Category: In Service

54 Billion Tons of CO2 Emissions Displaced By Nuclear Energy and Natural Gas

54 billion tons of co2 emissions displaced by nuclear energy and natural gas 63964 54 Billion Tons of CO2 Emissions Displaced By Nuclear Energy and Natural Gas

 

According to a new analysis by the Breakthrough Institute, energy produced by nuclear fission and natural gas has saved the country 54 billion tons of carbon dioxide emissions since 1950. Had America’s carbon intensity remained constant at its 1940 levels, today’s annual carbon dioxide emissions would be approximately 1.7 billion tons greater.

In the 1950s, natural gas saw increased popularity, reducing carbon emissions by replacing coal. In the 1970s, nuclear power – which emits no carbon – began expanding as one of the nation’s energy suppliers. In the 1990s renewable geothermal, wind, and solar energy started supplying significant shares of energy.

Though geothermal, wind and solar power had a relatively modest impact on emissions reductions, accounting for 1.5 billion tons over the 60-year period, the switch from dirty energy to nuclear power accounted for half of the total emissions reductions, or 28.1 billion tons over the 60-year period. Similarly, the switch to natural gas accounted for a reduction of 25.9 billion tons.

54 billion tons of co2 emissions displaced by nuclear energy and natural gas 95578 54 Billion Tons of CO2 Emissions Displaced By Nuclear Energy and Natural Gas

 

A paper authored by NASA scientists James Hansen and Pushker Kharecha found that nuclear power could prevent “80–240 [gigatons of carbon dioxide equivalent] emissions due to fossil fuels by midcentury, depending on which fuel it replaces.”

Additionally, Hansen and Kharecha found that nuclear energy prevented an average of 420 000–7.04 million deaths. In fact, scientists estimate that, had the world’s nuclear power been replaced by the burning of coal and natural gas between the years of 1979 and 2001, air pollution would have led to the deaths of nearly 2 million more people.

According to Scientific American, in the 2000-2009 period alone, nuclear power may have prevented an average of 76,000 deaths:

“Even the worst nuclear accident in history (Chernobyl) caused about 40 deaths these include 28 immediate responders and about 15 deaths caused among 6000 victims of excess cancers. There have been no deaths attributable to the Three Mile Island accident. And while the verdict on Fukushima is still not definitive, the latest report on the accident predicts no direct deaths and a much lower exposure to radiation for the surrounding population than that purported to lead to fatal cancers.”

“The bottom line is that, even assuming pessimistic scenarios, the number of deaths caused by nuclear power is a minuscule fraction of those lives which were saved by nuclear power replacing fossil fuels.”

Despite nuclear energy’s potential, Hansen and Kharecha found that an expansion of natural gas would not be as effective at saving lives and reducing carbon emissions:

“By contrast, we assess that large-scale expansion of unconstrained natural gas use would not mitigate the climate problem and would cause far more deaths than expansion of nuclear power.”

Californians are staunchly against the expansion of nuclear energy, however. A PPIC survey showed that 58 percent of likely voters in the state oppose new nuclear projects. California also has a moratorium on future nuclear projects until waste storage methods are developed. Natural gas is currently the most significant source of energy in California.

There are currently 65 operational nuclear power plants in the US, accounting for 104 nuclear reactors in total. Since 1990, nuclear energy has accounted for 20 percent of the country’s electricity generation.

Source – IVN News 
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Wylfa: Anglesey nuclear reactor ‘could run until 2015

Wylfa: Anglesey nuclear reactor ‘could run until 2015

Wylfa nuclear power plant, Anglesey
Magnox wants to maximise the generating potential of Wylfa’s remaining fuel

The planned shut down of Britain’s oldest nuclear reactor on Anglesey could be extended by 15 months if safety inspectors approve the work, says its operator.

The Wylfa reactor 1 was expected to stop producing power in 2014, but it could continue until December 2015.

Magnox said it wanted to ensure it maximised any electricity generating potential in the remaining fuel.

The plans are subject to Periodic Safety Review (PSR) approval.

The 490-megawatt reactor has been operating for 42 years.

Reviews are carried out by nuclear site licence holders every 10 years to establish whether reactors are safe to run and these are monitored by Britain’s nuclear regulator.

Reactor 2 at the same nuclear plant was shut down for good last year.

A Magnox spokesman said: “Operations at Wylfa, by transferring fuel from reactor 2 which has shut-down to reactor 1 which is operational, are going well.

“As a precaution, in the event that there are any delays to the current defueling schedule, Magnox are making preparations to extend the generating period for the station to ensure we maximise any electricity generating potential in the remaining fuel.

New power stations

“To extend the end of generation date to December 2015, we will need to submit a periodic safety review, gain consent from our regulator, the Office for Nuclear Regulation, and secure approval from the site’s owner the Nuclear Decommissioning Authority and the (UK) government’s Department for Energy and Climate Change.”

A site adjacent to the existing power plant is earmarked for the construction of a new nuclear power station.

Japan’s Hitachi, which last year bought Horizon that has a licence to build new reactors at Wylfa, plans to build two to three reactors at Wylfa and another two to three at a site in Oldbury near Bristol.

Source – BBC News

Ten more years for Smolensk reactor

Ten more years for Smolensk reactor

The Russian nuclear safety regulator has agreed to extend the operating licence of Smolensk 1 by ten years, enabling nuclear generation to continue until a replacement plant is built.

File:Smolensk Nuclear Power Plant.jpg

Image (Wikipedia)

The 925 MWe RBMK-1000 reactor was first connected to the grid in 1982 and has been extensively modernised as part of a RUB45 billion ($1.5 billion) package covering the three unit site – announced by Rosatom at the beginning of 2012. This followed an International Atomic Energy Agency safety mission to the plant carried out in September 2011, which noted good practices and identified areas for improvement.

The ten-year extension will see the reactor operate until 25 December 2022, a lifespan of 40 years, although a 2010 Rosatom plan was open to the possibility of Russia’s RBMKs operating for up to 45 years. The existing Smolensk reactors are set to be replaced by a new plant, Smolensk Phase II, which will consist of two to four VVER-1200 reactors. Although no firm date has yet been scheduled, the first of these is pencilled in to come on-line by 2024.

RBMK reactors became the focus of much attention internationally following the 1986 Chernobyl nuclear accident which involved a reactor of that design. Russia responded by instigating a program of operational and technical improvement at its 11 operational RBMK units – which still account for approximately 45% of the country’s nuclear electricity production. One more RBMK remains under construction as the fifth unit of the Kursk nuclear power plant.

Over the past ten years performance of the RBMK reactors has steadily improved, with an average 2011 load factor of 81.5% compared to a lifetime value of 63.9% according to data collected by trade journal Nuclear Engineering International.

Source: World Nuclear News

Lord Hutton on nuclear energy – Interview

Lord Hutton on nuclear energy – Interview

Anoosh Chakelian (Editor – Total Politics) talks to Lord Hutton, chair of the Nuclear Industry Association, former business secretary, and Labour’s ‘nuclear renaissance man’

AC: Your pro-nuclear stance in government was quite outspoken at the time. Why were you so bold?

JH: It was something I’d thought about very carefully, both inside and outside of government. And it’s something I believed – and still believe – is essential if we’re going to create the right kind of balanced energy policy for the future and to invest in new technologies, which is incredibly important. Civil nuclear energy is going to be globally significant for business, and Britain should be part of that. It’s going to happen, and we’ve got some fantastic engineering and nuclear skills in Britain that can really lay the foundations for tens of thousands of important jobs.

AC: What were the main arguments you came up against when you put these views forward?

JH: In government, the debate on climate change shifted the parameters in favour of nuclear. We needed to decarbonise our power generation industry, and nuclear is the cheapest form of low-carbon energy. Outside of government, yes, of course there are arguments that people put up against nuclear, but it is interesting how public support is very strong for it – I think they understand its benefits.

AC: And what about its detractors?

JH: The detractors, the opponents… well, some of it is ideological, some of it is environmental – I do respect that energy choices are sometimes difficult ones, and there isn’t an easy way forward. By all means have a mix of energy with renewable sources as part of the way forward, but we shouldn’t kid ourselves; if we really are serious about getting ourselves off the fossil fuel fix, we’re going to need more electricity, not less. The job of the industry is to continue to make the modern case for nuclear – low carbon, efficient, safe.

AC: Is the government providing enough financial certainty for potential nuclear investors in the UK?

JH: There are two very strong bids in, and I think there is an appetite out there among investors to make the decision on nuclear in the UK. There is, however, more to be done, and the government has to do it, to reassure investors about the certainty surrounding these new agreements in the electricity market. I think this is one of those cases where we’ve got to realise that the market has its limitations – it’s not on its own going to make the switch to low-carbon sources of energy, because they’re not as cheap as the cheapest form of carbon. That’s the reality. So if we are serious, then it is first and foremost the responsibility of the government to set the market in the right direction, and if it can do that properly then I don’t think there will be an issue as far as investment is concerned.

AC: So is the government going the right way about this?

JH: Broadly it is. It’s trying to do the right thing, but the devil is in the detail. There is inevitably going to be some discussion about the detail of the policy. There is a complex set of discussions underway, and we’ve got to approach them in a realistic frame of mind. There are really big, strategic issues at stake here when it comes to securing the energy we need for the future at the best possible price.

AC: Is the government committing future energy users to very high prices by pursuing new nuclear build so vehemently?

JH: No, I don’t personally believe so. You’ve got to look at the costs of all of the low-carbon sources. It’s pretty clear now that offshore wind is at the high end of the scale of cost, and nuclear is at the low end. I personally accept that it’s likely that the move to low carbon – because we’re doing it quickly, we need to do it quickly – is going to come with a cost. However, bills would rise more slowly with nuclear than they would if we relied on other forms of low-carbon energy.

Source – NIA

Dungeness encourages young women to apply for nuclear apprenticeship

Dungeness encourages young women to apply for nuclear apprenticeship

 

Dungeness encourages young women to apply for nuclear apprenticeship

EDF Energy is encouraging young women to apply for its nuclear apprenticeship  scheme.
The company is holding an information day on 24 November at Dungeness B power station, Kent, to give prospective apprentices an insight into a career in nuclear energy.

While the programme is open to anyone meeting the criteria, EDF said it was particularly keen to recruit females.

Station director Martin Pearson said: “In the current climate, an apprenticeship offers a real alternative to going to university. Our scheme is very highly regarded and the sky really is the limit for our apprentices. Several members of EDF Energy’s executive team started with the company in this way, so the message is this course could be the start of a truly amazing engineering career.”

Source – Utility Week

Curtiss-Wright signs up for SMR work

Curtiss-Wright signs up for SMR work

NuScale Power has enlisted engineering company Curtiss-Wright to design the control rod drive mechanisms (CRDMs) for its proposed small modular reactor (SMR).

Under a contract signed with NuScale, Curtiss-Wright will design the CRDMs – which control the insertion and removal of control rod assemblies into reactors – at its plant in Mount Pleasant, Pennsylvania. The initial contract covers just the design phase of the program.

Curtiss-Wright has supplied over 5000 mechanisms to nuclear power plants around the world, including the first-ever installation on a reactor head in the USA.

A cutaway of a NuScale SMR
(Image: NuScale)

NuScale is developing a 45 MWe self-contained pressurized water reactor and generator set, which would be factory made and shipped for deployment in sets of up to 12. These could result in scalable nuclear power plants with capacities from 45 MWe to 540 MWe.The reactor unit uses conventional nuclear fuel assemblies of under 5% uranium-235, which would require replacement only after about two years. The core would be cooled by natural circulation, requiring fewer components and safety systems.

NuScale is one of three developers of SMR technology – the other two being Babcock & Wilcox and Westinghouse – who have submitted applications to the US Department of Energy for funding to support first-of-a-kind engineering, design certification and licensing.

Source – WNN

Nuclear Plant Powered by Spent Fuel

Nuclear Plant Powered by Spent Fuel

Reactors could use existing stockpiles of nuclear waste to produce electricity for the world through 2083.

Radioactive sites like this one deep inside the Yucca Mountain Nuclear Waste Repository in Nevada would be almost unnecessary because a salt reactor reduces the majority of nuclear waste’s radioactive lifetime. David Howells / Corbis Images

An old nuclear technology is getting another look, and it could clean, emission-free electricity, while at the same solving the problem of nuclear waste. It’s called a molten salt reactor, and it’s an idea that dates to the late 1950s. A start-up called Transatomic Power, based in Cambridge, Mass., is working on a newer version that uses nuclear waste as fuel. Transatomic’s founders are Russ Wilcox, formerly the CEO of E-Ink, and Leslie Dewan and Mark Massie, two MIT students.

The reactor still makes waste, but what comes out is radioactive for only 300 years, as opposed to millennia. Transatomic calls it a Waste Annihilating Molten Salt Reactor, or WAMSR.

“It’s stuff that is in the middle of the periodic table,” said Dewan, Transatomic’s chief science officer. “It’s a lot easier to isolate.”

A big selling point of this design is that it would help deal with the nuclear waste problem. The Nuclear Energy Institute says there are some 67,000 metric tons of uranium from fuel in the United States alone. It can also be built smaller at lower costs out of modular parts.

The WAMSR can do this because unlike current reactors, it doesn’t need to use enriched uranium as fuel, and the fuel itself doubles as a coolant. No need to build this near a water source like an ocean or river that can ultimately flood and cause damage.

But first a bit about how nuclear plants work: In commercial nuclear reactors, a core houses fuel rods that contain uranium oxide pellets. The radioactivity from the uranium produces heat. To make electricity, water is piped into the core and turned into steam, which is then used to drive generators. This is called the “light water” design.

 To produce enough heat for the steam, the uranium needs to be highly radioactive. That requires purified or enriched uranium. For a power plant that means that up to about 20 percent of it has to be U-235, an isotope that makes up less than 1 percent of the naturally occurring uranium. (Most of the time the enrichment percentage is lower, on the order of five percent — the higher levels are used in research reactors and naval vessels).

As the fuel is “burned,” the uranium decays into other elements, including plutonium, zirconium, cesium, xenon and iodine. Eventually, enough other elements mix in with the uranium that the nuclear reactions slow down, reducing the efficiency of boiling the water. The fuel is then called “subcritical,” or spent, and is put into a waste storage facility.

That’s where the WAMSR comes in. Spent fuel from other reactors is dissolved in fluorine to make a molten “salt,” a chemical whose elements are bound together by their positive and negative charges. The molten salt is pumped out of the core and into a heat exchanger, where the water is boiled to drive a turbine. Since the heat energy is being transferred to the water, the fuel cools down.

This type of reactor was first proposed as a way of powering a bomber; in the 1960s and 70s there was one operated at the Oak Ridge National Laboratory. But the nuclear industry had settled on the light water reactors, and that became the industry standard.

Small May Be Beautiful For Nuclear Power

Because the molten salt behaves like a liquid, it’s easier to get it into a shape that allows for self-sustaining reactions, Dewan said. The shape matters because to make sure that neutrons and nuclei hit others (and sustain the fission) it’s necessary to reduce the surface area of the fuel as much as possible. A sphere is the perfect shape, but a cylinder works as well. The fission reactions in the molten salt “burn” more of the uranium in it, so eventually much more turns into other elements that don’t stay radioactive for so long.

The radioactivity dies down more quickly, too, so it’s easier to build containment facilities. Designing a structure to last a few centuries has been done (think of the average cathedral). But to build one that will last ten or a hundred times as long is much harder; let alone figuring out how to warn future people of the danger when it isn’t likely anyone will speak English — or even remember that English existed.

The fuel is also safer. When accidents have happened in power plants, such as at Fukushima in Japan, it was because the cooling systems failed. At Fukushima the generators that powered the water pumps were flooded by a tsunami. The heat built up in the reactor core until there was a meltdown. The result was a release of hydrogen, which exploded.

The WAMSR’s core is “plugged” with a chunk of solid material that is actively cooled. If that cooling fails, then the plug melts and the molten salt drains out into a pool Once outside of the reactor vessel it will simply cool off and eventually solidify – and since it isn’t in the right shape anymore, the fission reactions won’t be self-sustaining. A failure of the cooling system power would stop the reactor, rather than leading to a meltdown.

With all these pluses, outside experts say there are still some problems. Transatomic isn’t releasing the details of its design, though Dewan and Massie outlined the basics in a TEDx talk on Nov. 1. She said some of these issues have been addressed.

First is the process of taking the fuel out of the reactor vessel, and replacing it. A number of the fission products in nuclear waste are gases — notably radioactive iodine, xenon, and cesium. “It’s one thing to deal with the solids, it’s another to deal with the gaseous fission products,” said Jim Malone, chief nuclear fuel development officer at Lightbridge, a company that is working on a thorium reactor design. He said there has to be some method of containment.

Dewan said the fuel would be processed by draining off some of it and removing the “poisons,” or elements that slow the nuclear reactions down. But that requires a lot of heavy-duty chemical processing.

As one of the selling points of this kind of reactor is that it would be cheaper to build, having that type of processing plant on-site might alter that calculation, said Tanju Sofu, department manager of the nuclear engineering division at Argonne National Laboratory. “You’d probably need a fuel cycle facility attached to the plant,” he said.

Sofu also noted that molten salt needs to be pumped around, and any moving parts have to function for a long time. Many metals when exposed to radiation — especially the neutrons produced in a reactor — become brittle over time. Replacing parts inside the core raises the same containment problems that processing the fuel does.

Metallurgy and materials science have come a long way since 1959, and Dewan says there is a lot of experience in industry with pumping molten fluoride salts and doing maintenance on complex systems

Perhaps the biggest issue will be getting the nuclear fuel itself. Technically, nuclear waste is all property of the Department of Energy, said Mike Mayfield, director of the division of advanced reactors and rulemaking at the Nuclear Regulatory Commission. So there would need to be some discussion of how the fuel is getting processed and working out an agreement to get it.

Even with those obstacles, the WAMSR is still a worthwhile innovation, Sofu said. “In the 1990s the DoE did a study of next generation designs,” he said. “The molten salt reactor was one of the four or five most promising concepts. It has a lot of advantages in fuel cycle consideration and resource utilization.”

Source – Discovery News