I have a return in my basement. I also have return on the first and second floor of my house.

On a mild warm day I may run the fan to circulate from the basement to the second floor. The cooling effect is limited. The temperature in the basement will be around 68 degrees. I may be able to get the temperature down one degree (79 to 78). Most of the relief come from the wind chill effect of the cooler air blowing on your skin.

The set up does not work when the temperature is in the 90s and the sun is beating down on the house. You also run the risk of bringing more moisture into the house form the basement. This will make it more uncomfortable.

I just open the door to the stairwell going down into the basement. I rarely need air conditioning. Opening a window or two can help. The upward draft of the hot air trying to leave the house draws the cooler air up from the basement. So, no fans needed. My house is also 1 story not counting the basement and is only 1000sq.ft. Avg summer time temps in my house were 80-85F, which is fine with me.

Thanks for replies. It's always a good 10 degrees cooler in the basement that upstairs. I'm going to research it more - gotta be a way to channel that air up one flight of stairs!

My concern would be possible radon infiltration if in doing your air circulation you create a negative pressure in the basement area. I don't think it is worth it for the limited amount of cool clammy air you have in the basement.

I often run the furnace fan to bring the cool basement air up through the registers. I do have central air but only use it when heat is really oppressive. I love open windows whenever possible.

In basement air circulation is always the problem, what i do is just use fan and open windows, and not to forget controlling the humidity cause it might cause mold growth so we have a dehumidifier to maintain the humidity level