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Ok - purely on the fun side - I've been playing around with the idea of a fully electric dephlegmator/reflux-condenser using TEC/Peltier Modules and air-cooling.
I've used Peltier modules in other hobby projects a few times, and they are generally easy to use, easy to control, fairly responsive (depending on the thermal mass). They have also gotten to be incredibly inexpensive. Even what was historically a very large element, and hugely expensive, can be had for a couple bucks - though larger 250w+ modules will still run around $25usd a piece.
Using multiple lower wattage elements - you could get close to 1kw of cooling capacity for less than $50usd - elements only - power supply and controls is another factor.
Some have gone this route, but still used water as the cooling medium. My thought is to eliminate the intermediary, as water poses additional complexities, and an all-electric system would be a much more simplified approach.
Control would be relatively simple, and actually very similar to controlling the heating elements - you would simply manage total power input to the TEC/Peltier elements to control knockdown. You could monitor vapor temp, but from a stability and repeatable perspective, managing wattage input would be very easy.
Why I think this has merit? Theoretically - very fast, and very accurate temperature control, based on the thermal mass, could be very quick to respond. I am wondering if this would provide a mechanism to PID control with Vapor Temperature as the PV (not dephelgmator water temperature).
The real challenge here is the metalwork required, as TEC modules need good parallel surfaces for heat transfer, large heatsinks (with fans) - AND - the cold side would need to have a similar cold-sink, which protrudes through the column into the vapor stream. If you have a machine shop, or know someone who does - shouldn't be terribly complex - but trying to do this in a garage workshop - going to be tough.
I've got a few sketches and some ideas for mounting multiple modules around the TEC "dephlegmator". The most realistic design uses multiple modules mounted in square around a central circular column - as there would be no realistic way to make a top-mount unit - simply not enough real estate to add enough TEC modules.