I wonder if you could put a small RTG to produce electricity to use for thermoelectric cooling. The RTG would have to run pretty hot but it would be also rather

I wonder if you could put a small RTG to produce electricity to use for thermoelectric cooling. The RTG would have to run pretty hot but it would be also rather simple to create. You need to be able to use temperature differential to produce rotation -- that could be taken care of by simple Stirling engine. Fortunately, given how thick the atmosphere is, the engine would be very small. Another problem is bearings which would be essential to get and keep it running constantly. But here the thick atmosphere also helps. The thick atmosphere would make it easy to create efficient aerodynamic bearing. The last problem is magnets. To produce electricity you need a magnet. Now, looking at a chart I see that there is a bunch of materials with curie temperature higher than temperature on the surface of Venus. Now... just because we can get electronics to run somewhere deep below multiple layers of insulation doesn't yet mean we can do anything useful. For that you need sensors and I don't know what kind of sensors you can build that can withstand that kind of temperature.