2021 BRN Discussion, page-15782

Just to add;

if there is a fan, there is a motor driving it.
The motor needs power
power is supplied by a power supply which is never 100% efficient
So there is additional power consumed by the fan motor, and power supply
As well as additional heat generated by the fan motor and fan power supply

Then you need to add the additional mass that the Fan, Fan power supply and the additional battery capacity needed to drive these.
And don’t forget the additional space for the air flow needed. As well as ducts etc..

I have not covered everything above, but it gives you an idea about how much extra staff you need when you introduce cooling, and that is assuming that air cooling will be satisfactory.

Then you need to start thinking about reliability;
each fan has 2 bearings, each motor has 2 bearings and motor driver. For reliability you will need to at least double or quadruple this.
Then you need to add the circuits to control this and monitor the cooling system, as well as a controller to control the fan speed etc etc…

The problem is not trivial

The penalty in power alone can easily add up to more then 100%