for those on the other end of the heat spectrum... sleeping while sheltering in place without air conditioning in 90F 90% humidity, and no genset to provide power is also a challenge...I've posted this pic before, but for the new members...for the 2004 9 day power outage I used the tent fan pictured (originally with a foam rubber propeller) to help sleep... it was far from satisfactory, but better than none... I later added a collet blade adapter from a model airplane and propeller, to convert it into a motor to spin my ceiling fan... runs 9 hrs on a new "D" cell and 6+ on a pair of Eneloops in a pack...