"The older designs are simpler and not so power-intensive, therefore having less heat to be irradiated and so do not need to maximise surface area with a saucer."
I would've thought that they had heat to electricity direct conversion technology by then.
The second law of thermodynamics requires that entropy must increase; while some fraction of heat may be recycled, any gained energy eventually must degrade into heat.
For a vessel to remain in thermal equilibrium (have a comfortably constant temperature onboard), the power coming in must equal the power coming out. The temperature of the vessel, in vacuum, will rise if it can not radiate the equivalent of the power it absorbs. Measures can be taken to reduce how quickly temperature rises, but it is inevitable.
"The older designs are simpler and not so power-intensive, therefore having less heat to be irradiated and so do not need to maximise surface area with a saucer."
I would've thought that they had heat to electricity direct conversion technology by then.
The second law of thermodynamics requires that entropy must increase; while some fraction of heat may be recycled, any gained energy eventually must degrade into heat.
For a vessel to remain in thermal equilibrium (have a comfortably constant temperature onboard), the power coming in must equal the power coming out. The temperature of the vessel, in vacuum, will rise if it can not radiate the equivalent of the power it absorbs. Measures can be taken to reduce how quickly temperature rises, but it is inevitable.