This section consists of a few points about the role of the above for temperature regulation in space colonies or spaceships.
Any habitat needs light.
This may be provided as sunlight or artificial light, but whichever, it will introduce energy, much of which will end up as heat, thus tending to increase the temperature of the habitat. In spaceships, the engines would be yet another heat source. Nothing too remarkable about that, just simple physics. The temperature of the entire habitat would increase until it reached an equilibrium value at which it was losing as much energy by radiation to space as was being put in from whatever source. From the point of view of this section, the thing to be careful of in habitat design is that said equilibrium value should not be so high as to prevent the habitat's functioning.