I bought an arctic air cold water evaporator. It work well for near field personal cooling.
So even though its summer time. I wonder. Could you heat a room or create near field warming. This with hot water instead of cold.
Perhaps the water temperature only need to be 35 degrees celsius and not boiling. Since this would break the device. Then the evaporation cools it down a bit. But it should still be warm. A 10 degree drop I guess.
Could be the most efficient way to save money on electricity. USB powered heater. But I think there needs to be a special version of the device.