Archive for the ‘nuclear fusion’ Category

Fusion nuclear reactors? Let’s bust the hype!

May 18, 2017

These impediments—together with colossal capital outlay and several additional disadvantages shared with fission reactors—will make fusion reactors more demanding to construct and operate, or reach economic practicality, than any other type of electrical energy generator.

The harsh realities of fusion belie the claims of its proponents of “unlimited, clean, safe and cheap energy.” Terrestrial fusion energy is not the ideal energy source extolled by its boosters, but to the contrary: Its something to be shunned.

Fusion reactors: Not what they’re cracked up to be http://thebulletin.org/fusion-reactors-not-what-they%E2%80%99re-cracked-be10699  Daniel Jassby, 19 Apr 17 Daniel Jassby was a principal research physicist at the Princeton Plasma Physics Lab until 1999. For 25 years he worked in areas of plasma physics and neutron production related to fusion energy research and development. He holds a PhD in astrophysical sciences from Princeton University.

Fusion reactors have long been touted as the “perfect”energy source. Proponents claim that when useful commercial fusion reactors are developed, they would produce vast amounts of energy with little radioactive waste, forming little or no plutonium byproducts that could be used for nuclear weapons. These pro-fusion advocates also say that fusion reactors would be incapable of generating the dangerous runaway chain reactions that lead to a meltdown—all drawbacks to the current fission schemes in nuclear power plants.

And, a fusion-powered nuclear reactor would have the enormous benefit of producing energy without emitting any carbon to warm up our planet’s atmosphere.

But there is a hitch: While it is, relatively speaking, rather straightforward to split an atom to produce energy (which is what happens in fission), it is a “grand scientific challenge” to fuse two hydrogen nuclei together to create helium isotopes (as occurs in fusion). Our sun constantly does fusion reactions all the time, burning ordinary hydrogen at enormous densities and temperatures. But to replicate that process of fusion here on Earth—where we don’t have the intense pressure created by the gravity of the sun’s core—we would need a temperature of at least 100 million degrees Celsius, or about six times hotter than the sun. In experiments to date the energy input required to produce the temperatures and pressures that enable significant fusion reactions in hydrogen isotopes has far exceeded the fusion energy generated.

But through the use of promising fusion technologies such as magnetic confinement and laser-based inertial confinement, humanity is moving much closer to getting around that problem and achieving that breakthrough moment when the amount of energy coming out of a fusion reactor will sustainably exceed the amount going in, producing net energy. Collaborative, multinational physics project in this area include the International Thermonuclear Experimental Reactor (ITER) joint fusion experiment in France which broke ground for its first support structures in 2010, with the first experiments on its fusion machine, or tokamak, expected to begin in 2025.

As we move closer to our goal, however, it is time to ask: Is fusion really a “perfect”energy source? After having worked on nuclear fusion experiments for 25 years at thePrinceton Plasma Physics Lab, I began to look at the fusion enterprise more dispassionately in my retirement. I concluded that a fusion reactor would be far from perfect, and in some ways close to the opposite.

Scaling down the sun.  (more…)

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Nuclear fusion research in China – still decades away from application

March 20, 2016
Chinese Fusion Test Hits A Milestone By Creating 90 Million °F For 102 Seconds http://www.techworm.net/2016/02/chinese-fusion-test-hits-milestone-creating-90-million-f-102-seconds.html  BY  ON FEBRUARY 9, 2016 

Chinese scientists create record by hitting 90 Million °F For 102 Seconds which is three times hotter than the Sun

Scientists in China were able to heat plasma to three times the temperature of the core of our sun using nuclear fusion – a temperature of 90 million °F – for an impressive 102 seconds, as they continued their search to derive energy from nuclear fusion.

They have surpassed the nuclear fusion experimental device referred to as the Wendelstein 7-X (W7-X) stellerator developed by a team of German researchers from the Max Planck Institute that managed to heat hydrogen gas to 80 million degrees Celsius, and sustain a cloud of hydrogen plasma for a quarter of a second.

According to a statement on the institute’s website last Wednesday, the experiment was conducted on a magnetic fusion reactor at the Institute of Physical Science in Hefei, capital of Jiangsu province.

The experiments were carried out in a donut-shaped reactor, officially known as the Experimental Advanced Superconducting Tokamak (EAST). The reactor was able to heat a hydrogen gas – a hot ionised gas called plasma – to about 50 million Kelvins (49.999 million degrees Celsius). The interior of our sun is calculated to be around 15 million Kelvins.

The plasma can be contained by careful control of intense magnetic fields in a tight ring by running through the center of the donut’s circular cross section. In other words, the walls of the structure are never directly exposed to the high temperatures of the plasma.

For the long term goal of such fusion reactors, it is very necessary to make sure that those temperatures can be sustained for long period of time, as a huge input of energy is required to get them started. But, if they end up stopping too soon, the reaction is net negative in energy terms. Such high energies cause great instabilities making it difficult to confine them, as controlling such intense heat is tough. Therefore, it is a positive step indeed for running an experiment at such temperatures for 102 seconds.

It’s not the hottest temperature ever created on Earth. So far, the hottest temperature to have been created artificially in the lab remains that reached by the gargantuan Large Hadron Collider (LHC) at CERN, which managed to achieve temperatures of 4 trillion degrees Celsius back in 2012. However, those conditions last for the sheer flicker of time, which is inadequate for creating energy.

The ultimate goal of China’s team is to hit 100 million degrees Celsius now, and sustain the resulting hydrogen plasma for over 1,000 seconds, or 17 minutes. In the meantime, now that their ‘proof of concept’ experiment is out of the way, the German team says it could possibly sustain its plasma for as long as 30 minutes.

However, most scientists who are in agreement advocate that the long-yet-intense burn required for fusion needs to be around 180 million °F, which means we are likely decades away from actually connecting nuclear fusion to solve humanity’s energy problems.

Nuclear fusion reactor launched in Germany

January 4, 2016

Germany launches world’s largest nuclear fusion reactor  The rocky road to nuclear fusion power, DW, 18 Dec 15   Innovative designs using modern superconductors are supposed to bring us nuclear fusion power plants soon – some optimists say. Fusion experts predict, however, that a practical application will take many more decades. Nuclear fusion is considered a potential energy source of the future. It’s clean nuclear energy. But what is it, exactly and why is it so difficult to generate? Let’s start with the difference between classical nuclear fission and nuclear fusion.

Nuclear fission means that radioactive isotopes, like uranium or plutonium are being split up and turned into other highly radioactive isotopes that then have to be deposited or reprocessed.

Nuclear fusion means that two isotopes of hydrogen – called deuterium and tritium – merge together – they “fuse.” And that leaves behind only non-poisonous helium and one single neutron, but no nuclear waste.

Huge amounts of energy caught in a plasma

Nuclear fusion takes place in the sun for example – or in a hydrogen bomb – and that’s the big challenge for engineers – how do you control the high energy fusion process in a power plant?

That’s what scientists have been working on since the 1960s. One model-fusion-reactor called Wendelstein 7-X has just started operating in the northern German town of Greifswald. It is not designed to generate a nuclear fusion reaction yet – so far it’s just a specific reactor design that’s being tested.

What all fusion reactors have in common is a ring-shaped form. The idea behind it is to take powerful electromagnets and create a strong electromagnetic field, which is shaped somewhat like an inflated bicycle tube.

That electromagnetic field must be so dense that when it is being heated by a microwave oven to about one million degrees centigrade, a plasma will emerge in the very center of the ring. And that plasma can then be ignited to start the nuclear fusion process.

Research reactors show what’s possible

In Europe, two prominent fusion experiments are under way. One is Wendelstein 7-X, which just generated its first helium plasma last week – albeit without actually going into nuclear fusion. The other one is ITER – a huge experimental project in southern France, which is still under construction and won’t be ready to run before 2023.

ITER is supposed to do real nuclear fusion – but only for short periods of time, certainly not for any longer than 60 minutes. And ITER is just one of many steps towards turning the idea of nuclear fusion into a practical application.

Are smaller, alternative designs feasible?………

Hot, hot, hot

The heat is also problematic. In the core of the nuclear-fusion plasma, the temperature would be around 150 million centigrade. This extreme heat stays put – right there in the center of the plasma. But even around it, it still gets seriously hot – 500 to 700 degrees at the breeding blanket – which is the inner layer of the metal tube that contains the plasma and which will serve to “breed” the tritium that is needed for the fusion reaction.

Even more problematic is the so called “power-exhaust.” That is the part of the system, where the used-up fuel from the fusion process is being extracted – mostly helium. The first metal components hit by hot gases are called the “diverter.” It can get hotter than 2,000 degrees centigrade.

The engineers are trying to use the metal tungsten, used in old-fashioned light bulbs – to withstand such temperatures. They have a melting point of around 3,000 degrees. But there are limits.

“In the case of ITER we can do it, because the heat is not there constantly. Only one to three percent of the time, ITER will eventually be running.” Hesch says. “But that is not an option for a power plant, which has to run 24/7. And if someone pretends to build a smaller reactor with the same power as ITER, I can definitely say – there is no solution for that diverter-problem.”

Several decades to build a real power plant

Nonetheless Hesch is optimistic that the development of nuclear fusion power reactors will go ahead – but not quite as fast as some of the industry optimists predict.

“With ITER we want to show that fusion can actually deliver more energy than we have to put into it to heat the plasma. The next step would be to build an entirely new fusion demonstrator power plant, which will actually generate electricity.”

The engineers are already working on the designs now. They will have to learn lessons from ITER, which is scheduled to start operating in 2023. Taking the necessary time for design, planning and construction into account, it looks very unlikely the first nuclear-fusion power plant will be up and running much before the middle of the century. http://www.dw.com/en/the-rocky-road-to-nuclear-fusion-power/a-18927630

A costly pipe dream – Nuclear Fusion

January 4, 2016

The challenges that make fusion potentially permanently decades away have been identified as threefold. The first is for the reactor to generate more energy than it takes to produce it. The second is for the reactor to produce more energy than the facility as a whole uses to make it. And the third is to actually make electricity in this fashion without going completely broke.

The False Promise of Nuclear Fusion http://www.counterpunch.org/2015/12/11/the-false-promise-of-nuclear-fusion/ by LINDA PENTZ GUNTER There have been some pretty radioactive climate change ideas making the rounds at the COP21 talks in Paris. Team Hansen’s wildly unrealistic notion of switching on 61 new nuclear reactors a year was taking the cake until an even fruitier one reared its familiar head: the nuclear chimera known as ITER.

ITER was originally called the International Thermonuclear Experimental Reactor, with ‘experimental’ being the operative word in that lofty title. Which is perhaps why today they refer to it only by acronym (apparently the word ‘thermonuclear’ also had some rather explosive connotations.) The official website equates ITER with its coincidental Latin meaning, ‘The Way’.

ITER was initiated in 1985 by then presidents Reagan and Gorbachev. The multi-nation project included not only the United States and the already crumbling Soviet Union, but the European Union and Japan. Today there are 35 countries in the partnership.

If it ever gets completed and actually works, ITER will be a fusion reactor known as a Tokomak. Fusion is the physicists’ wet dream, and they’ve been hallucinating about ITER for precisely three decades and Tokomaks and fusion itself for even longer.

ITER itself isn’t even the final step to electricity-producing fusion power plants. Its purpose is in “preparing the way for the fusion power plants of tomorrow.” A tomorrow that is heralded as ten years away, decade after decade. (more…)

Nuclear fusion? it’s a white elephant

November 19, 2015

Another Fusion White Elephant Sighted in Germany http://helian.net/blog/October 27th, 2015  Helian  According to an article that just appeared in Science magazine, scientists in Germany have completed building a stellarator by the name of Wendelstein 7-X (W7-X), and are seeking regulatory permission to turn the facility on in November.  If you can’t get past the Science paywall, here’s an article in the popular media with some links.  Like the much bigger ITER facility now under construction at Cadarache in France, W7-X is a magnetic fusion device.  In other words, its goal is to confine a plasma of heavy hydrogen isotopes at temperatures much hotter than the center of the sun with powerful magnetic fields in order to get them to fuse, releasing energy in the process.  There are significant differences between stellarators and the tokamak design used for ITER, but in both approaches the idea is to hold the plasma in place long enough to get significantly more fusion energy out than was necessary to confine and heat the plasma.  Both approaches are probably scientifically feasible.  Both are also white elephants, and a waste of scarce research dollars.

The problem is that both designs have an Achilles heel.  Its name is tritium.  Tritium is a heavy isotope of hydrogen with a nucleus containing a proton and two neutrons instead of the usual lone proton.  Fusion reactions between tritium and deuterium, another heavy isotope of hydrogen with a single neutron in addition to the usual proton, begin to occur fast enough to be attractive as an energy source at plasma temperatures and densities much less than would be necessary for any alternative reaction.  The deuterium-tritium, or DT, reaction will remain the only feasible one for both stellarator and tokamak fusion reactors for the foreseeable future.  Unfortunately, tritium occurs in nature in only tiny trace amounts.

The question is, then, where do you get the tritium fuel to keep the fusion reactions going?  Well, in addition to a helium nucleus, the DT fusion reaction produces a fast neutron.  These can react with lithium to produce tritium.  If a lithium-containing blanket could be built surrounding the reaction chamber in such a way as to avoid interfering with the magnetic fields, and yet thick enough and close enough to capture enough of the neutrons, then it should be possible to generate enough tritium to replace that burned up in the fusion process.  It sounds complicated but, again, it appears to be at least scientifically feasible.  However, it is by no means as certain that it is economically feasible.

Consider what we’re dealing with here.  Tritium is an extremely slippery material that can pass right through walls of some types of metal.  It is also highly radioactive, with a half-life of about 12.3 years.  It will be necessary to find some way to efficiently extract it from the lithium blanket, allowing none of it to leak into the surrounding environment.  If any of it gets away, it will be easily detectable.  The neighbors are sure to complain and, probably, lawyer up.  Again, all this might be doable.  The problem is that it will never be doable at a low enough cost to make fusion reactor designs based on these approaches even remotely economically competitive with the non-fossil alternative sources of energy that will be available for, at the very least, the next several centuries.

What’s that?  Reactor design studies by large and prestigious universities and corporations have all come to the conclusion that these magnetic fusion beasts will be able to produce electricity at least as cheaply as the competition?  I don’t think so.  I’ve participated in just such a government-funded study, conducted by a major corporation as prime contractor, with several other prominent universities and corporations participating as subcontractors.  I’m familiar with the methodology used in several others.  In general, it’s possible to make the cost electricity come out at whatever figure you choose, within reason, using the most approved methods and the most sound project management and financial software.  If the government is funding the work, it can be safely assumed that they don’t want to hear something like, “Fuggedaboudit, this thing will be way too expensive to build and run.”  That would make the office that funded the work look silly, and the fusion researchers involved in the design look like welfare queens in white coats.  The “right” cost numbers will always come out of these studies in the end.

I submit that a better way to come up with a cost estimate is to use a little common sense.  Do you really think that a commercial power company will be able to master the intricacies of tritium production and extraction from the vicinity of a highly radioactive reaction chamber at anywhere near the cost of, say, wind and solar combined with next generation nuclear reactors for baseload power?  If you do, you’re a great deal more optimistic than me.  W7-X cost a billion euros.  ITER is slated to cost 13 billion, and will likely come in at well over that.  With research money hard to come by in Europe for much worthier projects, throwing amounts like that down a rat hole doesn’t seem like a good plan.

All this may come as a disappointment to fusion enthusiasts.  On the other hand, you may want to consider the fact that, if fusion had been easy, we would probably have managed to blow ourselves up with pure fusion weapons by now.  Beyond that, you never know when some obscure genius might succeed in pulling a rabbit out of their hat in the form of some novel confinement scheme.  Several companies claim they have sure-fire approaches that are so good they will be able to dispense with tritium entirely in favor of more plentiful, naturally occurring isotopes.  See, for example, herehere, andhere, and the summary at the Next Big Future website.  I’m not optimistic about any of them, either, but you never know.

Nuclear fusion needs more energy to produce than it can make

February 2, 2015

Why We Will Never Make A Nuclear Fusion Reactor As Good As The Sun, Business Insider,  JESSICA ORWIG OCT 17 2014 “…………..combine four hydrogen atoms and you get a burst of energy that can destroy entire islands and did on Nov. 1, 1952. That day the US tested the first hydrogen bomb on the now-nonexistent Pacific island, Elugelab.……… Clean, limitless energy is the real holy grail. Combine that desire with the awesome power we first saw with the< H-bomb, and we’ve been dreaming of a way to harness nuclear fusion of the sun as a source of clean, endless energy.

But so far, only Hollywood has managed…….. The amount of energy we need to produce the conditions for nuclear fusion is more than the energy we get out. And we’ve been coming up short for decades with little signs of improvement, according to Charles Seife,author of the book “Sun in a Bottle: The Strange History of Fusion and the Science of Wishful Thinking“who has written about the turtle-paced race for nuclear fusion for Slate.
Unfortunately for us, it is incredibly difficult to fuse hydrogen atoms together. It takes extreme pressure and heat, something that the sun’s strong gravitational force does naturally in its core. But we don’t have access to this kind of gravity here on our comparatively tiny Earth, and the only way to manufacture it is to expend a ton of energy to create it.
For about the last 70 years, we’ve slowly developed ways of producing the extreme pressure and heat necessary for nuclear fusion. Today, the most promising methods use containment vessels called tokamaks that can sustain hot plasmas that produce nuclear fusion but require lots of energy and space to function. The other way is using powerful lasers to fuse hydrogen atoms together.

Both of these methods, however, still have a long way to go despite what you might read from the occasional headlines on the latest breakthroughs in new nuclear fusion technology………http://www.businessinsider.com.au/we-will-never-have-sun-like-nuclear-fusion-2014-10

Would nuclear fusion really be safe?

December 29, 2013

the first wall”: any nuclear fusion facilities must be fitted with an internal container made up by a “first wall” that faces the space where the reaction takes place.

This wall will be exposed to neutronic radiation. It won’t take long for it to become radioactive and begin to erode. In time, it will have to be replaced by another wall if the fusion reactor is to remain in operation.

Where will the discarded containers end up? These “first walls” will be loaded with radioactivity. As fusion technology develops, this can become a problem.

nuclear-fusion-pie-SmNuclear Fusion: Is it as Safe as We Think? Dmitri Prieto http://www.havanatimes.org/?p=99809  4 Nov 13
HAVANA TIMES — It seems to me that we are not sufficiently aware of the risks surrounding a new, emerging technology. Producing energy through the fusion of light nuclei (such as deuterium and tritium, which are heavy, radioactive isotopes of hydrogen) is the dream of many physicists and technologists.

This is the process which takes place inside the sun, the stars and hydrogen bombs. The aim is to “domesticate” the thermonuclear reaction so that, on the one hand, it does not produce an explosion (like the 50-megaton hydrogen bomb detonated by the Soviets in the Arctic in 1961), and, on the other, the process stabilizes at a temperature in which the atomic nuclei can fuse and generate energy.

No fusion thermonuclear plant yet exists.   Existing complexes are fission plants. I am referring to those that work on uranium and plutonium (like the Chernobyl and Fukushima nuclear power plants).

Since I was a child, I, the son of electrical engineers and physics lovers, have been hearing that we will “soon” see the first fusion reactor. I’ve read stories about complex Tokamak machines that use a magnetic field to control the ultra-hot plasma where the thermonuclear reaction is supposed to take place, and about reactors that heat up and weld radioactive isotopes with lasers.

In the 80s, there were even those who claimed they could achieve “cold fusion”, something which turned out to be a hoax.

I was about to get bored from the long wait (I’ve had plenty of people tell me that the “sun on earth” is just “around the corner”) when, this past October 18, Cuba’s Granma newspaper published an article quoting a BBC piece (Paul Rincon’s “Nuclear fusion milestone passed at US lab”) which reported that, under strictly controlled conditions and using 192 lasers, scientists at California’s National Ignition Facility managed to have a hydrogen pellet produce more energy by nuclear fusion than that supplied by the lasers.

That is to say, for the first time in history, controlled fusion has become a fact. It’s been proven: a facility that produces energy through the fusion of hydrogen nuclei can be constructed.

Of course, we’re not talking about a functioning thermonuclear plant, but about the possibility, in principle, of building one in the future. In this connection, Granma repeats what has become a commonplace for those who write (or read) about the study of nuclear fusion:

“They call it ‘The Holy Grail’ of energy, for it is clean, cheaper and practically inexhaustible…for it can meet the world’s energy needs without the threat of nuclear proliferation or environmental damage. [While] fission produces highly destructive and long-lasting residues that are difficult to eliminate, the residue produced by fusion is helium, a harmless and economically valuable gas.”

From this, we get the idea that fusion is so good that, in addition to solving humanity’s energy problems once and for all, it can be used to produce helium, a gas with which balloons at sweet-fifteen birthday parties can be filled up. It all sounds very clean and safe.

I feel, however, that we are (once again) giving in to dangerous hyperbole. Nuclear fusion produces neutrons.

Neutrons, as their name indicates, are neutral particles. As such, it isn’t hard for them to interact with positively-charged atomic nuclei. Neutronic radiation, thus, is capable of transforming a given nucleus into a heavier isotope, which tends to be radioactive.

This leads us to the problem of “the first wall”: any nuclear fusion facilities must be fitted with an internal container made up by a “first wall” that faces the space where the reaction takes place.

This wall will be exposed to neutronic radiation. It won’t take long for it to become radioactive and begin to erode. In time, it will have to be replaced by another wall if the fusion reactor is to remain in operation.

Where will the discarded containers end up? These “first walls” will be loaded with radioactivity. As fusion technology develops, this can become a problem.

Scientists may claim that the levels of radioactivity produced are low and the risks minor when compared to the advantages of this energy generating technology. But they said the same thing when fission reactors started to be used, and we know what happened later. I wonder if scientists have any concrete proposal in this regard

– See more at: http://www.havanatimes.org/?p=99809#sthash.McLamxb1.dpuf

Nuclear fusion – nowhere near even a feasibility study

November 4, 2012

Nuclear Fusion Project Struggles to Put the Pieces Together Scientific America, 27 Oct 12,Contracting woes may cause further delays for $19.4-billion ITER, a project designed to show the feasibility of nuclear fusion as a power source

By Geoff Brumfiel and Nature magazine The world’s largest scientific project is threatened with further delays, as agencies struggle to complete the design and sign contracts worth hundred of millions of euros with industrial partners, Nature has learned.

ITER is a massive project designed to show the feasibility of nuclear fusion as a power source. The device consists of a doughnut-shaped reactor called a tokamak, wrapped in superconducting magnets that squeeze and heat a plasma of hydrogen isotopes to the point of fusion. The result should be something that no experiment to date has been able to achieve: the controlled release of ten times more energy than is consumed.

That’s the dream. But so far, ITER has been consuming mostly money and time. (more…)

The nuclear fusion dream – just as elusive as ever

November 4, 2012

Fusion: Maybe Less Than 30 Years, But This Year Unlikely Bill Chameides Dean, Duke University’s Nicholas School of the Environment, August 2012 No ignition at the U.S. National Ignition Facility , home to the world’s largest laser….. Scientists have been thinking about how to bring this game changer into the energy game for decades. (See fusion/fission timeline .) As far back as 1946, two British scientists — Sir George Paget Thomson and Moses Blackman — filed the first patent for a fusion power plant .

But there have been a couple of hold-ups . To get a fusion reaction started, you need to slam the hydrogen atoms together really, really hard and that requires a lot of energy. (In a hydrogen bomb, the fusion reaction gets ignited by an atomic bomb, using fission. Not exactly the preferred method for your local fusion power plant.)

Even trickier is controlling the fusion reaction. It’s one thing to make a fusion bomb, it’s a lot harder to get the reaction going and keep it under control in a way that the amount of energy extracted is larger than that expended to initiate and manage the reaction.

Over the almost 70-year pursuit of the fusionary holy grail, it’s been fairly common for scientists working on the problem to say that they’re about 30 years away from achieving a power plant based on fusion. (See here  and here .) The problem has been that while time has marched on, the 30-year horizon has remained fixed. Suffice to say it has proven to be a very tough problem…. http://www.huffingtonpost.com/bill-chameides/fusion-maybe-less-than-30_b_1949573.html

An unaffordable pipedream – nuclear fusion

April 28, 2012

“Fusion will never be a practical source because it requires vast resources and technical capital”

The Tantalizing Promise And Peril Of Nuclear Fusion, Forbes, 15 April 12 “…..To be clear, fusion is different from fission, which is how today’s nuclear reactor’s produce energy. Fission splits atoms apart whereas fusion combines them — a process that thus far consumes more energy than it generates. The aim, though, is to heat the hydrogen gas to more than 100 million degrees Celsius so that the atoms will bond instead of bouncing off each another. ….
“All ITER members consider this spending a good investment. What is at stake is a new source of energy on earth, which will be safe, with almost limitless fuel and environmentally responsible.”
But others are more tempered, if not outright cynical about fusion technology. The central question is whether the process can ever yield enough heat to fuse permanently those atoms that are needed to commercialize such power…..

Here, the argument breaks down two ways: the knowledge and the expense. The National Academy of Sciences is saying that the field is still in its “early stages” and that critical challenges remain. Then there’s the European Parliament’s green movement, which calls ITER funding not just wrongheaded in the aftermath of the Japan’s Fukushima but also a “ticking budgetary time bomb.”

“Fusion will never be a practical source because it requires vast resources and technical capital,” adds John Kutsch, executive director of the ThoriumEnergy Alliance, in a talk with this reporter. “On paper, it looks awesome but when you get down to practicalities, it is beyond our capabilities.”…. http://www.forbes.com/sites/kensilverstein/2012/04/15/nuclears-strongest-potential-weapon-fusion/