World's most powerful laser to trigger fusion reaction this year
2010 02 02

From: Telegraph.co.uk


A pivotal step in the march towards fusion power, the ''holy grail'' of sustainable clean energy, could be taken this year.

Scientists in the US are preparing for the dramatic moment when the world's most powerful laser unleashes the nuclear force that lights up the sun and achieves ''ignition''.

At that moment, 192 laser beams housed in a building the size of three football pitches will focus on a target the size of a peppercorn to trigger a self-sustaining fusion reaction.

If all goes according to plan, this could be achieved in October. Although no more than a test of the technology, it could mark the start of a revolution that will change the science and politics of energy for ever.


Inside the target chamber, where scientists will attempt to create an artificial sun.
Photo: Lawrence Livermore National Laboratory

Scientists have spent decades chasing the dream of fusion power, which holds out the promise of producing unlimited amounts of clean energy from hydrogen, the most abundant element in the universe.

Nuclear fusion happens when the nuclei of atoms are driven together so hard that they fuse to form a heavier particle. A self-sustaining chain reaction occurs as more atomic nuclei collide, releasing huge amounts of energy in the process.

Stars are driven by nuclear fusion, as is the immense destructive power of the hydrogen bomb. But no one has yet managed to contain and sustain a fusion reaction under controlled conditions.

The biggest problem facing fusion scientists is how to generate the enormous temperatures and pressures necessary for long enough in a confined space.

Self-sustaining fusion requires conditions more extreme than at the centre of the Sun, with temperatures of around 100 million centigrade.

At the new National Ignition Facility (NIF) at Lawrence Livermore National Laboratory in California, scientists are closer to overcoming this hurdle than anyone has been before.

The 10-storey high NIF is a £2 billion sledgehammer built to crack a nut.
Opened last year, the facility houses an array of optical and electronic devices designed to split a laser 192 ways and boost the combined energy of the beams to 1.8 megajoules.

At its heart the ''nut'' is a tiny beryllium capsule the size of a peppercorn, designed to hold a dash of nuclear fuel in the form of deuterium and tritium.

Both are isotopes, or different atomic versions, of hydrogen.
The aim is to focus the laser beams on the capsule and blast it with a pulse of energy that causes the fuel to implode in an instant, reaching temperatures and pressures greater than those at the centre of the Sun.
Crushed together, the deuterium and tritium nuclei will fuse, releasing a flash of energy. If the experiment is a success, more energy will be generated than was pumped into the capsule in the first place.

A report of the latest progress at the NIF published last week in the journal Science shows that the scientists are on target.

Dr Siegfried Glenzer and colleagues described the first experiments in which all 192 of the lasers were tested on targets empty of fuel, achieving a beam energy of about 40% the NIF's maximum.

A major problem that had to be overcome was getting the capsule to implode evenly.

This was done by encasing it in a gold cylinder called a hohlraum, pierced by holes through which the laser beams were shone.

''We're doing the real thing, and it's going better than expected,'' said Dr Glenzer, quoted in a Science news article.

The facility's ''ignition campaign'', leading to the first attempt to produce a self-sustaining fusion reaction is due to start in earnest in May.

A decision will be made in July on whether or not to push ahead with full-scale fusion experiments paving the way to ignition in October.

British expert Professor Mike Dunne, director of the Central Laser Facility at the Rutherford Appleton Laboratory in Didcot, Oxfordshire, said: ''It's come up better than anyone thought. They're ahead of the curve predicted.''

Article from: Telegraph.co.uk



Related Articles
Fusion power - Wikipedia
Scientists hope to tap energy of the sun
The nuclear reactor that could clean up
Nuclear fusion energy project could lead to limitless clean electricity
Scientists plan to ignite tiny man-made star


Latest News from our Front Page

Norway Joins the Race to Develop Killer Robots
2014 10 24
Norway is a large exporter of weapons, which makes the resolution of the debate about creating killer robots an important issue for everyone.  One could debate the overall merits or failings of robotic systems, but an area that clearly has become a point for concern on all sides is the emergence of "killer robots." According to robotics pioneer, David Hanson, ...
Gene That Once Aided Survival in the Arctic Found to Have Negative Impact on Health Today
2014 10 23
In individuals living in the Arctic, researchers have discovered a gene variant that arose thousands of years ago and most likely provided an evolutionary advantage for processing high-fat diets or for surviving in a cold environment; however, the variant also seems to increase the risk of hypoglycemia, or low blood sugar, and infant mortality in today’s northern populations. {snip} “Our work ...
The Ebola hoax: questions, answers, and the false belief in the “One It”
2014 10 23
“The Reality Manufacturing Company doesn’t just sell ‘fake paintings’ that are easy to spot. No. They also sell images that are geared to mesh with people’s deeply held instincts and thereby produce rigid false beliefs. People are sure that if they gave up such beliefs, their world would fall apart and blow away in the wind.” ...
New Controversial Theory Suggests "Hobbits" Were Not Human - Who Were These Mysterious Beings?
2014 10 23
The origin of the Hobbit species remains a challenging subject to scientists. The Hobbit’s discovery confirmed the view that the Earth was once populated by many species of human, but new research the Hobbit’s were not human at all! So, who were these mysterious beings? Where did they come from? The idea that our species, Homo sapiens, was the only species of human on ...
Right into enemy hands? ISIS shows off new weapons allegedly airdropped by US (VIDEO)
2014 10 23
Islamic State has published a new video in which a jihadist shows off brand-new American hardware, which was purportedly intended for the Kurds they are fighting in the Syrian border town of Kobani. The undated video, posted by the unofficial IS mouthpiece “a3maq news”, sees a jihadist showing several boxes of munitions with English-language markings, with a parachute spread out on ...
More News »