Nuclear energy is on the one hand the form of primary energy, which is set free with nuclear reactions, in particular with the nuclear fission and nuclear fusion. On the other hand thereby the technology and industry become the industrial production of secondary energy, as designates electric current, from nuclear energy. While nuclear fusion reactors are only in the research stage, the nuclear fission is used already for the 1950er years in nuclear power stations - predominantly using the source of energy uranium - generally speaking yardstick.

Term history

Originally the physicist Hans Geitel 1899 coined/shaped the term atomic energy for the phenomena arising in connection with radioactive decay processes; later the often synonymously used terms nuclear energy, nuclear power, nuclear power and nuclear energy were added.

The use of these terms has a contentwise since Geitels of first term coinage both, and a social differentiation experience. At the same time with the increasing use of the terms atomic energy and nuclear power by nuclear power opponents these found less and less to use in economics, politics and science. Instead nuclear energy in the atomiclegal, nuclear energy and nuclear power in the scientific and economic surrounding field are used. In addition the term nuclear power is used in nuclear physics also as name for the strong reciprocal effect.

Physical background

Most frequently used nuclear reactions for the utilization of nuclear energy are the induced nuclear fission and the nuclear fusion.

During the induced nuclear fission the atomic nuclei of heavy uranium, thorium, or disintegrate plutonium isotopes into several lighter cores, as soon as them a small activation energy - receive by penetration of a neutron into the core. The difference between the mass of the origin core and the sum of the masses of the fission products, also as mass defect admits, thereby to the equivalence of mass and energy into kinetic energy is converted. Per splitting this is about 200 MeV. Among the fission products rank also 2-3 prompt neutrons, which are set free with each splitting. These can induce and lead further nuclear fissions so to a nuclear chain reaction. The retarded neutrons resulting from radioactive decay of the fission products make a steered nuclear chain reaction possible in a nuclear reactor.

With the nuclear fusion several light atomic nuclei, like the hydrogen isotopes deuterium and tritium, are merged into a heavier core, about a helium isotope. Since atomic nuclei are positively charged, for it the Coulomb force, which causes a repulsion of the cores, must be overcome. In addition a high pressure and a very high temperature about 100 million Kelvin are necessary -. As is the case for the nuclear fission by the mass defect a part of the core binding energy, depending upon reaction in the order of magnitude of approximately 3-18 MeV per fusion, is set free.

History

Around 1890 first experiments were accomplished to the radioactivity. The goal Antoine Henri Becquerels, Marie and Pierre Curies and other one was the research of nuclear reactions. 1938 discovered Otto cock and Fritz Strassmann the induced nuclear fission of uranium, which 1939 were theoretically explained by Lise Meitner and Otto freshness. Together with in particular the proof furnished by and Joliot curies that a nuclear chain reaction is possible, became the practical application possibilities of the nuclear fission clearly.

First these realizations were used for the military research during the Second World War. In the context of the Manhattan project Enrico Fermi succeeded on 2 December 1942 the first controlled nuclear nuclear chain reaction in a nuclear reactor in Chicago (Chicago Pile One). While the goal of the Manhattan project with the first successfully ignited atom bomb, led by Robert Oppenheimer, was achieved on 16 July 1945 (Trinity test), it did not succeed to the German research group under Werner Heisenberg and Carl Friedrich from to the end of war to develop a functioning nuclear reactor (uranium project).

Also after the Second World War the military research was continued. Thus on 31 October 1952 the first hydrogen bomb was ignited, with which the nuclear fusion application finds. In addition, at the same time at the civilian use of the nuclear energy one researched. 1954 were taken in Obninsk with Moscow the first nuclear power station in enterprise. 1955 followed the first commercially nuclear power station in Calder, used for generation of current, resound (northwest England). In Germany 1957 with the Atomei were taken in Garching the first research reactor in enterprise. 1961 followed the first German nuclear power station in bald at the Main with an output of 15 MW.

Into the 1960er years numerous further nuclear power stations were built, whereby their achievement was increased clearly. So the nuclear power station Gundremmingen, which 1966 went into enterprise, had an output of 250 MW. 1968 were taken the ore carrier "Otto cock" as nuclear operated research cargo ship in enterprise; after the end of the nuclear enterprise 1979 the freighter was reequipped Diesel drive. Into the 1970er years after the first oil crisis 1973 the building was forced in particular by nuclear power stations. The achievement of these power stations, as for instance the block B of the nuclear power station Biblis, was with 1,3 GW. With the protest of the nuclear power opponents against the building of a nuclear power station in Wyhl at the emperor chair 1975 a larger opposition developed against the civilian use of the nuclear energy in Germany. This strengthened itself still in particular by the heavy reactor misfortune in the nuclear power station Three Mile Island with Harrisburg (the USA) to 28. March 1979, at which it came to a partial core melt-through.

1983 were taken in Hamm Uentrop the thorium high-temperature reactor THTR-300 in enterprise. This prototype was shut down after several technical disturbances six years later. Due to the political arguments around the nuclear energy no agreement could be obtained over the necessary extent of necessary repairs, why the THTR was taken among other things for economic reasons not again in enterprise, but transferred into the safe inclusion.

On 26 April 1986 the disaster of Tschernobyl occurred, with which large quantities of radioactivity were set free. In the consequence in particular the criticism increased in the use of the nuclear energy clearly in Europe. 2000 were decided in Germany on pressure of the Federal Government the door from the commercial use of the nuclear energy to approximately 2020. In this framework until already 2005 two nuclear power stations were taken by the net, the door resolution are however politically and socially further disputed. Similar the situation is for example in Italy, Belgium or Sweden. In other countries against it, in particular in the USA, the running times of existing nuclear power stations are extended or built at present (conditions 2006) new nuclear power stations (for example in India, Russia, China and Japan). In the USA an extensive development program for new nuclear power stations (the so-called "fourth generation ") was presented. In Olkiluoto (Finland) on 12 August 2005 with the building of the first power station of the type European Pressurized Water Reactor (EPR) was begun with an output of 1,6 GW; France seized the building decision for an identically constructed nuclear power station in Flamanville. (see also: Nuclear energy to countries)

Economics

The most important application of the nuclear energy is the production of electric current in nuclear power stations (KKW). Zurzeit are 442 nuclear power stations with a total output of 369 GW in 30 countries in enterprise. 135 of these nuclear power stations stands in Western Europe (124 GW), under it 17 in Germany (20 GW) and 5 in Switzerland (3.2 GW). Austria does not have nuclear power stations in enterprise. In 9 countries, under it Finland as only Western European country, are altogether 24 nuclear power stations with a total output of 20 GW in building. (Conditions October 2005)

The portion of the atomic energy of the world-wide energy production amounted to 1998 6.5% (UNDP). The atomic current portion of the world-wide generation of current amounts to about 16 %. Lithuania and France with nearly 80 take % portion the point places. In Western Europe about 30 % of the electric current by nuclear energy one produces, in Germany 28 % and in Switzerland for scarcely 40 %.

In Belgium, Germany and Sweden a door from the commercial use of the nuclear energy is planned.

A further application - the nuclear energy drive - became generally accepted outside from militarily used nuclear-powered submarines and ships only (partly) with ice-breakers.

Articles in category "Nuclear energy"

We found here 246 articles.