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Showing posts with label Plants. Show all posts
Showing posts with label Plants. Show all posts

Wednesday, February 19, 2014

Chernobyl 2? Watching the world’s aging power plants

North Korea satellite Yongbyon.jpg Satellite imagery from May 2013 of the Yongbyon Nuclear Scientific Research Center in North Korea.DigitalGlobe

Moscow power plant.jpg The Kalinin nuclear power plant in Russia.IAEA

North Korea’s aging Yongbyon nuclear power plant will probably not lead to a nuclear catastrophe, despite an alarming report calling it the next Chernobyl -- but the danger posed by the world’s aging reactors is real nonetheless.

The defense publication Jane’s recently detailed efforts to bring the small Yongbyon reactor back online, saying they could lead to a meltdown like the  Chernobyl incident in 1986. According to the article, Yongbyon uses obsolete technology that was responsible for a 1957 accident in the United Kingdom and “could lead to a disaster worse than the Ukrainian one."

But Joel Wit, a former U.S. State Department official who manages the 38 North blog for the U.S.-Korea Institute at the Johns Hopkins School of Advanced International Studies, told FoxNews.com he disagreed strongly with the Jane’s report. And when Ferenc Dalnoki-Veress, a scientist-in-residence with the James Martin Center for Nonproliferation Studies, ran an analysis, he concluded that the scale of the reactor posed a far smaller threat than Jane’s suggested.

“In the worst case scenario, the accident would release a dose 500,000 times lower than Chernobyl,” Dalnoki-Veress said.

'The Russians are running into this, the French are running into this, the Japanese are running into this. It’s a big issue.'

- Jon B. Wolfsthal, deputy director of California’s James Martin Center

Nonetheless, the average nuclear power plant is more than 20 years old and is anticipated to last no more than 30 or 40 years, leaving the world facing a potential crisis: How safe are aging nuclear power plants?

No country has a greater reliance on nuclear power than the U.S., which had 104 reactors online in 2011. But all of them have been online since 1990, and most since 1980.

“By far the largest problem is here in the U.S.,” said Jon B. Wolfsthal, deputy director of California’s James Martin Center.

“But the Russians are running into this, the French are running into this, the Japanese are running into this. It’s a big issue.”  

France had 58 nuclear reactors connected to the power grid in 2011, according to a 2012 reference work by the International Atomic Energy Agency (IAEA). Fifty-six of them have been operating since 1990, and 43 have been online since 1985, making them around 30 years old. Japan is in a similar situation, with 51 plants online in 2011 (not including the Fukushima plant), nearly all of which were in operation 20 years earlier.

There were 435 nuclear power plants online worldwide as of New Year’s Eve, 2011. As of that date, 138 others had been permanently shut down, though only 11 cited obsolescence as the reason.

Plot construction of nuclear plants on a grid and you’ll see a near perfect bell curve; most of the world’s power plants were built during the ’60s, ’70s and ’80s, peaking between 1974 and 1976, a three-year span that saw construction begin on 118 plants worldwide. By comparison, ground was broken on just 29 plants throughout the ’90s.

But nuclear power is seeing a renaissance. China has 42 power plants planned for construction, according to the IAEA, and Russia has 35. As of Dec. 31, 2011, 114 were planned, and an additional 65 reactors were under construction.

Yet Chris Englefield, a senior manager in radioactive substances regulation for the U.K. Environment Agency, noted in a 2012 paper that there are no nuclear security specialists. He says there is a need to professionalize security and to facilitate minimum standards of competence and regulatory procedures.

The U.N.’s IAEA acts as a nuclear watchdog at times, but it also helps to do just that, aiding member countries in maintaining power plants to tease extra years from them while preventing incidents.

“One of the IAEA’s key missions is to support its member states in their efforts to improve nuclear safety,” said IAEA spokesman Serge Gas. “In that context, the agency does not single out individual nations, but rather encourages all of them to improve all the time.”

Jeremy A. Kaplan is Science and Technology editor at FoxNews.com, where he heads up coverage of gadgets, the online world, space travel, nature, the environment, and more. Prior to joining Fox, he was executive editor of PC Magazine, co-host of the Fastest Geek competition, and a founding editor of GoodCleanTech.


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Sunday, June 9, 2013

How Plants May Help Offset Global Warming

Could plants help to slow the march of global warming?

It's possible, suggests a new study, which finds that as climates warm around the world, plants may respond by releasing more aerosol particles into the atmosphere.

The research, published online April 28 in the journal Nature Geoscience, finds that these natural aerosols can fuel cloud formation, which may help cool a warming climate. [The Reality of Climate Change: 10 Myths Busted]

Aerosols are fine particles of solid or liquid matter, suspended in air. Most of the aerosol particles in Earth's atmosphere come from human activities such as vehicle exhaust, according to the environmental blog The Carbon Brief. Volcanic eruptions also contribute some aerosols to the atmosphere.

But a small percentage of atmospheric aerosols come from living plants, according to a news release from the International Institute for Applied Systems Analysis (IIASA), which co-sponsored the study.

Plants release gases such as water vapor and oxygen; these combine with the aerosols released from plants to form larger airborne particles that reflect sunlight and form cloud droplets.

"Everyone knows the scent of the forest," Ari Asmi, University of Helsinki researcher and co-author of the study, said in a statement. "That scent is made up of these gases."

To measure the cooling effect, researchers collected data from 11 sites around the world, measuring aerosol particle concentrations, plant gases and temperatures.

In warmer temperatures, it was revealed, plants emit more of the gases that stick to aerosol particles. These can lead to cloud formation and, as a result of cloud cover, cooler temperatures.

Other natural phenomenon may help to cool the planet: Some researchers believe that phytoplankton — microscopic plants that drift on ocean currents — may reduce carbon dioxide levels in the atmosphere and lower the atmosphere's temperature.

Other research finds that tropical rainforests, which also absorb massive amounts of carbon dioxide and release water vapor that forms clouds, are critical to stabilizing atmospheric temperatures.

It's unclear how much cooling might actually occur as a result of so-called "biogenic" aerosols.

"This does not save us from climate warming," Pauli Paasonen, lead author of the study, said in the release.

Though in some areas, such as the forests of Finland and Canada, the cooling effect can be as large as 30 percent, the overall global effect is very small, offsetting only about 1 percent of global warming, according to the study.

Nonetheless, the impact of plant-based aerosol formation is an important element in fine-tuning climate forecast models, the researchers believe.

"Aerosol effects on climate are one of the main uncertainties in climate models," Paasonen said in the release. "Understanding this mechanism could help us reduce those uncertainties and make the models better."

Follow Marc Lallanilla on Twitter and Google+. Follow us @livescience, Facebook & Google+. Original article on LiveScience.com.

Copyright 2013 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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