Tuesday, January 31, 2012

Unusual Event' at Exelon's Byron nuclear plant is over

By Brian Leaf
Posted Jan 31, 2012 @ 10:03 PM



BYRON — Operators at Byron Generating Station terminated the Unusual Event at 8 p.m. today, after the return of power to Unit 2.

“Our diesel generators performed as expected in providing continuous electricity to the unit during the Unusual Event. Plant teams will now focus on a safe and measured approach to returning Unit 2 to the electrical grid,” said Byron Station Site Vice President Tim Tulon.

Station personnel are in communication with local, state and federal officials, including the U.S. Nuclear Regulatory Commission on the facility’s status.

The Unusual Event, which was declared Monday, is the lowest of the four emergency classifications as established by the NRC.

Byron’s Unit 1 continues to safely supply electricity to customers.

Exelon Nuclear officials say an equipment failure in a switchyard near the plant triggered the automatic shutdown of Unit 2.

The company, which continues to investigate the shutdown, said the plant is “in a safe and stable condition with no impact to public safety.” The plant is about 20 miles southwest of Rockford.

Meanwhile, officials from the state and federal governments were planning special inspections in and around the plant.

Officials from the Illinois Emergency Management Agency were at the plant today collecting water and vegetation to confirm that steam released during the event posed no hazards to people. The release of steam relieved pressure within the reactor.

IEMA wants to ensure that radioactive tritium that was in steam released after the reactor shutdown is at safe levels.

Results should be available in a few days.

“While we don’t expect to find harmful levels of tritium from the steam release at Byron, I believe it’s prudent to verify what levels are present,” said Jonathon Monken, IEMA director.

The NRC said it would investigate how the plant’s employees and systems responded to the loss of power, and for any corrective actions the plant is planning.

The NRC expects to have a report within 45 days of completing its inspection.

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NRC wants U.S. nuclear operators to adopt new seismic model

Dominion Virginia Power's North Anna Power Station in Mineral, Virginia is pictured in this undated photograph obtained on August 23, 2011. REUTERS/Dominion Power/Handout

Tue Jan 31, 2012 12:40pm EST

(Reuters) - The Nuclear Regulatory Commission said Tuesday the agency wants nuclear plant operators in the central and eastern United States to use a new seismic model to reassess the potential for earthquakes in their area.

The study comes almost a year after the disaster in Japan in March when an earthquake and tsunami damaged the Fukushima Daiichi nuclear power plant, causing reactor fuel meltdowns and radiation releases.

It also follows a magnitude 5.8 earthquake in August in Virginia that shut the two reactors at the North Anna nuclear power plant for about three months and a much smaller magnitude 3.2 earthquake Monday night that had no impact on the Virginia plant.

The study focused on the eastern and central parts of the United States because that area is considered a "stable continental region" where big earthquakes are rare. The study sponsors said nuclear sites in the western part of the country, where earthquakes are more common, will need to continue developing site-specific seismic models for their use.

The study, which gathered historical earthquake and geological data from 1568 through 2008, determined the largest potential earthquakes in the eastern and central parts of the country could occur near New Madrid, Missouri, and also in Charleston, South Carolina, where large magnitude seismic activity has occurred in the past.

There are no nuclear power plants within 100 miles of either city.

The central and eastern United States however is home to 90 reactors, 22 potential new sites and five Department of Energy (DOE) nuclear facilities, the study said.

Some of the nation's biggest nuclear power operators include units of Exelon Corp, Entergy Corp, Duke Energy and Progress Energy.

Overall, there are 104 operating power reactors in the United States, providing about 20 percent of the nation's power, and proposals to build up to three dozen new reactors mostly in the eastern half of the country.

The four-year study cost about $7 million and was sponsored by the Electric Power Research Institute (EPRI), which conducts research on issues related to the electric power industry, the DOE and the NRC.

Although the project sponsors said they did not undertake the new seismic study in response to the Fukushima or Virginia earthquakes in 2011, the NRC said its call for nuclear operators to re-evaluate seismic hazards was part of the agency's implementation of lessons learned from the events at Fukushima.

The new seismic model will replace previous models used by industry and government since the late 1980s.

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UN nuclear agency approves Japan's stress tests

TOKYO | Mon Jan 30, 2012 10:04pm EST

Jan 31 (Reuters) - U.N. nuclear experts on Tuesday gave their backing to stress tests aimed at showing Japan's nuclear plants can withstand the sort of disasters that devastated the Fukushima plant last year, potentially bolstering a government campaign to restart idled reactors and avoid a summer power crunch.

But the government still faces an uphill battle to restore tattered public trust in the nation's power utilities after the March 11 earthquake and tsunami triggered the world's worst nuclear crisis in a quarter century.

The Vienna-based International Atomic Agency's (IAEA) team was in Japan at the request of the government to review stress tests conducted by its watchdog Nuclear and Industrial Safety Agency (NISA) on the country's halted nuclear reactors in a bid to verify their safety.

"We concluded that NISA's instructions to power plants an its review process for the comprehensive safety assessments are generally consistent with IAEA safety standards," James Lyons, the leader of the 10-member IAEA team, said in a statement.

Stress tests are computer simulations that evaluate a nuclear reactor's resilience to severe events, such as earthquakes and tsunamis.

NISA completed a review of the stress tests earlier in January and said they showed reactors at Fukui prefecture's Ohi plant, the first ones it assessed, were capable of withstanding a severe shock similar to the magnitude 9.0 earthquake and massive tsunami that wrecked the Fukushima plant.

Some experts, however, have questioned the validity of the stress tests, charging the IAEA's visit was just for show.

"It is obvious that a visit by an international organisation advocating nuclear power is part of a political agenda that is built into a story already finished in advance," said University of Tokyo professor Hiromitsu Ino and former nuclear plant design engineer Masashi Goto in a joint statement last week.

Ino and Goto, who serve on a committee that advises on NISA's review of the stress tests, said the tests were insufficient as they only simulate one natural disaster at a time and do not take into account the possibility of the sort of equipment failure and human error seen at Fukushima.

ENERGY POLICY SHIFT

In another effort to restore public confidence in nuclear power, the cabinet on Tuesday approved bills that would set up a new nuclear safety agency, separating regulation of the industry from the trade and industry ministry, which has promoted nuclear power and came under criticism for its cozy ties with utilities.

The Fukushima disaster has prompted a major shift in Japan's energy policy.

The resource-poor nation had aimed to increase the share of nuclear power to more than half of the electricity supply by 2030 before the disaster, but now looks to reduce its reliance on nuclear power and raise the role renewable sources such as wind and solar power.

Before the Fukushima meltdowns, nuclear power covered about a third of Japan's electricity needs, but now only three out of the country's 54 nuclear reactors are in operation after being damaged or taken off-line for checks and the rest likely to be halted by spring. The government hopes the stress tests will help persuade a wary public that it is safe to restart some of the reactors and avoid an economically crippling power crunch during the peak summer season.

Local governments hosting nuclear plants, however, have said the stress tests were not sufficient to allow them to give their approval, with some requesting that findings from the Fukushima disaster be considered in drafting new safety standards as well.

There is no legal requirement for local authorities to sign off on restarts but custom requires their approval , and riding roughshod over public opinion would be risky for a five-month old government which has seen its ratings slide over its tax hike plans and some ministers' blunders.

" A utility would not be violating any law if it went ahead and restarted a reactor after properly completing scheduled maintenance. But the Fukushima accident has heighten e d public concern over nuclear safety, making local consent an important part of the restart process ," a trade ministry official said.

Japan had promoted nuclear power as safe, cheap and clean before the Fukushima crisis, but the accident destroyed that "safety myth".

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Illinois nuclear reactor shutdown probed

January 31, 2012 6:14 AM


In this March 2011 photo, steam escapes from Exelon Corp.'s nuclear plant in Byron, Ill.


(AP)

CHICAGO - Officials are investigating the events surrounding a power failure at a nuclear reactor in northern Illinois, where steam was vented to reduce pressure after it shut down.

After the shut down Monday morning at Exelon Nuclear's Byron Generating Station, operators began releasing steam to cool the reactor from the part of the plant where turbines are producing electricity, not from within the nuclear reactor itself, officials said. The steam contains low levels of tritium, a radioactive form of hydrogen, but federal and plant officials insisted the levels were safe for workers and the public.

Diesel generators were supplying the reactor with electricity, though it hasn't been generating power during the investigation into what happened. One question is why smoke was seen from an onsite station transformer, though no evidence of a fire was found when the plant's fire brigade responded, U.S. Nuclear Regulatory Commission spokeswoman Viktoria Mitlyng said.

Exelon Nuclear officials believe a failed piece of equipment at a switchyard at the plant about 95 miles northwest of Chicago caused the shutdown, but they were still investigating an exact cause. The switchyard is similar to a large substation that delivers power to the plant from the electrical grid and from the plant to the electrical grid.

The commission declared the incident an "unusual event," the lowest of four levels of emergency. Commission officials also said the release of tritium was expected.

Mitlyng said officials can't yet calculate how much tritium was being released. They know the amounts were small because monitors around the plant didn't show increased levels of radiation, she said.

Tritium molecules are so microscopic that small amounts are able to pass from radioactive steam that originates in the reactor through tubing and into the water used to cool turbines and other equipment outside the reactor, Mitlyng said. The steam that was being released was coming from the turbine side.

Tritium is relatively short-lived and penetrates the body weakly through the air compared to other radioactive contaminants.

Releasing steam helps "take away some of that energy still being produced by nuclear reaction but that doesn't have anywhere to go now," Mitlyng said. Even though the turbine is not turning to produce electricity, she said, "you still need to cool the equipment."

Candace Humphrey, Ogle County's emergency management coordinator, said county officials were notified of the incident as soon as it happened and that public safety was never in danger.

"It was standard procedure that they would notify county officials," she said. "There is always concern. But, it never crossed my mind that there was any danger to the people of Ogle County."

Another reactor at the plant was operating normally.

In March 2008, federal officials said they were investigating a problem with electrical transformers at the plant after outside power to a unit was interrupted.

In an unrelated issue last April, the commission said it was conducting special inspections of backup water pumps at the Byron and Braidwood generating stations after the agency's inspectors raised concerns about whether the pumps would be able to cool the reactors if the normal system wasn't working. The plants' operator, Exelon Corp., initially said the pumps would work but later concluded they wouldn't.


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France must extend nuclear reactors' lifespan-audit

Tue Jan 31, 2012 6:19am EST

* Some 22 nuclear reactors will reach 40 years old by 2022

* EDF wants to extend reactors lifespan to 60 years

* Heavy investments needed in short, medium term

PARIS, Jan 31 (Reuters) - France has no option but to extend the lifespan of its nuclear power plants as any investments to renew its nuclear capacity or to increase its reliance on other forms of energy would be too costly and come too late, the French Court of Audit said.

The French independent government body, which is charged with conducting financial and legislative audits, said in a report that a lack of investment decisions to build new reactors meant there were few choices left.

"...In the absence of investment decisions an implicit decision has already been made which commits France either to prolong the reactors' lifespan beyond 40 years or to quickly change the energy mix, which implies more investments," said the report on the costs of the French nuclear power sector.

By the end of 2022, 22 out the 58 reactors in France, the world's most nuclear-reliant country, will have been in operation for 40 years.

The report, published on Tuesday, said that if the reactors' lifespan was limited to 40 years this would mean having to build 11 new-generation reactors by 2022.


"Putting in place such an investment programme in the short term is highly unlikely, even impossible ...," it said.

State-owned utility EDF, which operates all of the France's reactors, has said it aims to extend their lifespan to 60 years but there is no official limit to their functioning. The bulk of French reactors were built in the 1980s and 1990s.

The court of Audit also said that to maintain the current level of electricity production, heavy investments would be needed in the short and medium term, including a doubling of maintenance investments, which would in turn push production costs up by 10 percent.

"This means that in the absence of investment decisions an implicit decision has already been made which commits France either to prolong the reactors' lifespan beyond 40 years or to quickly change the energy mix, which implies more investments," the report added.

The Court recommended that the choice of the future of the energy mix should not be made in an implicit manner but that a strategy should be explicitly elaborated, debated and adopted.

The report's conclusions echo a leaked draft government study on Monday, saying that extending the lifetime of France's reactors would be a cheaper investment option to 2035-2040 than building any type of new power plant.

The leaked government study on energy scenarios for France until 2050, due to be published in its final form on Feb. 13, shows that extending the operation of nuclear plants would cost 680 million to 860 million euros per reactor.

That would compare to the roughly 5 billion euros ($6.56 billion)it would cost to build a new-generation reactor such as the 1,600 megawatt EPR reactor constructed by state-controlled Areva.

The Court of Audit report, commissioned by Prime Minister Francois Fillon in May 2011, comes as France's reliance on nuclear power has become part of the country's presidential campaign in the aftermath of Japan's nuclear disaster in March.

While the ruling UMP party plans to maintain the country's nuclear share of 75 percent in the electricity mix, the highest in the world, socialist candidate Francois Hollande said he would bring down that share to 50 percent by 2025.

Hollande, campaigning against President Nicolas Sarkozy, has said that if elected he would close France's oldest plant, Fessenheim, toning down earlier plans as part of a pact with the Green party to shut 24 reactors by 2025.

The Fessenheim plant, one of 19 across the country, houses two 900-megawatt reactors.

France first opted for a full-blown nuclear energy programme with minimal public debate after the first oil crisis in 1974 and continued to support nuclear power after the 1986 Chernobyl disaster. ($1 = 0.7625 euros) (Reporting by Benjamin Mallet; Writing by Caroline Jacobs; Editing by Muriel Boselli)


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Monday, January 30, 2012

Reactor shuts down, releases steam at Illinois nuclear plant after losing outside power

By Associated Press, Updated: Monday, January 30, 1:18 PM

BYRON, Ill. — A nuclear reactor at a northern Illinois plant shut down Monday after losing power, and steam was being vented to reduce pressure, according to officials from Exelon Nuclear and federal regulators.

Unit 2 at Byron Generating Station shut down around 10:18 a.m., after losing power from an off-site source, Exelon officials said. Diesel generators began supplying power to the plant equipment and operators began releasing steam from the non-nuclear side of the plant to help cool the reactor, officials said.

Even though the turbine is not turning to produce electricity, “you still need to cool the equipment.” said U.S. Nuclear Regulatory Commission spokeswoman Viktoria Mitlyng. Releasing steam helps “take away some of that energy still being produced by nuclear reaction but that doesn’t have anywhere to go now.”

The steam contains low levels of radioactive tritium, but the levels are safe for workers and the public, federal and plant officials said.

Unit 1 was operating normally while engineers investigate why Unit 2 lost power, which comes into the plant from the outside power grid, Mitlyng said. Smoke was seen from an onsite station transformer, she said, but no evidence of a fire was found when the plant’s fire brigade responded.

Exelon spokesman Paul Dempsey said there is “no reason we can pinpoint right now” for the power loss.

Mitlyng said Nuclear Regulatory Commission inspectors were in the control room at Byron and in constant contact with the agency’s incident response center in Lisle, Ill.

Byron Generating Station is in Ogle County, about 95 miles northwest of Chicago.

In March 2008, federal officials said they were investigating a problem with electrical transformers at the plant after outside power to a unit was interrupted.

In an unrelated issue last April, the commission said it was conducting special inspections of backup water pumps at the Byron and Braidwood generating stations after the agency’s inspectors raised concerns about whether the pumps would be able to cool the reactors if the normal system wasn’t working. The plants’ operator, Exelon Corp., initially said the pumps would work but later concluded they wouldn’t.

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