About 1 hour after shutdown, the decay heat will be about 1.5 % of the previous core power.
12.
Beyond that period, heat losses to the air and ground match decay heat generation, without replenishing the cooling water supply.
13.
Decay heat, while dangerous and strong enough to melt the core, is not nearly as intense as an active fission reaction.
14.
The heat of combustion, in combination with decay heat, would probably drive " borderline aged " fuel into a molten condition.
15.
It has ample capacity to replace the cooling water boiled off by residual decay heat, and can even keep up with small leaks.
16.
The decay heat reduces by about 0.8 % per year, so the thermoelectric converter'ages'or degrades to some extent.
17.
Because of the high level of radioactivity, the waste was heating itself through decay heat ( though a chain reaction was not possible ).
18.
This " decay heat " will continue for 1 to 3 years after shut down, whereupon the reactor finally reaches " full cold shutdown ".
19.
After a day, the decay heat falls to 0.4 %, and after a week it will be only 0.2 %.
20.
Any attempts to explain the paradox must therefore factor in both radiogenic contributions, both from decay heat and from any potential natural nuclear fission reactors.
