In a nuclear fission reaction as installed in Indian nuclear power plants, the energy released in this nuclear reaction is seen to be greater than the mass defect and as such in a nuclear power plant, the fuel consumption is few kg per annum and generation of energy is quite sustainable. It is thought the energy release has some other relationship rather than mass defect as we generally think. A nuclear scientist can answer this question.
The energy that can be released from any nuclear process originates from gaining binding energy when a more stable state is reached. Thus, this amount of energy can be set free and the remaining product nucleus (or nuclei) are correspondingly lighter then the educt(s). This is the commonly accepted model to describe nuclear decay, fission, fusion, stellar nucleosynthesis, neutron activation etc. Any hint that the released energy E_r does not exactly correspond to the mass defect Delta_m connected via the equation E_r=Delta_m c^2 would contradict so many accepted facts that any such claim would need very strong experimental evidence to be taken seriously.
You are right, Erik Strub, binding energy from higher reactants to lower products is definitely a source of energy available in nuclear reaction in addition to mass defect, E_r = Delta_m c^2. But still then from the mass of fuel consumed in a nuclear power plant and energy generated during the same period, the quantum of energy seems much more as compared to fuel spent.It seems some intermediate products are there and the reaction proceeds in a sustainable manner, as we see in sun's energy an ever ending process. The related theory on this concept may be developed with hands on laboratory experiments.
A big power plant has a thermal power of about 4 GW . So in a year (365x86400 s), the released energy is approximately 1.2e17 Ws (4e9 x 365 x 86400) . Using E=mc^2, this corresponds to a mass loss of Delta_m = 1.2e77 / (3e8)^2, so approximately 1.4kg of matter are transformed into energy.
Such a reactor burns approximately 30.000 kg fuel in a year, at a U-235 content of roughly 5 %. So that's 1500 kg U-235. Now you can calculate that the fission products (e.g. Mo-99, Xe-134 and two neutrons as a possible combination) have together a mass of only 234.83 while U-235 hass a mass of 235.04. This is a mass defect of about 0.1%, or, related to the original 1500kg U-235 in the core, about 1.5kg. Which corresponds very well with the 1.4 kg I estimated above. No new theory needed for that.
If you have other data, what are your sources?
Thank you, Mr.Erik Strub for your detailed calculation of nuclear fuel consumption for a 4GW nuclear power plant for one year. 1.5 kg of pure U-235 required for a period of one year is extracted from 30,000 kg (30 MT)/year of the ore is a vivid calculation. The loss of mass which we refer as mass defect is matching very closely(1.4 kg). Thank you again for your clarification. Please send me your e-mail ID to ([email protected]) for further few personal questions.
Some of neutrons are captured in fertile nuclei, thus producing more fissile material. Have you considered this in your question / reply / calculation? This essentially reduces to a question of the definition of the fuel.
Mr.Vid Merljak, thank you for your alertness. Your alertness will take you to the sky high.All aspects have been dealt with before raising this common phenomenon.
I think careful calculations of the mass energy relation not give excess energy than the mass defect. If there is such result then it has to be verified with experimental results as stated by Eric.
Kindly check here too..
https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/nuclear-chemistry-19/nuclear-reactions-135/nuclear-binding-energy-and-mass-defect-540-3600/
Mr.Surender Singh, please express your personal opinion on the subject from your vast source of acquired knowledge and experience.
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