[Greenbuilding] portable fan efficiency

[Reuben Deumling]

Do portable fans, which those of us who live in climates that rarely get hot
sometimes employ on those rare hot days, come in more and less energy
efficient versions? The one I have is a cheap 20" Lakewood model I found
discarded on the curb. It has three speeds, which draw 75, 95 and 120 W. I
have no idea how many cubic feet per minute this fan moves. It does the job,
but uses plenty of power, in my opinion. Is this as good as it gets for such
a device? It is tempting to rig up a solar panel to a 12 V version of one of
these, but the ones I've encountered online cost many hundreds of dollars.

Thanks for any tips.

Reuben Deumling