Current population size in all the settlements on the island and their available housing capacity. Exceeding the capacity leads to an overcrowded island which comes with a monthly Unity penalty.
By dragging the orange slider to the right, you define the desired power level maintained in the reactor. This affects the amount of steam the reactor generates and how fast it burns through the fuel. All the heat generated needs to be used. Any extra heat can slowly build up, eventually leading to a reactor overheating. Basic reactors don’t have automated power regulation which makes their heat output fixed.
Nuclear reactor was critically overheated and is shutting down. Depending on severity, this may cause loss of loaded fuel, damage to the building (loss of maintenance), and leak of radiation.
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