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Alias
QUOTE
An Australian-led team of scientists may have found away of creating a cheap and abundant source of clean energy through nuclear fusion.

The process could generate no radioactivity and produce little pollution.

The scientists have used computer models to simulate nuclear fusion without the extreme temperatures currently needed for other fusion methods.

Emeritus Professor Heinrich Hora, of the Department of Theoretical Physics at the University of New South Wales, is leading the research effort, and says the process relies on a new generation of extremely powerful and very fast lasers being developed.

"The key is a very carefully controlled extremely short laser pulse essential for ignition. The pulse would ignite a fuel made of ordinary hydrogen and boron-11," Professor Hora said.

"The idea of a hydrogen and boron fusion reaction is interesting because it wouldn't cause neutron production. Neutrons are a problem because they generate radioactivity."

The team's findings appear in the journal Energy and Environmental Science.

Professor Hora says his team was originally developing computer models using next generation lasers to duplicate the work being done at the new $4.34 billion National Ignition Facility at the Lawrence Livermore National Laboratory in the United States.

The US scientists are developing what is currently the world's largest laser to ignite highly compressed spheres of deuterium-tritium fuel in a nuclear fusion reaction.

Fast and furious


The laser can produce a pulse of a few billionths of a second duration which produces 500 times more power than all US power stations combined.

Professor Hora's team originally rejected the idea of a hydrogen-boron fuel for their simulations "because the higher temperatures and compression needed made it 100,000 times more difficult than the Lawrence Livermore approach, making it just about impossible".

"But when we ran computer simulations using these next generation petawatt [quadrillion watt] strength lasers with a hydrogen-boron fuel, we were shocked to find that it's only 10 times more difficult than deuterium-tritium," he said.

"It makes this all within the reach of current technology in a relatively short time. In fact these types of lasers are already in early testing at the Los Alamos National Laboratory."

Professor Hora says the key is to ensure the laser pulse is "extremely clean", lasting no more than a millionth of a millionth of a second.

"This allows conversion of optical energy to mechanical energy without heating," he says.

Professor Hora says the hydrogen-boron fuel has a numberof advantages over deuterium-tritium.

"It would be largely free of radioactive emissions producing less radiation than that emitted by current power stations that burn coal, which contains trace amounts of uranium," he says.

According to Professor Hora, hydrogen and boron are plentiful and readily accessible, and the waste product of ignition would be clean helium gas.

"The hydrogen-boron fuel would not have to be compressed. This means it needs far less energy to start the ignition," he said.

But Professor Hora warns the study only demonstrates the potential of the new process and much work needs to be done to demonstrate it in practice.
http://www.abc.net.au/news/stories/2010/04/06/2865472.htm

beefJeRKy
Sounds like an interesting prospect. I certainly hope they'll actually make nuclear fusion achievable. Then hopefully the need to fight for energy will be less clear cut.
R3ven
Fusion is already possible, how do you think any element after uranium(and two of them before it as well) were made?

And no they are not conceptual, after 14 year of back up research the 112 element, named Copernicium, was accepted to the Periodic Table in February.

http://www.sciencenews.org/view/generic/id...mic_heavyweight
Alias
If you read the article you would realise this isn't your ordinary fusion.
Pickysaurus
Isn't this basically cold fusion?
Waris
QUOTE (Pickysaurus @ 7 Apr 2010, 1:16) *
Isn't this basically cold fusion?

It is, but scientists would avoid associating it with the term 'cold fusion' and the bad rep that comes with said term.
Shock
So technically this is rather skipping the heat factor required to overcome the Vanderwaals forces and just give a 'mechanical' push through it by using lasers and lasers alone?

I wonder how that theory works. Probably too complicated to understand but I'm still interested.

The fusion will have to sustain itself, which means it needs to power the laser and has to power electrolysis to generate your Hydrogen. I'm sure there is enough potential power but I want to read in quantities before I draw my conclusions.
Shiro
QUOTE (Shock @ 7 Apr 2010, 15:43) *
So technically this is rather skipping the heat factor required to overcome the Vanderwaals forces and just give a 'mechanical' push through it by using lasers and lasers alone?

Maybe because the lasers are stronger than the Vanderwaals forces? I have no idea either tongue.gif

Anyway, I guess this fusion would produce Carbon, no?
walkingGhost
QUOTE
Isn't this basically cold fusion?

It isn't. Cold fusion is supposed to occur at roomtemperature, but those boron/hydrogen- pellets sure ain't at roomtemperature anymore after being exposed to an ultra-high-powered laser- beam.

QUOTE
So technically this is rather skipping the heat factor required to overcome the Vanderwaals forces and just give a 'mechanical' push through it by using lasers and lasers alone?

Not exactly (the heat is still there): the fuel-pellets get hit with the laser-beam from all directions, making the outer layer of the pellet explode- this 'explosion' compresses the material enough for nuclear fusion to occur. The fusion itself is NOT selfsustaining- it lasts only for an extremely short period of time; commercial plants would thus need to operate in periodical bursts (a bit like a combustion engine). The energy is emitted in form of alpha- radiation (ionized helium-atoms travelling at high speed).

The whole process is known as inertial confinement fusion (wiki), and not exactly new (there have been experiments since the 1970's).
The new boron-hydrogen fuel is very interesting, though- neutron-emission is the nastiest form of nuclear radiation (neutrons, having no electrical charge, are diffcult to stop and can 'activate' otherwise non-radioactive materials); would be nice to get rid of it.
ComeOn
Neat-o. biggrin.gif
Shock
QUOTE (walkingGhost @ 7 Apr 2010, 19:58) *
It isn't. Cold fusion is supposed to occur at roomtemperature, but those boron/hydrogen- pellets sure ain't at roomtemperature anymore after being exposed to an ultra-high-powered laser- beam.


Not exactly (the heat is still there): the fuel-pellets get hit with the laser-beam from all directions, making the outer layer of the pellet explode- this 'explosion' compresses the material enough for nuclear fusion to occur. The fusion itself is NOT selfsustaining- it lasts only for an extremely short period of time; commercial plants would thus need to operate in periodical bursts (a bit like a combustion engine). The energy is emitted in form of alpha- radiation (ionized helium-atoms travelling at high speed).

The whole process is known as inertial confinement fusion (wiki), and not exactly new (there have been experiments since the 1970's).
The new boron-hydrogen fuel is very interesting, though- neutron-emission is the nastiest form of nuclear radiation (neutrons, having no electrical charge, are diffcult to stop and can 'activate' otherwise non-radioactive materials); would be nice to get rid of it.

Well with self-sustaining I don't mean a chain reaction, but more in the sense that the alpha radiation can supply enough energy to power the whole process, so in a macroscopic view of sustainability.

This is of course, all pretty straight forward, but its a big hike with the conventional big large magnetic heat fusion reactors. With those there is hardly enough power to power the process itself, and then you haven't even calculated in the power required to produce deuterium, so its ineffective overall. Inside the sun this all is powered by gravity, which we cannot utilise in such a way.

Boron-hydrogen fusion may be cool, but do take into account boron isn't a very common element, representing around 0.001 percent of the earth crust.
walkingGhost
I've also doubts that this laser-powered fusion will EVER crack the break-even point; IMO the article is overly optimistic on that.

The polywell (wiki) is another 'exotic' approach (but simple in design), and could get results (net- energy gain) in 2020 already... But sadly it's one of those maybe it'll work, maybe it won't- thingies- we'll just have to wait and see.

Good old Tokamak still seems to be the most promising technologie, but the first plant won't be running before 2040 (DEMO), and there are plenty of opportunities for further delay...
Shock
The big difference is that you don't need superpowered magnets and you only need localized reactions. I would like to see the difference in energy output between deuterium-tritium and hydrogen-boron fusions.

Fusion power has a great potential to cross break-even, if you manage to lower the amount of energy required for input. However, I'm not a physicist, but Gravity in the Sun is in a sense an unlimited source of energy. Removing that one will make it very hard to generate fusion.
IonCharge
QUOTE (Laser Missile Defender)
Who needs coal when we have lasers?


Seems pretty cool smile.gif Infact I might use this idea for my book... seems good
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