I’m reconfiguring my printing closet (~6’x6’) for a new printer and thought about enclosing the printer in a moderate sized cabinet (~2’x3’x6’ - one “shelf” of the closet) for thermal control. Since there will be inevitable opening and closing, as well as just normal infiltration of the ambient air (usu ~65F between 40-75% RH) it would seem like a good application for a Peltier dehumidifier to keep the RH in the chamber low and reduce my need to re-dry filament which has been on the machine during (inevitable) multi-day or -week downtime between projects.
You’re thinking of carnot efficiency power cycles where you are removing energy from a fluid, maybe? I meant exactly what I said with their COP.
Refrigeration/heat pump cycle COP’s can be all over the place. Often they are much higher than 1.0. Where a refrigeration cycle’s COP is calculated as Q(cold) / Work(electrical), many heat pumps can move more watts than they take to run. TEC’s are no exception.
TEC’s in particular are especially sensitive to the total temperature differential between hot and cold plates when it comes to COP. They hate making temperature differentials much higher than 30-40 kelvin. Most efficient when the temperature delta is like 10K or less. COP 0.6 is about typical for a TEC running across the fairly large temperature differential that you would need to get air down to dew point and condense water, at a high current required to make the TEC’s cost effective. Example graph of COP vs temperature differential