an unprecedented level in early 2011 and was "comparable to that in the Antarctic," an international research team said Sunday in the online version of the British science magazine Nature.   "For the first time, sufficient loss occurred to reasonably be described as an Arctic ozone hole," said the nine-country team, including Hideaki Nakajima of the National Institute for Environmental Studies in Tsukuba in Ibaraki Prefecture.

Nuclear reactors are operated by fallible human beings, and at least two meltdowns have been caused by poor human decisions: the 1961 meltdown of an experimental military reactor in Idaho, which killed three operators when one of them withdrew a control rod six times as far as he was supposed to (carrying out a high-tech murder-suicide over a love triangle, according to some accounts), and the Chernobyl accident, which was caused by an ill-conceived experiment conducted outside approved protocols.

So, if nuclear safety is a matter of human behavior as well as sound technical infrastructure, we should look to the social sciences in addition to engineering to improve reactor safety. After all, the machines don't run themselves. The social sciences have five lessons for us here: The blind spot. In what we might call the frog-in-boiling-water syndrome, human cognition is such that, in the absence of a disaster, individuals often filter out accumulating indications of safety problems that look like obvious red flags in retrospect -- just as frogs do not jump out of a pot of water on a stove as long as the temperature goes up slowly. Diane Vaughan's award-winning book on the Challenger disaster demonstrates a clear pattern in earlier space shuttle launches of O-ring performance degrading in proportion to declining launch temperatures -- the problem that would ultimately kill Challenger's ill-fated crew. Some shuttle engineers had become concerned about this, but the organizational complex responsible for the space shuttle could not bring this problem into full cognitive focus as long as the missions were successful. Operational success created a blinding glow that made this safety issue hard to see.

The whistle-blower's dilemma. The space shuttle program provides another example of human fallibility, explored in William Langewische's account of the Columbia space shuttle accident: Large, technical organizations tend to be unfriendly to employees who harp on safety issues. The NASA engineers who warned senior management -- correctly, as it turned out -- that the Columbia shuttle was endangered by the foam it lost on takeoff were treated as pests. (The same is true of Roger Boisjoly, the Morton Thiokol engineer who was ostracized and punished for having warned correctly that the Challenger shuttle was likely to explode if launched at low temperature.) Large technical organizations prioritize meeting deadlines and fulfilling production targets, and their internal reward structures tend to reflect these priorities. This is especially true if the organizations operate in a market environment where revenue streams are at stake. In such organizations, bonuses tend not to go to those who cause the organization to miss targets and deadlines or spend extra money to prevent accidents that may seem hypothetical. It is not the safety engineers, after all, who become CEOs. Those with safety concerns report that they often censor themselves unless they are deeply convinced of the urgency of their cause. Indeed, there is -- sadly -- substantial literature on the various forms of mistreatment of engineers who do come forward with such concerns.

Ever since the nuclear crisis erupted six months ago, the public has been clamoring to know when the damaged reactors at the Fu ku shi ma No. 1 power plant will be brought under control and when the nightmare will end. The government and Tokyo Electric Power Co., which runs the crippled plant, are working to bring the three reactors into cold shutdown by mid-January.

Cold shutdown means the temperature at the bottom of the pressure vessel, which holds the core, has been lowered to less than 100 degrees. This critical milestone, known as "Step 2" in Tepco's road map for containing the crisis, would limit the release of radioactive materials from the plant to less than 1 millisievert per year, a level that poses no health risks.

Since work at the plant is proceeding relatively smoothly, it appears likely the mid-January target will be met. But Fukushima No. 1 will still have a long way to go before the flooded plant's reactors are stable enough to be considered safe, experts warn. The main reason is the abundance of highly radioactive water.

Some of the temperature gauges for the Reactor 2 Suppression Chamber and the Containment Vessel seem to be malfunctioning.In each case, only one gauge out of several seems to be affected. Cause unknown, according to TEPCO. Countermeasures: closer monitoring of gauges.