As a demonstration of the entropic forces of a rubber band, an engineer by the name of Ben Krasnow just created a refrigerator that uses rubber bands to keep itself cool.
If you didn’t understand anything about what we just said, it’s not a problem, since the only purpose of the build itself is to make you understand.
This special concept contraption, called the Rubber Band Refrigerator, takes it’s inspirations from other designs that don’t use electricity as a crutch, rather relying upon physics to help them out.
We of course are referring to the Mittocool Fridge, which used the physical properties of mud as a means to keep the contents inside cool.
Following a similar, yet different approach, this special fridge takes advantage of a rubber bands ability to heat up when stretched, as well as cool down when allowed to contract.
Putting this ability to use, they designed a small construct made out of wood. The design comes with a built in offset wheel of rubber bands.
This wheel is operated through hand cranking, which causes the rubber bands to stretch outside the fridge, and release inside it. Through this motion, the contracted rubber band gets exposed to the air of two fans.
This air helps transfer the thermal energy from the bands to the air inside the box, where the items to be cooled off are kept. As a result of the entire exercise, the temperature inside the refrigerator goes down.
While you can clearly see that this design isn’t exactly practical for regular use, it still is a great demonstration of how we can use physics to do our bidding.