Power History refers to the power of a
nuclear reactor
A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat from nu ...
over an extended period of time. Power history is important for calculations and operations that involve
decay heat
Decay heat is the heat released as a result of radioactive decay. This heat is produced as an effect of radiation on materials: the energy of the alpha, beta or gamma radiation is converted into the thermal movement of atoms.
Decay heat occurs na ...
and
fission product poisons and to avoid the
iodine pit
The iodine pit, also called the iodine hole or xenon pit, is a temporary disabling of a nuclear reactor due to buildup of short- lived nuclear poisons in the reactor core. The main isotope responsible is 135Xe, mainly produced by natural decay of ...
during reactor shutdowns.
For example, a nuclear reactor that has operated at 100% power for 100 hours and then has dropped down to 20% power for 5 hours will have a different amount of decay heat and fission product poisons than the same nuclear reactor operating at 20% power for 105 hours. This is because the second reactor has a different power history.
Nuclear technology
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