Power history
Encyclopedia
Power History refers to the power of a nuclear reactor
over an extended period of time. Power history is important for calculations and operations that involve decay heat
and fission product poisons and to avoid the iodine pit
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 reactor
A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid , which runs through turbines that power either ship's...
over an extended period of time. Power history is important for calculations and operations that involve decay heat
Decay heat
Decay heat is the heat released as a result of radioactive decay. This is when the radiation interacts with materials: the energy of the alpha, beta or gamma radiation is converted into the thermal movement of atoms.-Natural occurrence:...
and fission product poisons and to avoid the iodine pit
Iodine pit
Iodine pit, also called iodine hole and xenon pit, is a temporary disabling of a nuclear reactor due to buildup of short-lived nuclear poisons in the core of a nuclear reactor. The main isotope responsible is xenon-135, mainly produced by natural decay of iodine-135. Iodine-135 is a weak neutron...
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.