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Nuclear power fusion

A fast breeder reactor offers one approach to getting more power out of existing uranium sources and potentially reducing radioactive weiste. This type of reactor is so named because it creates ( breeds ) more fissionable material than it consiunes. The reactor operates without a moderator, which means the neutrons used are not slowed down. In order to capture the fast neutrons, the fuel must be highly enriched with both uranium-235 and plutonium-239. Water cannot be used as a primary coolant because it would moderate the neutrons, and so a hquid metal, usually sodimn, is used. The core is surrounded by a blanket of iucmium-238 that captmes neutrons that escape the core, producing plutonium-239 in the process. The plutonium can later be separated by reprocessing and used as fuel in a future cycle. [Pg.937]

Because fast neutrons are more effective at decaying many radioactive nuchdes, the material separated from the uranium and plutonium during reprocessing is less radioactive than waste from other reactors. However, generation of relatively high levels of plutonium coupled with the need for reprocessing is problematic in terms of nuclear nonproliferation. Thus, political factors coupled with increased safety concerns and higher operational costs make fast breeder reactors quite rare. [Pg.937]

In spite of all these difficulties, nuclear power is making a modest comeback as an energy source. Concerns about climate change caused by escalating atmospheric CO2 levels oQo (Section 18.2) have increased support for nuclear power as a major energy source in the future. Increasing demand for power in rapidly developing countries, particularly China, has sparked a rise in construction of new nuclear power plants in those parts of the world. [Pg.937]

Energy is produced when light nuclei fuse into heavier ones. Reactions of this type are responsible for the energy produced by the Sun. Spectroscopic studies indicate that the mass composition of the Sun is 73% H, 26% He, and only 1% all other elements. The following reactions are among the numerous fusion processes believed to occur in the Sun  [Pg.937]

Fusion is appealing as an energy source because of the availability of light isotopes on Earth and because fusion products are generally not radioactive. Despite this fact, fusion is not presently used to generate energy. The problem is that, in order for two nuclei to fuse, extremely high temperatures and pressures are needed to overcome the electrostatic repulsion between nuclei in order to fuse them. Fusion reactions are therefore also known as thermonuclear reactions. The lowest temperature required for any fusion is about 40,000,000 K, the temperature needed to fuse deuterium and tritium  [Pg.937]

Such high temperatures have been achieved by using an atomic bomb to initiate fusion. This is the operating principle behind a thermonuclear, or hydrogen, bomb. This approach is obviously unacceptable, however, for a power generation plant.  [Pg.902]

Numerous problems must be overcome before fusion becomes a practical energy source. In addition to the high temperatures necessary to initiate the reaction, there is the problem of confining the reaction. No known structural material is able to withstand the enormous temperatures necessary for fusion. Research has centered on the use of an apparatus called a tokamak, which uses strong magnetic fields to contain and to heat the reaction. Temperatures of over 100,000,000 K have been achieved in a tokamak. Unfortunately, scientists have not yet been able to generate more power than is consumed over a sustained period of time. [Pg.902]

We are continuously bombarded by radiation from both natural and artificial sources. We are exposed to infrared, ultraviolet, and visible radiation from the Sun radio waves from radio and television stations microwaves from microwave ovens X-rays from medical procedures and radioactivity from natural materials ( TABLE 21.8). Understanding the different energies of these various kinds of radiation is necessary in order to understand their different effects on matter. [Pg.902]


NUCLEAR POWER FUSION We learn that in nuclear fusion two light nuclei are fused together to form a more stable, heavier nucleus. [Pg.909]

After the war, Bethe became deeply involved in the peaceful applications of nuclear power, in investigating the feasibility of developing fusion bombs and bal-... [Pg.144]

Resource pessimists counter that this process cannot proceed forever because the eternal persistence of demand for any given commodity that is destroyed by use must inevitably lead to its depletion. I lowever, the eternal persistence assumption is not necessarily correct. The life of a solar system apparently is long but finite. Energy sources such as nuclear fusion and solar energy in time could replace more limited resources such as oil and natural gas. Already, oil, gas, nuclear power, and coal from better sources have displaced traditional sources of coal in, for example, Britain, Germany, Japan, and France. [Pg.460]

The fear of accidents like Chernobyl, and the high cost of nuclear waste disposal, halted nuclear power plant construction in the United States m the 1980s, and in most ol the rest ol the world by the 1990s. Because nuclear fusion does not present the waste disposal problem of fission reactors, there is hope that fusion will be the primary energy source late in the twenty-first centuiy as the supplies of natural gas and petroleum dwindle. [Pg.481]

The phrase "nuclear power" covers a number of technologies for producing electric power other than by burning a fossil fuel. Nuclear fission in pressurized water-moderated reactors—light water reactors— represents the enrrent teehnology for nuclear power. Down the line are fast breeder reactors. On the distant horizon is nnclear fusion. [Pg.105]

What are the opportunities for using forms of energy that do not lead to CO2 formation Nuclear power from fission reactors presents problems with the handling and deposition of nuclear waste. Fusion reactors are more appealing, but may need several decades of further development. However, solar and wind energy offer realistic alternatives. [Pg.339]

Since about 1940, mankind has realised that energy could be released if the very light nuclei of hydrogen could be made to react to produce deuterium or helium, where nuclear fusion would provide energy. The alternative is nuclear fission of the very heavy elements to give two nuclei of lower atomic number. Already there exist many nuclear power stations using fission but none using fusion. We return to the discussion of the potential value of nuclear power in Chapters 10 and 11. [Pg.41]

The production of 10 TW of nuclear power with the available nuclear fission technology will require the construction of a new 1 GWe nuclear fission plant every day for the next 50 years. If this level of deployment would be reached, the known terrestrial uranium resources will be depleted in 10 years [3], Breeder reactor technology should be developed and used. Fusion nuclear power could give an inexhaustible energy source, but currently no exploitable fusion technology is available and the related technological issues are extremely hard to solve. [Pg.352]

One can consider other energy options. For example, to supply 40 to 60 Terawatts of energy via nuclear fission is possible, it could be done. However it necessitates increasing by almost a factor of x500 the number of nuclear power plants ever built. The consequence of such demand is that we would soon deplete earth s uranium supplies. Breeder reactors are an un-stable possibility, like mixing matches, children, and gasoline. Depending upon ones viewpoint fusion remains either a to be hoped for miracle, or an expensive civil-works project. [Pg.555]

Radioactivity -of fusion reactions [FUSION ENERGY] (Vol 12) -monitoring in nuclear reactors [NUCLEARREACTORS - SAFETY IN NUCLEAR POWER FACILITIES] (Vol 17) -ofnuclear reactor waste [NUCLEARREACTORS - WASTE MANAGEMENT] (Vol 17) -ofpotassium-40 [POTASSIUMCOMPOUNDS] (Vol 19) -role m ore sorting [MINERALS RECOVERY AND PROCESSING] (Vol 16)... [Pg.839]

Fusion reactions can take place only if the reacting nuclei possess sufficiently high energies to overcome their mutual Coulomb repulsion and to approach within the range of nuclear forces, hence they are favored by high temperatures. See also Nuclear Power Technology. [Pg.700]

THERMONUCLEAR FUSION REACTORS. See Lithium Nuclear Power Technology. [Pg.1609]

The fact that neutrons can be absorbed by nuclei without overcoming a threshold (1 = 0 or s-wave reactions) makes neutrons extremely effective nuclear reactants. Neutron-induced reactions are the energy source for present-day commercial nuclear power (fission reactors) while charged-particle-induced reactions remain under study as power sources (fusion reactors). In this chapter we will consider the general features of nuclear fission reactors, following by the general features... [Pg.383]

Fission, on the other hand, is the splitting of a nucleus into parts. This also gives off a lot of energy. Most nuclear power plants in use today use fission reactions, which are easier to contain within the power plant—and therefore are safer—than fusion reactions. Nuclear fission occurs when isotopes of certain elements are hit with neutrons. The following reaction shows what happens to uranium-235 when a neutron hits it. [Pg.21]

In a conventional power plant the molecular energy of fuel is released by combustion process. The function of the work-producing device is to conv part of the heat of combustion into mechanical energy. In a nuclear power pis the fission or fusion process releases the energy of the nucleus of the atom heat, and then this heat is partially converted into work. Thus, the thermodyna analysis of heat engines, as presented in this chapter, applies equally well conventional (fossil-fuel) and nuclear power plants. [Pg.135]

In 1989, the scientific community was startled by the announcement of two chemists that they had succeeded in causing a fusion reaction to occur near room temperature. This coldfusion would have enabled the population of the Earth to be supplied with almost limitless energy without the radioactivity associated with the operation of ordinary nuclear power plants. The effect on the scientific and economic communities was profound. Unfortunately, so far, the results reported by the scientists have not been repeated or confirmed, and cold fusion is still a dream. [Pg.583]

Active searches for alternative forms of energy have been prompted by the growing recognition that reserves of coal and oil are finite and that nuclear power cannot supply all our energy requirements. Hydrogen has been considered as a source of fusion energy and/or clean energy. [Pg.1622]

As we search for the energy sources of the future, we need to consider economic, climatic, and supply factors. There are several potential energy sources the sun (solar), nuclear processes (fission and fusion), biomass (plants), and synthetic fuels. Direct use of the sun s radiant energy to heat our homes and run our factories and transportation systems seems a sensible longterm goal. But what do we do now Conservation of fossil fuels is one obvious step, but substitutes for fossil fuels must be found eventually. We will discuss some alternative sources of energy here. Nuclear power will be considered in Chapter 21. [Pg.383]


See other pages where Nuclear power fusion is mentioned: [Pg.875]    [Pg.902]    [Pg.937]    [Pg.937]    [Pg.875]    [Pg.902]    [Pg.937]    [Pg.937]    [Pg.155]    [Pg.747]    [Pg.815]    [Pg.857]    [Pg.170]    [Pg.21]    [Pg.60]    [Pg.302]    [Pg.15]    [Pg.166]    [Pg.697]    [Pg.46]    [Pg.260]    [Pg.32]    [Pg.513]    [Pg.646]    [Pg.155]    [Pg.280]    [Pg.289]    [Pg.298]    [Pg.67]   


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