Look up the Wonderwash. It basically looks like a small propane tank on an axle that you manually spin to wash your cloths. It works surprisingly well for washing cloths without electricity.
How long does it take to manually dry a normal load with that thing? My dryer takes at least an hour to dry a modest sized load of normal clothes so I would expect a non-powered one to take many hours, but maybe my modern dryer is really so bad it doesn't save much time.
With the first few loads I wrung cloths out by hand and tossed them in the dryer. I didn't notice it being longer, but I also didn't time it so 20-30% longer wouldn't surprise me.
After a few loads I bought a hand crank cloths wringer, basically two rollers that squeezes the water out. That thing honestly works better than a spin cycle, cloths are more dry than coming out of the washer and I have noticed the dryer finishing faster (I usually run it on an auto sense mode rather than a timer).
