"I have doubt about this claim of using less energy, but have not performed the calculations. Have you?"
Yes.
Calculation Eyewitness hygrometer and thermometer readings versus a utility kWh meter.
And the difference wasn't subtle.
Warmer air holds more moisture. Much more moisture.
Desert climes can support wildlife with morning dew yet desiccate like a fruit dryer in the afternoon.
The thing I noticed most is that it takes a much larger machine than "theory" pencils out. My tiny abode squeezes out 8 gallons a day but this is in the tropics. 20 pints for an RV would not be irrational but remember it is -much- harder to squeeze moisture out of 80F air than it is for 90F air.
When I lived on the northern California coast 40 years ago, I used a dehumidifier to -heat- the bedroom. Fifty degrees with 80 percent humidity is a Mark Twain San Francisco Summer.
In Quicksilver I have one of the girls hoist a dehumidifier and set it atop the kitchen sink.
But thinking a heater and an A/C makes a good dehumidifier is a serious error.
