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Last edited by Rubyait on 29-06-2005 21:12; edited 1 time in total

(Split from the Cold Fusion thread - Stu)

Frozen talks over fusion reactor warm up

Posted: 29-06-2005 09:32 Post subject:

Q&A: Nuclear fusion reactor

Posted: 30-06-2005 11:25 Post subject:

link to the ITER homepage

http://www.iter.org/index.htm

Posted: 01-07-2005 15:39 Post subject:

Apparently the one in oxfordshire uses 2% of the national grid when it first fires up :/

Posted: 01-07-2005 16:33 Post subject:

My father worked at the Oxfordshire site for over 30 years.Recently retired.

*insert proud smilie*

Posted: 03-07-2005 17:36 Post subject:

Is that site at Abingdon still operational Question

I remember going there in the late sixties to service time clocks for an onsite contractor.

Posted: 04-07-2005 20:11 Post subject:

Yeah its still going, and will be for another 5 years or so, albeit on a smaller scale than in recent years.It will still be helping with further research in preperation for the planned site in France.

Posted: 04-07-2005 22:44 Post subject:

Thanks for that. Was it called the JET Project or something similar; Joint European T... Question

Posted: 05-07-2005 09:41 Post subject:

No probs.Yeah, Joint European Torus.

Posted: 10-03-2006 11:07 Post subject:

No future for fusion power, says top scientist

Posted: 25-05-2006 10:27 Post subject:

Gigantic fusion reactor gets the green light

Posted: 26-05-2006 00:09 Post subject:

Nuclear fusion plasma problem tackled

Source

Posted: 09-09-2007 15:25 Post subject:

Hunting the holy grail of fusion
Last week a British initiative was agreed to unlock limitless energy. Can it work?
Jonathan Leake and Elizabeth Gibney

"The mighty Zeta: limitless fuel for millions of years” trumpeted the newspapers. It was January 25, 1958 and Britain’s media were alive with the news that the nation’s scientists had created the world’s first controlled fusion reaction. It was, they promised, the dawn of a new era, when power would be both limitless and free.

Alongside the stories were photographs of a giant machine, codenamed Zeta, whose existence had been one of the nation’s most closely guarded secrets, alongside the triumphant young scientists who had built it. The fanfare followed a news conference called the day before by Sir John Cockcroft, the Nobel prize-winning director of the government’s Harwell research laboratories and one of our most respected scientists.

His machine, he told the assembled media, had achieved temperatures of 5,000,000C – generating the world’s first controlled nuclear fusion reaction. “To Britain this discovery is greater than the Russian sput-nik,” he declared, promising a commercial fusion reactor within 20 years.

That was 49 years ago. Just a few months later Cockcroft quietly issued a press release. His researchers had, it seemed, been mistaken. Zeta had never achieved fusion. It had not even achieved temperatures of 5mC. The machine was a dud.

Cockcroft’s blunder was, however, far from the last. Over the years, fusion’s lure of limitless energy has tempted many more scientists and politicians into the same trap of wishful thinking. In 2002 one set of researchers announced that they had achieved bubble fusion, while in 1989 another group announced that they had achieved cold fusion. All have ended in retractions, recrimination and humiliation.

What, then, are we to make of a new announcement last week, again from Harwell, that Britain could once more be on the road to achieving nuclear fusion?

Professor Mike Dunne, of the Rutherford Appleton laboratory, is seeking a £500m grant from the European Union to build a machine that will, he hopes, finally achieve fusion. Last week he got the green light to start designing the machine and finding a site for it. Dunne was far more cautious that Cockcroft, warning that success will take many years and that it was far from guaranteed. Underneath it, however, lay the same hope: that Britain could lead the world into a new era where nuclear fusion provided almost limitless and very cheap energy.

“The problems are huge,” said Dunne. “But if we can solve it we will have a way of tackling climate change. The prize is too great to ignore.”

So, as £500m of taxpayers’ money heads towards yet another attempt at fusion, is there really a chance that scientists could harness the power of the sun or are they, like Cockcroft, simply deluded by hope? On the face of it, Dunne’s plans could seem just as fantastic as Cockcroft’s. His machine, called Hiper, would work by firing tiny pellets of hydrogen across a steel vacuum chamber. At a critical point along its trajectory, each pellet would be hit by laser light. The beams would be so powerful the pellet would be simultaneously crushed and heated, achieving temperatures of around 100,000,000C, about 10 times hotter than the sun.

At such temperatures the atoms that make up all matter are ripped apart. The outer electrons are stripped away and the hydrogen nuclei fly around at such fantastic speeds that when they collide they fuse. As they fuse, some of their mass is destroyed and converted into large amounts of energy in the form of heat, light and radiation. It is this energy that Dunne hopes to capture and turn into electricity.

“Fusion is basically nature’s solution to the energy problem,” said Dunne. “It’s how the sun and the stars work. If we can control it here on Earth then we really will have limitless energy.”

The principles of fusion have been known ever since Einstein showed the power locked up in atoms with his famous equation, . It showed that annihilating just a tiny amount of matter would release vast amounts of heat, light and radiation.

In 1952 the Americans used this to build the first hydrogen fusion bomb. The explosion wiped out an entire Pacific atoll using the energy liberated from destroying a few hundred grams of hydrogen. That event inspired other scientists who immediately realised fusion’s potential in both peace and war – and led to some extraordinary research.

Dunne’s project is, for example, partly inspired by a US military programme from the 1980s when researchers successfully started a fusion reaction in a pellet of hydrogen by blasting it with x-rays. But their method had a flaw for peaceful power generation, because the only way they could get powerful enough x-rays was by detonating an atomic bomb nearby – hardly sustainable.

Dunne’s calculations show that a powerful laser could do the same job. Designing such a machine is among the biggest hurdles that his team faces.

“The laser would be the most powerful ever built,” said Dunne. “It would generate pressure of around a billion atmospheres within the hydrogen pellet. That’s equivalent to 10 aircraft carriers sitting on your thumb. A large part of our research will be working out how to build such a machine.”

Dunne’s approach is realistic enough to have been endorsed by peer reviewers for the European commission. They have looked closely at the global advances in laser technology and concluded that Dunne’s machine could be feasible.

It is not just new technology which is opening doors for Dunne. His proposal also comes at just the right time with the twin threats of climate change and energy insecurity prompting renewed global interest in fusion as a potential source of power.

The European Union is, for example, already backing ITER, a much larger project under construction in France, which is also supported by Japan and America. It will attempt fusion by a completely different approach, using powerful magnetic fields to heat and contain the fusion fuel. The Americans are also going it alone with their National Ignition Facility under construction in California, which will use some of the world’s largest lasers for fusion research. Dunne hopes to use its work as a basis for his own.

“What we are seeing is a radical shift in the politics of energy,” said Malcolm Grim-ston, an expert in energy policy based at Chatham House, the think tank.

“In the 1990s, Europe and especially Britain had plentiful energy in the form of coal and North Sea oil and gas, so the interest in fusion research waned. In the past few years, however, climate change and the realisation that we are running out of oil and gas are promoting a longer-term view.

Fusion research has benefited from that.”

Studies by the International Energy Agency (IEA) illustrate the need. They show that the world consumed energy equivalent to 11.4 billion barrels of oil in 2004 and that this will rise to a predicted 17.1 billion barrels by 2030.

The IEA warns that one consequence will be a 55% increase in the amount of carbon dioxide emitted from energy production – at a time when climate change is becoming one of the most pressing global issues. “Fusion should never be seen as a way of guaranteeing energy security or as an excuse to shirk our responsibilities on cutting climate change emissions,” said Dunne.

“We don’t know how or when we will find it. For me it is a bit like the holy grail.”

http://www.timesonline.co.uk/tol/news/uk/science/article2413310.ece

Posted: 29-01-2010 00:14 Post subject:

Laser fusion test results raise energy hopes
By Jason Palmer
Science and technology reporter, BBC News

A major hurdle to producing fusion energy using lasers has been swept aside, results in a new report show.

The controlled fusion of atoms - creating conditions like those in our Sun - has long been touted as a possible revolutionary energy source.

However, there have been doubts about the use of powerful lasers for fusion energy because the "plasma" they create could interrupt the fusion.

An article in Science showed the plasma is far less a problem than expected.

The report is based on the first experiments from the National Ignition Facility (Nif) in the US that used all 192 of its laser beams.

Along the way, the experiments smashed the record for the highest energy from a laser - by a factor of 20.

Construction of the National Ignition Facility began at Lawrence Livermore National Laboratory in 1997, and was formally completed in May 2008.

The goal, as its name implies, is to harness the power of the largest laser ever built to start "ignition" - effectively a carefully controlled thermonuclear explosion.

It is markedly different from current nuclear power, which operates through splitting atoms - fission - rather than squashing them together in fusion.

Proving that such a lab-based fusion reaction can release more energy than is required to start it - rising above the so-called breakeven point - could herald a new era in large-scale energy production.

In the approach Nif takes, called inertial confinement fusion, the target is a centimetre-scale cylinder of gold called a hohlraum.

It contains a tiny pellet of fuel made from an isotope of hydrogen called deuterium.

During 30 years of the laser fusion debate, one significant potential hurdle to the process has been the "plasma" that the lasers will create in the hohlraum.

The fear has been that the plasma, a roiling soup of charged particles, would interrupt the target's ability to absorb the lasers' energy and funnel it uniformly into the fuel, compressing it and causing ignition.

Siegfried Glenzer, the Nif plasma scientist, led a team to test that theory, smashing records along the way.

"We hit it with 669 kiloJoules - 20 times more than any previous laser facility," Nif's Siegfried Glenzer told BBC News.

That isn't that much total energy; it's about enough to boil a one-litre kettle twice over.

However, the beams delivered their energy in pulses lasting a little more than 10 billionths of a second.

By way of comparison, if that power could be maintained, it would boil the contents of more than 50 Olympic-sized swimming pools in a second.

Crucially, the recent experiments provided proof that the plasma did not reduce the hohlraum's ability to absorb the incident laser light; it absorbed about 95%.

But more than that, Dr Glenzer's team discovered that the plasma can actually be carefully manipulated to increase the uniformity of the compression.

"For the first time ever in the 50-year journey of laser fusion, these laser-plasma interactions have been shown to be less of a problem than predicted, not more," said Mike Dunne, director of the UK's Central Laser Facility and leader of the European laser fusion effort known as HiPER.

"I can't overstate how dramatic a step that is," he told BBC News. "Many people a year ago were saying the project would be dead by now."

Adding momentum to the ignition quest, Lawrence Livermore National Laboratory announced on Wednesday that, since the Science results were first obtained, the pulse energy record had been smashed again.

They now report an energy of one megaJoule on target - 50% higher than the amount reported in Science.

The current calculations show that about 1.2 megaJoules of energy will be enough for ignition, and currently Nif can run as high as 1.8 megaJoules.

Dr Glenzer said that experiments using slightly larger hohlraums with fusion-ready fuel pellets - including a mix of the hydrogen isotopes deuterium as well as tritium - should begin before May, slowly ramping up to the 1.2 megaJoule mark.

"The bottom line is that we can extrapolate those data to the experiments we are planning this year the results show that we will be able to drive the capsule towards ignition," said Dr Glenzer.

Before those experiments can even begin, however, the target chamber must be prepared with shields that can block the copious neutrons that a fusion reaction would produce.

But Dr Glenzer is confident that with everything in place, ignition is on the horizon.

He added, quite simply, "It's going to happen this year."

http://news.bbc.co.uk/1/hi/sci/tech/8485669.stm

Posted: 21-02-2010 12:43 Post subject:

UK plans first nuclear fusion power plant
Jonathan Leake

BRITISH scientists have drawn up plans to build the world’s first nuclear fusion power station. They say it could be pouring electricity into the National Grid within 20 years.

Nuclear fusion, the power that lies at the heart of the sun, offers the prospect of clean, safe, carbon-free power with a minimum of radioactive waste. But despite decades of research the technical problems have seemed insurmountable.

This weekend, however, Research Councils UK (RCUK), which oversees the British government’s spending on science and technology, has said it believes that many of those obstacles are close to being overcome.

It wants to commit Britain to a 20-year research and construction plan that would see a fusion power station in operation around 2030. Didcot in Oxfordshire is among the sites under consideration for the so-called Hiper project.

“The potential of fusion energy to contribute to the future global energy system is sufficiently large that it should be pursued in the UK,” said a report published by RCUK.

It also follows the recent start-up of America’s National Ignition Facility, in California, which has been designed to demonstrate the principle of laser fusion. There, 192 giant lasers have been installed, collectively capable of generating 500 trillion watts — 1,000 times the power of the US national grid — for a fraction of a second.

That energy will be focused on a tiny fuel pellet of frozen hydrogen which, in theory, should be compressed and heated to 100mC — so hot that the atoms within it start to fuse.

“The world is watching and waiting to see what happens at NIF,” said the report, calling this “a seminal moment” in the development of fusion.

Mike Dunne, project co-ordinator for Hiper, agreed. “The NIF laser is performing well — they have already achieved fusion reactions but so far they are putting in much more energy than they are getting out.

“The crucial test will come this autumn when they ramp up the power. In theory they should start generating more power than they put in and if that happens it will be a clear demonstration to the world that laser fusion is ready to be harnessed. So far the signs are very good.”

The Americans designed NIF for a very different purpose from power generation. Its aim is to simulate nuclear explosions so scientists can carry out weapons research. This means that it can trigger only one fusion explosion at a time.

Dunne’s vision for Hiper is to feed a continual stream of fuel pellets into the reactor, blasting them with lasers in rapid succession to generate a constant stream of nuclear fusion explosions.

“The lasers will crush the 2mm pellet to a hundredth of its size in a billionth of a second, making it 10 times hotter than the middle of the sun,” he said.

Under such conditions the hydrogen atoms that make up the fuel are ripped apart, creating a “plasma” of electrons and hydrogen nuclei which collide and interact at high speed.

Some of these collisions result in the nuclei fusing, forming another element called helium and ejecting a neutron, a sub-atomic particle, which hurtles outwards at high speed.

When the neutrons reach the wall of the fusion chamber they pass through it but are absorbed by a blanket of lithium, heating it up. This heat is then captured and used to make steam that can in turn be used to drive a turbine.

The RCUK report, written by a group of independent fusion experts, suggests such a plant would be big enough to generate large amounts of power. “We think the first demonstration should be around 500MW, comparable to a commercial power station,” said Dunne.

Britain has the infrastructure and the workforce needed for nuclear fusion because it hosts the JET fusion facility at Culham in Oxfordshire.

Perhaps one of the greatest challenges for the Hiper team will be creating an international consortium to join Britain on the project, which would cost several billions of pounds.

In theory RCUK can take the decision on such projects without government approval because it has full responsibility for the way it spends its money, but in reality it would need to work closely with ministers.

The Department of Energy and Climate Change said: “This is something that we would look at as long as it is in the framework of a global project.”

http://www.timesonline.co.uk/tol/news/science/article7034945.ece