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India is producing power from solar cells more cheaply than by burning diesel for the first time, spurring billionaire Sunil Mittal and Coca-Cola Co. (KO)’s mango supplier to jettison the fuel in favor of photovoltaic panels. The cost of solar energy in India declined by 28 percent since December 2010, according to Bloomberg New Energy Finance. The cause was a 51 percent drop in panel prices last year as the world’s 10 largest manufacturers, led by China’s Suntech Power Holdings Co. (STP), doubled output capacity.

“Solar is going mainstream in India, helped by Chinese pricing,” said Ardeshir Contractor, founder of developer Kiran Energy Solar Power Pvt. Kiran, whose investors include Bessemer Venture Partners, an early financier of Skype Technologies SA, won one of the largest projects auctioned by India last month.

at the Fort Calhoun Nuclear Power Station near Blair, Nebraska, the river is already lapping at the Aqua Dams -- giant plastic tubes filled with water -- that form a stockade around the plant's buildings. The plant has become an island.

The Nuclear Regulatory Commission (NRC) issued a "yellow finding PDF" (indicating a safety significance somewhere between moderate and high) for the plant last October, after determining that the Omaha Public Power District (OPPD) "did not adequately prescribe steps to mitigate external flood conditions in the auxiliary building and intake structure" in the event of a worst-case Missouri River flood. The auxiliary building -- which surrounds the reactor building like a horseshoe flung around a stake -- is where the plant's spent-fuel pool and emergency generators are located.

OPPD has since taken corrective measures, including sealing potential floodwater-penetration points, installing emergency flood panels, and revising sandbagging procedures. It's extremely unlikely that this year's flood, no matter how historic, will turn into a worst-case scenario: That would happen only if an upstream dam were to instantaneously disintegrate. Nevertheless, in March of this year the NRC identified Fort Calhoun as one of three nuclear plants requiring the agency's highest level of oversight. In the meantime, the water continues to rise

Federal officials say two nuclear reactors at the North Anna Power Station in Louisa County, Va., were automatically taken off line by safety systems around the time of the earthquake. The Dominion-operated power plant is being run off three emergency diesel generators, which are supplying power for critical safety equipment. The NRC and Dominion are sending people to inspect the plan

A fourth diesel generator failed, but it wasn't considered an emergency because the other generators are working, according to the Nuclear Regulatory Commission. Dominion said it declared an alert at the North Anna facility and the reactors have been shut down safely and no major damage has been reported.

The earthquake was felt at the company's other Virginia nuclear power station, Surry Power Station in southeast Virginia, but not as strongly there. Both units at that power station continue to operate safely, Dominion said. The quake also caused Dominion's newest non-nuclear power station, Bear Garden in Buckingham County, to shut down automatically.

Four generators that power emergency systems at U.S. nuclear plants have failed when needed since April, an unusual cluster that has attracted the attention of federal inspectors and could prompt the industry to re-examine its maintenance plans. None of these failures has threatened the public. But the diesel generators serve the crucial function of supplying electricity to cooling systems that prevent a nuclear plant’s hot, radioactive fuel from overheating, melting and potentially releasing radiation into the environment. That worst-case scenario happened this year when the Fukushima Dai-ichi nuclear plant in Japan lost all backup power for its cooling systems after an earthquake and tsunami. Three diesel generators failed after tornadoes ripped across Alabama and knocked out electric lines serving the Tennessee Valley Authority’s Browns Ferry nuclear plant in April. Two failed because of mechanical problems and one was unavailable because of planned maintenance.

Another generator failed at the North Anna plant in Virginia following an August earthquake. Generators have not worked when needed in at least a dozen other instances since 1997 because of mechanical failures or because they were offline for maintenance, according to an Associated Press review of reports compiled by the U.S. Nuclear Regulatory Commission. “To me it’s not an alarming thing,” said Michael Golay, a professor at the Massachusetts Institute of Technology who studies risk at nuclear plants. “But if this trend were to continue, you’d certainly want to look into it.”

ATLANTA - Four generators that power emergency systems at nuclear plants have failed when needed since April, an unusual cluster that has attracted the attention of federal inspectors and could prompt the industry to re-examine its maintenance plans. None of these failures has threatened the public. But the diesel generators serve the crucial function of supplying electricity to cooling systems that prevent a nuclear plant's hot, radioactive fuel from overheating, melting and potentially releasing radiation into the environment. That worst-case scenario happened this year when the Fukushima Dai-ichi nuclear plant in Japan lost all backup power for its cooling systems after an earthquake and tsunami.

hree diesel generators failed after tornadoes ripped across Alabama and knocked out electric lines serving the Tennessee Valley Authority's Browns Ferry nuclear plant in April. Two failed because of mechanical problems and one was unavailable because of planned maintenance. Alabama nuclear plant cited for safety lapses Another generator failed at the North Anna plant in Virginia following an August earthquake. Generators have not worked when needed in at least a dozen other instances since 1997 because of mechanical failures or because they were offline for maintenance, according to an Associated Press review of reports compiled by the U.S. Nuclear Regulatory Commission.

An unstoppable tide of radioactive trash and chemical waste from Fukushima is pushing ever closer to North America. An estimated 20 million tons of smashed timber, capsized boats and industrial wreckage is more than halfway across the ocean, based on sightings off Midway by a Russian ship's crew. Safe disposal of the solid waste will be monumental task, but the greater threat lies in the invisible chemical stew mixed with sea water.

This new triple disaster floating from northeast Japan is an unprecedented nuclear, biological and chemical (NBC) contamination event. Radioactive isotopes cesium and strontium are by now in the marine food chain, moving up the bio-ladder from plankton to invertebrates like squid and then into fish like salmon and halibut. Sea animals are also exposed to the millions of tons of biological waste from pig farms and untreated sludge from tsunami-engulfed coast of Japan, transporting pathogens including the avian influenza virus, which is known to infect fish and turtles. The chemical contamination, either liquid or leached out of plastic and painted metal, will likely have the most immediate effects of harming human health and exterminating marine animals.

Many chemical compounds are volatile and can evaporate with water to form clouds, which will eventually precipitate as rainfall across Canada and the northern United States. The long-term threat extends far inland to the Rockies and beyond, affecting agriculture, rivers, reservoirs and, eventually, aquifers and well water.   Falsifying Oceanography

Dismissed as a “nobody” by Japan’s nuclear industry, seismologist Katsuhiko Ishibashi spent two decades watching his predictions of disaster come true: First in the 1995 Kobe earthquake and then at Fukushima. He says the government still doesn’t get it.The 67-year-old scientist recalled in an interview how his boss marched him to the Construction Ministry to apologize for writing a 1994 book suggesting Japan’s building codes put its cities at risk. Five months later, thousands were killed when a quake devastated Kobe city. The book, “A Seismologist Warns,” became a bestseller.That didn’t stop Haruki Madarame, now head of Japan’s Nuclear Safety Commission, from dismissing Ishibashi as an amateur when he warned of a “nuclear earthquake disaster,” a phrase the Kobe University professor coined in 1997. Ishibashi says Japan still underestimates the risk of operating reactors in a country that has about 10 percent of the world’s quakes.

“What was missing -- and is still missing -- is a recognition of the danger,” Ishibashi said, seated in a dining room stacked with books in his house in a Kobe suburb. “I understand we’re not going to shut all of the nuclear plants, but we should rank them by risk and phase out the worst.”Among Japan’s most vulnerable reactors are some of its oldest, built without the insights of modern earthquake science, Ishibashi said. It was only in the last four years that Japan Atomic Power Co. recognized an active fault line running under its reactor in Tsuruga, which opened in 1970 about 120 kilometers (75 miles) northeast of Osaka and close to a lake that supplies water to millions of people in the region.New Fault LinesJapan Atomic is reinforcing the plant to improve quake tolerance and believes it’s safe despite the discovery of new active faults lines in 2008, Masao Urakami, a Tokyo-based spokesman for the utility, said.“We can’t respond to every claim by every scientist,” he said. “Standards for seismic ground motion are not decided arbitrarily, but are based on findings by experts assigned by the government.”

Reactor 1 at the Tsuruga plant, which had its license extended for 10 years in 2009, is one of 13 on Wakasa bay, a stretch of Sea of Japan coast that is home to the world’s heaviest concentration of nuclear reactors. The area is riddled with fault lines found in the last three or four years, according to Ishibashi.

A nuclear power plant that was shut down after an earthquake struck central Virginia Tuesday had seismographs removed in 1990s due to budget cuts. U.S. nuclear officials said that the North Anna Power Station, which has two nuclear reactors, had lost offsite power and was using diesel generators to maintain cooling operations after an 5.9 earthquake hit the region.

A power loss shut down an off-site emergency response centre near the Fukushima No 1 nuclear power plant for half a day after the Great East Japan Earthquake on March 11, delaying the initial response to the nuclear disaster at the power plant, according to sources. According to the Nuclear and Industrial Safety Agency, the centre lost its external power supply immediately after the earthquake, and an emergency diesel generator stopped operating soon after. Due to the power loss, agency officials stationed at the centre were unable to use important equipment such as monitors that show conditions inside the plant. The agency, which believes the earthquake caused the generator to break down, had not taken any anti-seismic reinforcement measures to protect the generator, the agency said.

The government panel tasked with investigating the nuclear crisis has begun studying the case, according to the sources. The off-site centre is located in Okumamachi, Fukushima Prefecture, about five kilometres from the nuclear power plant.

Nuclear power plants in Pennsylvania are preparing to cope with flooding, but none has declared a state of emergency, US Nuclear Regulatory Commission spokesman Neil Sheehan said Thursday. All the Pennsylvania nuclear plants that could potentially be affected by flooding are in close communication with NRC, and with state and local officials, and the agency has resident inspectors at each plant who are monitoring the situation, Sheehan said. The plants were all operating at full power early Thursday, according to NRC data, except for Exelon Nuclear's Peach Bottom-3, which was at 88% power and has been gradually reducing its output for several days ahead of refueling outage.

Emergency diesel generators and their fuel tanks at those plants are "located at a higher elevation, in buildings designed to keep them dry," Sheehan said. Exelon Nuclear's Three Mile Island-1, located along the Susquehanna River, 10 miles southeast of Harrisburg, began its abnormal operating procedure for river flooding early Wednesday, Sheehan said. The river peaked at 291 feet above sea level Wednesday and was at 288 feet above sea level early Thursday. It is expected to crest Thursday at about 297 feet above sea level, he said.

If the river reaches 300 feet above sea level, then the plant would have to declare an unusual event, the least significant of NRC's four emergency levels, Sheehan said. If the river reaches 302 feet above sea level, the plant would need to shut and an alert, the next highest level of emergency, would need to be declared. "Important equipment" at Three Mile Island-1 is protected against flooding up to about 315 feet above sea level, Sheehan said.

The magnitude-5.8 earthquake last month in Virginia caused about twice as much ground shaking as a nearby nuclear power plant was designed to withstand, according to a preliminary federal analysis.

Parts of the North Anna Power Station in Mineral, Va., 11 miles from its epicenter, endured jolts equal to 26% of the force of gravity (0.26g) from some of the higher-frequency vibrations unleashed by the quake, said Scott Burnell, spokesman of the Nuclear Regulatory Commission.

An NRC document says the reactors' containment structure was built to withstand 12% of the force of gravity (0.12g.) Dominion, the power company that operates the plant, says parts of the plant can handle up to 0.18g.STORY: Quake readiness of nuclear power plants unclear

WASHINGTON (AP) — The risk that an earthquake would cause a severe accident at a U.S. nuclear plant is greater than previously thought, 24 times as high in one case, according to an AP analysis of preliminary government data. The nation's nuclear regulator believes a quarter of America's reactors may need modifications to make them safer.The threat came into sharp focus last week, when shaking from the largest earthquake to hit Virginia in 117 years appeared to exceed what the North Anna nuclear power plant northwest of Richmond was built to sustain.

The two North Anna reactors are among 27 in the eastern and central U.S. that a preliminary Nuclear Regulatory Commission review has said may need upgrades. That's because those plants are more likely to get hit with an earthquake larger than the one their design was based on. Just how many nuclear power plants are more vulnerable won't be determined until all operators recalculate their own seismic risk based on new assessments by geologists, something the agency plans to request later this year. The NRC on Thursday issued a draft of that request for public comment.

The review, launched well before the East Coast quake and the Japan nuclear disaster in March, marks the first complete update to seismic risk in years for the nation's 104 existing reactors, despite research showing greater hazards

The first of Fukushima Dai-ichi's six nuclear reactors came online in 1970, a full nine years before the Three-Mile Island crisis in the United States and 16 years before Chernobyl, the world's worst nuclear disaster. "The Fukushima plants were early plants, and so... more modern designs would be much more robust in their capability to deal with the situation" that Japan faced, said former US Nuclear Regulatory Commission chairman Richard Meserve. "Plants are much safer in their designs today." On March 11, a 9.0-magnitude quake rocked Fukushima, and the resulting 14-meter (46-foot) ocean wave drowned the plant, knocking out the power supply, the reactor cooling systems and back-up diesel generators.

Meserve said Fukushima's designers should have looked at historical data which showed a similar-sized tsunami hit the area in the year 869. The plant, he said, was designed to be able to accommodate a 5.7-meter tsunami. Meserve, an advisor to the UN's International Atomic Energy Agency, said plant developers in the United States always look at "what's the maximum probable event in that environment," and design accordingly. "It appears that this was not the case with regard to the Fukushima plant," he said. While its layout and design would not be considered by today's builders, Meserve stressed that Fukushima, for its day, was not seen as unsafe.

Designs have improved substantially in large part because engineers are "continuously learning from what has happened in the past and making sure that you learn from experience so that history is not repeated." Aside from advances like high-quality construction and passive safety systems that override human failures, today's designers incorporate what's known as "probabalistic risk assessment," which looks at the likelihood of events that could cause damage.

Emergency measures based on belief cooling systems couldn’t fail Kyodo An in-house report from Tokyo Electric Power Co. has concluded its emergency manual was useless for handling the nuclear crisis at the Fukushima power plant and that the widely held belief that a hydrogen explosion might have damaged the No. 2 reactor is false. The report on Sunday indicates the manual was drafted on the assumption that the emergency generators — including the diesel backups — would keep the reactors’ cooling systems running no matter what. At the Fukushima No. 1 plant, however, none of the backup generators for stricken reactors 1 through 4 survived the March 11 tsunami. End Extract

“Fortunately, due to the maintenance outage and the survival of one diesel generator, it seems that unit 5 reactor cores as well as spent fuel ponds have not suffered major fuel damage,” says the study. Though, Reactor No. 5 is mentioned again several pages later: “Total a posteriori [experienced levels] 133Xe emissions are 16.7 EBq, one third more than the a priori value [predicted levels] of 12.6 EBq (which is equal to the estimated inventory) and 2.5 times the estimated Chernobyl source term of 6.5 EBq.

If there was only 12.6 EBq of xenon-133 inventory that could be emitted from reactors 1-3 and spent fuel pool No. 4 — yet 16.7 EBq was experienced — where did the extra xenon come from, according to the study? “There is the possibility of additional releases from unit 5.” Another possibility is that recriticality has occurred in one of the reactor units. The study says the a priori emissions could have been overestimated, but discounts the notion that the initial 12.6 EBq figure so poorly underestimated the amount of xenon in Reactors 1-3 and SFP 4, “It is unlikely that the 133Xe inventories of the reactor units 1–3 were one third higher than estimated.”

ABSTRACT: ACPD – Xenon-133 and caesium-137 releases into the atmosphere from the Fukushima Dai-ichi nuclear power plant: determination of the source term, atmospheric dispersion, and deposition SOURCE: Discussion Paper See also: Report: Fukushima Reactors No. 5, 6 now in crisis — Cesium outside release points up 1,000% in recent days — Local says Hitachi engineers coming to help (VIDEO)

A plan to connect six reactors at the crippled Fukushima No. 1 nuclear power plant, which could have reduced the damage from the Great East Japan Earthquake and tsunami, never left the drawing board, according to sources. Tokyo Electric Power Co. sources said while consideration had been given in 2006 to connecting all sources of electricity at all six reactors, no decision was made because of technical problems. However, nuclear engineering experts said the work could have been implemented and added that overconfidence about the low possibility of all reactors losing all their electrical sources was likely behind the failure to proceed with the reconstruction work.

"TEPCO officials likely concluded that there was no need to spend time and money because of an overconfidence that a loss of electricity sources would never occur," said Tadahiro Katsuta, associate professor of nuclear engineering at Meiji University. "If the work had been carried out, there was the possibility that damage could have been reduced." After the March 11 tsunami hit the Fukushima No. 1 plant, the No. 1 to No. 4 reactors lost their electrical sources. The inability to properly cool the reactors led to a core meltdown and hydrogen explosions that severely damaged the reactors and spewed large amounts of radioactive materials into the atmosphere. The No. 5 and No. 6 reactors were connected in terms of electricity sources and the emergency diesel generator at the No. 6 reactor, which was the only one that continued to work, enabled cooling to continue at those two reactors.

As an emergency measure, TEPCO officials laid electrical cables between all six reactors by April 25. Because TEPCO proceeded with such work after the quake and tsunami, experts said if reconstruction work had been conducted in 2006, there was the possibility that a major accident could have even been prevented. According to former TEPCO executives, a plan was considered in 2006 to strengthen the electricity facilities at the Fukushima No. 1 plant to avoid a critical accident that might occur should all electrical sources be lost due to a natural disaster. The No. 1 to No. 4 reactors on the south side of the plant were connected by electrical cables and those four reactors could share electricity if the need arose.

The disaster at the Fukushima Daiichi nuclear plant in March released far more radiation than the Japanese government has claimed. So concludes a study1 that combines radioactivity data from across the globe to estimate the scale and fate of emissions from the shattered plant. The study also suggests that, contrary to government claims, pools used to store spent nuclear fuel played a significant part in the release of the long-lived environmental contaminant caesium-137, which could have been prevented by prompt action. The analysis has been posted online for open peer review by the journal Atmospheric Chemistry and Physics.

Andreas Stohl, an atmospheric scientist with the Norwegian Institute for Air Research in Kjeller, who led the research, believes that the analysis is the most comprehensive effort yet to understand how much radiation was released from Fukushima Daiichi. "It's a very valuable contribution," says Lars-Erik De Geer, an atmospheric modeller with the Swedish Defense Research Agency in Stockholm, who was not involved with the study. The reconstruction relies on data from dozens of radiation monitoring stations in Japan and around the world. Many are part of a global network to watch for tests of nuclear weapons that is run by the Comprehensive Nuclear-Test-Ban Treaty Organization in Vienna. The scientists added data from independent stations in Canada, Japan and Europe, and then combined those with large European and American caches of global meteorological data.

Stohl cautions that the resulting model is far from perfect. Measurements were scarce in the immediate aftermath of the Fukushima accident, and some monitoring posts were too contaminated by radioactivity to provide reliable data. More importantly, exactly what happened inside the reactors — a crucial part of understanding what they emitted — remains a mystery that may never be solved. "If you look at the estimates for Chernobyl, you still have a large uncertainty 25 years later," says Stohl. Nevertheless, the study provides a sweeping view of the accident. "They really took a global view and used all the data available," says De Geer.

Earthquakes are routinely measured by magnitude, or energy released. But the Nuclear Regulatory Commission (NRC)requires the nation's 104 nuclear reactors to withstand a predicted level of ground motion, or acceleration — something called g-force. What does that mean, magnitude-wise?

"I don't have what that translates into … unfortunately," NRC spokesman David McIntyre says. The agency released a statement Thursday to clarify its "earthquake measurements and design criteria," but it does not say what ground motion each reactor can handle. This muddiness heightens the concerns of industry critics, who have urged stricter safety rules after reactors at Japan's Fukushima Dai-ichi nuclear plant nearly melted down due to a magnitude-9.0 earthquake and tsunami on March 11.

A task force mandated by President Obama recommended in July that each U.S. plant be re-examined, given ongoing NRC research that shows the seismic risks for Eastern and Central U.S. nuclear power plants have increased. "The Virginia earthquake is now our local 911 call to stop delaying the implementation of stricter safety standards," Rep. Edward Markey, D-Mass., wrote in a letter this week to the NRC.