I have a shop fan on my porch that I leave on 24/7 when it’s humid out. It has three speeds. The lowest speed is rather noisy.

If I don’t run it, humidity condenses on the front door. Then mosquitoes are attracted to the moist door. And this leads to them sometimes entering the house.

I bought this ($19), so I can dial the lowest speed even lower to the exact point the noise is low enough but the wind is fast enough.

It was just a thought that occurred to me since it’s electric, could it not be run at a different speed if the input electricity was changed?

Yes, it can. Works beautifully.