Nuclear energy: nuclear fusion produces energy for the first time - Times Online

In the laboratory, U.S. researchers have by nuclear fusion produces as much energy as deliver two small batteries. A tiny step to one day replace the nuclear fission.

13 February 2014 01:06 clock

On the Sun, the fusion of nature works out. Atomic nuclei fuse there at extremely high temperatures. | © Nasa / dpa

In essence, this approach has a major problem. It consumes more power than is gained. For a new form of energy, which will replace about working with nuclear fission nuclear power plants, which is fatal. Since the 1950s, researchers fiddle mind to blend nuclei in reactors. Theoretically, the – albeit just for tiny moments

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Now scientists from the United States have apparently rudimentary the problem with high energy consumption to get a grip: In two cases, the team led by physicist Omar Hurricane by Lawrence Livermore National Laboratory in California succeeded in nuclear fusion, in which less energy in the fuel had to be put into it when it was revealed at the end. About the experiment, the researchers report in the journal Nature .

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from the research also show, however, that the recovered energy was still very low and extremely high energy losses previously existed.

Nuclear fusion is the reverse process, nuclear fission, as it is used in nuclear power plants. According to many physicists controlled nuclear fusion would be the ideal type of energy, because there are enough resources for it to fall over the long term radioactive waste, and the power plants would be relatively safe according to current estimates.

Researchers estimate by the German Max Planck Institute for Plasma Physics in Garching, a gram of fuel in such a fusion power plant could generate 90,000 kilowatt hours of energy. This corresponds roughly to the average electricity consumption of 30 households.

Fusion

Nuclear fusion is a reaction that occurs naturally in the sun. With temperatures around 15 million degrees Celsius in the interior fuse the sun about 100 million bar pressure hydrogen atoms with each other – with the release of helium

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In the 1950s, physicists had for the first time the idea that nuclear fusion artificially induce and so to gain energy. Unlike the nuclear fission – the basic principle of nuclear power plants – would be nuclear fusion less dangerous and would produce less radioactive waste. So far, however, this is the future.

How to operate the nuclear fusion? Click here for an infographic

Existing problems

Since hydrogen nuclei to strong repulsive forces one another exercise that one could merge under terrestrial conditions, researchers use in their research reactors, the hydrogen isotopes deuterium and tritium . These isotopes have to be heated in a reactor to at least 100 million degrees and reaching an extreme density – because only in this state (plasma) can begin a fusion reaction

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the energy would chain reaction of mergers take place. So far, the record of a stable plasma, however, was a few seconds.

Several times researchers have been able to trigger a short chain reaction of mergers in a reactor. So far, however, becoming more more energy than produced . That was in the experiments of U.S. researchers in February 2014 for the first time different.

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Worldwide physicist at the development of nuclear fusion for energy production. The problem: In this case, extremely high temperatures of at least one hundred million degrees necessary and an extremely high pressure from the outside. Such conditions exist, for example, in the interior of stars, when two hydrogen atoms fuse there to form a helium atom. Constantly on the sun fuse atomic nuclei.

On Earth, the scientists have decided to merge two hydrogen isotopes. deuterium and tritium, the reaction also produces helium

Hurricane Omar and his team made it last fall finally to bring about a nuclear fusion by the heat of 192 lasers, in which more energy than before the fuel was supplied. To build a reactor on this basis, the success is therefore not sufficient. To be honest, would have to reckon on also the complete expenditure of energy on the way to fusion with.

And so came at the end for only so much out, as in two AA batteries (not more than 17,000 joules) inserted, and the whole process took less than a billionth of a second over. “We have to reach a hundred times better performance, before we get to the ignition point,” Hurricane said, referring to the point at which a nuclear reaction to permanently carries himself.

The result WOULD far “modest” and that it may be. “But we are the closer to than anyone else before.”